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PET/MR Molecular Imaging of Cancer

October 16, 2024

Yale Cancer Center Grand Rounds | September 17, 2024
Presented by: Georges El Fakhri, PhD, DABR

ID
12218

Transcript

  • 00:00My name is Pam Coons.
  • 00:02I'm one of the GI
  • 00:02medical oncologists. It's my pleasure
  • 00:05to introduce doctor George El
  • 00:07Fakhry,
  • 00:08for today's,
  • 00:10YCC Grand Rounds speaker.
  • 00:12He is the I'm gonna
  • 00:13do a brief introduction. I
  • 00:14promised him I wouldn't. He
  • 00:15has so many publications and
  • 00:17awards, but I won't read
  • 00:17all of them. So doctor
  • 00:19Elfackery is the Elizabeth Mears
  • 00:21and House
  • 00:22Jamieson professor of radiology and
  • 00:25biomedical engineering and of biomedical
  • 00:27informatics and data science at
  • 00:28Yale School of Medicine. He
  • 00:30has been here almost exactly
  • 00:32one year. Last year, October
  • 00:33first was his anniversary.
  • 00:35He also serves as a
  • 00:36vice chair for scientific research
  • 00:38in radiology and the director
  • 00:39of the Yale Pet Center.
  • 00:42He has a PhD in
  • 00:43medical physics,
  • 00:44an MS in biomedical engineering
  • 00:46from the Paris Sud University,
  • 00:48and an MS in electrical
  • 00:50and com computer engineering
  • 00:52from the University of Texas
  • 00:54at Austin and a master's
  • 00:55of engineering from a close
  • 00:57central in France, and I
  • 00:59probably mispronounced that. But he
  • 01:01is internationally recognized,
  • 01:03in quantitative
  • 01:05molecular imaging for in vivo
  • 01:06assessment,
  • 01:08of pathophysiology
  • 01:09in brain, cardiac, and oncologic
  • 01:11disease.
  • 01:12His current areas of research
  • 01:14include high resolution PET MR
  • 01:16imaging in a range of
  • 01:17diseases,
  • 01:19including neurodegenerative
  • 01:20disease, traumatic brain injury, cardiac
  • 01:22disease, and oncology. Cology. It's
  • 01:24really
  • 01:26personally, really a pleasure to
  • 01:27partner with him as we
  • 01:27think about pet imaging and
  • 01:27oncology, my area of expertise
  • 01:29in neuroendocrine
  • 01:30tumors and as we think
  • 01:31about really bringing some of
  • 01:32his expertise,
  • 01:33to clinic. So,
  • 01:38thank you so much for
  • 01:39joining us today.
  • 01:42Thank you very much, Pam,
  • 01:43for the kind introduction.
  • 01:45I I was reminded it's
  • 01:46almost a year I've been
  • 01:48using nine months as an
  • 01:49excuse that I'm not
  • 01:51ready yet, but I guess
  • 01:52that's run out now.
  • 01:54So it's a pleasure to
  • 01:55be here and to share
  • 01:56with you,
  • 01:57some of what PET NMR
  • 01:59can do for you.
  • 02:01Part of my job coming
  • 02:02in here was to, go
  • 02:03below the neck because the
  • 02:05Pet Center is world renowned
  • 02:07in neuroscience. And,
  • 02:09we hope that,
  • 02:12I'll give you a taste
  • 02:12of what you can be
  • 02:14doing with Pet, and with
  • 02:15MR,
  • 02:18in a center near near
  • 02:19you. So I'd like to
  • 02:21acknowledge,
  • 02:23our funding that comes mostly
  • 02:24from the NIH. And I
  • 02:25would like to give a
  • 02:26shout out to,
  • 02:28not only the PET center
  • 02:29that you see in this
  • 02:30slide, but also the, the
  • 02:32imaging group, at Yale. That
  • 02:34was from Friday,
  • 02:36where we had our first
  • 02:38mini retreat. And, they're a
  • 02:40pet center. There's an MR
  • 02:42center. There's an image processing
  • 02:43group over two hundred faculty
  • 02:44and postdocs,
  • 02:46that do anything that has
  • 02:47to do with PET, MR,
  • 02:48or optical in all parts
  • 02:49of the brain.
  • 02:51If you are interested in
  • 02:52any of the imaging,
  • 02:54all what I'll be showing
  • 02:54today is available today at
  • 02:56ATL.
  • 02:58Some of it may be
  • 02:59about to start, because nine,
  • 03:01I just keep saying nine,
  • 03:02eleven month is a short
  • 03:04time. But, from for the
  • 03:05most part, it's, all available
  • 03:07now, as a revenue neutral
  • 03:10core. So,
  • 03:11please give me a a
  • 03:12line if you're interested in
  • 03:14any of this.
  • 03:15This is the core I'm
  • 03:16referring to, so
  • 03:17we do everything from mice
  • 03:19to men,
  • 03:20including,
  • 03:22some animals you may not
  • 03:23recognize.
  • 03:25Many, many of you are
  • 03:26users of the core. I'm
  • 03:27not gonna go through all
  • 03:28the animals, but there's a
  • 03:29woodchuck there and a rabbit.
  • 03:32The,
  • 03:33some of you are, actually
  • 03:34users of the core.
  • 03:38There,
  • 03:39you are in many, many
  • 03:40departments, and we do everything
  • 03:42from cell culture to phase
  • 03:44one in the core.
  • 03:46So I'd like to start
  • 03:47with a quick slide about,
  • 03:50maybe that's one of the
  • 03:51very few about modalities,
  • 03:53talking about PET NMR.
  • 03:56To highlight that
  • 03:57these two modalities are quite
  • 03:59symbiotic in that
  • 04:01PET is a very high
  • 04:02sensitivity modality where we image
  • 04:04picomolar concentrations. You'll hear me
  • 04:05often during the talk today
  • 04:07talk about,
  • 04:09you know, measurements that are,
  • 04:11at the cellular level.
  • 04:13Something we cannot do with
  • 04:14MR.
  • 04:15We are nowhere near the
  • 04:17picomolar or the nanomolar really,
  • 04:20in MR.
  • 04:21But in PET, we have
  • 04:22a very poor resolution and
  • 04:24everything is relative. I hope
  • 04:25by the end of the
  • 04:26talk, I would convince you
  • 04:27that's not anymore the case
  • 04:29because you'll see images with
  • 04:30a one millimeter resolution in
  • 04:32PET.
  • 04:33But for all intents and
  • 04:34purposes, our scanners today are
  • 04:36in the four, five millimeter
  • 04:37resolution whereas in MR,
  • 04:39our resolution is exquisite.
  • 04:42We can form many, many
  • 04:44images in a very short
  • 04:45time without any ionization.
  • 04:47Quantitation is quantity is challenging
  • 04:49in MR and that's what
  • 04:50we do on a daily
  • 04:51basis in PET. So you
  • 04:53can see that the strength
  • 04:54of PET and MR are
  • 04:55really the weaknesses of the
  • 04:57other modality. And what I'm
  • 04:58gonna try to show you
  • 04:59today is putting those together,
  • 05:00there are a lot of
  • 05:01things we can do in
  • 05:02cancer
  • 05:04that
  • 05:05get us to the heart
  • 05:06of many diseases.
  • 05:07I tried to I will
  • 05:09try to show this by
  • 05:10body part
  • 05:12in the spirit of a
  • 05:13grand rounds. But you'll see
  • 05:14that a lot of those,
  • 05:15there's symbiosis between the two.
  • 05:18Our efforts, are part of
  • 05:20actually a center of excellence
  • 05:22that is one of, twenty
  • 05:23in the country. This is
  • 05:24the one in Panama. It's
  • 05:25the only one in Panama,
  • 05:28in the nation. And there's
  • 05:29several pieces we are
  • 05:32supposed to be doing in
  • 05:33this center. One of them
  • 05:34is developing new targets, and
  • 05:36I'll show you some of
  • 05:37the radiochemistry for some of
  • 05:38these targets,
  • 05:39the ones that are in
  • 05:40cancer.
  • 05:42But they're also a whole
  • 05:43component in terms of,
  • 05:45image analysis and processing and
  • 05:47in terms of dissemination.
  • 05:49And I mentioned this because
  • 05:51it is part of our
  • 05:52job to,
  • 05:54disseminate our work to as
  • 05:56many users who are interested
  • 05:57as possible,
  • 05:58provided their NIH users per
  • 06:00NIH rules. But, actually, we
  • 06:02often break that rule and
  • 06:03we work with everyone. So
  • 06:04if you are interested in
  • 06:05any of this, please do
  • 06:07let me know and we
  • 06:07can, discuss afterwards.
  • 06:11So I thought I would
  • 06:11start in the head because,
  • 06:12well, it's,
  • 06:14the highest up. And, as
  • 06:15I mentioned, we do a
  • 06:16lot of work's being done
  • 06:17in the brain.
  • 06:19And I would like to,
  • 06:20I don't know if we're
  • 06:21supposed to be monitoring the
  • 06:22chat. Oh, this is for
  • 06:24you guys. If you wanna
  • 06:25have CME attendance, please text
  • 06:26four six seven nine three.
  • 06:29I think from here on
  • 06:30out, we won't look at
  • 06:30the chat until the end.
  • 06:32So,
  • 06:34I'd like to start with
  • 06:35some work in MR spectroscopy
  • 06:37actually.
  • 06:38And this is a nice
  • 06:39success story because there's been
  • 06:40a lot of work going
  • 06:41in my lab in this
  • 06:42area led by Chang Ma.
  • 06:44And there's a lot of
  • 06:44work happening here at Yale
  • 06:46in spectroscopy that I will
  • 06:48feature some of, and you'll
  • 06:49see how the two come
  • 06:50together in terms of imaging.
  • 06:52The basic idea is that
  • 06:55for a long time, what
  • 06:56we have done in spectroscopy
  • 06:57is looking at a voxel.
  • 06:58So if you if you
  • 06:59knew where to look, you'll
  • 07:01get a good answer. And
  • 07:02what you'd hear often is
  • 07:03spectroscopy has good potential, but
  • 07:05it was never something that
  • 07:06is done
  • 07:08routinely in the clinic.
  • 07:09I hope today I'll I'll
  • 07:10convince you that now there's
  • 07:11quite a bit that you
  • 07:12can do in the clinic
  • 07:13without a major burden for
  • 07:15your,
  • 07:16for your workflow.
  • 07:19This is just to show
  • 07:20you that the trick and
  • 07:21what I'll be showing you
  • 07:22in terms of imaging
  • 07:23is not to image the
  • 07:25whole space,
  • 07:26but to only image what
  • 07:28we're interested in in terms
  • 07:29of metabolites,
  • 07:31because that allows us then
  • 07:33in our reconstruction of the
  • 07:34image to go much faster.
  • 07:36And instead of, having, you
  • 07:38know, a one scan or
  • 07:39one voxel,
  • 07:40to have a quantitative t
  • 07:42one, t two, and, myelin
  • 07:44water fraction and everything else
  • 07:45you're interested in,
  • 07:47in a time that is
  • 07:48very reasonable,
  • 07:50for MR, about eight minutes,
  • 07:51but with a resolution that
  • 07:53is very good. We're talking
  • 07:54about, you know, one by
  • 07:55one by two millimeters
  • 07:57or two by two by
  • 07:58three millimeters.
  • 07:59And from that, we can
  • 08:00estimate then the,
  • 08:02all of the,
  • 08:03different metabolites we can add.
  • 08:05We're showing you here choline,
  • 08:07creatidine,
  • 08:08CAI, glutamate,
  • 08:09glutamine.
  • 08:12I will have very few
  • 08:13images in normal subjects only
  • 08:15just to make a case.
  • 08:16I know this is a
  • 08:16cancer round, but this is
  • 08:17one of them.
  • 08:19And now we look at
  • 08:20a brain tumor, and you
  • 08:21can see that,
  • 08:23now the value of having
  • 08:24a whole image of spectroscopy
  • 08:26as opposed to a whole,
  • 08:28voxel spectroscopy,
  • 08:30is that now we can
  • 08:31assess in the entire brain,
  • 08:33the different signatures of the
  • 08:35tumor, the tumor rim, the
  • 08:37necrosis necrotic component, and the
  • 08:39edema, which have different signatures.
  • 08:42We can push this, further
  • 08:45and look
  • 08:46at,
  • 08:47actually, this is a little
  • 08:48longer now. It's, it's twelve
  • 08:50minutes, but, you can see
  • 08:52here that,
  • 08:54the signature on the different,
  • 08:56metabolic components,
  • 08:57for example, the lactate and
  • 08:59the choline are very different
  • 09:00for the same tumor.
  • 09:02And that allows you to
  • 09:03start having some insight into,
  • 09:06you know, what is the
  • 09:07hypoxic component, what is the
  • 09:08two HD or the IDH
  • 09:10mutation,
  • 09:11for that
  • 09:12for that glioma in this
  • 09:13case.
  • 09:15And then this is in
  • 09:16the Maersh spectroscopy side.
  • 09:18We can also add the
  • 09:19PET. Just one more slide
  • 09:21to show you that this
  • 09:22is not just a pretty
  • 09:24image.
  • 09:24What I'm showing you here
  • 09:26is the,
  • 09:27on top is the the
  • 09:28clinical t one weighted and
  • 09:30FLAIR t two.
  • 09:31And in the middle row
  • 09:32is the quantitative t one
  • 09:34t two maps.
  • 09:36And,
  • 09:37in the bottom are the,
  • 09:39NAA choline lactate.
  • 09:41It's not just a pretty
  • 09:42image. You can see that
  • 09:44the discrimination we have and
  • 09:46this is the manual annotation
  • 09:48by the,
  • 09:49neuroradiologist.
  • 09:50You see the discrimination between
  • 09:52the,
  • 09:53edema and the tumor
  • 09:55is done much better
  • 09:56when you have access,
  • 09:59to your, metabolic images from
  • 10:01MRSI
  • 10:02than it is when you
  • 10:03have access only to your
  • 10:05clinical MR. It is not
  • 10:07as different when you're looking
  • 10:08at the lesion versus normal.
  • 10:10There, it's pretty clear.
  • 10:12I want you to look
  • 10:12at the green
  • 10:14curve and the blue curve.
  • 10:15These are the receiving operating
  • 10:17characteristics. So the ROC curves
  • 10:19for,
  • 10:20what is true.
  • 10:21And you can see that
  • 10:22we do a lot better
  • 10:23when we have
  • 10:25the MR,
  • 10:26s information compared to when
  • 10:28we have only the MR
  • 10:29information.
  • 10:31And next, we're gonna look
  • 10:32also at, we can add
  • 10:34the PET.
  • 10:36And we can see that
  • 10:37in this case,
  • 10:38we're looking at an amino
  • 10:40acid, the, fluoroethyl,
  • 10:41tyrosine
  • 10:42in addition to tyrosine in
  • 10:44addition to the MRSI.
  • 10:46And and I hope you
  • 10:47can see where I'm going
  • 10:48with this. The idea is
  • 10:49that now
  • 10:51we can see on the
  • 10:52t two flare, well, the
  • 10:53entire tumor plus edema.
  • 10:55You can see on spectroscopy
  • 10:56the areas that are, this
  • 10:58is a low grade glioma.
  • 10:59You can see the areas
  • 11:00that are, there are more
  • 11:02involved in terms of
  • 11:04metabolism.
  • 11:06And then you can see
  • 11:07from,
  • 11:07the FET, the subset of
  • 11:10that tumor,
  • 11:11there is the more aggressive
  • 11:12component.
  • 11:14And that, you know, can
  • 11:15be one way to look
  • 11:16at image guided
  • 11:18radiotherapy
  • 11:19based on the biology as
  • 11:20opposed to, a hunch.
  • 11:23And you can see on
  • 11:24the on the right side
  • 11:25the the signature of these,
  • 11:26which are, on the MRSI,
  • 11:28which are different.
  • 11:29This is all done with,
  • 11:31this is work done by
  • 11:32Chao Mang, and a grant
  • 11:33he just started, with, Proton.
  • 11:37And now we can do
  • 11:38also,
  • 11:39deuteron. This is the work
  • 11:40of, Hank Fader and, Robin
  • 11:42de Graaf here at Yale.
  • 11:43We're, now we're looking at
  • 11:45the deuterium metabolic imaging. So
  • 11:47we're not looking at the
  • 11:48h one now. We're looking
  • 11:49at the h two here.
  • 11:51Just that number changes, but
  • 11:52a lot of things go
  • 11:53with that. And we can
  • 11:54look now at a three
  • 11:55d map of the glucose
  • 11:57deuterium metabolic imaging, the glutamate,
  • 11:59glutamine,
  • 12:01all of those in
  • 12:03in a human four t
  • 12:04scanner.
  • 12:05This is again,
  • 12:07a this is now a
  • 12:08little larger
  • 12:09voxel. Now we're talking about
  • 12:11a two centimeter isotropic,
  • 12:13in a thirty minute. But
  • 12:14remember, this is now
  • 12:16a deuterium that we're imaging,
  • 12:17not pro, proton
  • 12:21water.
  • 12:22So signal is definitely less.
  • 12:24The the way we do
  • 12:25this is no different than
  • 12:26what you're used to with,
  • 12:27glucose,
  • 12:28FPG. You would,
  • 12:30you know, instead of having
  • 12:31an IV injection, you would
  • 12:32drink some,
  • 12:34drink some glucose,
  • 12:35wait for seventy five minutes,
  • 12:37and then, your image for
  • 12:38forty five minutes.
  • 12:40Here's some of the typical
  • 12:41image you'd see. You would
  • 12:42see this is one of
  • 12:43series of twenty three patients
  • 12:45with brain tumors that have
  • 12:46been,
  • 12:47imaged now by,
  • 12:49by Hank,
  • 12:51where, you could interleave your
  • 12:53MR with your, deuterium metabolic
  • 12:56imaging. So you'd have both
  • 12:57about the same time.
  • 12:59It's a forty five minute
  • 13:00protocol. So it's still a
  • 13:02little long, but it's not,
  • 13:04you know, impossible to do.
  • 13:06And I'd like to draw
  • 13:06your attention to the to
  • 13:08the bottom where not only
  • 13:09you can see the glutamine,
  • 13:10glutamine, lactate, but the ratio
  • 13:11of lactate to glutamine is
  • 13:13actually an indicator of the
  • 13:14Warburg effect,
  • 13:16and that is indicative of
  • 13:17the aggressiveness of the primary
  • 13:19tumor. So we are getting
  • 13:21now more of a window
  • 13:22into the functionality of that
  • 13:24tumor as opposed to only
  • 13:25the appearance that we have
  • 13:26from the t two.
  • 13:28Last slide on MRSI is
  • 13:30to show you that we
  • 13:31can also look at the,
  • 13:32choline metabolism in these brain
  • 13:34tumors.
  • 13:35As you know, choline is
  • 13:37a precursor to acetylcholine
  • 13:38neurotransmitter in the brain, but
  • 13:40it's also a key component
  • 13:41of the bio membrane.
  • 13:43And, the choline transport is
  • 13:46and the metabolism is regulated.
  • 13:48It's upregulated in many cancers,
  • 13:49so,
  • 13:50especially brain tumors.
  • 13:52So the idea here is,
  • 13:54that by, you know, you
  • 13:56can have it,
  • 13:58either IV or, you can
  • 13:59drink it. And in both
  • 14:01cases,
  • 14:02you can see that,
  • 14:05seventy five minutes later, you
  • 14:06you have a signal
  • 14:08that is now,
  • 14:10the area of,
  • 14:11choline metabolism in in the
  • 14:13brain. So, and this is
  • 14:15now without an amino acid
  • 14:17PET injection. So you see
  • 14:18that there's there's a lot
  • 14:19of, duality here in what
  • 14:21we're doing, and doing one
  • 14:22or the other allows you
  • 14:23to see more.
  • 14:25Now I hope you've noticed
  • 14:26that the images I've shown
  • 14:27you of the brain were
  • 14:28very poor quality. If you
  • 14:30didn't, you're very polite. But
  • 14:32but these are the kind
  • 14:33of images that we're all
  • 14:35used to seeing in PET.
  • 14:37Those are images at a
  • 14:38resolution of about, four millimeters,
  • 14:40five millimeters. So for a
  • 14:42volume, that would be a
  • 14:43hundred and twenty five millimeter
  • 14:45cubed.
  • 14:46What I'm gonna show you
  • 14:47next are images now at
  • 14:49two millimeters or one point
  • 14:50five millimeters. So,
  • 14:52you know, something around six
  • 14:54millimeter cubed. So about
  • 14:56twenty five times a better
  • 14:57spatial resolution.
  • 14:58This is,
  • 15:00a new brain system, a
  • 15:01neuro explorer that has just
  • 15:02been installed at Yale,
  • 15:04funded by a u o
  • 15:05one led by Rich Carson
  • 15:07at Yale and United Imaging,
  • 15:10health in Houston.
  • 15:12And the idea here is
  • 15:13to go with a very
  • 15:14small crystal
  • 15:16with a very large,
  • 15:18coverage of the brain,
  • 15:20very unusual to what we
  • 15:21do today. This is about
  • 15:22fifty centimeters of axial coverage.
  • 15:25And the reason is
  • 15:27we would like to get
  • 15:28the highest sensitivity possible,
  • 15:30and I'll show you some
  • 15:31clinical implications or benefits of
  • 15:33that.
  • 15:35You can think of that
  • 15:36both in terms of, well,
  • 15:36you could inject a lot
  • 15:38less,
  • 15:38but also in terms of
  • 15:40you can see signal in
  • 15:41the marginal lesion detectability, what
  • 15:43we call marginal lesion detectability.
  • 15:45Those tumors, they are the
  • 15:46the hardest to see because
  • 15:47the contrast to background is
  • 15:48the the lowest.
  • 15:50And now you can start
  • 15:51seeing things we're we're not
  • 15:52used to seeing. And I'll
  • 15:53show you some examples of
  • 15:54both.
  • 15:54So I'm gonna start with,
  • 15:56like, maybe the second slide
  • 15:57of a normal,
  • 15:59no cancer,
  • 16:00but to drive the message
  • 16:02of what high resolution and
  • 16:04sensitivity buys you.
  • 16:06So for those who are,
  • 16:07fans of astronomy, think of
  • 16:09the HRT, which has been
  • 16:10the best system we've had
  • 16:12as the Hubble Telescope.
  • 16:13And that is still much
  • 16:14better than a regular, brain
  • 16:16scanner. Those images actually are
  • 16:17better than the ones you
  • 16:18see in the clinic.
  • 16:19And this is the neuro
  • 16:20explorer, which think of it
  • 16:21as maybe the Webb telescope.
  • 16:23And, here you have a
  • 16:24twenty five
  • 16:26fold better image resolution and,
  • 16:29twenty fold,
  • 16:30sensitivity.
  • 16:31So now we're starting to
  • 16:32see cortical ribbon. We're starting
  • 16:33to see central,
  • 16:35brain structures. We're seeing the
  • 16:36horn of the chordate nucleus,
  • 16:37the basal ganglia, things that
  • 16:39until now we we know
  • 16:40about in neuroanatomy, but in
  • 16:41PET, we don't usually see.
  • 16:43So what does that do
  • 16:44to us in oncology? So
  • 16:46here's an example of,
  • 16:49another brain tumor that,
  • 16:51is again
  • 16:53well well characterized on FLAIR.
  • 16:55But what I would like
  • 16:56to show you is the
  • 16:57FDG scan of that patient,
  • 16:59both on a clinical
  • 17:01scanner
  • 17:02and on the neuro explorer.
  • 17:03And I do hope
  • 17:05yes. I can see it.
  • 17:06I hope you see it
  • 17:07over there. Can you see
  • 17:09my cursor when I'm moving
  • 17:10over there? You can. Oh,
  • 17:11good. Because usually by the
  • 17:13end of the talk is
  • 17:13when the speaker asks, can
  • 17:14you see my cursor? So
  • 17:16at least at least I
  • 17:17asked only twenty one slides
  • 17:19into my seven hundred slides.
  • 17:21So I hope you can
  • 17:22see the lesion here.
  • 17:24And unless you're,
  • 17:27really really good, I don't
  • 17:28think you can see it
  • 17:28here.
  • 17:30That's a good example of
  • 17:31what a gain in sensitivity
  • 17:33buys you,
  • 17:34when, imaging with PET.
  • 17:38Alright.
  • 17:39So we're gonna move to
  • 17:40sarcomas.
  • 17:41And,
  • 17:42here I'm gonna try to
  • 17:44show you some examples,
  • 17:46of what PET and a
  • 17:47Marsh Petrosky can do together.
  • 17:49You Starting to see a
  • 17:50theme. This started with, a
  • 17:52grant we were in our
  • 17:53own, we're working on where,
  • 17:55basically, we had asked a
  • 17:56question for many of the
  • 17:57sarcomas,
  • 17:59who,
  • 17:59for many of the patients
  • 18:00who refuse to have surgery.
  • 18:02We we do have about
  • 18:04thirty percent of patients who
  • 18:05say, no. I wanna forego
  • 18:06surgery because I wanna go
  • 18:07back to work,
  • 18:08less than a year later.
  • 18:10There is a risk of
  • 18:11recurrence. And so there are
  • 18:12two questions. The first one,
  • 18:14well,
  • 18:15can we tell if we've
  • 18:16treated everything or not? And
  • 18:17two, if there is recurrence,
  • 18:19are you able to tell,
  • 18:21early enough?
  • 18:22And the answer to two
  • 18:23of the those two is
  • 18:25yes. I hope to I
  • 18:26hope I'll be able to
  • 18:26convince you of that.
  • 18:28Just know that from the
  • 18:29radiation oncology side, and there's
  • 18:31no critique by no
  • 18:33mean, the current consensus is
  • 18:35quite crude. Basically, it's, you
  • 18:36know, you take a three
  • 18:37and a half centimeter
  • 18:38longitudinal, one and a half
  • 18:39centimeter radial, blast that, and
  • 18:41you're good.
  • 18:43And the question is, well,
  • 18:44is that really necessary?
  • 18:46And again, this is not
  • 18:47at all we we work
  • 18:48very, very closely with many
  • 18:50of our radiation oncologists. This
  • 18:51is not at all by
  • 18:51any mean, a criticism, but
  • 18:53these are, what we call
  • 18:55gross target volume. So that's
  • 18:56what we've decided is the
  • 18:58tumor,
  • 18:59that was delineated by multiple,
  • 19:01radiation oncologists and okay. And
  • 19:03maybe a couple of residents.
  • 19:04And the message we're trying
  • 19:06to convey here is that,
  • 19:09depending on who's doing
  • 19:12what at what time of
  • 19:12the day, your contour will
  • 19:14vary.
  • 19:16So don't hope for a
  • 19:17very reproducible
  • 19:19treatment that you'd have the
  • 19:20same way if two physicians
  • 19:22did the same.
  • 19:23And the message from that
  • 19:24is not, oh, you shouldn't
  • 19:25do it. The message of
  • 19:26that is, is there a
  • 19:27way we could reduce that
  • 19:28variability? And I'll show you,
  • 19:30that yes. We can. Alright.
  • 19:31So let's start with the
  • 19:32first question. So here's one
  • 19:33example.
  • 19:34This is a six year
  • 19:35old female with a soft
  • 19:37tissue circum of the right
  • 19:38leg.
  • 19:40This is your t two,
  • 19:42enhanced MR. So based on
  • 19:43that, all of this would
  • 19:44be treated because some of
  • 19:45it is tumor, some of
  • 19:46it is edema. We don't
  • 19:47know what is what.
  • 19:48This is your pet signature.
  • 19:50We see that it's mainly
  • 19:51this area that is actually,
  • 19:53active and the rest is
  • 19:54not.
  • 19:57Oh, somebody's trying to do
  • 19:58something else while listening.
  • 20:01And,
  • 20:02of course, on pathology that
  • 20:04is confirmed, this is the
  • 20:05area that is, the the
  • 20:06tumor and on, on a
  • 20:08pathology, it's, that's confirmed. Now
  • 20:10don't take my word for
  • 20:11it. If this was my
  • 20:12my grandmother, I would say
  • 20:13no treat the whole thing.
  • 20:15But,
  • 20:16but doing this enough times,
  • 20:18now we've seen that, you
  • 20:19know, every time every time
  • 20:21what you see on FDG
  • 20:22is what you see on
  • 20:22pathology.
  • 20:23So, yes, you could, you
  • 20:25know, use PET to guide
  • 20:26your treatment.
  • 20:27And the second question was,
  • 20:28well, after treatment now, can
  • 20:30can pet help me with
  • 20:31determining if determining if there
  • 20:33is any remaining? And the
  • 20:34answer is no.
  • 20:35Because, yes, in this case,
  • 20:37for example, you see there
  • 20:38is signal here,
  • 20:40but we don't know if
  • 20:41this is tumor or if
  • 20:43this is simply
  • 20:45inflammation post treatment.
  • 20:47MR spectroscopy, on the other
  • 20:48hand, can help you. So
  • 20:50here's, an example, that that
  • 20:52same example where
  • 20:54this is the healthy contralateral
  • 20:56leg where you see the
  • 20:57choline protein ratio is normal.
  • 21:00This is the,
  • 21:01tumor where you see that
  • 21:02the choline protein ratio is
  • 21:04overtly abnormal.
  • 21:05And in that area, you
  • 21:06didn't know what to do
  • 21:07with PET. Well, the ratio
  • 21:09is normal and sure enough,
  • 21:10a month later that has
  • 21:11resolved.
  • 21:12So you see that using
  • 21:14both, has a value because,
  • 21:17the pet can guide you,
  • 21:18but I can't tell you
  • 21:19in this case whether it's
  • 21:20a remaining tumor,
  • 21:21or not, and, a Mars
  • 21:23spectroscopy can.
  • 21:24Now this was,
  • 21:26easier said than done. What
  • 21:27we actually did, this is
  • 21:29the ugly part of it,
  • 21:30is in order to map
  • 21:32absolutely
  • 21:33and be absolutely sure what
  • 21:34is where,
  • 21:35I showed you all look
  • 21:36this the path and pathology
  • 21:38agrees. What we did really
  • 21:40was,
  • 21:41we did an MR. We
  • 21:42did a three d printing
  • 21:43of the tumor
  • 21:44and of its surrounding.
  • 21:45When the tumor was excised,
  • 21:48it was taken in
  • 21:50and frozen in this mold,
  • 21:52then it was sliced.
  • 21:54We had to pay a
  • 21:55lot of chocolate and champagne
  • 21:57and drinks for the pathologist
  • 21:59who agreed to do not
  • 22:00two slides, but forty slides
  • 22:02out of one slice.
  • 22:04And now you have your
  • 22:07pathology and your pet absolutely
  • 22:09in the same reference.
  • 22:11And and now you have
  • 22:12a validation slide by slide.
  • 22:14This is very important because
  • 22:15if we're gonna do any
  • 22:16deep learning, we need that.
  • 22:18And I'll show you some
  • 22:19of what we've done with
  • 22:20this. It is very hard,
  • 22:22very lengthy, but there is
  • 22:23no shortcuts if you really
  • 22:25wanna do this, the right
  • 22:26way.
  • 22:28Remember I showed you a
  • 22:29slide of big variability in
  • 22:30the GTV.
  • 22:32We have been working on
  • 22:33this
  • 22:34not to replace the radiation
  • 22:36oncologist,
  • 22:37but to provide the radiation
  • 22:38oncologist with a starting point
  • 22:40so they save time.
  • 22:41In the US, you know,
  • 22:42we have radiation oncologist who
  • 22:44are specialized in head and
  • 22:45neck, in sarcomas, in
  • 22:47CNS.
  • 22:48In many parts of the
  • 22:49world and,
  • 22:50including Germany, France, China, many
  • 22:52other countries,
  • 22:53they do all parts, all
  • 22:55body parts.
  • 22:56So when you're starting, it's
  • 22:57really nice to have something
  • 22:58that can be a a
  • 22:59place you can start from
  • 23:00and adjust. It saves you
  • 23:02time. It increases your
  • 23:04productivity,
  • 23:05and it's a good,
  • 23:07training tool. So the idea
  • 23:08here was,
  • 23:10not to learn from what
  • 23:11one radiation oncologist can draw
  • 23:13in terms of gross target
  • 23:14volume or clinical target volume,
  • 23:16but to have many of
  • 23:17them do the same thing
  • 23:19and have the neural network
  • 23:21learn from all of those
  • 23:23as opposed to learning from
  • 23:25one contour.
  • 23:26This is a lot harder
  • 23:27because now you don't have
  • 23:28a truth. You have more
  • 23:30of a level of confidence
  • 23:31based on where they agree.
  • 23:33It takes a lot longer
  • 23:34to learn. You need more
  • 23:35data. And you're not gonna
  • 23:37be as accurate
  • 23:38as if you had one
  • 23:40traditional colleges because what you're
  • 23:41learning is the variability.
  • 23:44However,
  • 23:45that will allow you to
  • 23:45be a lot more robust.
  • 23:47Meaning,
  • 23:48if you go to a
  • 23:49different hospital,
  • 23:50if you go to a
  • 23:51different setting, you'll still be
  • 23:52fine because what you've learned
  • 23:54is a confidence level as
  • 23:55opposed to a black and
  • 23:56white. So instead of having
  • 23:57one contour, what you will
  • 23:58have at the end, what
  • 23:59I'm showing you here is
  • 24:00a confidence level. So let
  • 24:02me show you some results
  • 24:03of how well we do
  • 24:04with this.
  • 24:05These are
  • 24:07patients that were never presented
  • 24:08to the network until validation
  • 24:10where you can see,
  • 24:11that there's a very good
  • 24:13agreement between what the consensus
  • 24:16between,
  • 24:16the radiation oncologist is, or
  • 24:19I should say therapeutic radiologist,
  • 24:21at Yale. And, what the
  • 24:23level of confidence you have
  • 24:25from the network. The hotter
  • 24:26the yellower, the hotter. And,
  • 24:29and the orangier,
  • 24:30the less. I should have
  • 24:31picked different colors, I guess.
  • 24:33And you see that the,
  • 24:34accuracy is not, you know,
  • 24:35very good. It's in the
  • 24:36eighty six percent, which is
  • 24:37where we expected. It's not
  • 24:39ninety nine percent. And, frankly,
  • 24:40I don't believe in network
  • 24:41that does ninety nine percent
  • 24:42because you take it to
  • 24:43a different location, it won't
  • 24:45do as well. However,
  • 24:47we are capturing very well
  • 24:48the inter observer variability
  • 24:50and, from the CT, the
  • 24:51clinical target volume, we're doing
  • 24:53also very well,
  • 24:54with the compared to what
  • 24:55was predicted.
  • 24:57This is an example showing
  • 24:58you now that if you
  • 24:59did that instead of doing
  • 25:00it only on CT, if
  • 25:01you did with PET,
  • 25:02you reduce your variability, you
  • 25:04increase your reproducibility, which is
  • 25:06what you would expect.
  • 25:07And this is showing you
  • 25:09that,
  • 25:09you know, we can do
  • 25:10this now in a more
  • 25:12sophisticated way with diffusion networks,
  • 25:15but the resolution,
  • 25:16is about the same. We're
  • 25:17still in the eighty eight
  • 25:18percent. It's just that we're
  • 25:19now more resilient to, to
  • 25:21noise.
  • 25:23Alright. This has shown you
  • 25:24that we can do this
  • 25:25also for the clinical target
  • 25:26volume, not just for the
  • 25:27gross target volume.
  • 25:29I'd like to move now
  • 25:30to head and neck. We're
  • 25:31excited that we're starting a
  • 25:33new, project now looking at
  • 25:35this in head and neck
  • 25:36as opposed to sarcomas,
  • 25:38where we're looking again, how
  • 25:39is the contribution from PETCT
  • 25:41or taken together, and how
  • 25:43well can we do?
  • 25:45I hope you can see
  • 25:46here that we can delineate
  • 25:47very accurately the, the tumor.
  • 25:50And, more importantly, I wanna
  • 25:52show you what you can
  • 25:53do now if you have
  • 25:55a much better sensitivity with
  • 25:56your PET scan, again, compared
  • 25:58to what we're used to.
  • 26:00So those are the same,
  • 26:01Webb Telescope images.
  • 26:03Now this is the work
  • 26:04of, the creator Inaga in
  • 26:06our group who is looking
  • 26:07at,
  • 26:08head and neck cancer within
  • 26:09our explorer. So much higher
  • 26:11sensitivity,
  • 26:12much higher resolution,
  • 26:14same patients scanned on our
  • 26:16clinical
  • 26:17vision
  • 26:18and our,
  • 26:20research for now, NeuroExplorer, which
  • 26:22is FDA approved by the
  • 26:23way. Some of those are
  • 26:24very obvious. You see the
  • 26:26lesion very well in both.
  • 26:27What I would like you
  • 26:28to notice is, one, that
  • 26:30the lesion delineation is clearer
  • 26:33and the contrast is higher.
  • 26:34That is not a higher,
  • 26:36glycolytic rate of the tumor.
  • 26:38It's exactly the same tumor.
  • 26:39It's just that we have
  • 26:40less partial volume effect. That's
  • 26:42all.
  • 26:43These are lymph nodes in
  • 26:44the left neck where you
  • 26:45see,
  • 26:46same story.
  • 26:48And in the base of
  • 26:49the tongue, same story again,
  • 26:50where you have a much
  • 26:51better deniation of the anatomy
  • 26:53and of the tumor.
  • 26:56This is a lymph node
  • 26:57in the left neck, and
  • 26:58I think I have one.
  • 26:59Yeah. This one I like.
  • 27:00And this is, again,
  • 27:02lymph node left neck, but
  • 27:04what I draw what I
  • 27:04would draw your attention is
  • 27:06to this component of the
  • 27:07tumor, which is barely visible
  • 27:09and clearly visible on,
  • 27:12on the nurse core.
  • 27:15Okay.
  • 27:16I think you've seen enough
  • 27:17good pictures. Let's move to
  • 27:18the next, some basic science.
  • 27:20Now we're gonna move to,
  • 27:22more basic science in terms
  • 27:24of,
  • 27:26a new radio
  • 27:27a a new a new
  • 27:29target.
  • 27:29What we're looking here at
  • 27:31is measuring the membrane potential.
  • 27:33And you can think of
  • 27:34the membrane potential as the
  • 27:35battery,
  • 27:36of life for the cell
  • 27:37because that's the that's what
  • 27:38the mitochondria uses,
  • 27:41in its role as an
  • 27:42energy plant,
  • 27:43so as a power plant.
  • 27:45So that's what we use
  • 27:46to convert our, ADP to
  • 27:48ATP,
  • 27:49and
  • 27:50this is the canary in
  • 27:51the mine. It is affected
  • 27:53very early on,
  • 27:55anytime there is a change
  • 27:57in the reactive oxygen species.
  • 27:59So you'll see this affected
  • 28:01long before
  • 28:02other more,
  • 28:04anatomical
  • 28:05or functional. I'll show you
  • 28:06some examples.
  • 28:09Parameters we measure usually are
  • 28:11are affected.
  • 28:12Okay. So
  • 28:14let let's, let's dig into
  • 28:15this. This has been known
  • 28:17for for a long time,
  • 28:18as something you can measure
  • 28:20with treated compounds
  • 28:22in dead in
  • 28:24in in cells but in
  • 28:24dead people.
  • 28:25The idea here was to
  • 28:26do this in vivo in
  • 28:28living humans. So
  • 28:29we labeled,
  • 28:31the tryphalan phosphonium with f
  • 28:32eighteen, and then,
  • 28:34we set out to measure
  • 28:36that membrane potential, which would
  • 28:37be basically if you had
  • 28:38a
  • 28:39nano electrode inside the cell
  • 28:41and one outside the cell,
  • 28:42that would be the voltage
  • 28:43difference you would see.
  • 28:45That's what we're trying to
  • 28:46measure.
  • 28:47I'll spare you the kinetic
  • 28:49modeling, which is what a
  • 28:50lot of us spend our
  • 28:51time doing.
  • 28:52But I wanna I wanna
  • 28:53just point out that what
  • 28:54you're measuring here is the,
  • 28:57voltage in millivolts,
  • 28:59not arbitrary units.
  • 29:02That was published in twenty
  • 29:03twenty, and here's some of
  • 29:04the applications. The one I'll
  • 29:05show you obviously is the
  • 29:07one that has to do
  • 29:07with cancer.
  • 29:09So,
  • 29:09what we look at is
  • 29:11cardiotoxicity,
  • 29:12but before we go there,
  • 29:13I would like to show
  • 29:14you this graph to show
  • 29:15you that
  • 29:16the membrane potential measurement is
  • 29:18incredibly
  • 29:19well preserved in humans.
  • 29:21And rightfully so because it's,
  • 29:23as I told you, the
  • 29:23canary in the mind. So
  • 29:25this is very valuable because
  • 29:26that means that when we're
  • 29:27gonna set out to imaging
  • 29:29that in patients versus healthy
  • 29:31controls,
  • 29:32the difference will be due
  • 29:33to the disease, not to
  • 29:34variability in the patients. Because
  • 29:36this is many, many patients
  • 29:37that were scanned, and you
  • 29:38can see that they're plotted
  • 29:39here and they're all about
  • 29:41the same.
  • 29:43Alright. So cardiotoxicity,
  • 29:44why are we doing this?
  • 29:46As you know,
  • 29:47patients who receive doxorubicin
  • 29:49in breast cancer, for example,
  • 29:52they,
  • 29:52they have serious side effects
  • 29:54that not all not always
  • 29:56manifest immediately. Sometimes it's
  • 30:00months and years later. And
  • 30:02these can be very healthy
  • 30:03otherwise patients. So there's
  • 30:05very little in terms of
  • 30:06predictive,
  • 30:08prediction of who's gonna
  • 30:10go for,
  • 30:12cell death and heart failure
  • 30:13other doctor Rubinstein versus who's
  • 30:14not going to.
  • 30:16One of the measurements we
  • 30:17do is the left ventricle
  • 30:18ejection fraction,
  • 30:20but that's a little bit
  • 30:22late. By the time you
  • 30:24see the ejection fraction changing,
  • 30:26a lot of the harm
  • 30:27has been done. And I'll
  • 30:28show you in the experimental
  • 30:29model that
  • 30:30that's the case. So the
  • 30:32idea here is, is there
  • 30:34a way we could predict
  • 30:36long before ejection fraction has,
  • 30:39started to telling us there's
  • 30:40something wrong,
  • 30:41that, you know,
  • 30:43it's too late?
  • 30:44Alright. And that's where
  • 30:45we would like to,
  • 30:47intervene with,
  • 30:49membrane potential PET imaging.
  • 30:51Alright.
  • 30:53Let's see. First, I'm gonna
  • 30:54show you some acute,
  • 30:55examples because,
  • 30:57in physiology, you always have
  • 30:59to show
  • 31:00effect in in real time
  • 31:01before we go to more,
  • 31:03more long term, and I'll
  • 31:04then I'll show you the,
  • 31:06chronic care model. So in
  • 31:07the acute model,
  • 31:08these are pigs that are,
  • 31:10I'm showing here results in
  • 31:11eight pigs. They're you know,
  • 31:12we have an intervention. We
  • 31:13go into the LAD. We
  • 31:14inject,
  • 31:16acutely
  • 31:17docservicin in the LAD, and
  • 31:18we expect to see
  • 31:20a drop in the membrane
  • 31:21potential transiently
  • 31:24in the anterolateral wall, you
  • 31:25know, insert in the anterior
  • 31:26wall and septal wall, but
  • 31:28not in the inferior wall
  • 31:29because we didn't inject anything
  • 31:31in the right circumflex. So
  • 31:32the right circumflex serves as
  • 31:34the,
  • 31:35control in each in each
  • 31:36animal and you should see
  • 31:38in this area a drop
  • 31:39the membrane potential in millivolts
  • 31:41and this area no drop
  • 31:42and that's exactly what you
  • 31:44see. Alright. That's the chronic
  • 31:46model. And when we form
  • 31:47the images of these, again,
  • 31:49these units here are in
  • 31:50millivolts. You see minus one
  • 31:51twenty millivolts and in the
  • 31:53anterior and septal, there is
  • 31:54a drop, but in the
  • 31:55inferior wall, there's none.
  • 31:57Then we move to the
  • 31:58chronic setting. That's the more
  • 31:59complicated study. Now we're treating
  • 32:01pigs as, patients who have
  • 32:03a breast cancer,
  • 32:05over, several months.
  • 32:07And
  • 32:08the figure I would like
  • 32:09you to leave, if there's
  • 32:10one figure to leave for
  • 32:11doc cardiotoxicity with is this.
  • 32:13This is the membrane potential
  • 32:16of those pigs over time,
  • 32:17and you can see that
  • 32:18this was before treatment.
  • 32:20You see how it drops
  • 32:23very quickly?
  • 32:24Whereas the left ventricle ejection
  • 32:26fraction stays on for a
  • 32:27while
  • 32:28before it drops.
  • 32:30What is interesting is that
  • 32:31when we start treatment,
  • 32:34you know, the
  • 32:36the ventricle ejection fraction drug
  • 32:37goes up again very quickly.
  • 32:39Whereas with the,
  • 32:41sorry, the membrane pressure goes
  • 32:43up quickly whereas the ejection
  • 32:44fraction doesn't. So this is
  • 32:46a canary in the mind
  • 32:47that allows you, in this
  • 32:49case, after six cycles, to
  • 32:50determine where you are in
  • 32:51terms of,
  • 32:53in terms of,
  • 32:55viability of the tissue. And
  • 32:57this is a study that
  • 32:58we will be starting here
  • 32:59at Yale,
  • 33:00next month.
  • 33:02Alright. Last part of my
  • 33:03talk, I would like to
  • 33:04cover some of the,
  • 33:06again, more exploratory in, imaging
  • 33:08immune response with PET. And
  • 33:10we're gonna start with Feraheme,
  • 33:11which is an MR contrast
  • 33:12agent. That's fermoxetil. It's an
  • 33:14iron particle that is actually
  • 33:15FDA approved for, anemia.
  • 33:18Because, over, over time the,
  • 33:21the bioavailable iron, the nano
  • 33:24particle core dissolves and the
  • 33:25bioavailable iron becomes exposed and
  • 33:27that's a treatment for anemia
  • 33:28that is approved. But it
  • 33:29started as an MR contrast,
  • 33:31and there have been several
  • 33:32clinical trials done in that
  • 33:34space because,
  • 33:35you know, it it will
  • 33:36track lymph nodes and you
  • 33:37can see lymph node involvement.
  • 33:39The only problem is because
  • 33:41it's an MR contrast, you
  • 33:42have a few minutes to
  • 33:43see it. And after ten,
  • 33:44fifteen minutes, the signal is
  • 33:45gone. So the idea was,
  • 33:46well, if we label this,
  • 33:47and in this case, I'll
  • 33:48spare you the radiochemistry, but
  • 33:49it's basically a chelation where
  • 33:51you heat,
  • 33:52the core and then, the
  • 33:53the zirconium
  • 33:55eighty nine goes into the
  • 33:56core
  • 33:57of the, fermoxetal
  • 33:58and stays there forever.
  • 34:00If we label that, we
  • 34:01could follow then for a
  • 34:02long time,
  • 34:04that,
  • 34:05that, compound as it,
  • 34:08distributes in the body.
  • 34:10And, this is where we
  • 34:11were very very surprised.
  • 34:13This is an example in
  • 34:14an animal that had,
  • 34:16a skin lesion.
  • 34:18This is a nonhuman primate
  • 34:19where, now you see the
  • 34:21time is two hundred hours.
  • 34:22We're following for a long
  • 34:23time because zirconium eighty nine
  • 34:24allows you, to follow the
  • 34:26enemy.
  • 34:27You can see that the
  • 34:28uptake in the ipsilateral lymph
  • 34:30nodes was going up over
  • 34:31time,
  • 34:32but there is no circulating
  • 34:34activity anymore. You know, the
  • 34:35activity after a few minutes
  • 34:37has distributed, and that's it.
  • 34:39So this is not circulating
  • 34:40activity. This is
  • 34:42active trafficking of monocytes.
  • 34:45And that was our first,
  • 34:46discovery in this, the totally
  • 34:48scientifically because we we didn't
  • 34:49expect to see that over
  • 34:50time.
  • 34:52So I'll show you now
  • 34:53another example of,
  • 34:55what we can do with
  • 34:56this.
  • 34:57Those of you old enough
  • 34:58to know white blood cell
  • 34:59imaging, Indian white blood cell,
  • 35:01remember how we draw bloods
  • 35:02and then he labeled Indian
  • 35:03and,
  • 35:04well, this is a spin
  • 35:05on that. No pun intended.
  • 35:07But now we're,
  • 35:09we draw the blood and
  • 35:10then we isolate by, you
  • 35:12know, by facts the t
  • 35:13cells and the b cells.
  • 35:14And we can isolate the
  • 35:16monocytes also,
  • 35:17by buffy coat extraction.
  • 35:19And then you label those
  • 35:21b cells or t cells
  • 35:22with the zirconium for a
  • 35:23hem, then you reinject them.
  • 35:25And now what you see
  • 35:26is, this is an EAE
  • 35:27model, where we're labeling the
  • 35:29b cells. And you can
  • 35:30see that,
  • 35:31when, you have EAE induction,
  • 35:33you do see,
  • 35:34uptake in the, area of
  • 35:36lesion. Whereas when, you don't
  • 35:38have,
  • 35:40the EAE model, when you
  • 35:42when you have a sham
  • 35:43induction without labeling of the
  • 35:44b cells, you don't see,
  • 35:46uptake in that area. And
  • 35:47the same with the immunomodulator
  • 35:49with the t cells. You
  • 35:50see that, with the immunomodulator,
  • 35:52you have a drop when
  • 35:54you're doing the t cells.
  • 35:55Whereas when you're doing the
  • 35:56sham or n p injection,
  • 35:58you don't see that drop.
  • 35:59So this is to peak
  • 36:01your curiosity about what you
  • 36:03could do now,
  • 36:04imaging t cells and b
  • 36:05cells in the body,
  • 36:07as opposed to and you
  • 36:08can see if they're going
  • 36:09to the spleen, well, nothing's
  • 36:10happening or they're going to
  • 36:11the tumor. Well, that's a
  • 36:12real, immune
  • 36:15recruitment.
  • 36:16This is a compound that
  • 36:17we hope to bring to
  • 36:18man here at Yale.
  • 36:20It is part of,
  • 36:21a large study where we've
  • 36:23done now the dosimetry. It
  • 36:24is, all very promising.
  • 36:26Really chemistry,
  • 36:28purity is also very good.
  • 36:30And we're hoping that, you
  • 36:31know, within a year from
  • 36:32now, this will be in
  • 36:33humans here, with an IND.
  • 36:36Alright. I'd like to close.
  • 36:37I have still a few
  • 36:38minutes. I'd like to close
  • 36:39with,
  • 36:40the piece de resistance, which
  • 36:42is
  • 36:43the rhinostics and the role
  • 36:44of pet inspect in there.
  • 36:46So for those of you
  • 36:47who,
  • 36:48you know, don't know the
  • 36:49rhinostics,
  • 36:51the idea is
  • 36:52that said in words, you
  • 36:54could see what you treat
  • 36:55and you could treat what
  • 36:56you see.
  • 36:57It is something that we
  • 36:58don't often have the luxury
  • 37:00of with chemotherapy
  • 37:02where
  • 37:03you don't see what you're
  • 37:04treating. You you treat and
  • 37:05then you're treating blind. So
  • 37:06the idea basically is that
  • 37:09we would use a PET
  • 37:10agent, and we'll talk in
  • 37:11a minute about agents, but
  • 37:13that is going specifically to
  • 37:14a tumor to see if
  • 37:15you have enough signal
  • 37:16to justify treatment,
  • 37:18through a radiopharmaceutical
  • 37:19treatment.
  • 37:20If you do, then you
  • 37:21have your radiopharmaceutical
  • 37:22treatment, and Pam is doing
  • 37:24a lot of this in
  • 37:25NET.
  • 37:26And then, at the end,
  • 37:27you could even image and
  • 37:28see how well have you
  • 37:29done.
  • 37:30That's the general idea.
  • 37:32What we're interested in doing,
  • 37:33and we're very excited, that's
  • 37:34another project that we'll be
  • 37:36starting,
  • 37:37is that what you could
  • 37:38do is not just
  • 37:40do your
  • 37:41pretreatment,
  • 37:42in this case, Lutetium,
  • 37:44and then Pam told me
  • 37:45we've just done our first
  • 37:46alpha last week.
  • 37:48But for both of them,
  • 37:49it's the same idea. You
  • 37:50don't do your
  • 37:52pretreatment imaging. You say, yes.
  • 37:53There's enough uptake. Well
  • 37:55and then we do our
  • 37:56post treatment.
  • 37:57We've done well. What we
  • 37:59would like to do is
  • 38:00after every treatment,
  • 38:02image the patient to define
  • 38:05how our targets are responding,
  • 38:07what is our pharmacokinetics,
  • 38:09and what is our effective
  • 38:10dose. Because
  • 38:11there are some patients where
  • 38:12we will need to treat
  • 38:13more. And there are some
  • 38:15patients where
  • 38:16we don't need at all
  • 38:17the dose we're doing. We
  • 38:18can go a lot lower
  • 38:19and we still have the
  • 38:20same effect.
  • 38:21We have an opportunity to
  • 38:22do what we've done always
  • 38:23in iodine, for example, month
  • 38:24thirty one, to do a
  • 38:26a dosimetry
  • 38:27on the fly as the
  • 38:28patients are being,
  • 38:30given their two hundred milli
  • 38:32curiae of Lutetium.
  • 38:33And there's no cost to
  • 38:34it other than the imaging
  • 38:35piece because they are having
  • 38:37their Lutetium anyway. So that's
  • 38:39the idea with, NET with
  • 38:41the neuroendocrine tumors. You can
  • 38:42do the same, and and
  • 38:44you can define the refine
  • 38:45this at every treatment. So
  • 38:46So you can see cycle
  • 38:47one, cycle two, and then
  • 38:49you decide, well, you know,
  • 38:50we we can stop now.
  • 38:52Or, no, we're gonna have
  • 38:52to go one more cycle
  • 38:54as opposed to six cycles
  • 38:55of two hundred manicures.
  • 38:57You can do the same
  • 38:58in, prostate with the prostate
  • 39:00specific membrane antigen that we
  • 39:01can image. We can do
  • 39:03a gallium pre, and then
  • 39:04we can look at those
  • 39:06targets. What's the effective dose?
  • 39:08Do we need to go
  • 39:08up or down? And do
  • 39:10that one, two cycles and
  • 39:11then,
  • 39:13and then stop.
  • 39:14We can even go further.
  • 39:17What we can do, actually,
  • 39:18and this is the project
  • 39:19that I said we're excited
  • 39:20we're starting,
  • 39:21is we could do pre
  • 39:22imaging therapy
  • 39:24and only have one or
  • 39:25two of those scans, and
  • 39:26that is enough to predict,
  • 39:29you know,
  • 39:30whether you should act,
  • 39:34increase or decrease your dose
  • 39:36and and predict your outcome
  • 39:37from very few of those
  • 39:39studies. You don't need the
  • 39:40whole
  • 39:41study to predict that. So
  • 39:42the idea is gonna be
  • 39:43to looking at the very
  • 39:44early frames to very early
  • 39:46treatments to predict that because
  • 39:48more often than not, it
  • 39:49it is something you can
  • 39:50predict. It is challenging. It's
  • 39:52not simple, but I think
  • 39:52it's very valuable because,
  • 39:55you know, when we talk
  • 39:56about personalized medicine,
  • 39:58this is
  • 39:59personalized medicine by excellence. This
  • 40:01is like, you know, you
  • 40:01can't go more personalized than
  • 40:02that. It is your scan
  • 40:04that is defining your dose.
  • 40:06I would like to leave
  • 40:07you with two last slides
  • 40:08on something that is a
  • 40:09lot more, you know, also
  • 40:11coming, down. This is work
  • 40:13from Jason Kai who's looking
  • 40:15at a similar approach for,
  • 40:18prognostics
  • 40:19but for gliomas. And this
  • 40:20is looking at PARP.
  • 40:23Those of you who work
  • 40:23in PARP, you probably know
  • 40:24that PARP one inhibitors
  • 40:26are approved as treatment drugs
  • 40:28in many cancers, breast, pancreatic,
  • 40:30but also in brain. And
  • 40:31the idea here is to
  • 40:32label the PARP
  • 40:33and
  • 40:34see,
  • 40:36and see if we can
  • 40:37then use it for treatment.
  • 40:39What Jason has done is
  • 40:40the very first PARP
  • 40:42brain penetrant tracer. There has
  • 40:43been some that were not
  • 40:44brain penetrant.
  • 40:46Why that is important? Because
  • 40:47if it's not brain penetrant,
  • 40:48then you can't cross the
  • 40:49blood brain barrier and the
  • 40:50only time you see the
  • 40:51tumor is when there's breakage.
  • 40:52In this case, he has
  • 40:53shown that in the intact
  • 40:54brain barrier, you can image
  • 40:56that,
  • 40:57and see the tumor. And
  • 40:58the idea, of course, is
  • 40:59now well, he's done that
  • 41:01first with c eleven because
  • 41:02that's the easiest. Now we're
  • 41:03doing it with f eighteen,
  • 41:04and his plan is to
  • 41:05do that with,
  • 41:06acetylene,
  • 41:07because then you can, do
  • 41:09the same story. We we
  • 41:10talked about with neuroendocrine
  • 41:12and with
  • 41:15prostate. Now you can do
  • 41:16that in in the brain.
  • 41:17So that would be
  • 41:19a first.
  • 41:20And, it's, optimistic, but he's
  • 41:22hoping that in a year
  • 41:24or two from now, his
  • 41:24ID will be up and
  • 41:25running.
  • 41:26Alright. So,
  • 41:27I was asked to finish
  • 41:29with enough time for questions.
  • 41:30I hope this gave you
  • 41:32a good sense of what
  • 41:33can PedamR do PedamR do
  • 41:35for you.
  • 41:37I do hope, you know,
  • 41:38it gives you
  • 41:40some appetite for for some
  • 41:41of the imaging. I do
  • 41:43believe that imaging is not
  • 41:44meant to be just, you
  • 41:45know, show and tell, but
  • 41:46it has to guide the
  • 41:47treatment. If imaging doesn't guide
  • 41:49treatment,
  • 41:50for me, it's, you know,
  • 41:52a very,
  • 41:53you know, frustrating.
  • 41:55It's a nice exercise, but,
  • 41:57when we can guide treatment,
  • 41:58that's when we have a
  • 41:59role, that is meaningful. So
  • 42:00with that, I'd like to
  • 42:01thank you for the kind
  • 42:02invite to be here. And,
  • 42:03if you have any questions,
  • 42:04happy to take them.
  • 42:13Questions from the room. And
  • 42:15yes. Go ahead.
  • 42:17Yeah. That's a thought. You
  • 42:19talked about a lot of
  • 42:19things. I was curious. What
  • 42:22of of the things you
  • 42:23talked about, where do you
  • 42:24think you kinda where's the
  • 42:25lowest hanging fruit? What do
  • 42:26you think of this as
  • 42:27the kind of most immediate
  • 42:28potential to impact cancer care?
  • 42:31When it comes back. What
  • 42:32are you most excited about?
  • 42:33I hate this question because
  • 42:35each of those is one
  • 42:35of my kids, and whichever
  • 42:37I'm gonna say, a lot
  • 42:38of others are gonna be
  • 42:39upset. But,
  • 42:43I do think that in
  • 42:44the diagnostic space, there's a
  • 42:46lot of room.
  • 42:49I don't wanna sound pessimistic.
  • 42:51We are behind
  • 42:52we are behind the eyeball
  • 42:53here.
  • 42:55Most sites have already now,
  • 42:58very active diagnostic sites,
  • 43:00centers that are treating regularly
  • 43:03hundreds of patients. That's one
  • 43:04area of there's clear opportunity.
  • 43:07I understand some of the
  • 43:08caution of, well, you know,
  • 43:09a lot of these patients
  • 43:10recur, and that's right.
  • 43:12But it is the
  • 43:16you saw that example where,
  • 43:17you know, we learned by
  • 43:18by doing something, we realized,
  • 43:20oh my god. There's monocytes
  • 43:21being trafficked.
  • 43:23You're not gonna do the
  • 43:24alpha
  • 43:25treatments. You're not gonna do
  • 43:26the second generation
  • 43:27if you don't have a
  • 43:28site where you're doing a
  • 43:29lot of those patients.
  • 43:30So,
  • 43:32it is one area clearly
  • 43:33where there is
  • 43:34a huge impact,
  • 43:35for our patients. I understand
  • 43:37for now it's only two
  • 43:38cancers, not every cancer. But,
  • 43:40again, if you don't have
  • 43:41it for two, you're not
  • 43:42gonna have it for ten.
  • 43:43The other area I would
  • 43:44say is the spectroscopy part
  • 43:46because that is now very,
  • 43:48mature.
  • 43:49And, for the longest time,
  • 43:50we didn't do it because
  • 43:51it was too prohibitive in
  • 43:52terms of imaging. If you
  • 43:53need, you know, thirty minutes
  • 43:54to scan in addition to
  • 43:55everything you're doing in MR,
  • 43:57nobody's gonna agree to it
  • 43:58because spots are what they
  • 44:00are. But eight minutes is
  • 44:01feasible, and I think there's
  • 44:02there's a role there.
  • 44:04And I would say guiding
  • 44:05the treatment is something that
  • 44:07is very important because,
  • 44:10you know, it it in
  • 44:11in in no way it
  • 44:12is meant to be, oh,
  • 44:13well, no. You got it
  • 44:15wrong. It is that a
  • 44:16lot of times we don't
  • 44:16see on the on the
  • 44:17images
  • 44:18as much as we should
  • 44:19be. So I think the
  • 44:21treatment guidance is one area
  • 44:22that is promising.
  • 44:40Good.
  • 45:15That's right. So
  • 45:16we do know that they
  • 45:17are affected, actually,
  • 45:19because, you know, if it's,
  • 45:22if it's if if it's
  • 45:23Farheem,
  • 45:24you know,
  • 45:25once it breaks down, it
  • 45:27will be taken out in
  • 45:28in anemia.
  • 45:29But,
  • 45:31but that core is not
  • 45:33in the case of Fahraheem,
  • 45:34that core is not broken
  • 45:36for,
  • 45:37over four hundred hours.
  • 45:39So
  • 45:41as long as we're imaging
  • 45:42within the area,
  • 45:44the time that we have
  • 45:45validated our radio tracer,
  • 45:47we are safe.
  • 45:49What you can't assume and
  • 45:50and to be clear, what
  • 45:52you're injecting is picomolar.
  • 45:54So from a physiological point
  • 45:55of view, you're not gonna
  • 45:56see any effect. It's just
  • 45:57that your image after a
  • 45:59while will not represent,
  • 46:01the membrane potential or the,
  • 46:04or the monocyte trafficking. It's
  • 46:05just taken up,
  • 46:07wherever there's iron,
  • 46:08iron need. It's just over
  • 46:10two hundred and fifty hours
  • 46:11later. So you're that's where
  • 46:13we would worry about it,
  • 46:15but not in the not
  • 46:16within the imaging time.
  • 46:27Right. So we have there
  • 46:29what we have done. And
  • 46:30and for the member potential
  • 46:31compound, I think I showed
  • 46:32you some human studies. We
  • 46:33have an IND. We've done
  • 46:34first in human. We've done
  • 46:35over thirty of them now.
  • 46:36We have done
  • 46:38the test retest in multiple
  • 46:40patients on different days.
  • 46:42And that's the curve I
  • 46:44showed you, and I
  • 46:45thank you, Harriet, for pointing
  • 46:47this out. That's the curve
  • 46:48I showed you where I
  • 46:49said it's very constant.
  • 46:52This was surprising for us
  • 46:53because, you know, there is
  • 46:54big variability when we do
  • 46:55humans on different days.
  • 46:57It is just that this
  • 46:58is such a
  • 46:59tightly regulated,
  • 47:02physiological parameter that there was
  • 47:04very little change. So we've
  • 47:05we've tested that in but
  • 47:07I mean, it's indirectly, obviously,
  • 47:08but we've done that in
  • 47:09test retest. And even when
  • 47:10we did patients
  • 47:12well, for now, the chronic
  • 47:14is in pigs. When we
  • 47:15did pigs over time, I
  • 47:16showed you eight of those
  • 47:17that have gone for six
  • 47:18month,
  • 47:19the areas that were not,
  • 47:24when we did when we
  • 47:25first did the
  • 47:27the acute, the errors that
  • 47:28were not affected on multiple
  • 47:29times, that was the same.
  • 47:31So that was that was
  • 47:32reliable.
  • 47:33The obviously, when we did
  • 47:34the chronic, then the whole
  • 47:35the whole heart, then myocardium
  • 47:37was affected because this is
  • 47:38somatic IV injection.
  • 48:10Yes.
  • 48:17I would say yes. So
  • 48:19thank you. That's not good.
  • 48:20Another nice plug in. So
  • 48:22we have a Panama coming
  • 48:23in.
  • 48:26Let me I did mine.
  • 48:28We have a Panama coming
  • 48:30in
  • 48:31in
  • 48:33q three
  • 48:34twenty twenty six
  • 48:36on the so
  • 48:38I know it sounds long
  • 48:39from now, but I'm told,
  • 48:41you know, in the old
  • 48:41timelines, that's very fast.
  • 48:44I've been here eleven months,
  • 48:45so I've I've learned enough
  • 48:47now. It's
  • 48:48so this is a research
  • 48:50scanner
  • 48:51that we are working hard
  • 48:53on
  • 48:54making one day available
  • 48:56for clinical work.
  • 48:58The same way we have
  • 48:59a seven Tesla coming in.
  • 49:00We're there. We have now
  • 49:02the agreement that two days
  • 49:03a week will be available
  • 49:04for
  • 49:05clinical. I'm very keen on
  • 49:07on sharing these because
  • 49:10the seven Tesla would be
  • 49:11two days for clinical.
  • 49:13So I hope we'll be
  • 49:15able to do the same
  • 49:16on the Panama side
  • 49:18because I'm I'm putting my
  • 49:19money where my mouth is.
  • 49:20I mean, what's the point
  • 49:21of doing all this if
  • 49:22you can't see it? The
  • 49:23idea being that, you know,
  • 49:24if we do one day
  • 49:25a week and we see
  • 49:26a huge value, like you're
  • 49:27saying, well, then that would
  • 49:28justify that would give us
  • 49:29the argument for having more
  • 49:31of those installed clinically.
  • 49:33That's how we've done at
  • 49:34Pest General before. We we
  • 49:35started with a research one,
  • 49:36and then at one point,
  • 49:38surgeons refused to go in
  • 49:39unless they had the PET
  • 49:40and the MR. And it
  • 49:41was like, okay. Well, now
  • 49:42we're gonna have one clinical.
  • 49:43Can I ask the question?
  • 49:45Of course.
  • 49:47So a a question as
  • 49:48it relates to quantitative imaging
  • 49:50for clinical trials.
  • 49:51So I think as we're
  • 49:53getting better and better resolution,
  • 49:54especially with the sort of
  • 49:56PET MR, we're really stuck
  • 49:58as it relates to quantitative
  • 50:00imaging, especially as it relates
  • 50:01to even our new diagnostic
  • 50:02trials where we're we have
  • 50:04to use RECIST, which is
  • 50:05based just on
  • 50:07cross sectional imaging. Do you
  • 50:08have any thoughts on sort
  • 50:10of the evolution of that
  • 50:11field and where we should
  • 50:12be going?
  • 50:14Yes. I think resist is
  • 50:15a heresy in the age
  • 50:17of the diagnostics because
  • 50:19what you're measuring is
  • 50:21if you think ejection fraction
  • 50:24is too late compared to
  • 50:25membrane potential for the canary
  • 50:26in the mine,
  • 50:28This is you know, that
  • 50:29that tumor is not gonna
  • 50:31shrink for months before I
  • 50:32mean, this is not at
  • 50:33all useful.
  • 50:35What I showed in the
  • 50:36case of the,
  • 50:38NET and and prostate
  • 50:40is a full model, a
  • 50:41full dosimetry. We can do
  • 50:43that now.
  • 50:44The challenge is that currently,
  • 50:46if we were to do
  • 50:46this I mean, Larry would
  • 50:48love to do this every
  • 50:49day. But on his spec
  • 50:50scanning, it would take him
  • 50:51an hour and a half,
  • 50:52an hour to do that
  • 50:54full survey.
  • 50:56But there are scanners available
  • 50:57today that are
  • 50:59full ring spec systems where
  • 51:00you can do in ten
  • 51:01minutes what you do in
  • 51:02an hour and a half.
  • 51:04And,
  • 51:05we also are planning on
  • 51:06installing one, and we're hoping
  • 51:07that will be one also
  • 51:08on the clinical side. And
  • 51:10there, what you do is
  • 51:11just a simple survey,
  • 51:12a ten, twenty minute, but
  • 51:14every time.
  • 51:15And as you do that,
  • 51:16then you can see your
  • 51:17residency time of your tracer.
  • 51:19You can quantify your effective
  • 51:21dose, which is a lot
  • 51:22more I mean, that's what
  • 51:24people have been doing for
  • 51:25ages in in I one
  • 51:26thirty one when they needed
  • 51:27to quantify,
  • 51:29how much can you give
  • 51:30somebody who's coming back after
  • 51:32recurrence.
  • 51:32This is
  • 51:34there's nothing there. I wish
  • 51:35I could say, oh, this
  • 51:36is groundbreaking and very novel.
  • 51:38This is standard,
  • 51:40and we can do it
  • 51:40tomorrow if we had,
  • 51:43We just need a clinical
  • 51:44trial to catch up. Correct.
  • 51:45Oh, absolutely. So this is
  • 51:45available well well, you know,
  • 51:46well I mean, it's
  • 51:49there's
  • 51:50nothing
  • 51:51there that is
  • 51:55very novel. It is just
  • 51:57that for most trials, we
  • 51:58we just cut corners and
  • 51:59say, yeah. Let's look at
  • 52:00resist, but it's there. It's
  • 52:01available. And we can do
  • 52:02it. And in the past
  • 52:03center, we can do that
  • 52:04for any of those trials.
  • 52:06Question about AI, which you
  • 52:08talked a little bit about.
  • 52:10In lung cancer, for example,
  • 52:11there's a civil, which is
  • 52:13a way of using AI
  • 52:14to look at,
  • 52:16low dose screening, and and
  • 52:18sometimes it's more effective than
  • 52:20than, our current methods. So
  • 52:22and you talked a little
  • 52:23bit about, you know, standardizing
  • 52:25and the the inter
  • 52:27you know, different
  • 52:29Inter observer availability. Yes.
  • 52:33I think it's gonna go.
  • 52:34Is this something where AI
  • 52:36is gonna help
  • 52:37be more accurate, be more
  • 52:38better? Is it gonna actually
  • 52:41be able to replace some
  • 52:42of those radiologists
  • 52:44so that you can get
  • 52:45to,
  • 52:46you know, different places in
  • 52:47rural communities?
  • 52:48Where do you think AI
  • 52:49is is, is gonna
  • 52:52I was recently at a
  • 52:53talk in surgery. Don't ask
  • 52:54why, but it's surgery talk
  • 52:56for a surgeon who only
  • 52:58does surgery in the middle
  • 52:59of this the toxic and
  • 53:00here's my slide for AI
  • 53:01because you have to have
  • 53:02one. And I was like,
  • 53:04wow.
  • 53:04If surgery is now in,
  • 53:06then we're good.
  • 53:07I think it's not a
  • 53:08question of if. It's a
  • 53:09question of when. It's happening.
  • 53:11It is AI is taking
  • 53:12over a lot of what
  • 53:13we're doing.
  • 53:14The reason why you notice
  • 53:15I'm very careful in what
  • 53:16I'm showing
  • 53:18is because we are doing
  • 53:19a lot of deep learning,
  • 53:20and there are
  • 53:21what we call case of
  • 53:22hallucination where
  • 53:24every now and then you
  • 53:25get a case that doesn't
  • 53:26make any sense.
  • 53:28And our biggest worry is
  • 53:29that and this is why
  • 53:31I was very careful saying
  • 53:33this is an aid
  • 53:34as somebody's starting to use.
  • 53:37The big worry from many
  • 53:39of the ethicists right now
  • 53:40is that as the physician
  • 53:42relies more and more on
  • 53:43the on the tool, they
  • 53:45become more and more different
  • 53:47to the tool. And when
  • 53:48sometimes they feel like, oh,
  • 53:49I'm not sure, but, oh,
  • 53:50but think that I'm it
  • 53:52must be true. And and
  • 53:54you're still liable.
  • 53:55You're still responsible. So I
  • 53:57would have a word of
  • 53:58caution that,
  • 53:59yes, it is happening, but
  • 54:00I I don't see it
  • 54:03as the the panacea because
  • 54:06until we have such volumes
  • 54:08of data, which we don't
  • 54:09have today,
  • 54:10that any case we're gonna
  • 54:12see has been seen before.
  • 54:17I'm I'm sorry. I'm not
  • 54:18as enthusiastic as I was
  • 54:20about everything else I talked
  • 54:21about, but that's because we
  • 54:22do a lot of deep
  • 54:23learning in our we do
  • 54:24a lot of it, and
  • 54:26we see limitations.
  • 54:27So because of the limited
  • 54:28data we have, we don't
  • 54:30have
  • 54:31the data that Facebook has.
  • 54:32We don't have a billion
  • 54:34paths.
  • 54:35I mean, we don't have
  • 54:36a billion CTs, let alone
  • 54:37a billion paths.
  • 54:40We we probably need to
  • 54:41end if others have questions,
  • 54:43maybe come up afterwards, but
  • 54:44we're at time that