2024
Using a Bayesian analytic approach to identify county-level ecological factors associated with survival among individuals with early-onset colorectal cancer
Siddique S, Baum L, Deziel N, Kelly J, Warren J, Ma X. Using a Bayesian analytic approach to identify county-level ecological factors associated with survival among individuals with early-onset colorectal cancer. PLOS ONE 2024, 19: e0311540. PMID: 39471191, PMCID: PMC11521299, DOI: 10.1371/journal.pone.0311540.Peer-Reviewed Original ResearchConceptsAge-of-onset colorectal cancerEarly-onset colorectal cancerEnd Results Program dataCenters for Disease Control and Prevention dataCounty-level factorsColorectal cancerHealth risk behaviorsIdentified principal componentsOdds of survivalPreventive servicesSurvival disparitiesLinear mixed modelsEOCRCChronic diseasesPreventive factorsUS countiesSalt Lake CountyCA residentsRisk behaviorsUnited StatesProgram dataCounty-levelOlder ageBayesian analytical approachYounger age
2021
Patterns of Care for Older Patients With Myelofibrosis: A Population-based Study
Meckstroth S, Wang R, Ma X, Podoltsev N. Patterns of Care for Older Patients With Myelofibrosis: A Population-based Study. Clinical Lymphoma Myeloma & Leukemia 2021, 21: e551-e558. PMID: 33648884, DOI: 10.1016/j.clml.2021.01.025.Peer-Reviewed Original ResearchConceptsPatterns of careOlder patientsEnd Results-Medicare databaseJAK inhibitor eraHigh-risk patientsPopulation-based studyUse of ruxolitinibJAK inhibitor ruxolitinibUnited States FoodRuxolitinib approvalMedian ageMedian timeTreatment patternsD claimsCurrent treatmentInhibitor ruxolitinibPatientsBetter outcomesClinical experienceDrug AdministrationMedicare Part BMyelofibrosisRuxolitinibStates FoodNew drugs
2019
Temporal patterns and predictors of receiving no active treatment among older patients with acute myeloid leukemia in the United States: A population‐level analysis
Zeidan AM, Podoltsev NA, Wang X, Bewersdorf JP, Shallis RM, Huntington SF, Gore SD, Davidoff AJ, Ma X, Wang R. Temporal patterns and predictors of receiving no active treatment among older patients with acute myeloid leukemia in the United States: A population‐level analysis. Cancer 2019, 125: 4241-4251. PMID: 31483484, PMCID: PMC7733320, DOI: 10.1002/cncr.32439.Peer-Reviewed Original ResearchMeSH KeywordsAgedFemaleHumansLeukemia, Myeloid, AcuteMaleRetrospective StudiesSEER ProgramUnited StatesConceptsAcute myeloid leukemiaTime of diagnosisOlder patientsActive treatmentMyeloid leukemiaMultivariable logistic regression modelMedian overall survivalPercentage of patientsLow-intensity therapyMajority of patientsNovel therapeutic optionsQuality of careLogistic regression modelsIntensity therapyTherapy receiptOverall survivalWorse survivalClinical factorsInferior survivalEntire cohortTherapeutic optionsPatient populationRetrospective analysisHigher oddsProvider characteristicsRBC transfusion independence among lower risk MDS patients receiving hypomethylating agents: a population-level analysis
Zeidan AM, Zhu W, Stahl M, Wang R, Huntington SF, Giri S, Podoltsev NA, Gore SD, Ma X, Davidoff AJ. RBC transfusion independence among lower risk MDS patients receiving hypomethylating agents: a population-level analysis. Leukemia & Lymphoma 2019, 60: 3181-3187. PMID: 31170846, DOI: 10.1080/10428194.2019.1622700.Peer-Reviewed Original ResearchConceptsRBC transfusion independenceLR-MDS patientsTransfusion independenceHMA initiationRBC transfusionClinical effectivenessReal-life clinical effectivenessRed blood cell transfusionLower-risk myelodysplastic syndromesLow-risk MDS patientsRisk MDS patientsBlood cell transfusionRisk myelodysplastic syndromesHMA therapyLR-MDSCell transfusionMost patientsDisease courseMDS patientsMedicare databaseMyelodysplastic syndromePopulation-level estimatesLower oddsTransfusionPatientsImpact of Hydroxyurea on Survival and Risk of Thrombosis Among Older Patients With Essential Thrombocythemia.
Podoltsev NA, Zhu M, Zeidan AM, Wang R, Wang X, Davidoff AJ, Huntington SF, Giri S, Gore SD, Ma X. Impact of Hydroxyurea on Survival and Risk of Thrombosis Among Older Patients With Essential Thrombocythemia. Journal Of The National Comprehensive Cancer Network 2019, 17: 211-219. PMID: 30865915, DOI: 10.6004/jnccn.2018.7095.Peer-Reviewed Original ResearchConceptsImpact of hydroxyureaThrombotic eventsEssential thrombocythemiaEffect of hydroxyureaOlder patientsOverall survivalLower riskMultivariable Cox proportional hazards regression modelsCox proportional hazards regression modelHigh-risk essential thrombocythemiaProportional hazards regression modelsRetrospective cohort studyRisk of deathSEER-Medicare databaseHazards regression modelsRisk of thrombosisHU usersFrontline therapyCohort studyCurrent guidelinesStudy populationPatientsReal-world settingThrombosisOlder adults
2018
Oncologist volume and outcomes in older adults diagnosed with diffuse large B cell lymphoma
Huntington SF, Hoag JR, Zhu W, Wang R, Zeidan AM, Giri S, Podoltsev NA, Gore SD, Ma X, Gross CP, Davidoff AJ. Oncologist volume and outcomes in older adults diagnosed with diffuse large B cell lymphoma. Cancer 2018, 124: 4211-4220. PMID: 30216436, PMCID: PMC6263848, DOI: 10.1002/cncr.31688.Peer-Reviewed Original ResearchConceptsDiffuse large B-cell lymphomaLarge B-cell lymphomaB-cell lymphomaOlder adultsCell lymphomaPopulation-based cohort analysisHigh-quality cancer careAnthracycline-containing regimenGuideline-adherent therapyHigh-volume providersNumber of patientsLook-back periodCytotoxic regimensSystemic therapyImproved survivalClinical outcomesReduced hospitalizationsLymphoma patientsCancer careCohort analysisMedicare beneficiariesComplex surgeryDLBCL casesLymphomaClinical volumeRegional Practice Patterns and Racial/Ethnic Differences in Intensity of End‐of‐Life Care
Wang S, Hsu SH, Huang S, Doan KC, Gross CP, Ma X. Regional Practice Patterns and Racial/Ethnic Differences in Intensity of End‐of‐Life Care. Health Services Research 2018, 53: 4291-4309. PMID: 29951996, PMCID: PMC6232508, DOI: 10.1111/1475-6773.12998.Peer-Reviewed Original ResearchConceptsIntensity of endHospital referral regionsRegional practice patternsPractice patternsLife careEthnic differencesLife care expendituresLocal practice patternsCancer decedentsMedicare databaseRacial/Ethnic DifferencesReferral regionsCare expendituresCareEnd resultDifferencesEpidemiologyDecedentsPhysician peer group characteristics and timeliness of breast cancer surgery
Bachand J, Soulos PR, Herrin J, Pollack CE, Xu X, Ma X, Gross CP. Physician peer group characteristics and timeliness of breast cancer surgery. Breast Cancer Research And Treatment 2018, 170: 657-665. PMID: 29693229, PMCID: PMC6048589, DOI: 10.1007/s10549-018-4789-8.Peer-Reviewed Original ResearchConceptsPhysician peer groupsSurgical delayProvider densityPatient racial compositionBreast cancerEnd Results-Medicare dataBreast cancer patientsBreast cancer surgeryResultsThe study sampleConclusionsThe likelihoodBlack patientsCancer surgeryCancer patientsSurgeryPatientsStudy sampleWomenCancerAssociationGroupGroup characteristicsPurposeLittleInterdisciplinary groupPeer groupEpidemiology
2017
Hypomethylating agent therapy use and survival in older patients with chronic myelomonocytic leukemia in the United States: A large population‐based study
Zeidan AM, Hu X, Long JB, Wang R, Ma X, Podoltsev NA, Huntington SF, Gore SD, Davidoff AJ. Hypomethylating agent therapy use and survival in older patients with chronic myelomonocytic leukemia in the United States: A large population‐based study. Cancer 2017, 123: 3754-3762. PMID: 28621841, PMCID: PMC6540984, DOI: 10.1002/cncr.30814.Peer-Reviewed Original ResearchConceptsChronic myelomonocytic leukemiaRisk of deathSupportive careEnd Results-Medicare databaseOlder adultsMedian OS timeOverall survival benefitCohort of patientsProportional hazards modelUse of HMAsMedian OSAgent therapySurvival benefitOS timeCMML patientsMyelomonocytic leukemiaHazards modelHMA treatmentPatientsTemporal improvementSecondary analysisPropensity scoreLimited evidenceSurvival changesApproval
2016
Modest improvement in survival of patients with refractory anemia with excess blasts in the hypomethylating agents era in the United States
Zeidan AM, Wang R, Gross CP, Gore SD, Huntington SF, Prebet T, Abel GA, Davidoff AJ, Ma X. Modest improvement in survival of patients with refractory anemia with excess blasts in the hypomethylating agents era in the United States. Leukemia & Lymphoma 2016, 58: 982-985. PMID: 27558206, DOI: 10.1080/10428194.2016.1214954.Peer-Reviewed Original ResearchDisease‐related costs of care and survival among Medicare‐enrolled patients with myelodysplastic syndromes
Zeidan AM, Wang R, Davidoff AJ, Ma S, Zhao Y, Gore SD, Gross CP, Ma X. Disease‐related costs of care and survival among Medicare‐enrolled patients with myelodysplastic syndromes. Cancer 2016, 122: 1598-1607. PMID: 26970288, PMCID: PMC5509410, DOI: 10.1002/cncr.29945.Peer-Reviewed Original ResearchConceptsMyelodysplastic syndromeEligible patientsHazard ratioMedicare beneficiariesMultivariate Cox proportional hazards modelEnd Results-Medicare databasePropensity score-matched groupsCox proportional hazards modelOverall study populationSubgroup of patientsConfidence intervalsCost-saving interventionEnd of studyProportional hazards modelElderly patientsOverall survivalDisease characteristicsMDS cohortPatient outcomesStudy populationInternational ClassificationWarrants additional researchHazards modelPatientsSurvival rate
2015
The Role of Patient Factors, Cancer Characteristics, and Treatment Patterns in the Cost of Care for Medicare Beneficiaries with Breast Cancer
Xu X, Herrin J, Soulos PR, Saraf A, Roberts KB, Killelea BK, Wang SY, Long JB, Wang R, Ma X, Gross CP. The Role of Patient Factors, Cancer Characteristics, and Treatment Patterns in the Cost of Care for Medicare Beneficiaries with Breast Cancer. Health Services Research 2015, 51: 167-186. PMID: 26119176, PMCID: PMC4722219, DOI: 10.1111/1475-6773.12328.Peer-Reviewed Original ResearchConceptsBreast cancer careHospital referral regionsCancer careMedicare expendituresBreast cancerRadiation therapyTreatment factorsMean Medicare expendituresEnd Results-MedicareSpecific treatment modalitiesContribution of patientCost of careHighest spending quintilePatient factorsTreatment patternsTumor characteristicsCancer characteristicsTreatment modalitiesReferral regionsMedicare beneficiariesQuintilePatientsCancerCareTherapyOlder Women With Localized Breast Cancer: Costs And Survival Rates Increased Across Two Time Periods
Feinstein AJ, Long J, Soulos PR, Ma X, Herrin J, Frick KD, Chagpar AB, Krumholz HM, Yu JB, Ross JS, Gross CP. Older Women With Localized Breast Cancer: Costs And Survival Rates Increased Across Two Time Periods. Health Affairs 2015, 34: 592-600. PMID: 25847641, DOI: 10.1377/hlthaff.2014.1119.Peer-Reviewed Original ResearchConceptsStage II diseaseStage III diseaseCancer-related costsCancer careBreast cancerMedian costSurvival rateEnd Results Program-MedicareFive-year survivalCancer care costsBreast surgerySurvival outcomesImproved outcomesOlder womenRadiation therapyCare costsStage IIDiseaseStudy periodWomenCancerCareSignificant national attentionOutcomesPercent
2014
Understanding Regional Variation in Medicare Expenditures for Initial Episodes of Prostate Cancer Care
Wang SY, Wang R, Yu JB, Ma X, Xu X, Kim SP, Soulos PR, Saraf A, Gross CP. Understanding Regional Variation in Medicare Expenditures for Initial Episodes of Prostate Cancer Care. Medical Care 2014, 52: 680-687. PMID: 25023913, PMCID: PMC4129645, DOI: 10.1097/mlr.0000000000000158.Peer-Reviewed Original ResearchConceptsAncillary proceduresPatient characteristicsTreatment modalitiesTreatment intensityEnd Results-Medicare databaseProstate cancer careSpecific treatment modalitiesContribution of patientHospital referral regionsInitial treatmentCancer careInitial episodeNoncancer controlsProstate cancerQuintile 5Referral regionsSubstantial geographic variationCare costsMedicare expendituresCostly modalityTreatment factorsMean expenditureLowest expenditure quintileSurgeryModalitiesEvolution of Breast Cancer Screening in the Medicare Population: Clinical and Economic Implications
Killelea BK, Long JB, Chagpar AB, Ma X, Wang R, Ross JS, Gross CP. Evolution of Breast Cancer Screening in the Medicare Population: Clinical and Economic Implications. Journal Of The National Cancer Institute 2014, 106: dju159. PMID: 25031307, PMCID: PMC4155428, DOI: 10.1093/jnci/dju159.Peer-Reviewed Original ResearchConceptsEnd Results-MedicareBreast cancer stageCohort of womenEarly-stage tumorsBreast cancer screeningAdjunct imagingSignificant changesCancer screeningCancer stageIncidence rateBreast cancerAdjunct procedureOlder womenMedicare populationMedicare beneficiariesClinical practiceComputer-aided detectionPoisson regressionNational feeCohortBreast ultrasoundWomenEarlier cohortsLater cohortsMedicare spending
2013
The cost implications of prostate cancer screening in the Medicare population
Ma X, Wang R, Long JB, Ross JS, Soulos PR, Yu JB, Makarov DV, Gold HT, Gross CP. The cost implications of prostate cancer screening in the Medicare population. Cancer 2013, 120: 96-102. PMID: 24122801, PMCID: PMC3867600, DOI: 10.1002/cncr.28373.Peer-Reviewed Original ResearchConceptsProstate cancerScreening costsAnnual screening costsPopulation-based cohortProstate cancer screeningHospital referral region levelMale Medicare beneficiariesProstate-specific antigenCancer screeningLowest quartileHRR levelMedicare populationMedicare beneficiariesOlder menNational feeCancerService Medicare programCancer diagnosisMenQuartilePSACost implicationsAnnual expenditureMedicare programBiopsyTrends and clinical implications of preoperative breast MRI in Medicare beneficiaries with breast cancer
Killelea BK, Long JB, Chagpar AB, Ma X, Soulos PR, Ross JS, Gross CP. Trends and clinical implications of preoperative breast MRI in Medicare beneficiaries with breast cancer. Breast Cancer Research And Treatment 2013, 141: 155-163. PMID: 23942872, PMCID: PMC3893026, DOI: 10.1007/s10549-013-2656-1.Peer-Reviewed Original ResearchConceptsPreoperative breast magnetic resonance imagingBreast magnetic resonance imagingBreast-conserving surgeryMagnetic resonance imagingBreast cancerSurgical approachBilateral cancerMRI useOlder womenAssociation of MRIEnd Results-Medicare databasePreoperative MRI useContralateral prophylactic mastectomyType of surgeryCohort of womenBilateral mastectomyUnilateral mastectomyProphylactic mastectomyMastectomyMedicare beneficiariesSurgeryResonance imagingClinical implicationsCancerInvasive surgery
2012
The impact of hypomethylating agents on the cost of care and survival of elderly patients with myelodysplastic syndromes
Wang R, Gross CP, Frick K, Xu X, Long J, Raza A, Galili N, Zikria J, Guan Y, Ma X. The impact of hypomethylating agents on the cost of care and survival of elderly patients with myelodysplastic syndromes. Leukemia Research 2012, 36: 1370-1375. PMID: 22917770, PMCID: PMC3458648, DOI: 10.1016/j.leukres.2012.07.020.Peer-Reviewed Original ResearchConceptsCost of careMyelodysplastic syndromeMDS patientsMedicare expendituresComparative cost-effectiveness studyCohort of patientsTwo-year survivalNon-cancer controlsCost-effectiveness studiesElderly patientsPrevalent cancerEconomic burdenPatientsMajor subtypesSurvivalCareSyndromeUnited StatesHMAsSurvival probabilityEarly periodCohortAgentsCancerSubtypes
2009
Clarification on the categorization of comorbidities
Wang R, Ma X. Clarification on the categorization of comorbidities. Leukemia Research 2009, 34: e74. PMID: 19783302, PMCID: PMC2815216, DOI: 10.1016/j.leukres.2009.08.036.Peer-Reviewed Original Research
2008
Jakking up tumor registry reporting of the myeloproliferative neoplasms
Selinger HA, Ma X. Jakking up tumor registry reporting of the myeloproliferative neoplasms. American Journal Of Hematology 2008, 84: 124-126. PMID: 19117021, DOI: 10.1002/ajh.21333.Peer-Reviewed Original Research