You have accessJournal of UrologyProstate Cancer: Advanced (including Drug Therapy) I (PD10)1 Apr 2020PD10-04 IMPACT OF PRIMARY PROSTATE CANCER TREATMENT WITH SUBSEQUENT METASTATIC DISEASE: COMPARATIVE ANALYSIS AND SURVIVAL OUTCOMES IN A REAL-WORLD PRACTICE SETTING Mohammed Shahait, Daniel Lee*, Hamzeh Alshannaq, Ryan Dobbs, Jessica Kim, Tuanyuan Guan, Vivek Narayan, and David Lee Mohammed ShahaitMohammed Shahait More articles by this author , Daniel Lee*Daniel Lee* More articles by this author , Hamzeh AlshannaqHamzeh Alshannaq More articles by this author , Ryan DobbsRyan Dobbs More articles by this author , Jessica KimJessica Kim More articles by this author , Tuanyuan GuanTuanyuan Guan More articles by this author , Vivek NarayanVivek Narayan More articles by this author , and David LeeDavid Lee More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000844.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Treatment options for clinically localized prostate cancer have included either radical prostatectomy (RP) or several different modalities of radiation therapy. There is conflicting evidence about the relative impact of the primary treatment on the time to develop castrate-resistant prostate cancer, although recent small studies have suggested a possible benefit for those undergoing RP compared to radiation therapy. The objective of this study is to compare the impact of previous local treatment modalities on progression to castrate-resistant state, and overall survival in men with newly diagnosed metastatic prostate cancer via utilization of real-world registry data. METHODS: We conducted a retrospective analysis using the Flatiron Health electronic health record-derived database, a nationwide database comprised of de-identified patient-level structured and unstructured data, curated via technology-enabled abstraction between 2010 and 2018. Eligible patients had received previous radiation therapy or surgery for their local disease and had progressed into metastatic disease. We used the date of metastasis diagnosis as the index date. Kaplan-Meier estimates were used to measure overall survival. Cox proportional hazards regression models were used to test the association between prior local treatment and progression to castrate-resistant state, as well as, overall survival; models were adjusted for age ,race, Prostate specific antigen (PSA), Gleason score, Castrate-resistant state, administration of androgen deprivation before metastasis, and treatment year. RESULTS: Of 664 identified patients meeting the inclusion criteria, 310 (47%) initially underwent radical prostatectomy with or without adjuvant radiation and 354 (53%) received radiation alone. Median follow up from the date of metastasis for RP group, and radiation group was 30 months (17.5,42.4), and 29.4 months (18.6,45.4), respectively. Unadjusted cause-specific hazard regression showed that patients who received radiation therapy had 45% higher risk of developing castrate-resistant state compared to RP group [HR:1.45, CI:1.2-1.74, P<0.001]. This association remained significant upon adjusting for patient and disease-specific parameters [HR: 1.326, CI: 1.035-1.7, P= 0.0259] On multivariable analysis, after developing metastatic disease men who received radiation alone had 77% higher overall mortality [HR:1.77, CI:1.25-2.5, P= 0.0013] compared to men who underwent RP. CONCLUSIONS: Among patients with metastatic prostate cancer treated in routine clinical practice, those who had undergone prior RP had a lower risk of developing castrate-resistant state and improved overall survival from the date of metastasis compared to patients with metastatic disease who had received prior local radiation therapy. Notwithstanding the inherent selection bias at the time of choosing the type of local treatment because of unmeasured confounding variables, the results from this study add to the growing evidence that support the benefit of extirpation of the primary disease might confer improved overall survival after developing metastatic disease. Source of Funding: none © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e245-e245 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Mohammed Shahait More articles by this author Daniel Lee* More articles by this author Hamzeh Alshannaq More articles by this author Ryan Dobbs More articles by this author Jessica Kim More articles by this author Tuanyuan Guan More articles by this author Vivek Narayan More articles by this author David Lee More articles by this author Expand All Advertisement PDF downloadLoading ...