The use of radiotherapy (RT) in consolidating oligometastatic prostate cancer (OPCa) is a rapidly evolving treatment paradigm. Here we review our institutional experience using metastasis directed therapy (MDT) in the definitive management of men with OPCa.
OPCa treated with definitive RT were included. The Kaplan-Meier method and multivariable Cox regression analysis were performed to assess biochemical progression free survival (bPFS) and time to next intervention (TTNI). Cumulative incidence (CI) functions were used to calculate rates of local failure. Toxicity was assessed using CTCAE v4 criteria.
This study analyzed 156 OPCa patients and 354 metastatic lesions with median follow-up (fup) of 24.6 months. Of 150 patients with toxicity data, 53 (35%) experienced acute grade 1 toxicity, 8 (5%) had grade 2, and none had grade 3 toxicity. Only 13 (9%) had late toxicities. At 24 months the CI of local failure was 7.4%. Median bPFS for the entire cohort was 12.9 months and 52% at one year. On multivariable analysis, factors associated with prolonged bPFS were peri-RT androgen deprivation (ADT), lower GTV, and hormone sensitive (HS) OPCa. Median TTNI, including repeat RT, was 21.6 months. Median bPFS for men with HSPC was 17.2 months compared to 7.2 months in men with castrate-resistant OPCa (CROPCa) (p <0.0001) and cumulative incidence of local failure at 24 months was lower with HSOPCa (4.8% vs 12.1%; p=0.034). We analyzed 28 men with HSOPCa treated with a course of peri-RT ADT (median 4.3 months) with recovery of testosterone. At median 33.5 month fup, 20 have not developed bPFS, median bPFS has not yet been reached, and 24 month bPFS was 77%.
MDT can be effective across a wide ranges of OPCa subtypes, however with differential efficacy. Continued studies investigating the use of RT over the wide range of OPCa patients is warranted.
International journal of radiation oncology, biology, physics. 2019 Aug 13 [Epub ahead of print]
Matthew P Deek, Colburn Yu, Ryan Phillips, Daniel Y Song, Curtiland Deville, Stephen Greco, Theodore L DeWeese, Emmanuel S Antonarakis, Mark Markowski, Channing Paller, Samuel Denmeade, Michael Carducci, Patrick C Walsh, Kenneth J Pienta, Mario Eisenberger, Phuoc T Tran
Department of Radiation Oncology & Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA., Department of Radiation Oncology & Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Urology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA., Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA., Department of Urology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA., Department of Urology, Johns Hopkins University School of Medicine, Baltimore, MD, USA., Department of Radiation Oncology & Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Urology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA. Electronic address: .