Real‐world evidence of outcomes of oligometastatic hormone‐sensitive prostate cancer patients treated with metastasis‐directed therapy

Abstract

AbstractObjectiveTo investigate characteristics and outcomes of oligometastatic hormone‐sensitive prostate cancer (mHSPC) patients undergoing metastases‐directed therapy (MDT) with external beam radiation therapy (EBRT).Materials and MethodsWe relied on an institutional tertiary‐care database to identify mHSPC patients who underwent EBRT as MDT between 12/2019 and 12/2022. Main outcomes consisted of progression to metastatic castration‐resistant prostate cancer (mCRPC) and overall mortality (OM). Oligometastatic was defined as ≤3 metastases and bone and/or lymph node deposits were treated with conventional doses up to 54 Gy or with hypofractionated stereotactic regimes of median 24 Gy (20–27 Gy).ResultsOverall, 37 patients treated with EBRT as MDT were identified. The median follow‐up was 13 months. Median age at MDT was 71 years and 84% exhibited ECOG performance status 0. The median baseline PSA at diagnosis was 10 ng/mL. Overall, primary local therapy consisted of radical prostatectomy (65%), followed by external beam radiation therapy to the prostate (11%), focal therapy (8%), and palliative transurethral resection of the prostate (5%). Overall, 32% exhibited de novo oligometastatic mHSPC. Bone metastases were present in 78% versus 19% lymph node metastases versus 3% both. The distribution of targeted oligo‐metastases was 62% versus 38% for respectively one metastasis versus more than one metastasis. Androgen deprivation therapy (ADT) was combined with MDT in 84%. Moreover, 19% received combination therapy with apalutamide/enzalutamide and 12% with abiraterone or docetaxel. The median time to mCRPC was 50 months. In incidence analyses, 13% developed mCRPC after 24 months. OM after 24 months was 15% in mHSPC patients receiving MDT. Significant OM differences were observed after stratification into targeted metastatic burden (<0.05). No high‐grade adverse events were recorded during MDT.ConclusionOur real‐world data suggest that MDT represents a safe treatment option for well‐selected oligometastatic mHSPC patients.