The role of cytoreductive radical prostatectomy in the management of patients with metastatic hormone-sensitive prostate cancer.

157 Background: Cytoreductive radical prostatectomy (cRP) has emerged as an alternative treatment option to radiation therapy in men with low risk metastatic hormone sensitive prostate cancer (mHSPC). It was the purpose of our analysis to evaluate if different combinations of androgen deprivation therapy have an impact on pathohistological findings and oncological outcome in men undergoing cRP. Methods: We performed a retrospective analysis of 104 patients who underwent cRP and pelvic lymph node dissection for low volume mHSPC. Prior to cRP, all patients underwent at least 6 months of neoadjuvant systemic therapy with ADT (n=15, 14.4%), ADT + Abi (n=26, 25%), ADT+Apalutamide (n=37, 35.6%), ADT+enzalutamide (n=10, 9.6%), ADT+docetaxel (n=18, 17.3%). We analyzed pathohistology of the cRP and lymphadenectomy specimens and we assessed cancer specific survival (CSS), progression-free survival (PFS), metastatic PFS and overall survival (OS). In addition, surgery related complications and continence were assessed. Results: Mean age was 63 (45-76) years. Median follow-up was 62.1 (2-186) months. Median initial PSA and median PSA at time of surgery was 110 (25-465) ng/ml and 1.25 (<0.01-5.6) ng/ml, resp. Pathohistology of the total group revealed pT0 in 5 (4.8%) pts and pT2a-c, pT3a/b in 16(15.4%) and 83 (79.8%), resp. Pathohistology depending on the type of ADT is given in table 1. pN+ was observed in 45 (43.2%) patients with 1-19 positive lymph nodes and positive surgical margins were identified in 36 (34.6%). Local recurrence was observed in 2 (1.9%) pts. We observed Clavien-Dindo grade III-IV complications in 16 (15.4%) patients. With regard to continence, no, mild (1-2 pads/day) or severe incontinence was observed in 67.7%, 18.2%, and 14.1%, resp. Median OS was 84 months, median clinical progression free survival was 72 months. Conclusions: Based on our data, 75% of patients demonstrate viable and significant prostate cancer despite optimal PSA response to combined neoadjuvant ADT making this a strong argument for local surgical treatment in well selected patients with mHSPC. ADT/apalutamide and ADT/docetaxel are associated with the lowest risk of lymph node metastases making this the preferrable combination. Analysis of CSS, OS and PFS are under way to assess if those findings translate into superior oncological outcome. Surgery related side effects are low if cRP is performed in experienced hands. cRP should be discussed as one option of local treatment in multidisciplinary tumor boards. Pathology dependent on type of ADT. n pT0n (%) pT2a/bn (%) pT2cn (%) pT3a/bn (%) pN+n (%) R1n (%) ADT 15 1 (0.7) 0 2 (13.3) 12 (75) 9 (60) 5 (33.3) ADT + Abi/Pred 26 1 (0.4) 1 (0.4) 3 (11.5) 21 (80.8) 13 (50) 11 (42.3) ADT + Apalutamide 37 2 (0.5) 2 (0.5) 5 (13.5) 27 (73) 7 (19) 7 (19) ADT + enzalutamide 8 0 1 (0.12) 0 7 (87) 6 (75) 3 (37.5) ADT + docetaxel 18 1 (0.5) 1 (0.5) 1 (0.5) 15 (83.3) 7 (38.9) 9 (50)