Radical prostatectomy as a component of multimodal therapy for highly selected M1 prostate cancer patients.

Abstract

251 Background: Men who present with limited metastasis at the time of prostate cancer (PCa) diagnosis are typically managed with systemic therapy alone and the primary site of disease is not addressed. Systemic therapy with recently approved agents has been shown to improve survival in men with metastatic PCa; however the role of local therapy remains untested. Here, we examine the role of definitive surgical treatment of the primary tumor in a multimodal approach to highly selected patients with oligometastatic disease to maximize local and systemic cancer control. Methods: 20 patients with limited metastatic burden underwent RP as a component of multimodal therapy. Baseline characteristics, details of management, surgical outcomes, and disease progression defined as initiation of chemotherapy, new metastasis, or reinitiation of ADT were characterized. Results: Median age at RP was 61 years. Metastatic burden was assessed with whole body imaging; 17 of 20 patients had bone metastases (mets) (median 1, IQR 1,3) and 7 of 20 patients had retroperitoneal node mets. No patients had visceral mets. All patients had RP and pelvic lymph node dissection; 4 patients also had retroperitoneal lymph node dissection. There was one grade III surgical complication. 75% of patients reported continence within 12 months of RP. Patients received RT to bone (n=10), bone and pelvis (n=4), or no RT (n=6). Median neoadjuvant ADT was 4 months (IQR 3, 5) for all patients and neoadjuvant + adjuvant ADT was 9 months (IQR 6, 10) in 11 patients who discontinued ADT. At median follow-up of 19 months (IQR 10, 33) since RP, 12-month PFS was 65% (95%CI 35, 84). Among the 11 patients who discontinued ADT, 5 were non-castrate and had no evidence of disease progression. 4 patients had continuous ADT due to disease progression. There were no local recurrences after surgery. Conclusions: Multimodal therapy that includes RP is feasible and well-tolerated with acceptable low rate of surgical complications and good return of urinary continence. ADT was discontinued in a limited number of patients without signs of disease progression at short-term follow-up. Further evaluation of this therapeutic strategy should be considered in a prospective clinical trial.