e578 Background: Emerging evidence has suggested that local tumor control may enhance the effect of subsequent therapies in patients with metastatic prostate cancer. However, little is known about surgical safety of cytoreductive prostatectomy (CRP). In this study, we report the first interim analysis of a phase I study evaluating the safety and feasibility of CRP. Methods: The study was approved by the IRB and activated in June, 2015. Individuals with newly diagnosed clinical metastatic prostate cancer to lymph node or bones (cT1-3N1M0 or cT1-3N0M1a-b) were recruited. Following surgery, all patients received androgen deprivation therapy. The primary endpoint is the major complication rate (Clavien ≥ III). The secondary outcome measures are the time to PSA nadir and rate of incontinence (pad-free). Results: A total of 20 men from two institutions have been enrolled and undergone CRP. Overall, 6 (35.3%) perioperative complications were observed, including 1 major complication (Clavien ≥ III). There were 5 minor complications, including deep venous thrombus (Clavien II), postoperative ileus (Clavien II), and 3 cases of urethral anastomotic leaks (Clavien I). In men with a minimum of 6 month follow-up, PSA < 0.2 ng/ml in 63.6% of men and 50% of men were pad free. Conclusions: CRP is surgically feasible in carefully selected patients. However, early incontinence rate is high. Further studies are warranted to further define long-term complications and verify the oncologic benefits of the surgery. Clinical trial information: NCT02458716. [Table: see text]
MP52-09 MULTICENTRIC PROSPECTIVE LOCAL TREATMENT OF METASTATIC PROSTATE CANCER (LOMP) TRIAL: INTERIM ANALYSIS OF CLINICAL OUTCOMES AND PROGNOSTIC FACTORS
