(P055) Can High-Grade Prostate Cancer (Gleason 8–10) Be Cured With Definitive Local Therapy Without Testosterone Suppression? Five-Year Outcomes Employing Up-Front Prostatectomy in Patients With Clinically Localized, Nonmetastatic Disease

Darrion L. Mitchell, MD, PhD, Kyle Russo, MD, Mark C. Smith, MD, Sarah L. Mott, MS, John M. Watkins, MD; Department of Radiation Oncology, Holden Comprehensive Cancer Center, University of Iowa; Bismarck Cancer Center

PURPOSE: High-grade prostate cancer (HGPC) is associated with an aggressive clinical course and poor outcomes; thus, a common approach involves the combination of long-term testosterone suppression with definitive local therapy. Small single-institution case series report that long-term disease control can be obtained in selected patients who undergo definitive local therapy alone; however, prognostic factors for this approach remain to be identified. The current investigation seeks to describe disease control and survival outcomes for patients with clinically localized HGPC at biopsy who were managed with primary radical prostatectomy (RP) without systemic therapy, with analyses performed to identify prognostic factors associated with disease control. 

MATERIALS AND METHODS: Patients were retrospectively identified for inclusion by biopsy-proven Gleason 8–10 adenocarcinoma managed with primary RP, without preoperative evidence of nodal or distant metastasis. Patient who received any preoperative intervention or adjuvant hormone therapy were excluded, as were patients with insufficient prostate-specific antigen (PSA) follow-up (< 12 mo). Patient-, tumor-, and treatment-related factors were analyzed for association with freedom from failure (FFF, defined as PSA > 0.2 ng/mL and rising or upon initiation of salvage therapy), employing Cox proportional hazards regression. The Kaplan-Meier method was employed for estimation of FFF and survival. 

RESULTS: From 2003–2010, a total of 69 eligible patients were identified. Median age was 63 years (range: 48–75 yr) and median PSA was 11.7 ng/mL (range: 3.5–64.9 ng/mL). Gleason score (GS) at RP was < 7, 8, and > 9 for 22, 17, and 29 patients, respectively. Extraprostatic extension, involved surgical margin, seminal vesicle invasion, and lymph node involvement were identified in 32, 33, 18, and 6 patients, respectively, with adjuvant radiotherapy delivered to 5 patients. At a median follow-up of 67.3 months (range: 13.3–141.2 mo), 40 patients had disease recurrence, and 8 patients died (6 cancer-specific). The 5-year FFF and overall survival (OS) rates were 39% (95% confidence interval [CI], 21%–58%) and 87% (95% CI, 72%–94%), respectively. Primary and overall Gleason score at RP, involved surgical margin, seminal vesicle involvement, nodal involvement, and elevated initial postprostatectomy PSA were significantly associated with FFF in the univariate analysis, with primary GS at RP (hazard ratio [HR] = 1.80; P < .01) and post-RP PSA (HR = 4.64; P < .01) significant in the multivariate analysis.

CONCLUSIONS: Patients with HGPC at diagnosis have high rates of early disease recurrence, though mortality at 5 years remains low. Following RP without systemic therapy, high primary GS and initial post-RP PSA were independently associated with worse FFF outcomes.

Proceedings of the 97th Annual Meeting of the American Radium Society- americanradiumsociety.org