Metabolic syndrome predicts for shorter response to hormonal therapy in prostate cancer

Abstract

4554 Background: Metabolic syndrome (MS) includes obesity, insulin resistance, dyslipidemia and hypertension. Recent studies have linked the individual components of MS to an increased risk for prostate cancer (PC) and worse PC outcomes. Methods: A retrospective chart review was performed on 100 consecutive patients treated for prostate cancer at a Veteran’s Administration oncology clinic between 1998–2005. MS was diagnosed according to Adult Treatment Panel III criteria, and was present with ≥3 of 5 components: hypertension (SBP ≥140 mmHg and/or DBP ≥90 mmHg on 2 outpatient visits; obesity (BMI ≥30); hypertriglyceridemia (>150 mg/dL on 2 fasting laboratories); LDL 110 mg/dL (2 outpatient am values while not on steroids). PC variables included baseline PSA at time of PC diagnosis, PSA at initiation of hormonal therapy (HT), presence of documented metastasis at time of HT, and primary PC treatment. We examined time to PSA progression (TTP) and median overall survival (OS) for PC among patients with and without MS using Kaplan-Meier curves and Cox proportional hazard models. Results: 83 patients treated with HT for PC were identified, and 41 (49%) met criteria for MS. Median age in both groups was 68. Median TTP was 16 months with MS vs. 46 months without MS (p = 0.001). In those patients with documented metastasis (DM) at time of HT, median TTP was 11 months with MS vs. 32 months without MS (p = 0.006). OS from time of HT was 40 months with MS, and median survival time for no MS was not reached. In multivariate regression analyses, the hazard ratio (HR) for increased TTP with MS was 3.49 (95% CI 1.86–6.54). HR for TTP with documented metastasis was 5.3 (95% CI 2.65–12.8). Conclusions: This retrospective analysis suggests patients with MS treated with HT for PC have significantly shorter time to PSA progression and worse overall survival. This analysis supports the need for a prospective evaluation of MS as a risk factor for early development of HRPC. [Table: see text] No significant financial relationships to disclose.