Preoperative Serum Sex Hormone-Binding Globulin as a Predictive Marker for Extraprostatic Extension of Tumor in Patients with Clinically Localized Prostate Cancer

Abstract

OBJECTIVES: We investigated the relationships of serum sex hormone-binding globulin (SHBG) level with known prognostic factors for prostate cancer in men who received radical retropubic prostatectomy (RRP) for clinically localized prostate cancer. METHODS: Preoperative serum levels of SHBG were analyzed in 288 consecutive patients who were scheduled to undergo RRP for clinically localized prostate cancer. We investigated the potential associations of preoperative serum SHBG level with various clinical and pathological factors. Accuracy of variables in predicting adverse pathological features was assessed via receiver operator characteristics (ROC) curves. RESULTS: In univariate analysis, preoperative serum SHBG level was observed to be significantly associated with extraprostatic extension of a tumor (p=0.019) and with pathological Gleason score (p=0.001). In multivariate analysis, serum SHBG level (p=0.039) along with serum PSA (p<0.001) level, biopsy Gleason score (p<0.001), and clinical stage (p=0.004) was observed to be an independent predictor of the extraprostatic extension of prostate cancer. The area under ROC curve that demonstrated the performance of a multivariate logistic regression model (MLRM), which included serum SHBG level and other preoperative variables, in predicting extraprostatic extension of tumor was larger than that of MLRM without SHBG (0.797 vs. 0.758, p=0.121). Meanwhile, serum SHBG level was not observed to be significantly associated with pathological Gleason score in multivariate analysis (p=0.303). CONCLUSIONS: Our data showed that serum SHBG level is an independent predictive factor for extraprostatic extension of tumor in patients with clinically localized prostate cancer.