HYPOGONADISM IS AN INDEPENDENT PREDICTOR OF NODAL METASTASES IN PROSTATE CANCER PATIENTS UNDERGOING EXTENDED PELVIC LYMPH NODE DISSECTION Eugenio Ventimiglia1, Paolo Capogrosso1, Michele Colicchia1, Luca Boeri1, Alessandro Serino1, Giulia Castagna1, Fabio Castiglione1, Giovanni La Croce1, Lorenzo Rocchini1, Andrea Gallina1, Nazareno Suardi1, Alberto Briganti1,2, Rocco Damiano2, Montorsi Francesco1, Andrea Salonia1,2 1Dept. of Urology, University Vita-Salute San Raffaele, Milan, Italy Doctorate Program in Urology, Magna Graecia University Catanzaro, Italy 2Research OBJECTIVES - To assess the association between preoperative hypogonadism (defined as total testosterone (tT) <3 ng/ml) with lymph node invasion (LNI) in patients treated with radical prostatectomy (RP) and extended pelvic lymph node dissection (ePLND) for clinically localized prostate cancer (PCa). METHODS - Preoperative serum tT was measured in a cohort of 1009 consecutive Caucasian-European patients (mean age 64.8 years, range 41-84) submitted to RP with ePLND. None of the patients had taken any hormonal neoadjuvant treatment or other hormonal preparations during the previous 12 mo. Serum tT was measured the day before surgery (8–10 AM) in all cases. Logistic regression models tested the associations among predictors (eg, prostate specific antigen [PSA], clinical stage, biopsy Gleason score, and tT) and LNI. RESULTS - Median tT was 4.5 ng/ml [mean: 4.5; range: 0.02–13.6]. Hypogonadism was observed in 113 (11.2%) patients. LNI was found in 113 (11.2%) patients, with a mean number of lymph nodes removed of 19.2. Mean serum tT level did not vary in patients with LNI as compared with those without LNI; conversely, hypogonadism was found in a significantly greater rate in pN+ patients (Chi2: 6.98; 30.1% vs 19.4%, p=0.008). UVA? At multivariable logistic regression analysis hypogonadism emerged as an independent predictor of LNI (OR 1.81; p=0.03), along with clinical stage (OR 2.02; p=0.04), biopsy Gleason score (OR 14.81; p<0.001) and PSA levels (OR 1.07; p < 0.001). CONCLUSIONS - The results of this study provide evidence that hypogonadism might serve as an independent predictor of LNI in patients with PCa undergoing ePLND.