MP15-11 RISK FACTORS FOR UPSTAGING IN PATIENTS WITH LOW RISK PROSTATE CANCER USING K-CAP REGISTRY

INTRODUCTION AND OBJECTIVES: We evaluated the preoperative clinical factors associated with pathologic upstaging in radical prostatectomy specimens in patients with low risk prostate cancer. METHODS: Among 3,206 prostate cancer patients in K-Cap Registry, 659 (20.6%) patients were determined as patients with clinically low risk prostate cancer. Pathologic upstaging was defined as pathologic T3a or greater on specimens after radical prostatectomy. Preoperative factors associated with pathologic upstaging were identified using multivariate analysis. In addition, the role of magnetic resonance imaging (MRI) in low risk prostate cancer was also identified using multivariate analysis. RESULTS: Mean age was 63.0 years and PSA level was 5.4 ng/mL. Prostate volume was 39.4 cc. Pathologic upstaging was observed in 94 (14.5%) patients. Seminal vesicle invasion was observed in 6 (0.9%) patients. In multivariate analysis, age (OR; 1.040, p1⁄40.026), prostate volume (OR; 0.978, p1⁄40.011) and PSA (OR; 1.211, p1⁄40.002) were identified as risk factors for pathologic upstaging. Preoperative MRI was performed in 505 (76.6%) patients. Among these patients, locally advanced disease was suspicious on preoperative MRI in 78(15.3%) patients. Sensitivity and specificity of MRI on pathologic upstaging was 84.6% and 97.2%, respectively. If preoperative MRI was performed, suspicious locally advanced disease on MRI was the only risk factor for pathologic upstaging after radical prostatectomy in the low risk prostate cancer. CONCLUSIONS: In patients with low risk prostate cancer, age, prostate volume and PSA level is preoperative variables associated with pathologic upstaging after radical prostatectomy. Preoperative MRI could be regarded as an useful diagnostic tool for detecting locally advanced disease in patients with low risk prostate cancer.