Tumor Focality Does Not Predict Biochemical Recurrence After Radical Prostatectomy in Men With Clinically Localized Prostate Cancer

Abstract

We characterized prostate cancer focality in regard to clinicopathological features, prognostic value and impact on biochemical outcome. We retrospectively reviewed the records of 1,366 patients in our prospective database who underwent radical prostatectomy between 1999 and 2010 for clinically localized prostate cancer with pathological evaluation using whole mount sectioning techniques and tumor mapping. Unifocal disease was defined as the identification of a solitary cancer focus in the prostate without additional tumor foci or satellite lesions, ie multifocal disease, on histopathological evaluation. Cox regression modeling was used to identify predictors of biochemical progression among groups. A total of 184 patients (13%) fulfilled our unifocal tumor criteria. Unifocal tumors tended to be smaller in volume and in greatest diameter than multifocal tumors (p<0.0001 and <0.005, respectively). Of patients with pathologically insignificant disease the relative proportion with unifocal tumors increased to 28% from 13% in the overall cohort (p<0.0005). Also, tumor focality failed to predict biochemical recurrence in univariate and multivariate models. Accordingly we noted no significant differences in 5-year biochemical recurrence-free survival for unifocal and multifocal tumors (66% and 61%, respectively, p=0.76). Limitations of this study include its retrospective nature. In this study tumor focality failed to predict patients likely to experience biochemical failure. Tumor characteristics were similar regardless of focality. However, unifocal tumors had smaller volume and were more commonly seen as clinically insignificant compared to multifocal tumors.