Is there a predictive value for measurement of tumor percentage and the number of tumor foci after prostatectomy?

Abstract

159 Background: The prognostic relevance of tumor volume (TV), tumor percentage (TP) and number of tumor foci (NF) as predictors of biochemical recurrence (BCR) in prostate cancer (PCA) following radical prostatectomy (RPE) is controversial. Methods: The cohort consisted of 758 referred subjects who underwent RPE between 2000 and 2005 at the University of Muenster. The mean time of follow up was 62 months. TV, TP and NF were estimated visually with the assistance of a pathologic mapping grid for embedded RPE specimens. In addition, TV and TP were assessed in a categorized fashion by using medians as cut points. Subgroup analyses for high (i.e. any of the following: > pT2, Gleason score ≥ 8, PSA > 20 ng/ml) and low risk (not high risk) patients were performed. Univariate and multivariate Cox propotional hazard analyses for BCR were performed. Results: TV, TP, and NF were strongly related to tumour stage, Gleason score, surgical margin status (SM) and preoperative prostate specific antigen (PSA). In univariate analysis all pathologic parameters including TV, TP, and NF were predictive for BCR. In multivariate analysis only TP, tumour stage, Gleason score, and PSA level were independent predictors. In subgroup analysis, TP was an independent predictor for BCR in the high risk group, but not in the low risk group. Conclusions: TP, but not TV or NF was found to be an independent predictor for BCR in patients after RPE. TP seems to be more relevant in high risk patients.