Indications for preoperative seminal vesicle biopsies in staging of clinically localized prostatic cancer

Objective: To identify patients at high risk of extraprostatic seminal vesicle infiltration, in whom preoperative seminal vesicle biopsies should be performed. Materials and Methods: We studied the relationship between extraprostatic seminal vesicle infiltration and the available preoperative data [age, clinical stage, prostate-specific antigen (PSA) level, number and site of positive prostatic sextant biopsies, Gleason score] in a total of 75 patients suffering from clinically localized prostatic adenocarcinoma who were candidates for radical prostatectomy. Results: The chi(2) test showed that the preoperative data most significantly correlated with extraprostatic seminal vesicle infiltration were the presence of positive basal biopsies (p < 0.001). The PSA level did not have any predictive value. The most discriminant preoperative parameter of the state of the seminal vesicles (analysis of variance on a univariate model) was the state of the basal prostatic biopsies. The importance of this parameter was confirmed by cluster analysis. Overall, the risk of extraprostatic seminal vesicle invasion was 0 (0/21 patients) when the 2 basal prostatic biopsies were negative, 10.25% (4/39 patients) when 1 of the 2 basal prostatic biopsies was positive and 73.33% (11/15 patients) when both basal prostatic biopsies were positive. Conclusions: In a patient with clinically localized prostatic adenocarcinoma who is a candidate for radical prostatectomy, seminal vesicle biopsies are useless when basal prostatic biopsies are negative, regardless of the state of other preoperative parameters. When 1 or 2 basal prostatic biopsies are positive, seminal vesicle biopsies can improve the pretreatment pathological staging.