Prognostic significance of preoperative factors in localized prostate carcinoma treated with radical prostatectomy: importance of percentage of biopsies that contain tumor and the presence of biopsy perineural invasion.

BACKGROUND: Predicting outcome for men with clinically localized prostate carcinoma treated with curative intent remains imprecise and further evaluation of accepted and potential predictive factors is needed.

METHODS: The authors studied 696 men with localized prostate carcinoma diagnosed on transrectal biopsy and treated with radical prostatectomy at one institution between 1986 and 1999 to determine the relation between putative pretreatment prognostic factors and disease-free survival. Clinical stage, Gleason score, perineural invasion, number of biopsies containing tumor, and serum prostate specific antigen (PSA) were evaluated as predictors of extracapsular extension, seminal vesicle involvement, lymph node metastases, and surgical margin involvement as well as outcome after surgery. Kaplan-Meier method and Cox regression analyses were used to evaluate the contribution of different factors to adverse pathologic features and relapse.

RESULTS: At mean follow-up of 56.9 months (range, 1.0-177.9 months; median, 54.9 months), 26.1% (182 of 696 patients) of patients had developed a disease recurrence. Pretreatment serum PSA concentration, biopsy Gleason score, and clinical stage as well as number of biopsies involved with tumor as a percentage of the total number obtained were found to be independent predictors of outcome. In patients with PSA > 10 ng/mL, biopsy perineural invasion and percentage of biopsies containing tumor were found to independently predicted disease recurrent. Increased number of biopsies involved with tumor independently predicted extracapsular extension, margin involvement, seminal vesicle, and lymph node involvement.

CONCLUSIONS: This study demonstrated that the proportion of prostate biopsy cores containing tumor is an independent predictor of outcome after subsequent radical prostatectomy and suggested that perineural invasion has a predictive role in patients with a preoperative PSA > 10 ng/ml.