Prediction of patient outcome in pathologic stage T2 adenocarcinoma of the prostate: lack of significance for microvessel density analysis.

摘要

OBJECTIVES: Some patients with palpable intermediate- and high-grade, margin-free, organ-confined prostate cancer experience recurrence following prostatectomy. We studied the ability of microvessel density and other factors to predict recurrence in such patients with pathologic Stage T2 cancer. METHODS: Between 1987 and 1991, 307 patients underwent radical prostatectomy for Gleason score 6 to 9, margin-free, organ-confined prostate cancer at Mayo Clinic, Rochester, Minnesota. Specimens from 147 patients with sufficient cancer tissue for immunohistochemical staining with Factor VIII-related antigen were studied by computer-assisted digital image analysis for optimized microvessel density (OMVD). The correlation of deoxyribonucleic acid (DNA) ploidy, Gleason score, OMVD, unilateral disease, bilateral disease, and preoperative prostate-specific antigen (PSA) to cancer recurrence was assessed using the Cox model. Biochemical recurrence was defined as postoperative increase in PSA of greater than 0.2 ng/mL, and clinical recurrence was defined as positive biopsy or metastasis on bone scan. RESULTS: Mean follow-up for all patients was 6.1 years, with 12 deaths (1 due to prostate cancer) and 58 cases of clinical and/or biochemical recurrence. OMVD was not significantly associated with DNA ploidy, Gleason grade, unilateral disease, bilateral disease, or preoperative PSA. Preoperative PSA was the strongest predictor of clinical and/or biochemical recurrence in both univariate and multivariate analysis. OMVD was not a significant univariate or multivariate predictor of clinical and/or biochemical recurrence. The estimated relative risk of clinical and biochemical recurrence associated with a change in OMVD from the 25th percentile (OMVD 45) to the 75th percentile (OMVD 84) was 1.08 (95% confidence interval 0.79 to 1.47). CONCLUSIONS: Preoperative PSA was the strongest predictor of clinical and/or biochemical recurrence of prostate cancer in this group of patients. Optimized microvessel density did not predict outcome in a select cohort of patients with palpable intermediate- and high-grade, margin-free, organ-confined prostate cancer (TNM stage T2N0M0).