Use of Systematic Biopsy Results to Predict Pathologic Stage in Patients with Clinically Localized Prostate Cancer: A Preliminary Report

Abstract

Background: The purpose of this study was to determine the ability of clinical tests to predict advanced pathologic stage (seminal vesicle invasion, pT3c, or pelvic lymph node metastases, pN+). Methods: T stage, PSA, PSA density, and pathologic features in systematic biopsy specimens were correlated with pathologic stage in 190 consecutive patients with clinically localized (T1‐3) prostate cancer detected by systematic needle biopsies and treated with radical prostatectomies. Results: Thirty‐three patients (17%) had an advanced pathologic stage cancer (pT3c or pN+). In logistic regression analysis, the total length of cancer in all biopsy cores (P < 0.0005), the percent of poorly‐differentiated cancer in each specimen (P < 0.021), and serum PSA (P < 0.028) were the only significant predictors of advanced stage. A model was constructed to predict advanced stage: if the PSA was 6 ng/mL and 4 or more biopsy cores were positive and the total length of cancer in all cores was 20 mm and at least 10% of the cancer was poorly‐differentiated, then 14 (93%) of 15 patients had an advanced pathologic stage cancer compared to 11% of the remaining 175 patients (P < 0.0005). Conclusion: The pathologic features of cancer in systematic needle biopsy specimens more accurately predicts which patients have advanced stage cancer than standard clinical tests alone.