Objective: To determine the ability of clinical tests to predict extraprostatic cxtension and seminal vesicle invasion.
Methods: Clinical T stage, TPSA total prostate specific antigen and pathologic features in systematic biopsy specimens were correlated with pathologic stage in 40 consecutive patients with clinically localized prostate cancer detected by systematic needle biopsies and treated with radical prostatectomy.
Results: Extraprostatic extension was observed in 20 patients (50%) and seminal vesicle invasion was noted in 11(28%). Preoperative variables predictors of extraprostatic extension and seminal vesicle invasion on univariate analysis were TPSA, Gleason score, the total length of cancer, the number of positive cores, the percentage of positive cores, the maximum length of cancer in any one core in the biopsy specimen and the percentage of cancer in the biopsy set P<0.05 . In multivariate analysis, TPSA, Gleason score, the total length of cancer and the percentage of positive cores in the biopsy specimens were the only significant predictors of extraprostatic extension and seminal vesicle invasion P<0.01 . A model was constructed to predict advanced stage: the TPSA >or=11 microg x L(-1) and Gleason score/5 and percentage of positive cores in the biopsy specimen >or=27% or the total length of cancer>or=7.3 mm P<0.001 .
Conclusion: The combination of TPSA, the total length of cancer, Gleason score and percentage of positive cores in the biopsy specimens provides the best prediction of capsular perforation and seminal vesicle invasion. Models based on this combination of factors may be clinically useful to stratify patients for nonoperative treatment.