Combined modality staging of prostate carcinoma and its utility in predicting pathologic stage and postoperative prostate specific antigen failure

Abstract

Objectives: This study was performed to predict the factors that can optimize preoperative staging for clinically localized prostate cancer patients.

Methods: Logistic and Cox regression multivariable analyses were performed on 480 surgically-managed prostate cancer patients to evaluate the ability of clinical stage, prostate specific antigen (PSA), biopsy Gleason sum, percent positive biopsies, and endorectal coil magnetic resonance imaging (erMRI) results to predict for pathologic established extracapsular extension (ECE), seminal vesicle invasion (SVI), and time to postoperative PSA failure.

Results: The characteristics of clinically organ-confined prostate cancer patients at high risk (> 67%) for postoperative PSA failure within 3 years include: (A) PSA > 20 ng/mL; (B) Biopsy Gleason sum > or = 8; or (C) erMRI positive for extraprostatic disease and intermediate risk disease. For patients at intermediate risk (ie, either a PSA < 4 and biopsy Gleason sum of 7; PSA > 4 to 10 ng/mL and biopsy Gleason sum 5 to 7; or a PSA > 10 to 20 ng/mL and biopsy Gleason sum 2 to 7), despite 100% positive biopsies, 50% of patients had pathologic organ-confined disease. However, in the subset of intermediate-risk patients with a positive erMRI for either ECE or SVI and at least 50% positive biopsies, all had extraprostatic disease and failed biochemically by 47 months postoperatively. Intermediate-risk patients with < 50% positive biopsies had pathologic organ-confined disease in at least 77% of the cases.

Conclusions: Combined modality staging using the PSA, biopsy Gleason sum, percent positive biopsies, and endorectal coil MRI findings in select patients can predict pathologic stage and postoperative PSA failure. Therefore, this combined modality staging may optimize patient selection for phase 3 trials examining the role of neoadjuvant androgen ablative therapy for patients with clinically localized disease.