Clinical understaging in patients with prostate adenocarcinoma submitted to radical prostatectomy: predictive value of serum chromogranin A.

PURPOSE To evaluate whether the pretreatment determination of serum chromogranin A (CgA) can provide information beyond that obtained with serum prostate specific antigen (PSA) and Gleason score at biopsy as a predictive factor of clinical understaging (T2-pT3) of prostate adenocarcinoma. MATERIALS In this prospective study, we analyzed 83 consecutive patients with clinical T2N0M0 prostate adenocarcinoma submitted to radical prostatectomy (RRP). On the same day of RRP, before surgery, a blood sample for the determination of serum total PSA and CgA levels (RIA) was obtained. RESULTS After RRP, 27 of the 83 cases (32.5%) showed extracapsular disease extension (pT3) at the final pathological examination and were considered clinically understaged. A significant association between serum CgA and pathological stage (r = 0.3830; P = 0.0004) was found. At the multivariate analysis, serum CgA and PSA, but not biopsy Gleason score, were found to be significant pretreatment independent predictors of pT3 at RRP (P = 0.00004 and P = 0.0018, respectively). The relative risk of clinical understaging significantly varied according to serum CgA levels. Using a CgA cut-off value of 60 ng/ml, PPV and NPV for clinical understaging were 0.5161 and 0.7885, respectively (P = 0.0072). CONCLUSIONS Serum CgA could be incorporated into risk assessment models of newly diagnosed prostate cancer.