OA-519 (FATTY-ACID SYNTHASE) AS AN INDEPENDENT PREDICTOR OF PATHOLOGICAL STAGE IN ADENOCARCINOMA OF THE PROSTATE

Objectives. To improve the prediction of pathologic stage beyond that provided by Gleason score. Methods. We investigated the tissue express ion in prostate cancer of a relatively new marker, oncoantigen 519 (OA -519). Because Gleason score is one of the most powerful predictors in prostate cancer, we restricted our evaluation to 66 radical prostatec tomy specimens of varying pathologic stages which were either Gleason score 6 or 7. Immunohistochemical staining of OA-519 was assessed with a combined staining score from 0 to 8, taking into account both the i ntensity and percentage of tissue staining. In addition, an intensity score was derived based on whether any intense staining was present in a case. Results. OA-519 staining of the primary prostate cancer was h ighly predictive in separating cases with organ-confined disease or ca psular penetration versus cases with seminal vesicle invasion or lymph node metastases; Gleason score 6 or 7 was also predictive. In a logis tic multivariate regression analysis, both OA-519 and Gleason score we re strong independent predictors of pathologic stage (P = 0.0004). Con clusions. OA-519 predicted pathologic stage well when analyzing primar y prostate cancer in radical prostatectomy specimens and is presently being investigated on preoperative biopsy material to assess its ultim ate clinical applicability. OA-519 has significant promise as a progno stic marker for prostate cancer and is one of the few markers that pro vides additional predictive information beyond that of the Gleason sco re.