Diagnostic utility of Alpha Methylacyl CoA Racemase in prostatic adenocarcinoma: An institutional experience

Abstract

P504S is a prostate cancer specific gene that encodes for ?-methylacyl CoA racemase (AMACR). AMACR has been shown to be selectively over expressed in prostatic adenocarcinoma with minimal to undetectable expression in benign prostatic tissue. We studied the expression of AMACR in 30 cases of prostatic adenocarcinoma using polyclonal anti-AMACR antibody and correlated it with Gleason score. Extent of staining/proportion score (0: no positive cells; 1+:1-10% positive cells; 2+11-50% positive cells; 3+>50% positive cells) was also recorded and correlated with Gleason score. All the 30 cases showed strong, cytoplasmic granular AMACR staining irrespective of their Gleason score with 26 (86.7%) cases showing immunostaining in more than 50% tumor cells (3+ proportion score). Benign prostate tissue adjacent to adenocarcinoma showed negative AMACR staining. No correlation was seen between Gleason score and AMACR proportion score. We concluded that AMACR is a highly sensitive positive marker of prostatic adenocarcinoma. Keywords: Prostate adenocarcinoma, Gleason score, AMACR.