RESUMO
Objective To evaluate the expression of alpha-methylacyl-coenzyme-A racemase (AMACR,P504s) with immunohistochemical staining in diagnosis of prostate carcinoma. Methods A total of 133 specimens were taken from the patients (mean age,71 years),including 46 cases of prostate carcinoma (PCa) (1 case of stage A,19 cases of stage B,14 cases of stage C,12 cases of stage D;4 cases of gradeⅠ,14 cases of gradeⅡ,28 cases of grade Ⅲ),53 cases of benign prostate hyperplasia (BPH),13 cases of prostate intraepithelial tumor (PIN),9 cases of normal prostate,6 cases of prostatitis,3 cases of metastatic prostate cancer.Two sections of each specimen were made,with 1 stained by hematoxylin and eosin,and the other stained immunohistochemically by a rabbit monoclonal antibody to AMACR (P504s).AMACR staining expression was characterized as negative (score,1), weak (positive) (2), moderate (3) or strong (4). Results In 46 cases of PCa,AMACR staining expression was negative in 2 cases,weak in 1,moderate in 25 and strong in 18,with a mean staining intensity of 3.28 [95% confidence interval (CI), 3.07-3.50]. In 53 cases of BPH, the staining expression was negative in 47 cases, weak in 6, with a mean intensity of 1.11 (95% CI, 1.02-1.20).In 13 cases of PIN, the staining expression was negative in 12, weak in 1, with a mean intensity of 1.08 (95% CI, 0.91-1.24).The score of PCa group was significantly different from those of the latter 2 groups (P