DIAGNOSTIC UTILITY OF IMMUNOHISTOCHEMICAL MARKER, p63 IN PROSTATE BASAL CELLS TO DIFFERENTIATE PROSTATE CARCINOMA FROM BENIGN LESIONS OF PROSTATE

Introduction: Prostate carcinoma (PC) is the fth most common cancer in the world and the is emerging as one of the leading causes of cancer in both developed and developing countries. Needle core biopsies make it very challenging in view of small volume of biopsies and presence of benign mimickers of PC. p63, a basal cell marker for prostatic myoepithelial cells are absent in prostate adenocarcinoma and their identication in prostatic glands can be used to rule out the diagnosis PC. Routine HPE was done Method: along with IHC with p63 on the tissue sections along with positive and negative controls. Out of 57 Results: samples, 19 cases were neoplastic of which 1 case was reported as PIN and remaining 18 cases were malignant. 39 cases were reported as benign. The most common mimicker found was BPH with and without prostatitis accounting to 73.6% cases followed by Basal Cell Hyperplasia and Prostatic Atrophy. 5.8% cases were missed on H&E but showed negative p63 staining indicating PC and 2.5% of benign mimickers were diagnosed as PC on H&E which showed strong nuclear positivity of p63 in suspected malignant glands. In our study, benign lesions showed Conclusion: strong basal nuclear positivity of p63. Malignant cases showed negative nuclear staining in glands but was seen positive in benign glands entrapped in between. The premalignant lesion showed focal and patchy staining by p63. AMACR showed positive in malignant cells but comparatively weak staining was noted in adenocarcinomas having cribriform pattern (Gleason pattern 4). Routine H&E still remains to be the gold standard (94.4%) in diagnosing all PC cases and IHC in an ancillary study done in selected cases only and should not be used as a screening test.