Diagnostic utility of p63 and α-methyl acyl Co A racemase in resolving suspicious foci in prostatic needle biopsy and transurethral resection of prostate specimens

Aim of the Study: The objective is to assess the utility of the p63 and α-methylacyl CoA racemase (AMACR) in resolving suspicious foci in prostatic needle biopsy and transurethral resection of prostate (TURP) specimens. Materials and Methods: A total of 470 cases are selected. These included 310 TURP specimens, 157 needle biopsies and 03 radical prostatectomy specimens. All the cases are reviewed and divided into three categories. Benign (370), cases with suspicious foci (40 cases) and malignant (60 cases). Immunohistochemistry (IHC) was carried out using monoclonal AMACR and p63 antibodies in the 40 suspicious cases along with positive and negative controls. Results: This study showed AMACR had a sensitivity of 95%, specificity of 92.5%, whereas p63 had a sensitivity of 90%, specificity of 100%. All the 40 suspicious cases were resolved using a combination of morphology and IHC expression p63 and AMACR. In 13 (32.5%), of the 40 suspicious cases there was change of diagnosis based of morphology, clinical details and staining with p63 and AMACR, In the 11 cases (11/40), diagnosis was changed from the benign to malignant. In one case benign to high grade prostatic intraepithelial neoplasia (1/40) and in one case from malignant to benign (1/40). This change was statistically significant with P value of 0.013. Conclusions: Combination of p63 and AMACR is of great additional value in combating the morphologically suspicious cases and should be used on case to case basis especially in prostatic needle biopsies and small foci lesions.