Immunohistochemical Expression of Nkx3.1 in Prostatic Adenocarcinoma and Benign Prostatic Hyperplasia at a Tertiary Care Hospital in Karachi

OBJECTIVES To determine NKX3.1 expression in prostatic adenocarcinoma and benign prostate hyperplasia on Immunohistochemistry at a tertiary care hospital in Karachi. METHODOLOGY 74 prostatic specimens were recruited in this comparative cross-sectional study at the Department of Pathology, Pakistan Navy Station Shifa Hospital, Karachi, from January 2018 to February 2019. Of these, 37 specimens were of prostatic adenocarcinoma, and 37 were benign prostate hyperplasia. All specimens were subjected to immunohistochemical staining with NKX3.1. Statistical analysis was done by using SPSS version 23.0. The association of the extent of NKX3.1 staining between the adenocarcinoma and hyperplasia group was assessed using the Chi-square test x2. RESULTSOf the 37 cases of benign prostatic hyperplasia subjected to NKX3.1 staining, 32 showed positive staining with strong to moderate intensity. No staining was observed in 5 cases. 37 cases of adenocarcinoma prostate stained for NKX3.1 revealed positive staining in 30 cases with strong to moderate intensity. Negative staining was seen in 7 cases. The prostatic adenocarcinoma showed a statistically significant association of NKX3.1 positivity compared to benign prostatic hyperplasia cases. The p-value was found to be 0.03. CONCLUSION NKX3.1 staining was highly specific for prostate epithelium, as it was positive in most cases. This immune marker was useful for distinguishing prostatic origin in the context of metastatic lesions. Adding NKX3.1 protein staining to a panel of features may add value to the diagnosis if applied in the appropriate clinicopathologic context.