Diagnostic Utility of Prostein, Uroplakin II and SATB2 for Diagnosing Carcinoma of Unknown Primary Origin: A Systematic Immunohistochemical Profiling

BACKGROUND/AIM: Immunohistochemistry was used to evaluate 600 carcinomas of major histological types from various organs to determine the tissue distributions of the novel markers prostein, uroplakin II and SATB2. MATERIALS AND METHODS: We retrieved 30 cases from 20 different carcinomas of systemic organs. RESULTS: All prostate adenocarcinomas were immunopositive for prostein, and its reactivity was consistently diffuse. There was faint labeling of prostein in few cases of the 570 non-prostatic carcinomas. Uroplakin II was immunopositive in 53% and 60% of urothelial carcinomas (UC) of the bladder and the ureter, respectively. There was focal and weak positivity of uroplakin II in a few cases of non-urinary tract carcinomas. SATB2 was frequently positive in adenocarcinomas of the digestive organs, and was also expressed in a minority of the non-colorectal adenocarcinomas. CONCLUSION: Prostein and uroplakin II are immunohistochemical biomarkers of prostate adenocarcinomas and UCs of the urinary tract.