Immunohistochemical expression of GATA3, CK5/6 and CK20 in molecular subtypes of bladder carcinoma: correlation with clinicopathological features

Abstract Background Bladder urothelial carcinoma, is considered the 7th most common cancer in males. It is classified into luminal and basal subtypes depending on molecular markers, influencing prognosis and treatment. Identifying reliable biomarkers like GATA3, CK20, and CK5/6 through immunohistochemical methods can aid in early detection, risk stratification, and personalized treatment strategies. This study aims for evaluation prognostic role of these mentioned markers in correlation with clinicopathological parameters in urothelial carcinomas. Methods Tumor samples of forty cases were immunohistochemically stained for GATA3, CK5/6, and CK20. A cutoff of 20% positivity was used to determine subtype classifications, with staining patterns guiding the categorization into basal, luminal, double positive, or double negative groups. Results In this study of 40 urothelial carcinoma patients tumors were classified into basal and luminal subtypes using GATA3, CK5/6 and CK20 markers. GATA3 expression showed no significant association with clinicopathological parameters; while, CK20 was associated with tumor size, and CK5/6 with T, N classification, and lymphovascular invasion. Significant differences in clinicopathological parameters were observed when subtypes were defined by CK5/6, GATA3 or CK20, particularly in tumor grade, T and N classification, and gender. Basal molecular subtypes was correlated with poor prognostic parameters. Conclusions This study documented that use of triple markers could define the luminal and basal subtypes of urothelial carcinoma. Basal tumors have shown to be associated with the aggressive behavior and future studies may allow the development of new therapies in the context of molecular subtypes.