ABSTRACT
Aims: This study aims to explore the utility of GATA binding protein 3, a zinc finger transcription factor, expression in genitourinary carcinoma, especially urothelial carcinoma. Settings and Design: It is a prospective study where 74 consecutive cases of urothelial carcinoma along with 10 cases each of prostatic adenocarcinoma (PC) and conventional clear cell renal cell carcinoma were included between August 2016 and January 2017. Methods and Materials: All the cases were histopathologically evaluated and immunohistochemically stained for GATA binding protein 3. Only nuclear positivity was considered as positive. Immunoreactivity score for GATA expression was calculated based on the staining intensity as well as percentage. Statistical Analysis Used: The statistical analysis was done using Statistical Package for Social Sciences Version 15.0 statistical analysis software. P value of <0.05 was considered statistically significance. Results: GATA3 expressions were seen in 77% of the cases of urothelial carcinoma, whereas none of the clear cell renal cell carcinoma and prostatic adenocarcinoma cases was GATA3 positive. GATA3 expression significantly correlated with histological grade and muscle invasion with a weaker or negative expression in high-grade muscle invasive tumor as compared to low-grade and noninvasive neoplasm. Significantly weaker expression of GATA3 was found in cases with severe nuclear pleomorphism, mitosis >10/10 hpf, presence of necrosis, and tumor-infiltrating lymphocytes. No significant change in the status of GATA3 expression was seen in follow-up cases between initial Transurethral resection of bladder tumor (TURBT) and post-recurrence TURBT or radical cystectomy specimens. Conclusions: GATA3 as a sensitive and specific marker for urothelial carcinoma can be effectively used to exclude other genitourinary malignancies, PC, and renal cell carcinoma, at metastatic site. This marker can also be effectively used in predicting the probable grade and invasion in biopsy material with poor morphological characteristics, thereby helping in appropriate management in such cases.