GATA3 expression in metastatic urothelial carcinoma in fine needle aspiration cell blocks: a review of 25 cases.

GATA binding protein 3 is a zinc finger transcription factor with high affinity for urothelial tissue and is a promising immunohistochemical marker in detection of urothelial carcinomas (UC). We studied its usefulness in metastatic high-grade UC. This study was performed on cell blocks (CB) of fine needle aspirates from 25 cases of metastatic high-grade UC in patients with previously resected high-grade UC. Immunohistochemical staining for GATA3, thrombomodulin, uroplakin, cytokeratin 7, and cytokeratin 20 was performed. Twenty-three of 25 cases of metastatic UC expressed GATA3 (92%); positive staining for cytokeratin 7 was present in 23 of 25 cases (92%), 20 of 25 (80%) stained for thrombomodulin, and 13 of 25 (52%) stained for cytokeratin 20. No case expressed uroplakin. Five hundred forty-seven non-urothelial carcinomas, including breast ductal carcinoma (77), hepatocellular carcinoma (100), colonic adenocarcinoma (81), pancreatic adenocarcinoma (28), gastric adenocarcinoma (31), endometrial carcinoma (27), ovarian serous carcinoma (27), lung adenocarcinoma (27), lung squamous cell carcinoma (26), malignant melanoma (27), renal cell carcinoma (48), and prostatic adenocarcinoma (48) in tissue microarrays were also analyzed and were GATA3 negative except for 35 of 77 (45.5%) of GATA3 positive breast ductal carcinoma. GATA3 has high sensitivity and specificity for detection of metastatic UC and thus may play an important role in diagnosing metastatic UC in CB samples.