BACKGROUND: The cancer of the thyroid gland is characterized by its clinical and pathological variety. The difficult preoperative diagnosis of the follicular lesions lead to more surgical procedures of diagnostic characteristic than therapeutic. The aim of this study was to identify the immunohistochemical expression of the thyroid epithelial neoplams using monoclonal antibodies for galectin-3 and cytokeratin 19, and correlate them with pathological variables. MATERIAL AND METHODS: The expression of galectin-3 and cytokeratin 19, was immunohistochemically studied in 84 cases with diagnosis of normal tissue (n = 10), adenomatoid goiter (n = 8), follicular adenoma (n = 12), Hürthle cell adenoma (n = 3), papillary carcinoma (n = 29), follicular carcinoma (n = 8), poorly differentiated carcinoma (n = 4), Hürthle cell carcinoma (n = 4), anaplastic carcinoma (n = 6), which were selected from patients treated at the Head and Neck Surgery Department of Hospital Heliópolis, from 1984 to 1995. RESULTS: The expression of galectin-3 was observed in the cases of adenomatoid goiter (12.5%), follicular adenoma (16.7%), papillary carcinoma (96.6%), follicular carcinoma (50%), Hürthle cell carcinoma (100%) and anaplastic carcinoma (50%). Our results confirmed the significant expression of galectin-3 in the group of the malignant neoplasms, mainly in the papillary carcinoma. The expression pattern of cytokeratin 19 was different among the types of lesions; whereas in the goiters and adenomas it was weak, in the papillary carcinomas it was strong and diffuse. CONCLUSIONS: Galectin-3 and cytokeratin 19, associated, help the histopathological diagnosis, mainly in the lesions of difficult interpretation; besides they highlight atypical conditions and, thus, determine a suspicious lesion.
Immunohistochemistry; Thyroid neoplasms; Pathology; Galectin-3; Cytokeratin 19
