RESUMO
The role of pro-angiogenic marker galectin-3 (GAL-3) was examined in differential diagnosis of follicular neoplasms of thyroid into histological subsets of follicular adenoma (FA), follicular carcinoma (FC) and follicular variant of papillary thyroid carcinoma (FVPTC). The study included 22 cases from January 2006 to June 2011 comprising of FA (n = 12), FC (n = 3) and FVPTC (n = 7). Immunohistochemical evaluation of GAL-3 was performed on representative histologic sections from the resected thyroid specimens. The proportion of stained cells and intensity of staining in tumor blood vessels were evaluated. GAL-3 expression showed that angiogenesis was prominent in malignancy (FC and FVPTC) and negative in non-neoplastic thyroid parenchyma and benign condition (FA). GAL-3 expression was found to differentiate benign from malignant follicular neoplasms. Focal and diffuse positivity for GAL-3 was found to be associated with FC and FVPTC respectively, thus GAL-3 can be used as a immunohistochemical marker in the differential diagnosis of follicular neoplasms of thyroid based on the type of expression. Limitation of this study was relatively less number of cases studied; however, this data need to be corroborated in larger cohort.