EXPRESSION OF GALECTIN-3 IN THYROID NEOPLASM.

BACKGROUND Thyroid cancer is the most common malignant endocrine cancer worldwide. The diagnosis and distinction between benign and malignant thyroid neoplasm, especially in follicular patterned thyroid lesions is still difficult. Of the various immuno histochemical markers, Galectin-3 was most reliable in diagnosis of thyroid carcinoma. AIM To study diagnostic utility of Galectin-3 in thyroid neoplasm. METHODS This was laboratory based diagnostic study, where 92 cases of thyroid neoplasm (48-malignant and 44 benign) were analyzed for Galectin-3 expression. The Galectin-3 staining was quantitatively evaluated as percentage of positive tumor cells and qualitatively for intensity of staining. When membrane ± cytoplasmic immunoreactivity of Galectin-3 was present in more than 10% of tumor cells was considered as positive staining. RESULTS Galectin 3 expression was significantly higher in thyroid cancer as compared to benign thyroid neoplasm (p<0.001). 33/35 cases of PTC were positive for Galectin-3 expression. Galectin-3 expression was significantly higher in FTC as compared to FA (p <0.01). Galectin-3 was also useful to differentiate between FVPTC and FTC (p<0.01) and FVPTC from other benign neoplasm (<0.01).The sensitivity, specificity, positive predictive value and negative predictive value in differentiating benign and malignant thyroid neoplasm were 83.33%, 100%,100%, 84.62% respectively. CONCLUSION Galectin-3 is a potential marker in differentiating benign and malignant thyroid neoplasm. It can used as sole marker for differentiating PTC and benign thyroid neoplasm and also useful to differentiate between FVPTC and FTC. [ABSTRACT FROM AUTHOR]