Immunohistochemical Expression of Galectin-3 in Thyroid Neoplasms and its Correlation with CD56

Background: The incidence of thyroid cancer has been increasing significantly since the mid-1990s.Some studies have revealed that in thyroid gland, the galectin-3 plays a role in the pathogenesis of well-differentiated carcinoma. For that, it is may be one of the markers that may help to assist in distinguishing thyroid neoplasms. Objective : To detect the frequency of immunohistochemical expression and diagnostic value of Galectin-3 in different types of thyroid neoplasms.To correlate the expression of galectin-3 findings with immunoprofile data of CD56. To correlate the result of immunohistochemical expression of Galectin-3 with the age and gender of the sampled cases.Patients and method: A retrospective case series study was intended in fifty surgically removed cases of primary thyroid neoplasm whose CD56 status had been tested by immunohistochemical technique. The galectin-3 protein was tested on formalin fixed paraffin embedded section by immunohistochemical method using Ab-1, isotype IgG1,clone 9C4 , Mouse Monoclonal Antibody . Results: galectin-3 was positive in 52 % of the cases. Relation of galectin-3 with the histological type of neoplasm and malignant tumors versus benign was significant (P= 0.000152 , P=0.000712 respectively). The galectin-3 was expressed in most of non-follicular pattern (p =0.00001). In this study, 42% of the cases were galectin-3 positive/ CD56 negative and 38% of the cases were galectin-3 negative/CD56 positive, the association of galectin-3 with CD56, was significant (P=0.000023). Conclusion: Galectin-3 immune stain marker considered as a useful marker in differentiating malignant tumors with non-follicular pattern, especially papillary thyroid carcinoma, from a benign tumors. Significant association was found between Galectin-3 and CD56. Galectin-3 can be used as a positive marker while the CD65 is a negative marker for diagnosis of thyroid carcinoma.