The Expression Of Galectin-3 And Ki-67 In Thyroid Carcinomas And The Value In Differentiating Benign From Malignant Thyroid Neoplasms

Objective1. To detect the expression of Galectin-3 and Ki-67 in benign and malignant thyroid neoplasms.2. To investigate the relationship of Galectin-3 and Ki-67 expression, lymph node metastasis and prognosis of thyroid carcinomas.3. To study the value of Galectin-3 and Ki-67 detection in differentiating benign from malignant thyroid neoplasms.Methods1. Immunohistochemical staining: 67 samples of resected thyroid carcinoma tissues (cancer and adjacent-cancer) and 19 cases of adenomas were examined by streptavidin/peroxidase (S-P) immunohistochemical technique. Sections from human anaplastic large cell lymphoma were used as Galectin-3 positive control.2. Cellular localization: Galectin-3 staining reaction was seen in the cytoplasm, and. Ki-67 was nuclear staining. Immunostaining was evaluated as follows: - , none of neoplastic cells with positivity; +, <25% of neoplastic cells with positivity; ++, from 25% to 50% of neoplastic cells with positivity; +++, >50% of neoplastic cells with strong positivity.Results1. The expression of Galectin-3 in thyroid neoplasms: 59cases of thyroid carcinomas (22/24 follicular carcinomas, 24/27 papillary carcinomas, 10/12 medullary carcinoma and 3/4 anaplastic carcinomas) showed cytoplasmic immunohistochemical staining of Galectin-3, which was diffuse. As to the group of adenomas, only 3 cases were focally and weakly positive. None expression in the tissues of adjacent-cancer.There was significant difference between the expression of Galectin-3 in malignant thyroid tumors and that in benign lesions(P<0.001), and had no difference in four histological types(P>0.05).2. The expression of Ki-67 in thyroid neoplasms: only 5 cases of thyroid adenomas were positive, while 76.12% cases of thyroid carcinomas were positive. There was significant difference between the expression of Ki-67 in malignant thyroid tumors and that in benign lesions(P<0.001), and had no difference in four histological types(P>0.05).3. Among the 43 cases with lymph node metastasis, 41 cases expressed Galectin-3, and 38 cases expressed Ki-67, significantly different with non-lymph node metastasis(P<0.01).4. Among the 37 cases with tumor recurrence, the expression of Galectin-3 and Ki-67 were 97.29% and 89.19%, significantly different with non-recurrence(P<0.05, P<0.025).ConclusionThe results suggest that overexpression of Galectin-3 and Ki-67 play an important role in the thyroid carcinomas. The expression of Galectin-3 and Ki-67 in tumor tissues, is associated with tumor occurrence, progression, metastasis and recurrence in thyroid carcinomas. They may be effective in differentiating benign from malignant thyroid carcinoma, and can be regarded as valuable molecular markers for the tumor progression, recurrence and prognosis.