Association between RET genotype and disease phenotype in patients with hereditary medullary thyroid carcinoma

Objective To investigate the association between RET genotype and disease phenotype in the patients with hereditary medullary thyroid carcinoma (HMTC). Methods A total of 13 patients diagnosed as HMTC and undergoing surgical treatment for thyroid carcinoma in this hospital from March 2015 to September 2019 were analyzed retrospectively with follow-up cutoff at September 2021. The patient risk stratification was performed according to American Thyroid Association (ATA) guidelines. The association between RET genotype and disease phenotype including biochemical results, TNM stage, both biochemical [normal serum calcitonin(CT)] cure and clinical cure was analyzed. Results There were 1 (7.69%) case, 6(46.15%) cases, and 6(46.15%) cases with the highest risk mutation (RET M918T), high-risk mutation (RET C634Y and C634S), and moderate-risk mutation (RET C618G and C611Y), respectively. One case with the highest risk mutation was at TNM stage Ⅳ. There were 4 cases (66.67%) at stageⅠand 2 cases (33.33%) at stage Ⅲ amo