A Clinical Study of Prognositc Factors in Medullary Thyroid Cancer

Kim, Jeong Han; Woo, Sang Uk; Kim, Sang Wook; Nam, Seok Jin; Seo, Jeong Min; Yang, Jung Hyun

Abstract

PURPOSE
Medullary thyroid carcinoma (MTC) is an uncommon thyroid tumor and calcitonin (CT) is its specific tumor marker. The aim of this study was to evaluate the outcome of surgical treatment for MTC and to identify the prognostic factors for normalization of CT after surgery. METHODS: Retrospective analysis of 38 patients operated for MTC from 1994 to 2003 in Samsung Medical Center was done. RESULTS: There were 28 female and 10 male patients, with the mean age 46.7 years. The mean follow-up period was 46.1 months. Eight patients showed signs of multiple endocrine neoplasia syndrome, and 30 patients (78.9%) were preoperatively diagnosed as MTC. Total thyroidectomy with/without neck dissection was performed in all the patients, and metastasis to cervical lymph nodes was detected in 36.1% of these patients. Basal CT levels in of 20 patients (52.6%) normalized postoperatively. One distant metastasis, 8 loco-regional recurrences and 1 lethal outcome were noted during the follow-up period. When thyroidectomy and lateral neck dissection were performed primarily in patients with no evidence of nodal metastasis, basal CT levels decreased to normal levels in 100% compared with 63.2% in patients treated only with thyroidectomy with/without central neck node dissection. Gender, extra-thyroidal invasion, involvement of lymph nodes and the level of preoperative CT were significant prognostic factors for normalization of postoperative CT in univariate analysis. CONCLUSION: In view of a better chance of normalization of postoperative CT, dissection of lateral neck as well as central compartment should be considered as a primary operation in patients with MTC.