Surgical Therapy and Prognostic Factors in Medullary Thyroid Carcinoma (MTC). Current Evaluation of the German MTC Study Group

Abstract

Background: A retrospective study of 946 patients with medullary thyroid carcinoma (MTC) was carried out by the German MTC Study Group. Material and Methods: By questionnaire, data from 42 co-operating centres were collected and computerized. There were 714 patients with sporadic MTC (75%) and 232 (25%) with familial disease. Details of the surgical procedures were documented from 433 patients. Results: 604 patients out of 946 are still alive (63.8%), 174 patients died (18.4%), many of them from tumour recurrency (n = 96); further information of 168 patients (17.8%) is missing. A total of 711 patients were followed up 1-278 months. The overall age-adjusted 5-year survival rate was 94% (men 93%, women 96%), the 10-year rate was 85% (men 74%, women 92%). In the first surgery, total thyroidectomy (TT) was done in 354 of 433 patients (81.8%); additionally, lymphadenectomy (LA) of various extent was performed in 48.5%. If diagnosis was known pre-operatively, rates of TT and LA were remarkably higher: 88.3% for TT and 76.5% for LA. For 271 patients the TNM classification was available; of these 51, 104, 92 and 24 presented at stages I, II, III and IV, respectively. In uni- and multivariate analyses, tumour stage and sex are the main risk factors; the form of tumor (sporadic/familial) and age are not significant. Conclusion: In MTC, surgery is the main factor of therapy. Total thyroidectomy and standardized systematic lymphadenectomy are considered to be the treatment of choice.