MEDULLARY-THYROID CARCINOMA - CLINICAL-FEATURES AND LONG-TERM FOLLOW-UP OF 78 PATIENTS TREATED BETWEEN 1969 AND 1986

This article describes the findings of a retrospective analysis of dat a obtained on 78 patients with medullary thyroid carcinoma (MTC), reco rded between 1969 and 1986, and then followed at the Thyroid Center of Padua (Italy). The ages of the patients ranged between 15 and 89 year s, with a median age of 45. The female to male (F : M) ratio was 2.9 : 1. All patients except 2 had total thyroidectomy. In 70 cases the tum or was of sporadic type; there were 3 familial non-multiple endocrine neoplasia (MEN) MTC; 3 MEN IIa; and 2 MEN IIb. The median duration of follow-up was 15.9 years (13 patients were followed up between 15 and 20 years, and 9 longer than 20). At diagnosis, the tumor was intrathyr oid (stage I and II) in 31 patients, with local lymphnodes involved (s tage III) in 41 patients, and with distant metastases (stage IV) in 6 patients. A total of 34 patients died (4 were at stage II at diagnosis , 26 at stage III, and 4 at stage IV); 4 of them died of unrelated cau ses, the others with tumor. The median survival rate of the deceased p atients was 6 years (41% of these patients died within 3 years and 24% after more than 10 years); 76% of the deceased patients were older th an 45 years at diagnosis. A total of 44 patients are still alive, 22 a re alive free of disease (with follow-up between 10 and 24 years, medi an 14.2 years) and 22 are alive with disease (median follow-up 12.2 ye ars). Only 30% of the patients of both these groups was older than 45 years at diagnosis. Survival is strongly related to tumor stage and to age at diagnosis, because only 8 of the 34 deceased patients were you nger than 45 years (and 2 of them died of unrelated causes); moreover, patients who were treated at earlier stages of the disease had better prognosis. Survival rate at 10 and 20 years was 95% for patients with tumor limited to the thyroid, whereas it was 55% and 28.6%, respectiv ely, for patients at stage LII and IV. Bone metastases were correlated with worse prognosis than distant metastases only to soft tissues. Th e sex did not affect survival. None of the patients who had postoperat ive low serum calcitonin (CT) levels and no response to pentagastrin s timulation showed recurrences in the follow-up. In patients with posto perative elevated serum CT levels, recurrences of the tumor increased over time. However, 30% of these patients continued to show only eleva ted CT levels without evidence of the disease, even after 15 years.