[The importance of clinical and histologic variables in the prognosis of medullary carcinoma of the thyroid gland].

Patients with medullary thyroid carcinoma (MTC) have aroused considerable interest ever since Horn (1951), Hazarde et al. (1959) and Williams (1966) described MTC as a separate clinicopathologic entity, because this tumor occurs both in families and in association with neural and endocrine abnormalities. This interest also underlines our clinicohistologic study of 31 patients with a histologically demonstrated MTC. The patients have been analyzed at the Central Institute for Tumors and Allied Diseases in Zagreb from 1969 to 1988. The youngest patient was 17, and the oldest one 85 (average 45 years). None of the patients had thyroid carcinoma in his/her family history, or any association with pheochromocytoma or multiple skin and mucosal neurinoma. The men to women ratio was 1:0.94. The prognostic significance of some clinical and histologic variables in patients affected by medullary thyroid carcinoma have been studied. Treatment involved total thyroidectomy with or without neck dissection. Some of the patients were subsequently irradiated or administered chemotherapeutic agents. The data obtained in the study were statistically processed and the statistical differences between the survival rates of the various patient groups were determined by the logrank-test. Of the studied variables (sex, age, tumor size, cervical metastases, tumor structure, cell type, stroma, calcification, number of mitoses, necrosis, bleeding, amyloid content), the following were found to have a prognostic significance: age, tumor size and regional lymph node metastases.