Medullary carcinoma of the thyroid gland. A clinicopathologic study of 40 cases.

Abstract

The clinical records and pathologic material of 40 patients with histologically proven medullary carcinoma of the thyroid seen at Memorial-Sloan Kettering Cancer Center from 1949-71 were reviewed and analyzed. Patients were 20-75 years old with an average of 47.4 years. There was a 21/19 male to female ratio. A neck mass was the most common presenting sign. Only 3 patients had a family history of thyroid carcinoma; none presented with pheochromocytoma or multiple mucosal neuromas. The histologic appearance of the primary lesions showed a variation in cellular morphology as well as pattern of growth. This variability was not only evident within the primary lesion but in the metastatic sites as well. Many observers are unwilling to diagnose medullary carcinoma in the absence of amyloid deposition and are unaware of the variability in the histologic appearance of this tumor. In those patients having a radical neck dissection as part of the initial therapy or at a later date there was a 66.7% 10-year survival while in the patients not having a radical neck dissection the 10-year survival rate was slightly less than 43%. Several of the cases had multifocal thyroid involvement and 75% had proven cervical lymph node metastases. Therefore it is felt that treatment should include at least a total thyroid lobectomy in conjunction with radical neck dissection. (Authors modified)