Calcitonin, carcinoembryonic antigen and neuron-specific enolase in medullary thyroid carcinoma.

Calcitonin, carcinoembryonic antigen (CEA) and neuron specific enolase (NSE) were studied in the thyroid glands of patients with multiple endocrine neoplasia (MEN) type 2a, 2b, and with sporadic thyroid carcinomas (MTC). Calcitonin, CEA and NSE were localized in normal C-cells, hyperplastic C-cells, and in MTC. While the distribution of calcitonin and CEA was quite similar in most cases, a smaller proportion of cases were positive for NSE. C-cell hyperplasia was identified in all nine patients with MEN 2a and in four of six patients with MEN 2b. None of the four patients with sporadic MTC had C-cell hyperplasia. These results indicate that C-cell hyperplasia is present in patients with MEN 2a and 2b and that NSE in addition to calcitonin and CEA is a useful marker for the thyroid C-cells.