Medullary thyroid carcinoma: prognostic factors.

Medullary thyroid carcinoma is an uncommon cancer of the thyroid gland. It comprises a neuroendocrine tumor of the calcitonin secreting cells. Its level of aggressiveness lies between that of well-differentiated and anaplastic thyroid malignancies. We have undertaken a retrospective study of 18 patients with medullary thyroid carcinoma to evaluate various parameters for their prognostic value. We looked at epidemiologic factors such as stage, age at onset, sex and the heredity of the disease. In addition various immunohistochemical stains were looked at including Leu-M1, calcitonin, thyroglobulin, somatostatin, carcinoembryonic antigen, neuron specific enolase and BRST-1. Finally, DNA ploidy was determined using the flow cytometer. Stage, age at onset, DNA ploidy and staining for BRST-1 were found to be significant factors in determining outcome of this disease.