Prognostic factors in medullary carcinoma of the thyroid

A good prognosis in medullary thyroid carcinoma (MTC) has been correlated with homogenous immunohistochemical staining using antibodies to calcitonin (CT). Also, for unexplained reasons, multiple endocrine neoplasia (MEN) 2A and sporadic MTC patients had a better prognosis than MEN 2B patients. However, the post-operative serum CT level was not helpful in predicting the prognosis. The aim of this work was to reassess the prognostic factors in MTC, employing these three parameters in 16 patients (6 MEN 2A and 10 sporadic) for a period of more than 15 years. Normalization of post-tumour resection serum CT was associated with significant improvement of survival (P=0.0009) and in the quality of life (P=0.0002). In accordance with previous reports, MEN 2A patients had a better prognosis than sporadic patients. The pattern of immunohistochemical staining was not helpful in assessing prognosis. We conclude that normalization of post-operative serum CT is a helpful and practical tool in assessing the prognosis in MTC patients.