Medullary thyroid cancer is a tumor of the thyroid C cells that occurs
in sporadic and hereditary clinical settings. Genetic testing of at-r
isk individuals is available and has been applied to patient managemen
t. Plasma calcitonin levels are a very sensitive marker for the presen
ce of disease. Surgery offers the best hope for cure and also is an ef
fective modality for managing metastatic and recurrent disease.