CA19-9 as a Predictor of Worse Clinical Outcome in Medullary Thyroid Carcinoma

Objective Medullary thyroid carcinoma (MTC) is a rare disease, and its classic tumor marker is calcitonin. However, recently, very aggressive cases have been reported to also secrete carbohydrate antigen 19-9 (CA19-9), and its role as a marker of worse prognosis has been questioned. The aim of this study was to analyze the relationship between CA19-9 serum levels and MTC outcomes.