Diagnostic value of selected biochemical markers in the detection of recurrence of medullary thyroid cancer - comparison of calcitonin, procalcitonin, chromogranin A, and carcinoembryonic antigen.

Introduction: Medullary thyroid cancer (MTC) is a malignancy of the thyroid gland, which derives from parafollicular C cells. Periodic measurement of biochemical markers of MTC remains a crucial part of patient follow-up and disease monitoring. The aim of the study was to compare the diagnostic value of four selected markers - calcitonin (Ct), procalcitonin (PCT), chromogranin A (CgA), and carcinoembryonic antigen (CEA).