Wolinski K, et al. – In this present study, the diagnostic value of four selected markers — calcitonin (Ct), procalcitonin (PCT), chromogranin A (CgA), and carcinoembryonic antigen (CEA) was compared for detection of recurrence of medullary thyroid cancer (MTC). Findings approved PCT as an equivalent alternative for measurement of calcitonin. However, the diagnostic value of CEA and chromogranin A was much lower and could be within the normal range even in patients with advanced, metastatic MTC. Hence, both of this agents should be used only as accessory markers.