“…This is an extremely sensitive indicator for the diagnosis of the disease as reported previously (Tubiana et al, 1968;Melvin et al, 1971;Deftos et al, 1972;Goltzman et al, 1974;Queener and Bell, 1975). Even after the total thyroidectomy, plasma hCT levels were high in 11 out of 16 operated cases, indicating the presence of metastases.…”