CALCA and medullary thyroid gland carcinoma: Takami et al. used radioimmunoassay for the first time in normal human plasma CGRP content of 6.7 ± 3.0 pg/ml (M ± SD), while with medullary thyroid carcinoma (MTC) patients with elevated plasma CGRP content, they believe that plasma CGRP is MTC.