The calcitonin gene encodes a family of peptides, at least three of which normally circulate in man: calcitonin (CT), a calcium-lowering hormone; katacalcin (KC), a peptide of unknown function; and calcitonin gene-related peptide (CGRP), a neuropeptide and potent vasodilator. In a study of 45 patients with medullary thyroid carcinoma (MTC), plasma CGRP was elevated in approximately 50% of cases. Furthermore, CGRP levels did not correlate with CT levels. However, plasma KC was elevated in all cases, with a good correlation with CT levels, as has been noted previously. Measurement of CT or KC appears to be superior to measurement of CGRP for the detection of MTC.
Girgis, Samia I.; Lynch, Catherine; Hillyard, Carmel J.; Stevenson, John C.; Hill, Patricia A.; MacDonald, David W. R.; and MacIntyre, Iain
"Calcitonin Gene Peptides: The Diagnostic Value of Measurement in Medullary Thyroid Carcinoma,"
Henry Ford Hospital Medical Journal
: Vol. 35
Available at: https://scholarlycommons.henryford.com/hfhmedjournal/vol35/iss2/10