Calcitonin

Antigen Background

Calcitonin is a peptide hormone produced primarily by parafollicular (C) cells of the thyroid gland and is widely used as a sensitive immunohistochemical and cytological marker of C cell differentiation. Calcitonin is involved in calcium homeostasis through inhibition of osteoclastic bone resorption; however, its greatest clinical and pathological significance lies in its role as a biomarker for C cell hyperplasia and medullary thyroid carcinoma (MTC), where calcitonin expression reflects neuroendocrine differentiation and serves as a key diagnostic, prognostic, and disease‑monitoring tool. It is reported to be expressed in normal thyroid C cells, C cell hyperplasia, and medullary thyroid carcinoma.

Disclaimer

Calcitonin is recommended for the detection of specific antigens of interest in normal and neoplastic tissues, as an adjunct to conventional histopathology using non-immunologic histochemical stains.