Ectopic Secretion of Calcitonin by Oat-Cell Carcinoma

Abstract
SEVERAL humoral substances are ectopically produced by cancer tissue.1 2 3 Bronchogenic cancer —in particular, oat-cell carcinoma of the lung — appears to be "multipotential" in this regard. Calcitonin, the hypocalcemic hormone normally produced by the C cells of the thyroid, may now be added to the list of hormones that may be elaborated by this tumor.We have developed a radioimmunoassay for human calcitonin,4 which we have used in a prospective study of normocalcemic patients with bronchogenic carcinoma of several cell types. More than 50 per cent of the patients studied had plasma calcitonin levels above 400 pg per milliliter. We . . .