Increased serum calcitonin levels in bronchogenic cancer.

A study of 26 men with bronchogenic cancer demonstrated high serum calcitonin levels in 62 percent (16). Levels were particularly high in patients with small-cell cancer and adenocarcinoma. Two varieties of hypercalcitonemia have been encountered: (1) ectopic hypercalcitonemia, in which the hormone is secreted by the tumor, and (2) thyroidal hypercalcitonemia, in which the high values emanate from the thyroid gland. In several patients, serum calcitonin levels decreased following therapy for the cancer. Further studies are needed to evaluate the diagnostic value and clnical utility of serum calcitonin levels as a marker substance in bronchogenic cancer.