Calcitonin as a marker for bronchogenic cancer: a prospective study.

A prospective study was done of serum calcitonin (HCT) levels in 61 patients with bronchogenic cancer. Initially, 52% of patients had hypercalcitonemia. Hypercalcitonemia was not confined to patients with any particular histologic type. Seventy-eight percent of those with high calcitonin remained normocalcemic. There was no correlation between high calcitonin levels and osseous metastases. Selective thyroid venous sampling delineated two types of hypercalcitonemia: thyroidal and ectopic. To date, the ectopic type has been associated with the small cell bronchogenic carcinoma. High initial calcitonin levels decreased significantly in 75% of patients on antitumor therapy. In 13 evaluable patients calcitonin levels mirrored clinical status changes 67% of the time. Calcitonin may be a useful marker to assess the results of therapy in patients with bronchogenic cancer.