Hypercalcitonemia in bronchogenic cancer. Evidence for thyroid origin of the hormone.

Retrograde venous catheterization in a hypercalcitonemic patient with adenocarcinoma of the lung demonstrated that the thyroid gland was secreting a very large amount of hormone (14-fold higher than the peripheral level), while the venous drainage from the tumor deposits was similar in concentration to that of the periphery. Conceivably, the calcitonin is being elaborated in response to metastatic and humoral bone resorption or both. Radiotherapy resulted in a decrease in the calcitonin level. Further studies are needed to determine the diagnostic or prognostic implications of serum calcitonin in bronchogenic cancer.