Serum calcium in bronchial carcinoma: a population-based study.

Serum calcium (s-Ca) was measured in 245 patients with bronchial carcinoma. Mean s-Ca (+/- SD) was 2.52 +/- 0.14 mmol/l in the cancer patients, compared to 2.48 +/- 0.14 mmol/l in a control group (p less than 0.01). Sixty-one (25%) of the patients with bronchial carcinoma had hypercalcaemia (s-Ca greater than or equal to 2.60 mmol/l), compared to 16% of the controls. Squamous cell carcinoma was the histological type most often associated with hypercalcaemia. Patients with hypercalcaemia were not overrepresented among those with bone metastases. During follow-up another 32 patients developed hypercalcaemia. Altogether 93 patients (38%) became hypercalcaemic at some time in the course of the disease. In 20 patients s-Ca fell below 2.60 mmol/l after radiotherapy, after operation, or spontaneously. The survival time was significantly shorter for patients with s-Ca above 2.68 mmol/l on admission than for those with s-Ca below this value.