[Monotherapy with clodronate for tumor-induced hypercalcemia]

In the course of a phase II study 15 patients (nine women and six men; mean age 58 [45-69] years) received 300 mg clodronate daily during a total of 16 episodes of tumour-induced hypercalcaemia. Four women had breast cancer, four patients had plasmocytoma and four had bronchial carcinoma. One woman each had leiomyosarcoma or squamous cell carcinoma of the uterus or pancreatic carcinoma, respectively. No other calcium-lowering treatment, such as forced diuresis, glucocorticoids, calcitonin or mithramycin, was employed. As early as two days after onset of treatment the serum calcium concentration fell significantly from 3.63 +/- 0.42 to 2.80 +/- 0.40 mmol/l. After a mean interval of 4.3 days the hypercalcaemia had been eliminated during 15 of the 16 episodes. The treatment was not adequate in one patient with paraneoplastic hypercalcaemia. The results indicate that this medication is to be recommended as a standard treatment of tumour-induced hypercalcaemia; side effects are minimal.