[Combined treatment of Paget's disease of bone with calcitonin and the diphosphonate EHDP].

To avoid the inhibitory effect of EHDP on bone mineralization, a variety of diphosphonates (Cl2MDP, APD) and a combination of EHDP with calcitonin have been used in the treatment of Paget's disease. In the present study, 13 patients received combined treatment with synthetic human calcitonin (HCT 0.5 mg s.c./day, 5--7 days per week) and EHDP (7.5 mg/kg, day, p.o.) for a mean duration of 6.1 months until disappearance of the symptoms. Results were compared with those obtained in a group of 10 patients treated with HCT alone. The clinical and biochemical effects were similar in both groups, although patients on the combined treatment were treated for a shorter period of time (6.1 vs 11.5 months, p less than 0.01). The desired clinical benefit was obtained within the first few months (4.9 +/- 0.9) in the group on the combined treatment, and within 8.7 +/- 2.4 months (p = 0.05) in the HCT group. Although the incidence of biochemical and scintigraphic relapse was higher than reported in the literature, no clinical recurrence has been observed up to 15 months after interruption of the combined treatment. This positive result casts doubt on the relevance of prolonged treatment of Paget's disease with HCT alone or in combination with EHDP, especially in elderly patients.