Analgetic activity of calcitonin in patients with painful osteolytic metastases of breast cancer. Results of a controlled randomized study. Evaluation of salmon calcitonin treatment in bone metastases from breast cancer--a controlled trial.
The analgesic effect of salmon calcitonin was tested by a double-blind clinical randomized controlled trial in 40 female patients with painful osteolytic metastases. Twenty patients were administered (daily) 100 IU of salmon calcitonin subcutaneously over 28 days, while the other 20 were administered identical ampoules containing 2 ml of physiological solution over the same period of time. The basic treatment (chemotherapy, hormone therapy) was not changed during the trial, and had to be stabilized for a minimum of 3 months prior to the trial. The effect of calcitonin was monitored with respect to daily analgesic consumption, duration of pain, patient's functional capacity, patient's own assessment of pain, and assessment of efficacy by the investigator. Statistically significant differences were established in terms of reduced analgesic consumption, shorter duration of pain and the patient's subjective assessment of pain duration and intensity; the difference was not statistically significant with regard to patient's functional capacity. The objective assessment of the analgesic effect of calcitonin by the investigator showed the drug to be extremely useful in 3 patients and moderately useful in 11 patients; 3 instances of 'moderately useful' were observed in the placebo group. No changes were observed in serum calcium levels; there were likewise no skeleton changes as established by X-rays and bone scintiscans before and at the end of treatment. The trial has shown calcitonin to produce a pronounced analgesic effect in breast cancer patients with painful osteolytic metastases. Salmon calcitonin 100 MRCU/day or a saline placebo were given in daily injections for at least three months to 49 patients with bone metastases from breast cancer in a randomized double-blind trial. All patients were normocalcemic, and most patients had stable or regressing disease at start of trial. No improvement in general performance or bone pain was detected as measured by a visual analogue scale, the daily duration of pain or consumption of analgetic drugs. Calcitonin had no effect on disease progression as judged by bone scans and radiographs. Calcitonin therapy did not affect serum calcium, alkaline phosphatase, bone gla-protein, or the urinary excretion of calcium and hydroxyproline. Serum phosphate and magnesium decreased significantly during calcitonin treatment (p = 0.01, and 0.00005, respectively). It was concluded that salmon calcitonin in this dosage has no discernible effect on skeletal pain, general performance, bone metabolism or disease progression in patients with breast cancer metastatic to bone. A significant decrease in serum phosphate and magnesium probably indicated an effect of calcitonin on the renal excretion of these ions.
The limited evidence currently available does not support the use of calcitonin to control pain from bone metastases. Since the last version of this review, none of the new relevant studies have provided additional information on this treatment, in contrast to other therapeutic approaches that should be considered.