A pilot study to assess the efficacy of salmon calcitonin in the relief of neuropathic pain caused by extraskeletal metastases.

Although the pain-relieving activity of salmon calcitonin has been mainly demonstrated for painful bone metastases it has been postulated that the drug possesses a central analgesic activity which is independent of the opiate receptor system. Thus, 16 patients with neuropathic cancer pain due to radicular compression by extraskeletal metastases, and without the possibility of any specific anticancer treatment, entered the study. Of the 16, 11 were pretreated with opiate-type analgesics. Salmon calcitonin was applied once daily at a dose of 200 IU in 500 ml 0.9% NaCl infused over 1 h. The total duration of the treatment was 20 days. The pain-relieving effect was classified as very good, good, moderate and bad; in 10 patients it was described as bad, in 2 as moderate in 2 as good and in 2 as very good. The drug failed in 9/11 opiate-pretreated patients. It is suggested that salmon calcitonin pain-relieving activity might depend on the tumor type, previous pain-relieving drug intake and site of metastatic disease.