|
|
Bisphosphonates and Calcitonin
Severe bone pain is a frequent complication of bone metastases. For example,172 reported that 65 percent of patients with bone metastases from breast cancer experience bone pain. Bone pain is probably caused by osteoclast-induced bone resorption by the tumor, which may also result in osteoporosis, hypercalcemia, microfractures, or pathologic fractures.172 Bisphosphonates (e.g., etidronate, pamidronate) are analogues of endogenous pyrophosphates, which inhibit bone resorption in viva.157 Pamidronate and etidronate are currently available for the management of hypercalcemia associated with malignancy. Anecdotal reports and early clinical trials have reported relief of bone pain or decreased analgesic use after the initiation of a bisphosphonate.116; 133 Other researchers have described similar findings with bisphosphonates that are not available in the United States.28; 475 Smith (1989), however, reported no difference in symptomatic relief or analgesic requirements in 57 patients with advanced hormone-refractory prostate cancer treated with etidronate or placebo.428
Calcitonin is also a potent inhibitor of osteoclast-induced bone resorption and, like the bisphosphonates, is used in the management of hypercalcemia of malignancy. At least one double-blind, randomized trial comparing salmon calcitonin to placebo demonstrated that 100 IU/day subcutaneously resulted in reduced analgesic consumption, shorter duration of pain, and subjective improvement.400
Although these agents that inhibit bone resorption appear to be beneficial in some patients with painful bone metastases, other patients have failed to respond. Additional studies are warranted to define criteria that may predict a clinical response to these drugs and to define further their optimal use in this setting.
Go to the Adjuvant Drugs Menu
Go to the Pharmacologic Management of Pain in HIV/AIDS Menu
Go to the Pain & HIV/AIDS Menu
Go to the HIVpositive.us Main Menu
74