Mediators of Bone Resorption and Hypercalcemia in Cancer

To the Editor: Garrett et al. (Aug. 27 issue)¹ reported that production of the bone-resorbing cytokine lymphotoxin is related to osteoclastic bone destruction and hypercalcemia in patients with myeloma. Their data indicate that lymphotoxin is the principal mediator of bone resorption, and they state that other mechanisms must also be involved in disturbing calcium homeostasis. The article did not mention the role of prostaglandins, which have been shown to be mediators of the bone resorption and hypercalcemia caused by certain sarcomas and solid tumors.² Prostaglandin E2 has been shown to be a potent stimulator of bone resorption.³ In rabbits with.