Bisphosponates in multiple myeloma

Bone disease is a frequent manifestation of multiple myeloma, and results i n considerable morbidity. In this review we summarise the current theories as to the mechanism of bony destruction in this disease and discuss the int errelationships between the malignant plasma cells and those cells responsi ble for bone remodelling, i.e. the osteoclasts and osteoblasts. The bisphos phonates are a long established group of drugs known to have inhibitory eff ects on osteoclast activity, and in common use for osteoporosis and Paget's disease. Their role in myeloma is less clear. Several clinical studies, in cluding phase III randomised placebo controlled trials, have been reported in recent years. Although these have tended to show a benefit for bisphosph onate treatment, we have not yet identified the most appropriate use of the se agents. Two of the clinical trials have suggested that bisphosphonates m ay also have a beneficial effect on the underlying disease, a tantalising t heory which has been supported with some early laboratory data.