Recent advances in understanding and managing Paget's disease.

Paget's disease is a condition which continues to challenge and surprise. The dramatic fall in its incidence over the last three decades has been an enormous surprise, as is the capacity of a single infusion of the potent bisphosphonate, zoledronate, to produce biochemical remission in 90% of patients, remissions which usually persist for many years and raise the possibility of a cure in some patients. However, challenges in its management remain. The trials carried out in Paget's disease have almost always had biochemical indices as their primary endpoints. From these studies, we also know that bone pain is relieved, quality of life improved, bone histology normalised, and radiological lesions healed. Thus, disease progression is halted. Studies have not been powered to assess whether clinically important endpoints such as fracture and the need for joint replacement surgery are diminished, although these complications are well established as part of the natural history of the condition. Since disease progression is prevented by potent bisphosphonates, it is likely that disease complications will also be prevented. Zoledronate also reduces the frequency of follow-up needed and therefore provides a very cost-effective intervention in those who have symptomatic disease or are at risk of complications.