We report a case of multicentric massive osteolysis. A 52-year-old woman presented with a three-year history of progressive deformities of the hands. She had osteolytic lesions of the metacarpals and metatarsals, and resorption of the terminal phalanges. During follow-up over four years osteolysis spread to affect the ribs, clavicles, mandible, and long bones. There was no family history of any bone disorder and renal function was normal. Death resulted from resorption of the rib cage and post-mortem studies failed to reveal the cause of the osteolysis.