[Abstract] Massive bone lysis syndrome is a group of syndromes characterized by chronic progressive osteolysis destruction. [Alias] Progressive osteolysis; phantom bone; bone loss syndrome; angiomatous nevus with osteolysis. [Etiology] Unknown. Because the lesion area is rich in blood vessels and resembles a hemangioma, it is presumed that osteolysis is related to vasodilatation and compression. [Pathology] Osteolysis disappears and the bone tissue is replaced by fibrous tissue, in which there are more thin-walled and dilated blood vessels and blood sinus formation. [Clinical manifestations] Commonly seen in children and young and middle-aged adults. Most patients have a single focal lesion, but it can be multiple, mostly in the clavicle, scapula, humerus, ribs, ilium, and sit bones, etc. The jaws are more commonly involved in the mandible. The lesions are characterized by spontaneous and progressive bone resorption, localized pain and discomfort, and possible hemangioma of the surface skin. The lesion is characterized by spontaneous and progressive bone resorption with localized pain and discomfort. [Diagnosis] The diagnosis can be made based on clinical manifestations and X-ray examination. 1. Central jaw cancer: It also has toothache, loosening and falling off, and shows bone destruction on X-ray, but most of the patients are middle-aged and elderly, with severe pain, mostly in the molar area of mandible. 2. Osteolytic osteosarcoma: It is mostly seen in adolescents, with toothache, displacement and loosening, bone destruction on X-ray, but the pain is more intense, the lesion develops rapidly, progressive aggravation, local tissue expansion, easy bleeding, worm-like destruction of jaw bone on X-ray, and periosteal reaction. [Treatment] Radiation therapy is effective, or surgery is possible. [Prognosis] It is self-limiting, with a good prognosis and does not affect life expectancy.