Several research groups are investigating cancer stem cells and their potential to cause tumors along with genes and proteins causative in different phenotypes. Radiotherapy for unrelated conditions may be a rare cause. * A small supernumerary marker chromosome or a giant rod chromosome is present in the tumor cells of low grade<unk>  including low grade central<unk>  and paraosteal<unk>  (see below Variants section), carry various potentially pro-cancerous genes, and are thought to contribute to the development of these<unk> . (See Small supernumerary marker chromosomes and giant rod chromosomes in<unk> s) * Familial cases where the deletion of chromosome 13q14 inactivates the retinoblastoma gene is associated with a high risk of<unk>  development. * Bone dysplasias, including Paget's disease of bone, fibrous dysplasia, enchondromatosis, and hereditary multiple exostoses, increase the risk of<unk> . * Li–Fraumeni syndrome (germline TP53 mutation) is a predisposing factor for<unk>  development. * Rothmund–Thomson syndrome (i.e. autosomal recessive association of congenital bone defects, hair and skin dysplasias, hypogonadism, and cataracts) is associated with increased risk of this disease. * Large doses of Sr-90, nicknamed bone seeker, increases the risk of bone cancer and leukemia in animals and is presumed to do so in people. There is no clear association between water fluoridation and cancer or deaths due to cancer, both for cancer in general and also specifically for bone cancer and<unk> . Series of research concluded that concentration of fluoride in water doesn't associate with<unk> . The beliefs regarding association of fluoride exposure and<unk>  stem from a study of US National Toxicology program in 1990, which showed uncertain evidence of association of fluoride and<unk>  in male rats. But there is still no solid evidence of cancer-causing tendency of fluoride in mice. Fluoridation of water has been practiced around the world to improve citizens' dental health. It is also deemed as major health success. Fluoride concentration levels in water supplies are regulated, such as United States Environmental Protection Agency regulates fluoride levels to not be greater than 4 milligrams per liter. Actually, water supplies already have natural occurring fluoride, but many communities chose to add more fluoride to the point that it can reduce tooth decay. Fluoride is also known for its ability to cause new bone formation. Yet, further research shows no<unk>  risks from fluoridated water in humans. Most of the research involved counting number of<unk>  patients cases in particular areas which has difference concentrations of fluoride in drinking water. The statistic analysis of the data shows no significant difference in occurrences of<unk>  cases in different fluoridated regions. Another important research involved collecting bone samples from<unk>  patients to measure fluoride concentration and compare them to bone samples of newly diagnosed malignant bone tumors. The result is that the median fluoride concentrations in bone samples of<unk>  patients and tumor controls are not significantly different. Not only fluoride concentration in bones, Fluoride exposures of<unk>  patients are also proven to be not significantly different from healthy people.
Osteosarcoma
Ewing's sarcoma
Osteoblastoma
Osteoma
Osteochondroma
Synovial sarcoma
Osteochondrosis
Bone cyst