What causes tumors?

In reality, nobody knows what causes a sarcoma or a benign bone tumor. Because of the rarity of these tumors it has been difficult to perform extensive research on these types of tumors. Some tumors are related to genetic alterations that can actually be identified with special laboratory tests. There are also some rare genetic syndromes such as neurofibromatosis in which patients are predisposed to sarcomas. Radiation, a commonly employed treatment for certain cancers, can also cause bone sarcomas. Bone sarcomas can arise in the presence of Paget's disease. Certain chemicals have been loosely linked to sarcomas. There are predisposing factors for some carcinomas, such as cigarette smoking and lung cancer. There is a familial or genetic link for breast cancer as well as it being linked to the female sex (males have breast tissue also).