Most<unk> s are not associated with any known risk factors or identifiable cause. There are some exceptions: *Studies suggest that workers who are exposed to chlorophenols in wood preservatives and phenoxy herbicides may have an increased risk of developing<unk> s. An unusual percentage of patients with a rare blood vessel tumor, angiosarcoma of the liver, have been exposed to vinyl chloride in their work. This substance is used in the manufacture of certain plastics, notably PVC. *In the early 1900s, when scientists were just discovering the potential uses of radiation to treat disease, little was known about safe dosage levels and precise methods of delivery. At that time, radiation was used to treat a variety of noncancerous medical problems, including enlargement of the tonsils, adenoids, and thymus gland. Later, researchers found that high doses of radiation caused<unk> s in some patients. Because of this risk, radiation treatment for cancer is now planned to ensure that the maximum dosage of radiation is delivered to diseased<unk>  while surrounding healthy<unk>  is protected as much as possible. *Kaposi's sarcoma, a rare cancer of the cells that line blood vessels in the skin and mucus membranes, is caused by human herpesvirus 8. Kaposi's sarcoma often occurs in patients with acquired immune deficiency syndrome. Kaposi's sarcoma, however, has different characteristics from typical<unk> s and is treated differently. *In a very small fraction of cases, sarcoma may be related to a rare inherited genetic alteration of the p53 gene and is known as Li-Fraumeni syndrome. Certain other inherited diseases are associated with an increased risk of developing<unk> s. For example, people with neurofibromatosis type I (also called von Recklinghausen's disease, associated with alterations in the NF1 gene) are at an increased risk of developing<unk> s known as malignant peripheral nerve-sheath tumors. Patients with inherited retinoblastoma have alterations in the RB1 gene, a tumor-suppressor gene, and are likely to develop<unk> s as they mature into adulthood.
Soft-tissue sarcoma
Conidiobolomycosis
Sarcoma
Osteoblastoma
Angiosarcoma
Myosarcoma
Osteosarcoma
Hemangiosarcoma