is a rare sarcoma that typically affects children. Only 20% of rhabdomyosarcomas occur in adults. There are only approximately 250 cases a year in the United States. It is a heterogeneous type of sarcoma, with several recognized subtypes, including Embryonal, Botryoid, Alveolar, and Pleomorphic as its principal types. Treatment for these sarcomas nearly always involves surgery, radiation, and chemotherapy. Cure rates are better for children than for adults, for unclear reasons. This is one form of sarcoma that can travel to lymph nodes, though it can also travel to lungs and other sites.
Sarcomas of Blood Vessels
comprise an uncommon group of sarcomas that appear to arise from the lining of blood vessels (endothelial cells) or their precursors. There are less aggressive (epithelioid hemangioendothelioma or EHE) and more aggressive forms (angiosarcoma) members of this family of sarcomas. Some blood vessel sarcomas can affect the lymphatic system (which carry fluid from soft tissue to lymph nodes). The vessels of the lymphatic system are lined with cells very similar to those found in blood vessels, and give rise to what is termed lymphangiosarcoma. Kaposi sarcoma is a form of blood vessel sarcoma that is caused by a virus, HHV-8 (also called KSHV), both in people with HIV disease, as well as a group of typically older persons who have intact immune systems. These tumors have a high risk of recurring where they start and can also travel to liver, bone, lung, and other sites.
Even rarer tumors can arise from the sensory organs that regulate blood flow to different parts of the body. These are termed glomus tumors, and can be painful. Surgery is usually the best way to treat this rare form of sarcoma. Another group of tumors that were once thought to arise from cells around blood vessels, hemangiopericytoma, is now termed solitary fibrous tumor/hemangiopericytoma, since the tumors all appear to be very similar in terms of their biology.
Solitary Fibrous Tumor
, which also encompasses the diagnosis hemangiopericytoma, is an uncommon tumor that is found in the chest cavity, orbit (which contain the eye), coverings of the brain (dura mater) or from the pelvis. There are less aggressive and more aggressive versions of this tumor, which can easily grow to a size of 6-10 inches or more in size before they cause symptoms of compression of other organs. The more aggressive form of this tumor is termed malignant solitary fibrous tumor, and is associated with metastatic disease to the lungs or to bone, among other sites.