What is Angiosarcoma?
Angiosarcoma is a highly invasive form of cancer. The tumors are malignant and grow rapidly arising from the cells that line the vessel walls of both the blood and lymphatic systems.
The endothelium layer is made up of endothelial cells that line all the blood vessels anf lymphatics. A tumor begins in this layer as a rapidly proliferating growth of immature cells that becomes cancerous and can quickly spread to other body systems.
Angiosarcoma is, like most cancers, uncontrolled cell replication. Its unique threat to the health of the individual, though, is in its relation to the circulatory system.
Hemangiosarcoma is when the tumor is filled with blood because the blood vessels grow directly into it. When a malignant condition is within the circulatory system it is very dangerous because the cancerous cells can spread the cancer easily to otherwise healthy systems. Angiosarcoma proves to be an aggressive, difficult to treat form of cancer because it directly affects the blood vessels. It also has a high recurrance rate.
Lymphangiosarcoma is an angiosarcoma in which the tumor cells originate from the endothelial cells of lymphatic vessels. The lymph system is responsible for the distribution of antibodies and disease-fighting agents throughout the body. Any time a cancer affects a system that is responsible for distributing chemicals throughout the body, such as blood or lymph, it can spread the mutated cancer cells throughout the body also.
Any organ of the body may develop angiosarcoma although the skin and soft tissue are the most common areas where it is found. The liver, spleen, hear, breast or bone can all be sites where it originates.
Cutaneous angiosarcoma, the most common form of angiosarcoma, is most often found in elderly persons. The tumors are primarily located on the head and neck.
Causes of most angiosarcomas are unknown. Though there are some risk factors that have been identified as leading to higher chance of developing a tumor.
Hemangiosarcomas are commonly associated with toxic exposure to thorium dioxide (Thorotrast), vinyl chloride, and arsenic. Stewart-Treves syndrome is a form of hemangiosarcoma due to lymphedema, usually following mastectomy and radiotherapy for breast cancer
Treatments like radiation and chemotherapy exposure to toxins like vinyl chloride have a higher risk to have angiosarcoma. People who have worked in the plastic industry were most likely exposed to vinyl chloride. It is used it during the processing stages of polyvinyl chloride. Cancerous tumors may still develop even if the exposure to these conditions or environmental toxins occurred has long as 30 years ago.
All these types of angiosarcomas are highly aggressive and destroy the body. Prognosis is usually poor and mortality rate high because of the high rate of local recurrence and because they are often misdiagnosed. Vascular malignant tumors do not respond well to chemotherapy and radiation which makes them very difficult to treat.
Research, around the world, is being done on P53, a tumor suppressor gene and its surrounding molecules. The research continues to be done in hope that one day new treatments may be found for this life threatening cancer.
