Angiosarcoma (AS) is a class of sarcoma (soft tissue tumor) that affects the blood and lymphatic endothelial cells. This cancer is very malignant and aggressive in nature, occurring in almost all parts of the body.
It is uncommon among children, but affects both men and women equally. Cutaneous AS, which develops on the skin, especially on the face and scalp, is the most common type of AS. The diagnosis of this condition is difficult because of the lack of or misleading symptoms; this also makes the treatment complex.
Symptoms of Angiosarcoma
The symptoms of AS vary depending on the location and type of the disease. In many cases, the signs of occurrence may not be visible in the initial stages and manifest only when the tumor reaches an advanced stage or spreads to other parts of the body.
The general appearance might resemble some infection, lesion, staining of the body part, and presence of soft tissue mass, depending on the amount of soft tissues replaced. It also ranges from anemia, hepatic dysfunction, and bleeding, to pain due to compression of structures.
For cutaneous or skin AS, the symptoms exhibited are:
- Change of skin color
- Appearance of bruises
- Lesions or cut
For AS that affects the joints, difficulty or limitation in motion occurs. Pathologic fractures are seen in the AS of bone. Sometimes, soft lumps are also manifested.
Symptoms of breast AS are:
- General pain
- Thickened breast wall
- Variation in size and shape of the breast
- Change in the shape of nipple (it turns in or sinks into the breast or possesses an irregular shape)
- Rashes on or around nipple area
- Fluid discharge with blood stains from the nipple
- Skin dimpling
- Swelling in the armpit
Deep AS has no symptoms and remains unidentified till it spreads to other areas of the body. Radiation-induced AS is seen with a thickened skin and increased lesions, which may be painless in the area where radiation has been applied. The area may be violet in color.
Causes of Angiosarcoma
The core causes of most AS cases are unknown. Pre-existing conditions are believed to pave the way for the development of these tumors. Yet, there are few risk factors or agents that can increase the complications associated with the condition.
Some risk factors are:
Lymphedema: Chronic lymphedema is the most commonly identified risk factor in the skin as well as soft tissue AS. It is commonly seen in:
- Women who had undergone radical mastectomy and had Stewart–Treves syndrome for long.
- Legs of patients who had undergone inguinal lymphadenectomy as a treatment for the spread of Kettles syndrome.
- People with chronic lymphedema from birth, or due to infections or unknown causes.
Radiotherapy: AS that is induced by radiation occurs in the absence of chronic lymphedema. It arises in the regions where radiotherapy has been used, e.g., for treatment of cancer in the ovary, breast, and cervix endometrium, as well as Hodgkin disease. The risk of this type of sarcoma increases with the increase in the dosage and is found to appear nearly a decade after the occurrence of initial tumor.
Foreign Materials: The accidental or iatrogenic introduction of foreign materials into the body can increase the risk of developing AS. Some examples of such materials are steel, bone wax, plastic, surgical sponges, shrapnel, and Dacron.
Environmental Carcinogens: People are at an increased risk of AS when they are exposed to certain environmental carcinogens, which are:
- Sprays used against fungi and related species in vineyards.
- Fowler solution used to treat patients with psoriasis.
- Arsenic, which increases the chance of developing liver AS.
- Dioxin: an industrial toxin that is associated with the risk of soft tissue AS.
- Vinyl chloride, which is used in plastic industry for polymerization (causes liver as well as soft tissue AS)
Other factors: AIDS and pre-existing benign lesions are other related risk factors of the condition.
Genetic Causes and Inheritance of Angiosarcoma
Associations of AS with chromosomal abnormalities as well as genetic diseases that are inheritable were identified in recent studies. In this condition, there are two possibilities for frequent chromosomal abnormalities:
- Increase in the normal count of two in each of chromosomes 5, 8, and 20.
- The loss in count from chromosomes 7 to 22, and the male sex chromosome ‘Y.'
For example, in breast AS, gains in chromosome 8 are more common than any other genetic abnormalities.
Genetic diseases that are thought to have a link with AS are:
- Klippel–Trénaunay syndrome
- Von Hippel–Lindau disease
- Von Recklinghausen’s neurofibromatosis
Reports of a few isolated case studies also show that AS can happen among immediate relatives without any established cause. This underlines the chance of existence of a rare variant of AS which is inheritable or a probable, yet unknown exposure to an agent of the condition among the members of the family.