Angiosarcoma

What is Angiosarcoma?

Angiosarcoma, or AS for short, is a very rare type of cancer that forms in the inner lining of blood vessels or lymph vessels. It makes up only 1% of all soft tissue sarcomas, which are themselves a rare type of cancer. ‘High-grade’ describes the aggressive nature of this cancer. It can show up anywhere in the body but it’s usually found on the skin of elderly white men, or on the chest wall in individuals who’ve had radiation therapy for breast cancer.

Treatment for angiosarcoma is very difficult, and the outcome tends to be poor if the cancer is found after it has spread to other parts of the body. The best way to care for someone with AS is with a team of medical professionals who are experienced in treating this type of tumor. Just like other soft tissue sarcomas, surgery to remove the tumor along with some of the surrounding healthy tissue generally provides the best survival rates.

Combining radiation therapy with a drug called paclitaxel once a week, has shown to be effective for angiosarcoma in the skin. Also, two drugs, Doxorubicin and paclitaxel, are suggested for treating advanced or metastatic angiosarcoma. There are early signs that therapies targeting a substance called vascular endothelial growth factor (VEGF), which promotes the growth of new blood vessels and may play a role in the development of AS, could be promising. However, this approach hasn’t been proven effective in a large-scale clinical trial yet.

What Causes Angiosarcoma?

AS, or angiosarcoma, is mainly a type of cancer that occurs on its own, but it can also develop from a harmless blood vessel-related growth. This cancer is often seen in those who have survived breast cancer and went through radiation therapy to the chest area. However, AS can develop in any body part that was previously exposed to radiation.

Additionally, there’s a condition known as Stewart-Treves syndrome, where AS occurs due to chronic lymphedema, a condition of persistent swelling often linked with cancer and its treatments, or an infection like filariasis, often referred to as Milroy’s disease.

There are some reports that point to a connection between AS and changes in the DNA repair genes BRCA1 and BRCA2. Certain familial syndromes like neurofibromatosis, Maffucci syndrome, or Klippel-Trenaunay syndrome are also linked to AS. Lastly, specific chemicals such as vinyl chloride, thorium dioxide, arsenic, radium, and anabolic steroids are also associated with the development of AS.

Risk Factors and Frequency for Angiosarcoma

Soft tissue sarcomas (STS), which angiosarcomas (AS) are a part of, make up 1% of all cancer types. Angiosarcomas specifically account for up to 2% of all STS and between 4-5% of all skin-related STS. This type of cancer can affect just about anyone, but it’s more commonly found in older white men. It can appear anywhere in the body, however it’s more frequently seen in the head and neck area, especially on the scalp. While rare, this type of cancer can also occur in major blood vessels and the heart because it originates in the endothelium, the lining of our blood vessels.

Signs and Symptoms of Angiosarcoma

When a person presents with a lump that could potentially be cancerous, it is essential for healthcare professionals to conduct a detailed health history and physical check-up. If the person has a history of receiving radiation therapy, particularly if this occurred over a decade ago, this might increase the suspicion for soft tissue sarcomas, including angiosarcoma. Even though a family history of angiosarcoma is extremely rare, it’s worth checking for each case. The patient’s history should also include potential exposure to certain chemicals and any past surgical procedures that involved removing lymph nodes. Factors like chronic swelling of a limb (lymphedema) and previous parasitic infections can assist in establishing a diagnosis.

In a physical exam, medical practitioners should check for signs like lymphedema, changes in fingernails or hair (which could indicate exposure to harmful chemicals), signs of radiation burns, and any scars from past surgeries or radiation therapy. Angiosarcoma that affects the skin can look like a bruise or a raised purple-red bump. As the tumor grows, its surface may become sore, protrude visibly, bleed easily, and exhibit signs of tissue invasion. It typically spreads to multiple sites. Angiosarcoma affecting internal organs generally shows up as a growing mass which compresses neighboring structures causing obstructive symptoms. This type of cancer usually spreads via the blood to other sites including the lungs, bones and other soft tissues.

Testing for Angiosarcoma

In cases of angiosarcoma (AS), a type of cancer, typical medical tests may not show anything unusual. This is unless the tumor or lump is large enough to exert pressure on essential organs, causing them to malfunction. For instance, if the tumor is pressing on the ureter (a tube that carries urine from the kidney to the bladder), it could lead to kidney failure. Sometimes, when the disease has advanced, the tests can show slight abnormalities like long-term anemia or an elevated sedimentation rate, which measures inflammation in the body. But, none of these lab tests can specifically identify angiosarcoma.

To make a proper diagnosis, more advanced imaging tests like CT scans (3D x-rays), MRI (uses a magnetic field to show clear images of the body’s internal structures), or PET scans (displays how organs and tissues are functioning) are needed. These tests help doctors see the tumor’s exact location and how much it has spread in the body. In some special locations like the heart, a detailed 3D ultrasound (a test that uses sound waves to create a moving picture of the heart) may also be necessary.

Doctors also need to check if the cancer has spread, or metastasized, to other parts of the body, including the brain and the lymph nodes (small glands that filter lymph fluid, part of the body’s immune system). This initial check-up includes an MRI of the brain and CT scans of the chest, abdomen, and pelvis. Angiosarcoma patients should regularly get these CT scans to monitor the disease. Whether an iodine-based dye, which helps to see the images more clearly, should be used during these scans depends on the patient’s health condition.

The final diagnosis is made using a biopsy, where a small sample of tissue is taken from the body and examined under a microscope. This process, called histopathology, allows doctors to study the cells more closely and confirm if it’s angiosarcoma.

Treatment Options for Angiosarcoma

Patients diagnosed with STS, a group of rare cancers that occur in the bones and soft tissues, can also benefit from a combined team approach for angiosarcoma (AS), a type of STS. This disease can be present in an early stage (non-metastatic) or a later stage (metastatic), and the treatment varies accordingly.

In the early stage, the best treatment is a surgery that removes all of the tumor and has no cancer cells visible at the edges under a microscope (R0 resection). The nature of AS makes it prone to spreading, so the surgeon will try to remove a wider margin of tissue as a precaution. Because AS is a potentially deadly type of cancer, radiation therapy (RT) is usually recommended during the surgery. While it hasn’t been proven that chemotherapy after surgery is effective, it might be used before surgery in cases where the tumor size is large. For some patients, a drug called paclitaxel might be added to RT to improve its effectiveness. Other studies have shown positive results using proton beam therapy (a type of RT) and chemotherapy together for heart AS.

When AS is detected at a later stage and has spread to other parts of the body (metastatic disease), the patient is treated with chemotherapy. Several treatments are being studied for metastatic AS, such as toxic anti-cancer drugs (cytotoxic chemotherapy), targeted therapies, and immune checkpoint inhibitors, which can boost the body’s immune system to fight cancer.

Chemotherapy usually starts with anthracycline-based drugs. If these drugs aren’t effective, then paclitaxel may be used due to its promising results. Apart from anthracyclines and paclitaxel, other chemotherapy drugs may be helpful but they are usually not the first choices.

Another option being analyzed is the use of drugs that block the action of VEGF, a protein that contributes to cancer growth. Bevacizumab, for example, was considered for AS treatment but didn’t show any advantage in a clinical trial. Drugs known as Tyrosine Kinase inhibitors (Sorafenib, Pazopanib, Axitinib, and Regorafenib), which also aim to interrupt cancer growth, didn’t result in any significant improvement in AS patients. However, we can’t disregard their usefulness entirely as they showed some activity in these patients.

Lastly, immune checkpoint inhibitors are showing potential in treating AS and their effectiveness is being tested in ongoing clinical trials.

What else can Angiosarcoma be?

Angiosarcoma (AS) is one of over 70 different types of soft tissue sarcomas (STS). It’s included in the category of vascular tumors. These vascular tumors form a major part of the list that doctors look at when trying to diagnose Angiosarcoma. There are several types of these vascular tumors:

• Reactive and benign vascular tumors
• Capillary hemangiomas
• Juvenile hemangioma (strawberry naevus)
• Cherry angioma (Campbell de Morgan spot)
• Pyogenic granuloma
• Cavernous hemangiomas
• Epithelioid hemangioma
• Vascular ectasis (naevus flammus, spider naevus)
• Angiomatosis
• Postradiation atypical vascular lesion
• Intermediate grade vascular tumors
• Kaposi’s sarcoma
• Epithelioid haemangioendothelioma
• Malignant vascular tumors
• Angiosarcoma
• Tumors of perivascular cells
• Haemangiopericytoma (solitary fibrous tumor)

It’s important for physicians to carefully consider all these possibilities when diagnosing Angiosarcoma.

What to expect with Angiosarcoma

Angiosarcoma, or AS, has a rather low survival rate, with about 35% of patients living beyond five years. This five-year survival rate even applies to patients with localized disease that doctors can remove entirely, with over half of these patients surviving past five years (though the average survival time, or ‘median survival’, is around seven months).

Unfortunately, certain factors can predict a poorer outcome. Older age, disease that has spread to other parts of the body (metastatic disease) at the time of discovery, and poor overall health can indicate a less favorable prognosis. The prognosis can be particularly poor if the AS occurs in unusual locations such as the liver and heart or if it is induced by radiation therapy.

Moreover, larger tumors, particularly those over 5 cm, have been linked to worse outcomes in some studies.

Preventing Angiosarcoma

It’s important for both patients and doctors to recognize that this disease is both rare and aggressive, and that it requires careful coordination across various medical disciplines. While there have not been any large-scale studies specifically focusing on this disease, past data has shown that controlling the disease locally (in the specific area where it’s occurring) can help improve survival rates. This usually involves surgery coupled with radiation therapy during the healing process.

However, even with these measures, there’s a high chance the disease may return. Therefore, it’s essential for patients to have regular check-ups and imaging scans to monitor any changes or signs of the disease returning.