Epithelioid Hemangioendothelioma

What is epithelioid hemangioendothelioma?

Epithelioid hemangioendothelioma (EHE) is a rare cancer that forms from the cells lining your blood vessels (endothelial cells). Blood vessels, including veins, arteries and capillaries, are located throughout your body. Similarly, EHE can form anywhere in your body. Most often, EHE starts in your liver, lungs or bones. However, EHE can develop in other places, including your head, neck, thyroid, stomach, ovary, prostate, brain, spine, etc.

EHE may present as a single tumor, multiple tumors in a single organ or multiple organs. Often, by the time EHE is diagnosed, tumors have spread to more than one organ.

Is epithelioid hemangioendothelioma a sarcoma?

Yes. Sarcomas are tumors that may form in soft tissue, including the tissue in blood vessels. EHE begins in endothelial cells (cells that line blood vessels).

Is epithelioid hemangioendothelioma malignant?

EHE is a malignant (cancerous) tumor. Unlike benign tumors, EHE can grow out of control, spread to other parts of your body and damage healthy tissue.

However, EHE is complex because some tumors behave like more aggressive cancers and spread quickly. Other tumors grow slowly. Some tumors even shrink without treatment. Because these tumors behave so differently, it can be challenging to predict how serious a tumor is or how it will respond to treatment.

How common is EHE?

Epithelioid hemangioendothelioma is exceptionally rare. Less than 1 in 1 million people get this type of tumor. It’s more common in people aged 20 to 60, but children, teens and people older than 60 can also get EHE. EHE is slightly more common in people assigned female at birth, but researchers aren’t sure why.

What are the symptoms of epithelioid hemangioendothelioma?

Most people with EHE don’t notice any symptoms. When symptoms are present, the most common ones include pain, a mass that you can feel beneath your skin or unexplained weight loss.

Often, symptoms depend on where tumors are located. Signs and symptoms of EHE include:

• A mass that may or may not feel painful.
• Unexplained weight loss.
• Fever and fatigue.
• Pain in your abdomen (EHE in the liver).
• Trouble breathing (EHE in the lungs).
• Coughing or coughing up blood (EHE in the lungs).
• Enlarged fingertips or toes, called “clubbing” (EHE in the lungs).
• Bone pain, frequent fractures or broken bones (EHE in the bones).
• Trouble moving or walking (EHE in the spine).

What causes epithelioid hemangioendothelioma?

Malignant tumors, like EHE, form when a healthy cell transforms into a cancer cell that multiplies out of control.

Researchers have discovered that EHE is caused by a unique genetic mutation. It happens when two chromosomes join abnormally, causing one gene to join to another gene. These genes are WWTR1 (also known as TAZ) and CAMTA1. When WWTR1 joins with CAMTA1, it causes EHE.

Your provider may look for signs of abnormal chromosome attachments to diagnose EHE.

How is EHE diagnosed?

Since EHE doesn’t often cause symptoms, most people learn they have one or more tumors during an imaging procedure unrelated to EHE. Your provider will note where the tumor is located, its size, and whether it’s spread to other parts of your body (metastasized).

The most common procedures used to diagnose EHE include:

• CT scan: Your provider may order a CT scan to identify EHE tumors in your chest, abdomen and pelvis. A CT scan uses X-rays to scan your body and project images onto a computer screen that your provider sees. A CT scan allows your provider to see structures inside your body, like bones, organs, muscles and blood vessels.
• MRI: Your provider may order an MRI to check for EHE tumors in your liver and bones. An MRI uses magnets and radio waves to scan your body and project images onto a computer screen. A whole-body MRI that scans your body from head to toe is particularly useful in detecting bone tumors that have spread throughout your body.
• Core-needle biopsy: Once a tumor is seen by CT or MRI then a biopsy can confirm whether a tumor is EHE. During a core-needle biopsy, your provider uses a large hollow needle to remove tissue from the tumor. A lab specialist, called a pathologist, examines the tissue with a microscope to check for signs of cancer. A biopsy also helps your provider rule out other conditions that may be mistaken for EHE, like breast cancer.

Your provider may order other tests, like an ultrasound or a PET scan, to identify tumors and see if they’ve spread.

How is EHE treated?

EHE is so rare that there aren’t standard treatment guidelines. Instead, you’ll likely work with several specialists with experience in treating sarcomas. Your care team may include a cancer specialist (surgical oncologist), an imaging specialist (radiologist) and other specialists with expertise in treating a specific organ or body system (such as an orthopedic surgeon, liver transplant specialist, pathologist, etc.), among others.

The treatment you receive depends on various factors, including the tumor’s size, location, how many tumors you have and whether cancer has spread. Treatments may include:

• Watchful waiting: Your provider may monitor your cancer closely but avoid direct treatments if potential treatment side effects outweigh the benefits. A “wait and see” approach is often best when EHE is first detected if you’re not experiencing symptoms and you’re not a good candidate for surgery. Sometimes, these tumors shrink without treatment. In other instances, they grow slowly over many years. If your cancer worsens, your provider may recommend a different approach.
• Surgery: Surgery is the most common treatment for cases of EHE involving a single tumor. During the procedure, your provider will remove the tumor and some surrounding healthy tissue to ensure no cancer cells remain.
• Vascular embolization: Your provider may cut off the blood supply to your tumor, either as a standalone procedure or to shrink a tumor before surgery. This procedure is called embolization. Types of embolization your provider may recommend for EHE include transarterial chemoembolization (TACE) and radioembolization.
• Targeted therapy: Targeted therapy is the most commonly used treatment for advanced EHE. This kind of treatment uses drugs that prevent tumors from receiving the nutrients and oxygen they need to grow.
• Radiation therapy: Your provider may recommend radiation treatment following surgery to kill any remaining cancer cells. Radiation therapy may be the primary treatment if you’re not a good candidate for surgery. It can also help with symptom relief. Radiation therapy uses targeted energy beams to destroy cancer cells.
• Chemotherapy: Chemotherapy isn’t a common treatment for EHE. Still, your provider may recommend chemotherapy combined with other treatments if your cancer is more advanced. Chemotherapy uses drugs to destroy cancer cells. More research is needed to assess the potential uses of chemotherapy for EHE treatment.
• Organ transplant: Your provider may recommend an organ transplant (most commonly a liver transplant with EHE) if you have multiple tumors impacting a major organ.

Research on EHE is ongoing, and new treatments are constantly tested in clinical trials. Depending on the severity of your cancer, your provider may recommend you participate in a clinical trial.

How long can you live with epithelioid hemangioendothelioma?

Very little information exists about life expectancy with EHE. First, EHE is so rare that researchers are still collecting data about it. Also, the severity of EHE varies on a case-by-case basis. For some people, EHE progresses aggressively even with treatment. Other people never experience symptoms and live with tumors that never spread for several years. Some tumors shrink without treatment.

Ask your provider about your likely outcomes based on your diagnosis.

What questions should I ask my doctor?

• Where is my tumor located?
• Are there symptoms that will let me know if my tumor is growing?
• What factors affect my prognosis?
• Which treatments would you recommend?
• What are potential treatment side effects?
• What specialists will be involved in my care?
• How often will I need follow-up imaging or treatments?
• Would you suggest I get a second opinion?

A note from Cleveland Clinic

Receiving care from medical professionals you trust is always important, but it’s essential with an epithelioid hemangioendothelioma diagnosis. So much is still unknown about these rare sarcomas. Working with providers who have experience treating sarcomas and complex tumors can make all the difference in your care experience. Treatments may range from adopting a hands-off “wait and see” approach to testing new therapies in a clinical trial. Don’t hesitate to ask questions about how your treatment will likely unfold, including potential risks and benefits.