Epithelioid Sarcoma โ Symptoms and Causes
Overview
Epithelioid sarcoma is a rare cancer that develops in the bodyโs soft tissues. It typically appears under the skin of the fingers, hands, forearms, knees, or lower legs.
This slow-growing cancer most commonly affects teenagers and young to middle-aged adults, though it can occur at any age.
As a type of soft tissue sarcoma, epithelioid sarcoma originates in the bodyโs connective tissues. Despite its slow growth pattern, this cancer has a tendency to recur after treatment, making follow-up care essential.
Symptoms
Epithelioid sarcoma often begins as a small, firm lump or group of lumps, usually on soft tissues under the skin. These lumps typically appear on the hands, fingers, forearms, or feet. The growth is usually slow and painless at first, which may delay diagnosis.
Common symptoms include:
- A painless lump that grows slowly
- Lumps that may break open and form an ulcer
- Swelling in nearby areas
- Limited movement in affected joints
In some cases, the first sign may be skin changes or a non-healing sore. As the disease progresses, patients might experience pain, numbness, or weakness in the affected area.
Proximal-type epithelioid sarcoma, which occurs in deeper tissues near the trunk of the body, may cause different symptoms. These tumors often grow faster and may cause more noticeable discomfort earlier.
Causes
The exact causes of epithelioid sarcoma remain unclear. Medical experts believe this rare soft tissue cancer develops due to genetic changes in cells.
The most significant genetic abnormality involves the loss of the INI1/SMARCB1 gene, which normally works as a tumor suppressor.
Several risk factors may contribute to developing epithelioid sarcoma:
- Previous Injuries: Some cases appear at sites of previous trauma, scars, or burns.
- Age: Most commonly affects young adults between 20-40 years old.
- Sex: Men are affected more frequently than women.
- Location: Often begins in soft tissues under the skin of the extremities, particularly fingers, hands, and forearms.
Unlike some other cancers, epithelioid sarcoma has not been strongly linked to environmental factors such as radiation exposure or chemical contact. Family history does not appear to play a major role in most cases, as this cancer rarely runs in families.
Risk Factors
Several factors may increase the chance of developing epithelioid sarcoma. Young adults between 20 and 40 years old face higher risks than other age groups. Men develop this cancer about twice as often as women.
Physical injury might play a role in some cases. Some patients report previous trauma to the area where the tumor later developed, though researchers havenโt established a clear cause-and-effect relationship.
People with certain genetic conditions may have higher risks. Those with mutations in the INI1/SMARCB1 gene face increased chances of developing this cancer. This gene normally helps suppress tumor formation.
Deep tissue injuries that heal poorly might also contribute to creating conditions where this cancer can develop.
Complications
Epithelioid sarcoma can lead to several serious problems if not treated promptly. The cancer often spreads (metastasizes) to other parts of the body.
Most commonly, it spreads to the lungs, nearby lymph nodes, and bone. About 40-50% of patients experience this spread during their illness.
Local recurrence is another major concern. Even after treatment, the cancer may return to the same area where it first appeared. The risk is higher when the tumor is removed without taking enough surrounding tissue.
As the tumor grows, it can invade nearby tissues and structures. This may cause pain, limited movement, or problems with nearby organs depending on where the cancer is located.
For tumors in the arms or legs, there may be swelling, numbness, or tingling if nerves are affected.
