What is an Alveolar Soft Part Sarcoma?

An alveolar soft part sarcoma, or ASPS, is a cancerous tumor that develops in the body’s soft connective tissues. Muscles, tendons and joints are some of the types of soft tissue that can be affected by this type of cancer. Other soft tissues that may develop ASPS tumors include fat tissue, nerves and blood vessels. Most cases of this type of cancer occur in the legs, although it has developed less commonly in the neck and head.

Patients with alveolar soft part sarcoma often have a lump of soft tissue that is painless. Individuals with this condition may experience pain from muscle or nerve tissue that is compressed by a tumor. ASPS patients tend to limp while walking, and they can have other problems with their legs and feet. The range of motion generally becomes diminished in areas of soft tissue affected by this type of cancer.

Physicians often use one or more imaging tests to help them diagnose alveolar soft part sarcoma. X-rays may not provide detailed images of a soft tissue tumor, and some patients undergo tests such as a magnetic resonance imaging (MRI) test or a computerized tomography (CT) scan that are more likely to provide images that doctors can use. Blood tests, a thorough physical examination and a complete medical history are often used by physicians as they diagnose this form of cancer. A biopsy may be performed to remove part of a suspected tumor so that laboratory tests can look for cancer cells.

Cancer specialists typically evaluate the degree of metastasis of alveolar soft part sarcoma. Tumors that have metastasized have spread beyond their original location to other parts of a patient’s body. Some metastasized tumors can spread to the brain or lungs. Patients with localized tumors that have not spread to other parts of the body typically have a higher likelihood of successful treatment than those with metastasized tumors.

In many cases, doctors recommend surgical removal of an alveolar soft part sarcoma along with portions of surrounding tissue. Surgeons may be able to spare limbs affected by this form of cancer in some cases. Advanced forms of the disease are more likely to be treated with amputation of an affected limb. Cancer surgery may be followed with radiation therapy to kill any remaining cancer cells that were not removed during surgery.

Physicians and researchers are studying other forms of cancer treatment for patients with alveolar soft part sarcoma. Chemotherapy uses special drugs that typically target and kill cancer tumor cells. Biological therapies use substances that trigger the body’s immune system to fight more effectively against cancer tumors in many cases. Angiogenesis inhibitors are medications that usually block blood vessel development in tumors and restrict tumor growth.