What is an Alveolar Sarcoma?

Alveolar sarcoma is a very rare type of cancer. “Sarcoma” is a term used to refer to cancers that arise in the soft tissues and while sarcoma itself is relatively rare, alveolar sarcoma makes up around one percent of sarcomas. The condition is commonly seen in children and young adults. The prognosis for a patient can vary depending on the location of the cancer and its stage at the time of diagnosis. Because alveolar sarcoma can be difficult to spot in the early stages, sometimes it progresses very far before it is identified.

This type of sarcoma is named for the distinctive appearance of the tumor cells under the microscope. They look like the alveoli or air sacs found in the lungs, even though they are not actually filled with air. People with alveolar sarcoma most commonly develop primary tumors in the legs. As the tumors grow, new blood vessels form. These blood vessels can create a pathway for metastasis, with tumor cells traveling along the vessels to other parts of the body.

Alveolar sarcoma grows slowly. Patients may notice pain and soreness in the area where a tumor is developing, but the presence of a cancer may not become apparent until a palpable lump is felt. Doctors may not immediately think of alveolar sarcoma when patients present with telltale symptoms because of the rarity of the cancer, although people with certain genetic conditions are at increased risk of developing this cancer and thus their doctors may be alert to the warning signs. Diagnostic testing like biopsy and medical imaging can be used to diagnose alveolar sarcoma and stage the cancer.

The immediate treatment for this type of sarcoma is surgery to remove the tumor. In some cases, amputation of a limb may be necessary to completely remove the cancer and reduce the risk of spreading. Patients may be offered chemotherapy and radiation as adjuvant therapy, or primary therapies if it is not possible to surgically remove the tumors. Medical imaging will be used to follow up on the results of the treatment.

This malignant cancer has a tendency to recur. Because the cancer cells can distribute widely through the body and grow slowly, alveolar sarcoma may appear again years after initial diagnosis and treatment. Patients with a history of this cancer should be alert to warning signs of recurrence so that they can act quickly to receive treatment if it does recur.