Other names: ASPS

Alveolar soft part sarcoma (ASPS) is a rare, slow growing, soft tissue sarcoma. It tends to occur more often in adolescents and young adults.

In people with alveolar soft part sarcoma, it has been observed that two chromosomes break and rejoin in a certain way, called an unbalanced translocation. The TFE3 gene breaks off from the X chromosome and attaches onto the ASPSCR1 gene on chromosome 17 to create a new "fusion" gene known as ASPSCR1-TFE3. The fusion gene then creates an abnormal protein that is thought to contribute to the development of ASPS.

In adults, ASPS is usually characterized by a painless mass in the thighs and buttocks, although it can occur in the trunk, arm or elsewhere. In children, the mass most often occurs in the head and neck, and most commonly the tongue and the eye socket. ASPS has the potential to metastasize to other areas of the body, including the lungs, brain and bone.

Treatment options include surgery and radiation. Tecentriq (atezolizumab) is the first FDA approved treatment for ASPS.

Drugs used to treat Alveolar Soft Part Sarcoma