PAX3-FOXO1 fusion

The PAX3-FOXO1 fusion is a genetic change often found in a type of cancer called alveolar rhabdomyosarcoma, a soft tissue cancer. It results from a swap of parts between two genes—PAX3 and FOXO1—that normally help regulate cell growth and development. When these parts fuse, they produce an abnormal gene that can lead to uncontrolled cell growth and tumor formation. This genetic marker helps doctors diagnosis and sometimes guide treatment decisions for this particular cancer.