Myxofibrosarcoma is a type of cancer that begins in the connective tissue. It tends to happen in the arms and legs.
Myxofibrosarcoma starts as a growth of cells that can grow into healthy body tissue. Myxofibrosarcoma might cause a lump under the skin that grows slowly. It often isn't painful. This cancer happens most often in older adults.
Myxofibrosarcoma is a type of soft tissue sarcoma. Soft tissue sarcomas are cancers that happen in the soft tissues that connect, support and surround other body structures.