Types of Rhabdomyosarcoma
There are 2 main types of rhabdomyosarcomas.
Embryonal rhabdomyosarcoma
Embryonal rhabdomyosarcoma (ERMS) is the most common type of rhabdomyosarcoma. It tends to occur in the head and neck area, bladder, vagina, and in or around the prostate and testes. ERMS usually affects infants and young children. The cells of ERMS look like the developing muscle cells of a 6- to 8-week-old fetus.
Two types of ERMS, botryoid and spindle cell rhabdomyosarcomas, tend to have a better prognosis (outlook) than the more common forms.
Alveolar rhabdomyosarcoma
Alveolar rhabdomyosarcoma (ARMS)occurs more often in large muscles of the trunk, arms, and legs and typically affects older children or teenagers. ARMS cells look like the normal muscle cells seen in a 10-week-old fetus.
Undifferentiated sarcoma
Some doctors group these uncommon cancers with the rhabdomyosarcomas. Although they are sarcomas, the cells don't have any features that help classify them further.
