There are several types of rhabdomyosarcoma that affect different areas of the body. Embryonal rhabdomyosarcoma most commonly develops in the head, neck, genitals, or urinary organs. This is the most common type of rhabdomyosarcoma, and it usually affects very young children. Alveolar rhabdomyosarcoma usually develops in the arms, legs, and abdomen, and it is most common among older children and teenagers. Another type of the cancer, called anaplastic rhabdomyosarcoma, rarely affects children, but it can develop in adults.