The embryonal subtype of rhabdomyosarcoma is the most common variety of rhabdomyosarcoma, accounting for 50-70% of cases 1-2. It is typically seen in children below the age of 15.
Embryonal rhabdomyosarcomas are further divided into three sub types 1:
spindle cell rhabdomyosarcoma
- resembles leiomyosarcoma
- good prognosis
- botryoid rhabdomyosarcoma
- anaplastic rhabdomyosarcoma
Typically these tumors arise in the head and neck and genitourinary tract
- head and neck - 50%
- see rhabdomyosarcomas of the head and neck
- middle ear
- nasal cavity and paranasal spaces
- pelvis - 30%
- see rhabdomyosarcomas of the genitourinary tract
The features are non-specific (see radiographic features in the parent article: rhabdomyosarcoma), although, in general, embryonal rhabdomyosarcomas tend to be more homogeneous. When located in the extremities, they may cause bowing of long bones in children 1.