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.
Pathology
Embryonal rhabdomyosarcomas are further divided into three subtypes 1:
-
spindle cell rhabdomyosarcoma
- resembles leiomyosarcoma
- good prognosis
- botryoid rhabdomyosarcoma
- anaplastic rhabdomyosarcoma
Location
Typically these tumors arise in the head and neck and genitourinary tract
- head and neck (50%)
- see rhabdomyosarcomas of the head and neck
- orbit
- middle ear
- nasal cavity and paranasal spaces
- pelvis (30%)
- see rhabdomyosarcomas of the genitourinary tract
- prostate
- paratesticular
- retroperitoneum
- extremities
Radiographic features
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.