botryoid rhabdomyosarcoma
Botryoid rhabdomyosarcoma, also known as sarcoma botryoides, is a type of embryonal rhabdomyosarcoma and accounts for 5-10% of all rhabdomyosarcomas .
Epidemiology
It tends to occur in pediatric population, often between birth and 15 years of age .
Pathology
Rhabdomyosarcomas generally have a nonspecific infiltrative appearance, the botryoid variant is unusual in that it manifests as a polypoid or "grape-like lesion" beneath the mucosa. It does not infiltrate the epithelium, and is described to have an intratubular appearance.
Distribution
They occur principally beneath a mucous membrane . Recognized sites of occurrence include:
- vagina
- urinary bladder
- cervix
- nasopharynx
- biliary tract - rhabdomyosarcoma of biliary tracts
With vaginal and urinary bladder locations being the most common.
Radiographic features
MRI
Lesions can be large. Signal characteristics are similar to rhabdomyosarcoma i.e :
- T1: low to intermediate
- T2: high
Grapelike intraluminal masses would favor a botryoides type.
History and etymology
Botryoid, derived from the Greek bótry(s) for grape, means resembling the form of grapes.
Differential diagnosis
Macroscopic differential diagnoses for the vaginal and urinary bladder locations based on the polypoid appearance include :
- yolk sac tumor
- tumoral cystits
For the pelvic/presacral region consider: