Table of Contents
Definition / general | Essential features | Epidemiology | Clinical features | Prognostic factors | Treatment | Microscopic (histologic) description | Microscopic (histologic) images | Differential diagnosisCite this page: Embryonal rhabdomyosarcoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/prostateembryonalrhab.html. Accessed April 25th, 2018.
Definition / general
Essential features
- Small round cell to spindle cell tumor, variable cellularity
- Occurs in young patients and requires aggressive treatment
Epidemiology
- Most common prostatic malignancy in children / infants
Clinical features
- Firm, smooth enlargement of prostate
- Usually presents with stage 3 disease, sometimes with distant metastases
Prognostic factors
- Nodal metastases less common than in the head and neck counterpart of this tumor
- Prognosis has improved for children (Int J Cancer 2011;128:1232), but is still poor in adults (Int J Surg Pathol 2011;19:831, Diagn Pathol 2016;11:56)
- Better if tumor has a leiomyosarcoma-like appearance
Treatment
- Multiple agent chemotherapy, surgery and radiation
Microscopic (histologic) description
- Cellularity is greatest around blood vessels, with intervening myxoid and edematous areas and necrosis
- Tumor cells are primitive, round to spindled cells, with purely spindle cell variants being described (Int J Clin Exp Pathol 2014;7:5181)
- May have bizarre forms with abundant eosinophilic cytoplasm, variable cross striations
- Usually extraprostatic extension
- MyoD1 and Myogenin are the most sensitive and specific immunologic markers.
Microscopic (histologic) images
Differential diagnosis
- Bladder rhabdomyosarcoma: may be difficult to distinguish if tumor is large