Embryonal rhabdomyosarcoma

Prostate
Other malignancies
Embryonal rhabdomyosarcoma

Authors: Kenneth Iczkowski, M.D. (see Authors page)

Revised: 18 November 2016, last major update November 2016

Copyright: (c) 2003-2016, PathologyOutlines.com, Inc.

PubMed search: prostatic embryonal rhabdomyosarcoma

Table of Contents

Cite this page: Embryonal rhabdomyosarcoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/prostateembryonalrhab.html. Accessed October 20th, 2018.

Definition / general

See Soft tissue topic

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

Image hosted on PathOut server, contributed by Kenneth Iczkowski, M.D.:

H&E

Images hosted on other servers:

Myogenin+

Bladder tumors

Differential diagnosis

Bladder rhabdomyosarcoma: may be difficult to distinguish if tumor is large