Bladder, ureter & renal pelvis
Other tumors
Neurofibroma
Author: Monika Roychowdhury, M.D.
Topic Completed: 1 December 2014
Minor changes: 3 December 2020
Copyright: 2003-2021, PathologyOutlines.com, Inc.
PubMed Search: Bladder [title] neurofibroma
Table of Contents
Definition / general | Epidemiology | Clinical features | Case reports | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Differential diagnosisCite this page: Roychowdhury M. Neurofibroma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/bladderneurofibroma.html. Accessed January 22nd, 2021.
Definition / general
- Benign mesenchymal tumor with nerve sheath differentiation
- Similar to counterparts elsewhere
Epidemiology
- Uncommon
- Classically occurs in young patients with a slight male predominance
- Presents early in life
- Strongly associated with neurofibromatosis type 1 (Cancer 1999;86:505, PDF)
Clinical features
- Plexiform neurofibromas are associated with neurofibromatosis; diffuse neurofibromas are not (Am J Surg Pathol 2008;32:907)
- May present with hematuria, irritative voiding symptoms and symptoms related to pelvic mass effect
Case reports
- 6 year old girl with neurofibromatosis-1, bladder plexiform neurofibroma and diffuse ganglioneuromatosis of bladder (Hum Pathol 2008;39:1708)
- 14 year old girl with pelvic plexiform neurofibroma involving urinary bladder (Pediatr Radiol 2008;38:916)
- 18 year old man with neurofibromatosis-1 (Radiographics 2004;24 Suppl 1:S237)
Gross description
- Polypoid or diffuse
Gross images
Images hosted on other servers:
Plexiform neurofibroma: M - mucosa is
surrounded by masses of nodules
Microscopic (histologic) description
- Histology is same as neurofibromas elsewhere
- Hypocellular proliferation of spindle cells with wavy bland nuclei
- Cells are arranged in loose fascicles intermixed with bundles of collagen
Microscopic (histologic) images
Images hosted on other servers:
Plexiform neurofibroma
Positive stains
Differential diagnosis
- Leiomyoma: has cigar-shaped nuclei, S100 negative, positive for smooth muscle actin and desmin
- Inflammatory myofibroblastic tumor: reactive spindle cells in inflammatory background
- Malignant peripheral nerve sheath tumor: has marked atypia and increased mitotic activity, may have necrosis
