CNS & pituitary tumors
Gliomas, glioneuronal tumors, and neuronal tumors
Ependymal tumors
Subependymoma
Author: Eman Abdelzaher, M.D., Ph.D.
Last author update: 1 August 2012
Last staff update: 18 April 2022
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Subependymoma [title]
Table of Contents
Definition / general | Epidemiology | Sites | Grading | Radiology description | Radiology images | Case reports | Treatment | Clinical images | Gross description | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Positive stainsCite this page: Abdelzaher E. Subependymoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cnstumorsubependymoma.html. Accessed March 30th, 2023.
Definition / general
- Benign slowly growing neoplasm typically attached to a ventricular wall
- Cell of origin unknown but resembles subependymal tissue
- Slow growing; 50% have symptoms (associated with larger size or specific locations, J Neurosurg 1978;49:689)
Epidemiology
- Affects middle aged to elderly adults, occasionally children
Sites
- Usually occurs in fourth ventricle (50 - 60% of cases) or lateral ventricles (30 - 40%), often as incidental finding at autopsy; also spinal cord, where it usually presents as intramedullary mass
Grading
- WHO grade I of IV; benign behavior
Radiology description
Neuroimaging:
- Nonenhancing sharply demarcated, nodular mass
- May be calcification or hemorrhage
- Intraspinal examples are eccentric and show minimal to moderate enhancement
Radiology images
Case #75
Intraventricular mass
Case reports
- 22 year old woman with spinal cord tumor (Br J Neurosurg 2004;18:548)
- 37 year old woman with spinal cord tumor (Neurol Med Chir (Tokyo) 2002;42:349)
- 48 year old woman with recurrent tumor of temporal horn (J Neurooncol 2003;62:315)
- 57 year old man with worsening headache with no focal neurologic signs (Case #75)
- Two cases of spinal cord tumor (Pathol Int 2003;53:169)
Treatment
- Excision is usually curative, occasionally radiation therapy
Clinical images
Images hosted on other servers:
Fourth ventricle
Gross description
- Well circumscribed, solid, gray white, sometimes calcified, protrudes into lateral ventricle or 4th ventricle
Microscopic (histologic) description
- Clusters of isomorphic nuclei embedded in a dense, fine, glial fibrillary background
- Mild nuclear pleomorphism, microcystic formations (especially in lateral ventricular tumors)
- May be occasional ependymal pseudorosettes, hemorrhage, calcification
- Rarely osseous metaplasia in childhood tumors (Neurol India 2003;51:98)
- No / rare mitoses
- No necrosis no / rare endothelial proliferation
- Classify as mixed ependymoma subependymoma if prominent ependymal component and grade based on ependymoma component
Microscopic (histologic) images
Contributed by Eman Abdelzaher, M.D., Ph.D., David Taylor, M.D., Nazila Azordegan, M.D. and Case #75
Bland nuclei, microcysts
Case #75
2x
4x
10x
Dot-like perinuclear (EMA)
40x (EMA)
Cytology description
- Microcystic formations, loose fibrillary networks and nuclear clusters with mild pleomorphism (Acta Cytol 2001;45:636)
Positive stains
- GFAP (100%), NSE (100%), NCAM (100%) (J Neurooncol 2005;74:1)
- Proliferation index: < 1% (Arch Pathol Lab Med 1999;123:306)
