Definition
- Essential:
- Posterior fossa tumour with morphological and immunohistochemical features of ependymoma AND
- DNA methylation profile aligned with PFB ependymoma
- Desirable:
- Chromosomal instability and aneuploidy on genome-wide copy-number analysis
- Retained nuclear expression of H3 p.K28me3 (K27me3)
Numbers
- Mostly arise in adolescents and young adults, with a median age at presentation of 30 years.
Location
- Although they can occur throughout the 4th ventricle, tumours appear to arise more frequently from the ventricular floor.
Prognosis
- Better prognosis vs PFA
Molecular pathology
- High global levels of histone H3 K27-trimethylation (retention)
Gene | Gene name | Cytogenetic band | Function | Suppress | Promotes |
LATS2 | Large tumor suppressor kinase 2 | 13q12.11 | Tumor suppressor gene, involved in 13q loss | Suppression of growth; Invasion and metastasis; | Invasion and metastasis; Genome instability and mutations; Escaping cell death |
CDX2 | Caudal type homeobox 2 | 13q12.2 | Tumor suppressor gene, involved in 13q loss | ㅤ | Proliferative signaling |
BRCA2 | BRCA2 DNA repair associated | 13q13.1 | Tumor suppressor gene, involved in 13q loss | ㅤ | Genome instability and mutations; Escaping programmed cell death |
RB1 | RB transcriptional corepressor 1 | 13q14.2 | Tumor suppressor gene, involved in 13q loss | Suppression of growth; Escaping programmed cell death; Change of cellular energetics | Escaping immune response to cancer; Invasion and metastasis; Genome instability and mutations; Escaping cell death; Change of cellular energetics |
GPC5 | Glypican 5 | 13q31.3 | Tumor suppressor gene, involved in 13q loss | Suppression of growth; invasion and metastasis | ㅤ |
SOX21 | SRY-box transcription factor 21 | 13q32.1 | Tumor suppressor gene, involved in 13q loss | Suppression of growth | Proliferative signalling |
ERCC5 | ERCC excision repair 5, endonuclease | 13q33.1 | Tumor suppressor gene, involved in 13q loss | Genome instability and mutations; escaping programmed cell death | Genome instability and mutations; |
Made with Bullet