Anaplastic ependymomas (WHO grade III ependymomas), in comparison to lower grade ependymomas, are characterized by a higher proliferative rate and a greater tendency to infiltrate surrounding brain or disseminate into cerebrospinal fluid causing drop metastases 1. The relevance of grading ependymomas is questionable, though, and molecular subgroups are likely to carry greater importance 4.
About 25% of ependymomas exhibit features of anaplasia with a high mitotic rate, microvascular proliferation, cellular pleomorphism, and intratumoral necrosis; these are considered WHO grade lll 2.
These tumors have a greater propensity to infiltrate surrounding brain or spinal cord parenchyma and have a higher proliferative rate.
Anaplastic ependymomas have appearances that are similar to grade II ependymomas, although they may have a greater predilection for invading adjacent parenchyma 3,4.
Treatment and prognosis
The treatment and prognosis of ependymomas are not clearly influenced by histological grading 4.
- 1. Armstrong TS, Vera-Bolanos E, Bekele BN et-al. Adult ependymal tumors: prognosis and the M. D. Anderson Cancer Center experience. Neuro-oncology. 2010;12 (8): 862-70. Neuro-oncology (full text) - doi:10.1093/neuonc/noq009 - Free text at pubmed - Pubmed citation
- 2.Haaga JR, Boll D. CT and MRI of the whole body. Mosby. (2009) ISBN:0323053750. Read it at Google Books - Find it at Amazon
- 3. Tominaga T, Kayama T, Kumabe T et-al. Anaplastic ependymomas: Clinical features and tumour suppressor gene p53 analysis. Acta neurochir. 1995;135 (3-4): 163-170. Acta neurochir (abstract) - doi:10.1007/BF02187763
- 4. Louis DN, Perry A, Reifenberger G et-al. The 2016 World Health Organization Classification of Tumors of the Central Nervous System: a summary. Acta Neuropathol. 2016;131 (6): 803-20. doi:10.1007/s00401-016-1545-1 - Pubmed citation