Inverse correlation between genetic aberrations and malignancy grade in ependymal tumors: a paradox?
H J Gilhuis1, J van der Laak, P Wesseling
1Department of Neurology, University Medical Center St Radboud, Nijmegen, The Netherlands. h.gilhuis@czzoneu.umcn.nl
Journal of Neuro-Oncology
|March 16, 2004
Summary
Myxopapillary ependymomas (mpEs) show distinct genetic differences from other ependymomas (Es) and anaplastic ependymomas (aEs). Extensive genomic alterations do not always indicate malignant behavior in these brain tumors.
Area of Science:
- Neuro-oncology
- Cancer Genomics
- Pathology
Background:
- Ependymal tumors encompass a spectrum of glial neoplasms with varying grades of malignancy.
- Understanding the genetic underpinnings of ependymal tumor subtypes is crucial for accurate diagnosis and prognosis.
Purpose of the Study:
- To investigate the correlation between genetic aberrations and malignancy grade in ependymal tumors at the ploidy level.
- To differentiate genetic profiles of myxopapillary ependymomas (mpEs), ependymomas (Es), and anaplastic ependymomas (aEs).
Main Methods:
- Image DNA cytometry and comparative genomic hybridization (CGH) were employed.
- Seven mpEs (WHO grade I), 28 Es (WHO grade II), and 18 aEs (WHO grade III) were analyzed.
- Ploidy status and CGH results were correlated with clinicopathological data.
Main Results:
- mpEs, predominantly spinal, showed high rates of aneuploidy/tetraploidy (6/7).
- Es (spinal/cerebral) and aEs (cerebral) had lower rates of aneuploidy/tetraploidy (6/28 and 4/18, respectively).
- CGH revealed the highest number of genetic aberrations in mpEs (avg. 16), fewer in Es (avg. 12), and the least in aEs (avg. 5).
- Aneuploidy did not consistently correlate with high genetic aberrations in Es and aEs.
Conclusions:
- Myxopapillary ependymomas exhibit a distinct genetic profile compared to other ependymoma subtypes.
- Extensive genomic alterations and aneuploidy in ependymal tumors do not solely predict malignant behavior.
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