Granular cell astrocytomas show a high frequency of allelic loss but are not a genetically defined subset

Amilcar A. Castellano-Sanchez*, Hiroko Ohgaki, Hideako Yokoo, Bernd W. Scheithauer, Peter C. Burger, Ronald L. Hamilton, Sydney D. Finkelstein, Daniel J. Brat

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

34 Scopus citations

Abstract

Granular cell astrocytomas (GCA) are an uncommon morphologic variant of infiltrative glioma that contains a prominent population of atypical granular cells. As a rule, they are biologically aggressive compared to similar tumors without granular features. We sought to determine whether GCAs possess distinct genotypic alterations that might reflect their unique morphology or clinical behavior. Eleven GCAs occurring in 7 men and 4 women ranging in age from 46 to 75 years were investigated for genetic alterations of known significance in glial tumorigenesis, including LOH at 1p, 9p, 10q, 17p, and 19q, point mutations of TP53, deletions of p16(CDKN2A) and p14ARF, as well as EGFR amplifications. Tumors included had an infiltrative growth pattern and consisted of large, round cells packed with eosinophilic, PAS-positive granules that varied in quantity, ranging from 30 to 100% of tumor cells. Three tumors were of WHO grade II, one was grade III, and 7 were grade IV lesions. Overall, the tumors showed higher frequencies of LOH at 1p, 9p, 10q, 17p, and 19q than typical infiltrating astrocytomas of similar grades. Losses on 9p and 10q occurred in nearly all cases, including low grade lesions. TP53 mutations were identified in 2 grade IV GCAs, while combined p14ARF and p16(CDKN2A) homozygous deletions were noted in only one grade IV lesion. None showed EGFR amplification. We found no genetic alterations specific for GCA. Instead, it appears that granular cell change occurs across genetic subsets. The high frequency of allelic loss, especially on 9p and 10q, may confer aggressive growth potential and be related to their rapid clinical progression.

Original languageEnglish (US)
Pages (from-to)185-194
Number of pages10
JournalBrain Pathology
Volume13
Issue number2
DOIs
StatePublished - Apr 2003

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Neuroscience(all)
  • Clinical Neurology

Fingerprint Dive into the research topics of 'Granular cell astrocytomas show a high frequency of allelic loss but are not a genetically defined subset'. Together they form a unique fingerprint.

Cite this