Clinicopathologic and FISH-Based Evaluation of CDKN2A/B and EGFR in IDH Mutant Astrocytomas


Yildirim A. Y., Cetin S., Dolas I., Bilgic B., Unverengil G.

NOROPSIKIYATRI ARSIVI-ARCHIVES OF NEUROPSYCHIATRY, cilt.63, ss.431-435, 2026 (SCI-Expanded, Scopus, TRDizin)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 63
  • Basım Tarihi: 2026
  • Doi Numarası: 10.29399/npa.29351
  • Dergi Adı: NOROPSIKIYATRI ARSIVI-ARCHIVES OF NEUROPSYCHIATRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CINAHL, EMBASE, Psycinfo, TR DİZİN (ULAKBİM), Academic Search Ultimate (EBSCO), Middle East & Africa Database (ProQuest), Biomedical Reference Collection: Corporate Edition (EBSCO), Health Research Premium Collection (ProQuest)
  • Sayfa Sayıları: ss.431-435
  • İstanbul Üniversitesi Adresli: Evet

Özet

Introduction: Isocitrate dehydrogenase(IDH)-mutant astrocytomas represent a biologically distinct but clinically heterogeneous lineage. In the World Health Organization Central Nervous System 5 (WHO, CNS) classification, CDKN2A/B homozygous deletion is a grade 4-defining alteration, while Epidermal growth factor receptor (EGFR) amplification is primarily associated with IDH-wildtype glioblastomas. This study evaluates the frequency and prognostic significance of these alterations in strictly defined IDH-mutant astrocytomas. Methods: We analyzed 39 supratentorial IDH-mutant astrocytomas diagnosed between 2016 and 2020. CDKN2A/B deletion and EGFR amplification were assessed via routine fluorescence in situ hybridization (FISH) based testing and correlated with histologic parameters and clinical outcomes. Results: CDKN2A/B deletion was identified in 61.5% of cases; however, high-level homozygous deletion (>= 30% of nuclei) was present in only two cases. Epidermal growth factor receptor amplification was absent in all evaluable tumors. Neither WHO grade nor mitotic activity demonstrated a significant correlation with overall or disease-free survival. Notably, patients with high-level CDKN2A/B homozygous deletion remained alive without high-grade transformation at last follow-up. Conclusion: These findings highlight the limited prognostic value of morphology within this molecular lineage and underscore the necessity of integrating molecular biomarkers into diagnostic frameworks. Larger multicenter cohorts with extended follow-up are essential to clarify the long-term prognostic significance of specific CDKN2A/B alterations.