IDH2 R172

This case underscores that metachronous collision tumors can arise without radiotherapy, necessitating histopathological and molecular integration for accurate diagnosis. Long-term vigilance is critical for detecting sequential tumors, and shared microenvironments or genetic pathways may underlie tumorigenesis. Comprehensive profiling aids in clarifying pathogenesis and guiding management. https://thejns.org/doi/10.3171/CASE26149.

This case highlights the potential clinical relevance of IDH-directed therapy in IDH2-mutant cholangiocarcinoma and demonstrates feasibility in an immunosuppressed post-transplant setting. These findings are hypothesis-generating and support further evaluation of IDH inhibition in this population.

Compared to supratentorial tumors, non-R132H IDH1 mutations are significantly more frequent in infratentorial tumors. IDH2-mutant gliomas almost exclusively occur in adults and in supratentorial locations, with a significantly higher proportion in oligodendrogliomas than astrocytoma.

P1, N=24, Not yet recruiting, Megan Mantica

P3, N=57, Active, not recruiting, Servier | Trial primary completion date: Oct 2025 --> May 2026

IDH1 mutations were associated with global transcriptional repression and evidence of metabolic and epigenetic reprogramming. These results depict IDH-mutant prostate cancer as a subtype that can present with high tumor stage and grade, but is associated with favorable outcomes.

IDH2 and TP53 mutations are enriched in dedifferentiated CS and are significant, independent predictors of adverse survival, regardless of tumor grade. These findings support IDH2 mutation status as clinically meaningful prognostic biomarker that may allow risk stratification and clinical decision-making in CS patients.

P2, N=14, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: Feb 2026 --> Mar 2027

AML harbouring KMT2A-PTD frequently displays MR immunophenotypic abnormalities and is frequently associated with AML-MR type mutations. In addition, they have similar outcomes as compared with AML-MR.

He received adjuvant concurrent radiation and temozolomide...We present a case of IDH-mutant astrocytoma with a somewhat atypical molecular presentation, including a previously uncharacterized IDH2 mutation, retained ATRX expression, and lack of MGMT promoter hypermethylation. Though it has not been biochemically or functionally validated, tumor methylation profiling is supportive of this previously uncharacterized IDH2 variant as tumorigenic.

P2, N=15, Recruiting, Washington University School of Medicine | Trial completion date: Jun 2027 --> Feb 2029 | Trial primary completion date: May 2027 --> Jan 2028

Based on these data, the Idylla IDH1-2 mutation assay represents a fast and reliable alternative to detect IDH hotspot variants in solid tumors and hematological malignancies using either fixed tissue sections or DNA extracts. Particular attention, however, is needed for the interpretation of cases with cycle of quantification values of the internal controls over 35, for which a variant with low allelic frequency could be missed due to low DNA quantity or quality.