CNS tumor with BCOR internal tandem duplication.

Area of Science:

• Neuro-oncology
• Pediatric oncology
• Molecular pathology

Background:

• Central nervous system (CNS) tumors represent a significant challenge in pediatric oncology.
• BCOR gene alterations are increasingly recognized in various tumor types, including CNS malignancies.
• Internal tandem duplications (ITDs) in genes like BCOR are emerging as critical oncogenic drivers.

Observation:

• An 18-month-old boy presented with symptoms of increased intracranial pressure, including torticollis and vomiting.
• Radiological imaging revealed a cerebellar hemispheric mass with extension to the cerebellopontine angle and foramen magnum.
• Histopathological analysis demonstrated a moderately cellular tumor with microcystic changes, myxoid features, and atypical Homer Wright rosettes.

Findings:

• Next-generation sequencing (NGS) identified an internal tandem duplication (ITD) in exon 15 of the BCOR gene.
• This specific genetic alteration, BCOR ITD, defines a recently proposed class of malignant CNS tumors.
• The molecular findings correlate with the observed aggressive histopathological features and clinical presentation.

Implications:

• The identification of BCOR ITD in CNS tumors provides a crucial diagnostic and potentially therapeutic target.
• This case highlights the importance of molecular profiling in diagnosing rare and aggressive pediatric brain tumors.
• Further research into BCOR-altered CNS tumors may lead to novel treatment strategies and improved patient outcomes.