Oligodendroglial ganglioglioma

Area of Science:

• Neuro-oncology
• Neuropathology
• Central Nervous System Tumors

Background:

• Gangliogliomas are rare CNS tumors typically featuring neoplastic ganglion cells and astrocytic components.
• Tumors predominantly composed of oligodendroglial tissue are exceptionally uncommon.
• This case presents a unique variant of ganglioglioma with a significant oligodendroglial component.

Observation:

• A 40-year-old woman presented with a well-demarcated cystic lesion in the right parietal lobe on MRI.
• The lesion showed minimal perifocal edema and no contrast enhancement of the cyst wall.
• Surgical resection was complete, and histological examination revealed a mixture of oligodendroglioma and dysplastic ganglionic cells.

Findings:

• Immunohistochemistry confirmed the oligodendroglial component expressing OLIG2 and NKX2.2, while negative for synaptophysin.
• Fluorescence in situ hybridization (FISH) detected loss of heterozygosity (LOH) of 1p/19q in the tumor.
• The tumor exhibited distinct histological features of both oligodendroglioma and dysplastic ganglionic elements.

Implications:

• This case expands the known spectrum of ganglioglioma histology.
• The presence of 1p/19q LOH suggests potential similarities to canonical oligodendrogliomas.
• Complete surgical resection appears to be an effective treatment strategy, with no recurrence observed in this case over 41 months post-operation.