Atypical papillary glioneuronal tumor

Area of Science:

• Neuro-oncology
• Neurosurgery
• Pathology

Background:

• Papillary glioneuronal tumors (PGNTs) are rare primary brain tumors.
• While typically considered low-grade, some PGNTs exhibit atypical features.
• Understanding the behavior of atypical PGNTs is crucial for treatment planning.

Observation:

• A 34-year-old male presented with a 3-month history of headaches.
• MRI revealed a large cystic tumor in the right frontoparietal lobe.
• Pathological examination identified a papillary glioneuronal tumor with mitotic activity and a 15% Ki-67 index.

Findings:

• The patient underwent radical surgery followed by radiotherapy.
• Five years post-treatment, the patient remains symptom-free with no evidence of recurrence or residual tumor.
• This outcome suggests a potentially indolent course despite aggressive histological markers.

Implications:

• This case supports the existence of an atypical PGNT variant with high proliferative activity.
• Histological indicators of malignancy in PGNTs may not correlate with short-term unfavorable outcomes.
• Aggressive treatment modalities can be effective even in PGNTs with concerning pathological features.