Diffuse glioneuronal tumor in Lynch syndrome: illustrative case

Area of Science:

• Neuro-oncology
• Genetics
• Cancer Biology

Background:

• Lynch syndrome (LS) is an inherited disorder linked to DNA mismatch repair defects.
• LS increases the risk of various cancers, including brain tumors like oligodendrogliomas and astrocytomas.
• This report details a unique case of LS with a glioneuronal tumor exhibiting both glial and neuronal differentiation.

Purpose of the Study:

• To report a rare case of a glioneuronal tumor in a patient with Lynch syndrome.
• To investigate the clinical behavior and prognosis of glioneuronal tumors associated with LS.
• To highlight the potential for aggressive tumor progression in this specific patient population.

Main Methods:

• Case presentation of a 34-year-old female with a frontal lobe mass.
• Surgical resection and histopathological examination of the tumor.
• Molecular testing for MSH2 mutation and germline testing for LS confirmation.
• Monitoring for tumor progression and assessment of proliferation markers (Ki-67).

Main Results:

• A low-grade-appearing glioneuronal tumor was diagnosed.
• The patient was confirmed to have Lynch syndrome due to an MSH2 mutation.
• Tumor progression occurred 12 months post-surgery, with a significant increase in Ki-67 proliferation index.
• Adjuvant therapy with temozolomide and radiation was initiated.

Conclusions:

• Glioneuronal tumors in the context of Lynch syndrome may exhibit a more aggressive clinical course.
• This case suggests a potentially worse prognosis for LS-associated glioneuronal tumors compared to typical cases.
• Further research is warranted to understand the implications of LS on brain tumor behavior.