Oligodendroglioma of the Hippocampus: A Case Report and Systematic Review on Therapeutic Approaches of Oligodendroglioma After WHO 2021 Classification.

Background: Oligodendrogliomas are a molecularly distinct subtype of glioma according to the WHO 2021 tumor classification, defined as isocitrate dehydrogenase (IDH) mutations and 1p/19q co-deletion. This updated classification has changed the approach to glioma management by emphasizing the critical role of molecular diagnostics. This study explores current therapeutic strategies for adult oligodendrogliomas and contextualizes findings with a patient with a Grade 3 oligodendroglioma of the hippocampus. Methods: A systematic review was conducted, synthesizing evidence from 36 studies published between 2021 and 2024. The review focuses on surgical resection, PCV chemotherapy (procarbazine, lomustine, vincristine), and radiotherapy, with progression-free survival (PFS) and overall survival (OS) as primary outcomes. Moreover, a 45-year-old woman diagnosed with an IDH-mutant, 1p/19q-co-deleted Grade 3 oligodendroglioma is presented to illustrate clinical management. Results: The review highlights the significance of molecular profiling in personalizing treatment strategies. The findings highlight that maximal safe surgical resection combined with PCV chemotherapy and radiotherapy optimizes PFS and OS. However, our case underwent chemotherapy and radiotherapy after a multidisciplinary consultation, demonstrating favorable initial outcomes. These findings reaffirm the importance of integrating molecular insight into clinical decision-making. Conclusions: Advancements in molecular diagnostics have profoundly enhanced the personalization of therapy for oligodendrogliomas, yielding improved survival outcomes. Optimal management should entail a multidisciplinary approach incorporating surgery, chemotherapy, and radiotherapy, guided by molecular features. This study reinforces the necessity of molecular-driven strategies to improve survival and quality of care for patients with oligodendroglioma.