Oligodendroglioma

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This blog is for informational purposes only and should not be taken as medical advice. Content is sourced from third parties, and we do not guarantee accuracy or accept any liability for its use. Always consult a qualified healthcare professional for medical guidance.

What is Oligodendroglioma?

Oligodendroglioma is a rare brain tumor originating from oligodendrocytes, glial cells that produce myelin in the central nervous system. It represents 2-5% of primary brain tumors and 5-18% of gliomas, typically affecting the cerebral hemispheres (frontal/temporal lobes). Graded as low (II, slow-growing) or anaplastic (III, aggressive), it’s characterized by 1p/19q codeletion (90% of cases) and IDH mutations, making it more responsive to therapy than other gliomas. In 2025, ~1,000 US cases annually, median age 40-50, slightly more in men, with seizures as common presentation.

Symptoms

Symptoms depend on tumor location and growth rate: seizures (70-90% of cases, often focal), headaches, cognitive changes (memory loss, personality alterations), weakness/paralysis (hemiparesis), sensory loss, visual field defects, and speech difficulties. Low-grade tumors cause gradual symptoms over years, while grade III progresses faster with increased intracranial pressure (nausea, vomiting). Symptoms mimic stroke or migraines.

Causes

Causes are unknown, but genetic alterations (IDH1/2 mutations in 80%, 1p/19q codeletion) drive growth. Risk factors include radiation exposure and hereditary syndromes (e.g., Li-Fraumeni), but no strong environmental/lifestyle links. In 2025, research shows epigenetic changes and tumor microenvironment promote progression from grade II to III.

Diagnosis

Diagnosis uses MRI (showing well-demarcated, calcified masses with minimal edema), CT for calcifications (50-90% of cases), and biopsy/resection for histopathology (fried-egg cells). Molecular testing confirms 1p/19q codeletion and IDH status. EEG assesses seizures, with PET/MR spectroscopy aiding grading. In 2025, AI enhances MRI for codeletion prediction.

Treatment

Treatment involves maximal safe resection (improving survival), followed by observation for low-grade or PCV chemotherapy (procarbazine, lomustine, vincristine) + radiation for grade III. Temozolomide is alternative for chemo. In 2025, vorasidenib (IDH inhibitor) extends progression-free survival by 11 months in IDH-mutant gliomas.

Future Outlook

In 2025, 5-year survival is 80% for grade II, 50% for grade III. Codeleted/IDH-mutant tumors have better prognosis (15-year survival 70%). IDH inhibitors like vorasidenib transform low-grade management. By 2030, vaccines and immunotherapy could raise survival to 90% for grade II, 70% for III.

Sources

The information for oligodendroglioma is drawn from Cleveland Clinic’s “Oligodendroglioma: Symptoms, Treatment & Prognosis” for symptoms and treatment; Mayo Clinic’s “Oligodendroglioma – Symptoms and causes” for causes; American Brain Tumor Association’s “Oligodendroglioma” for understanding; NCI’s “Oligodendroglioma Diagnosis and Treatment” for diagnosis; Cancer Research UK’s “Oligodendroglioma | Cancer Research UK” for research; National Brain Tumor Society’s “Oligodendroglioma | National Brain Tumor Society” for outlook; OncoDaily’s “Oligodendroglioma: Causes, Symptoms, Diagnosis, and Treatments” for diagnostic methods; UCLA Health’s “Oligodendroglioma – Neurosurgery | UCLA Health” for neurosurgery; Cancer Research UK’s “Oligodendroglioma” for subtypes; and OncoDaily’s “Oligodendroglioma: Latest Research and Treatments” for 2025 updates.