What is the recommended treatment for a patient with a high-grade glioma in the cerebellum?

Treatment of High-Grade Glioma in the Cerebellum

Maximal safe surgical resection followed by radiotherapy (60 Gy in 1.8-2 Gy fractions) plus concurrent and adjuvant temozolomide is the standard treatment approach for cerebellar high-grade gliomas in patients with good performance status. 1, 2, 3

Initial Management: Surgery First

All patients should be transferred to a specialized neurosurgical center for evaluation and treatment. 1

Surgical Approach

• Pursue maximal safe resection as the primary intervention, as extent of resection directly correlates with survival in high-grade gliomas 2, 4
• Obtain postoperative MRI within 24-72 hours to document extent of resection 1, 2
• If complete resection is not safely feasible due to proximity to critical cerebellar structures (brainstem, cranial nerve nuclei, cerebellar peduncles), perform subtotal resection or stereotactic biopsy to establish diagnosis 1
• Consider fluorescence-guided surgery with 5-aminolevulinic acid (5-ALA) to improve resection completeness 2

Critical caveat: The cerebellum's proximity to the brainstem and fourth ventricle makes preservation of neurological function paramount—do not sacrifice critical structures for marginal additional resection 1

Adjuvant Therapy Algorithm

For Patients with Good Performance Status (Karnofsky ≥70)

Standard regimen (Category 1 recommendation): 1, 3

1. Concurrent phase: Radiotherapy 60 Gy (1.8-2 Gy per fraction daily) PLUS temozolomide 75 mg/m² daily for up to 49 days
2. Adjuvant phase: Begin 4 weeks after completing radiotherapy—temozolomide 150-200 mg/m² on days 1-5 of each 28-day cycle for 6 cycles (12 cycles increasingly common) 1, 3

Initiate adjuvant treatment within one month of surgery 1

Molecular Testing Considerations

• Obtain MGMT promoter methylation status, IDH mutation status, and 1p/19q codeletion testing on surgical specimens 2, 5
• MGMT methylation predicts temozolomide benefit: methylated tumors show median survival of 23 months versus 13 months for unmethylated 5
• For 1p/19q codeleted anaplastic oligodendroglioma: consider PCV (procarbazine, lomustine, vincristine) chemotherapy as alternative to temozolomide 1

For Patients with Poor Performance Status (Karnofsky <70)

Choose ONE of the following: 1

• Hypofractionated radiotherapy (preferred over standard fractionation for elderly/poor PS patients)
• Temozolomide or PCV chemotherapy alone (Category 2B)
• Palliative/best supportive care

Essential Supportive Care Measures

Thromboembolism Prophylaxis

Implement venous thromboembolism prevention routinely, as glioma patients have high thrombotic risk 1

• Use low-molecular-weight heparin plus compression stockings perioperatively 1
• Continue prophylaxis during treatment, especially with concurrent temozolomide-radiotherapy

Pneumocystis Pneumonia Prophylaxis

Mandatory PCP prophylaxis during concurrent temozolomide-radiotherapy phase, regardless of lymphocyte count, continuing until lymphocyte recovery to ≤Grade 1 3

Corticosteroid Management

• Taper steroids as early as safely possible to minimize complications 2
• Monitor for steroid-related adverse effects (hyperglycemia, myopathy, psychiatric symptoms)

Surveillance Strategy

MRI brain with and without contrast every 3-4 months 2

• Be aware of pseudoprogression, which can occur 6-9 months post-radiotherapy and may mimic true progression 1
• Monitor neurological function, seizure control, and steroid requirements at each visit 2

Recurrent Disease Management

When progression occurs despite initial treatment:

• Enrollment in clinical trials is strongly preferred 1
• Consider surgical reresection if localized and surgically accessible 1
• Bevacizumab (antiangiogenic therapy) is FDA-approved for recurrent glioblastoma 1
• Alternative chemotherapy options: nitrosoureas (lomustine, carmustine), PCV, or oral etoposide 1
• Reirradiation may be feasible in select cases 1
• For poor performance status: transition to palliative/best supportive care 1

Key Prognostic Factors

Favorable prognostic indicators include: 1, 2, 5

• Younger age (<50 years)
• Good performance status (Karnofsky ≥70)
• Greater extent of resection
• MGMT promoter methylation
• IDH mutation (though rare in primary high-grade gliomas)
• 1p/19q codeletion (in oligodendroglial tumors)

Expected outcomes: Median survival for glioblastoma is approximately 15 months with standard treatment, extending to 23 months in MGMT-methylated tumors 5, 3