What is the recommended treatment for seizures due to brain metastasis?

Treatment for Seizures Due to Brain Metastasis

For patients with seizures due to brain metastasis, the recommended treatment is an anti-seizure medication, preferably a non-enzyme-inducing antiepileptic drug (NEIAED) such as levetiracetam (1000-3000 mg/day in divided doses), along with definitive treatment of the underlying brain metastasis. 1, 2

Initial Medical Management

Seizure Control

1. First-line medication choice:

   • Levetiracetam (Keppra) is the preferred agent due to:
     • Favorable side effect profile 1
     • Availability in both oral and parenteral formulations 3
     • No significant drug interactions with chemotherapy agents 4
     • Recommended dose: 1000-3000 mg/day in two divided doses 2

2. Alternative options (if levetiracetam is not tolerated):

   • Lacosamide
   • Lamotrigine
   • Gabapentin
   • Topiramate
   • Zonisamide 2, 3

3. Medications to avoid:

   • Enzyme-inducing antiepileptic drugs (EIAEDs) such as phenytoin, carbamazepine, and phenobarbital should be avoided due to:
     • Potential interactions with chemotherapy agents 4
     • Less favorable side effect profiles 1
   • Valproic acid requires caution due to potential hematologic toxicity, especially in patients receiving chemotherapy 3

Cerebral Edema Management

• Dexamethasone (4-16 mg/day) for symptomatic cerebral edema 1
• Taper to lowest effective dose as soon as clinically feasible
• Consider Pneumocystis jirovecii pneumonia prophylaxis for patients requiring >4 weeks of steroid treatment 1

Definitive Treatment of Brain Metastasis

The treatment of the underlying brain metastasis is crucial for long-term seizure control 5:

1. Surgical resection when appropriate (single or limited number of accessible lesions)
2. Radiation therapy options:
   • Stereotactic radiosurgery for limited number of metastases
   • Whole brain radiation therapy for multiple metastases
3. Systemic therapy based on primary tumor type and molecular characteristics

Monitoring and Follow-up

1. Seizure monitoring:

   • Document seizure frequency and characteristics
   • Assess medication compliance
   • Monitor for drug levels when appropriate

2. Neuroimaging:

   • New or worsening seizures often indicate tumor progression 2
   • Obtain MRI with contrast if seizure control deteriorates

3. Driving eligibility:

   • Patients should not drive until they have been seizure-free for at least 6 months 2
   • Adequate tumor control must be documented

Important Considerations

• Prophylactic anticonvulsants are not recommended for patients with brain metastases who have not experienced seizures 1
• Risk factors for seizures in patients with brain metastases include:
  • Temporal lobe location
  • Occipital lobe location
  • Multiple metastases (>2)
  • Bone involvement 5
• Factors associated with better seizure control after treatment:
  • Complete tumor resection
  • Postoperative chemotherapy
  • Absence of local recurrence 5

Treatment Algorithm

1. Acute seizure management:

   • Start levetiracetam 500-1000 mg twice daily
   • Add dexamethasone 4-16 mg/day if significant edema present

2. Definitive treatment planning:

   • Obtain MRI with contrast if not already done
   • Neurosurgical evaluation for possible resection
   • Radiation oncology consultation

3. Long-term management:

   • Continue anti-seizure medication
   • Gradually taper steroids as tolerated
   • Regular follow-up imaging to assess tumor control
   • Consider tapering anti-seizure medication only after prolonged seizure freedom (>1 year) and excellent tumor control

Most patients (93.8%) achieve good seizure control following appropriate treatment of brain metastases 5, highlighting the importance of addressing both the seizures and the underlying tumor.