This study evaluates hippocampus-sparing whole-brain radiotherapy with simultaneous integrated boost for patients with multiple brain metastases from non-small cell lung cancer. The primary endpoint is intracranial progression free survival, and secondary endpoints are verbal neurocognitive function, overall survival, adverse events according to CTCAE v4.03, and quality of life.

Inclusion Criteria:

• Pathologically proven diagnosis of primary non-small cell lung cancer
• 3 or more measurable brain metastasis ≥3 mm outside a 5-mm margin around either hippocampus on gadolinium contrast enhanced MRI within 14 days prior to registration
• KPS ≥70
• Age ≥55 years
• Informed consent prior to study entry

Exclusion Criteria:

• Patients with leptomeningeal metastases
• ≥3 organ sites of extracranial metastases (including lung-to-lung metastases) within 3 months
• Contraindication to MRI such as implanted metal devices or foreign bodies
• Prior radiation therapy (including SRS) to the brain