CNS response after erlotinib therapy in a patient with metastatic NSCLC with an EGFR mutation.

Background: A 73-year-old Asian man with a history of lipidemia, hypertension and myocardial infarction presented with dizziness, decreased appetite, weight loss, nonproductive cough and fatigue. His physical performance status was good, and physical examination was unremarkable except for lower-extremity pitting edema.

Investigations: Physical examination, brain MRI, CT scans of the chest, abdomen and pelvis, bone scan, CT scan-guided biopsy, hematoxylin and eosin staining, EGFR mutational analysis, and chest X-ray.