A Case of Lung Adenocarcinoma Which Developed Carcinomatous Meningitis During Gefitinib Treatment, Improving After Switching to Erlotinib

Abstract

Background. Therapy for carcinomatous meningitis due to lung cancer has not been established. We experienced a case of lung adenocarcinoma that developed carcinomatous meningitis during gefitinib treatment and improved after changing the medication to erlotinib. Case. The patient was a 69-year-old male who underwent thoracoscopic right lower lobectomy for lung adenocarcinoma with an epidermal growth factor receptor (EGFR) mutation. The pathological staging was IA (pT1N0M0). Multiple bone metastases developed 19 months after surgery. Systemic chemotherapy was initiated, then stopped after only one course due to the patient's request. The patient complained of a headache 23 months after undergoing surgery and was diagnosed as having carcinomatous meningitis. He was prescribed gefitinib, and the headache and radiologic findings of multiple bone metastases improved. Four months after the initiation of gefitinib treatment; however, the headache and disorientation reappeared. The findings of contrast-enhanced magnetic resonance imaging (MRI) of the brain and a lumbar cerebrospinal fluid (CSF) examination confirmed the diagnosis of carcinomatous meningitis. Gefitinib was changed to erlotinib, and the patient's symptoms and MRI and CSF findings markedly improved. Conclusions. This case suggests that erlotinib is effective in cases of recurrence in the central nerve system in patients with lung cancer and EGFR mutations receiving gefitinib treatment.