Recovery from Carcinomatous Meningitis by Erlotinib

Treatment options include whole-brain irradiation, systemic chemotherapy, and intrathecal chemotherapy such as methotrexate [2]. Despite these measures, the prognosis is poor with a median survival of 2–3 months, and focal neurologic dysfunctions do not improve in most cases [1]. The benefit of EGFR tyrosine kinase inhibitors (TKIs) in the treatment of carcinomatous meningitis in patients with nonsmall-cell lung cancer (NSCLC) has recently attracted attention, although all publications were only case reports or case series [3–10]. Erlotinib is widely used in patients with advanced NSCLC and its clinical utility is now highly evaluated [5]; there are reports observing that erlotinib was effective in carcinomatous meningitis after the failure of gefitinib treatment [4, 6]. It is well known that the serum concentration of erlotinib is several times higher than that of gefitinib [6]. It is not likely that gefitinib, when administrated at 250 mg/day, can achieve adequate levels in the central nervous system (CNS); therefore, higher doses of gefitinib may be necessary. Very recently, 2 research groups determined the concentrations of erlotinib in plasma and the cerebrospinal fluid (CSF) and confirmed that there was a measurable penetration of erlotinib into the CSF [9, 10]. This observation suggests that erlotinib may be a therapeutic option for patients with carcinomatous meningitis developing during gefitinib treatment. As the patient had a rapid onset of symptoms, she received erlotinib rather than gefitinib in order to achieve adequate therapeutic concentrations within the CNS. In summary, we report on a rare case of NSCLC-related carcinomatous meningitis successfully treated with erlotinib.