Combination treatment with bevacizumab plus erlotinib for meningeal carcinomatosis of afatinib-resistant EGFR mutated lung cancer without T790M mutation: a case report.

Meningeal carcinomatosis in lung cancer is known to have a very poor prognosis. Here we report a case in which bevacizumab plus erlotinib (BE) was effective against meningeal carcinomatosis from afatinib-resistant EGFR mutation-positive lung cancer. A 61-year-old man started afatinib, a 2nd generation molecular targeting drug, as first-line treatment for lung adenocarcinoma cT1bN0M1a stage IVA harboring EGFR exon19 deletion mutation. This treatment shrank the tumor and allowed sustained control of tumor growth. After 19 months from the start of treatment, head MRI revealed brain metastasis in the cerebellum and meningeal carcinomatosis with loss of appetite and slurred speech, in response to which whole-brain irradiation was performed. Head MRI 1 month after whole-brain irradiation showed no change in the disseminated lesions of the cerebellum. In Japan, osimertinib treatment after failure of EGFR-TKI treatments requires the T790M mutation in the tumor, blood or body fluid, so BE treatment was started as second-line treatment. Brain MRI showed improvement in cerebellar disseminated lesions 1 month after the start of BE treatment. BE treatment controlled intrapulmonary metastases, pleural disseminated lesions and meningeal carcinomatosis for 6 months. BE treatment as second-line treatment should be considered as an option for meningeal carcinomatosis of EGFR tyrosine kinase inhibitor (TKI) -resistant EGFR mutated lung cancer.