Tamiya Motohiro, Shiroyama Takayuki, Nishihara Takashi, Nishida Takuji, Hayama Manabu, Tanaka Ayako, Morishita Naoko, Suzuki Hidekazu, Okamoto Norio, Hirashima Tomonori
Department of Thoracic Malignancy, Osaka Prefectural Hospital Organization Osaka Prefectural Medical Center for Respiratory and Allergic Diseases, Habikino City, Osaka, Japan.
Asia Pac J Clin Oncol. 2017 Oct;13(5):e531-e533. doi: 10.1111/ajco.12643. Epub 2016 Dec 22.
Exon18 mutations are detected in 3.6% of epidermal growth factor receptor mutations. Exon 18 mutations as driver mutations have higher sensitivities in vitro to second-generation (G)-tyrosine kinase inhibitors (TKIs) than to first G- and third G-TKIs at clinically relevant doses. In clinical trial, first G-TKIs have moderate but insufficient efficacy, and afatinib was more active in uncommon epidermal growth factor receptor mutations. Here, we present a case of a woman who was initially prescribed erlotinib for lung adenocarcinoma with an exon18 mutation. She developed a leptomeningeal metastasis during treatment and was switched to afatinib. Subsequently, her symptoms improved and she is currently treated with maintenance afatinib therapy. This report suggests improved efficacy of afatinib compared to erlotinib for refractory leptomeningeal metastasis in exon18 mutation.
在表皮生长因子受体突变中，18号外显子突变的检出率为3.6%。作为驱动突变的18号外显子突变在体外对第二代（G）酪氨酸激酶抑制剂（TKIs）的敏感性高于在临床相关剂量下对第一代G和第三代G-TKIs的敏感性。在临床试验中，第一代G-TKIs疗效中等但不足，阿法替尼在罕见的表皮生长因子受体突变中活性更高。在此，我们报告一例女性患者，她最初因18号外显子突变的肺腺癌而被处方使用厄洛替尼。她在治疗期间发生了软脑膜转移，随后改用阿法替尼。随后，她的症状有所改善，目前正在接受阿法替尼维持治疗。本报告表明，与厄洛替尼相比，阿法替尼对18号外显子突变的难治性软脑膜转移疗效更佳。
