Yamaguchi Fumihiro, Kato Eisuke, Wakabayashi Aya, Shikama Yusuke
Department of Respiratory Medicine, Showa University Fujigaoka Hospital, Yokohama, Kanagawa 227-8501, Japan.
Mol Clin Oncol. 2019 Aug;11(2):127-131. doi: 10.3892/mco.2019.1880. Epub 2019 Jun 13.
We herein report a case of squamous cell transformation combined with the epidermal growth factor receptor () mutation T790M associated with acquired resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs) in a 73-year-old male patient diagnosed with stage IVA lung adenocarcinoma. Gene alterations were analyzed by collecting and studying pleural effusion at the time of diagnosis. Examination revealed an exon 19 deletion in the gene. Following treatment with the second-generation EGFR-TKI afatinib, squamous cell carcinoma was identified by performing a re-biopsy of the recurrent site. Although the levels of cytokeratin 19 fragment, which is a tumor marker for the follow-up of squamous cell carcinoma, were increased at that point, the levels of carcinoembryonic antigen, a marker particularly associated with adenocarcinoma, remained within normal limits. The T790M mutation and the original exon 19 deletion were detected simultaneously. The patient received treatment with the third-generation EGFR-TKI osimertinib, achieving a good clinical response. These findings suggest that osimertinib is beneficial for lung adenocarcinoma patients with squamous cell transformation harboring the T790M mutation.
我们在此报告一例73岁男性IV A期肺腺癌患者，其鳞状细胞转化合并表皮生长因子受体（EGFR）T790M突变，该突变与对EGFR酪氨酸激酶抑制剂（EGFR-TKIs）获得性耐药相关。在诊断时通过收集和研究胸腔积液分析基因改变。检查发现EGFR基因第19外显子缺失。在用第二代EGFR-TKI阿法替尼治疗后，通过对复发部位进行再次活检确定为鳞状细胞癌。尽管此时作为鳞状细胞癌随访肿瘤标志物的细胞角蛋白19片段水平升高，但与腺癌特别相关的标志物癌胚抗原水平仍在正常范围内。同时检测到T790M突变和最初的第19外显子缺失。患者接受第三代EGFR-TKI奥希替尼治疗，取得了良好的临床反应。这些发现表明奥希替尼对伴有T790M突变的鳞状细胞转化的肺腺癌患者有益。
