Afatinib improves survival in metastatic non–small-cell lung cancer driven by activating epidermal growth factor receptor mutations. QT interval prolongation is a possible side effect of targeted anticancer drugs, but this has not been reported before with afatinib. We report a case of metastatic pulmonary adenocarcinoma with epidermal growth factor receptor exon 19 deletion who was treated with first-line afatinib. The patient was started on afatinib with a total dose of 40 mg/day and experienced grade 3 (>500 ms) QT interval prolongation in the seventh week. Dose was interrupted and then reduced to 30 mg/day after the event repeated. QT prolongation occurred only once with the reduced dose and radiologic oligoprogression was detected. Local therapy was performed and afatinib was continued as 30 mg/day. To the best of our knowledge, this case marks the first QT interval prolongation associated with afatinib. It is prudent to perform a baseline cardiologic evaluation and electrocardiogram monitoring in non-small cell lung cancer patients treated with this drug.

阿法替尼通过激活表皮生长因子受体突变提高转移性​​非小细胞肺癌的生存率。QT 间期延长是靶向抗癌药物可能的副作用，但阿法替尼之前没有报道过这种情况。我们报告了一例接受一线阿法替尼治疗的表皮生长因子受体外显子 19 缺失的转移性肺腺癌病例。患者开始服用阿法替尼，总剂量为 40 毫克/天，并在第 7 周出现 3 级（>500 毫秒）QT 间期延长。剂量被中断，然后在重复事件后减至 30 毫克/天。QT 间期延长仅在剂量减少时发生一次，并且检测到放射学寡进展。进行了局部治疗，阿法替尼继续 30 毫克/天。据我们所知，该病例标志着与阿法替尼相关的首次 QT 间期延长。对接受该药物治疗的非小细胞肺癌患者进行基线心脏病学评估和心电图监测是谨慎的。