Division of Medical Oncology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Clinical Molecular Pathology Laboratory, Department of Clinical Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
BMC Cancer. 2019 Jul 17;19(1):701. doi: 10.1186/s12885-019-5913-9.
Uncommon epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) is a rare subset of NSCLC. The aim of this study was to investigate the prevalence, characteristics, and clinical outcomes of metastatic NSCLC harboring uncommon EGFR mutation at Thailand's largest national tertiary hospital. The secondary objective was to compare treatment efficacy between EGFR-tyrosine kinase inhibitor (EGFR-TKI) and chemotherapy.
This retrospective chart review included patients that were tested for EGFR-mutation NSCLC during 2014-2018. Patient demographic and clinical data, treatment data, and outcome data were collected and analyzed.
Of the 681 patients that were evaluated for EGFR mutation, 317 (47.0%) had EGFR-mutant NSCLC, and 28 (8.8%) of those harbored uncommon EGFR mutations. The median follow-up was 19.1 months. History of tobacco use was reported in 50% of patients. The most common single mutation among uncommon EGFR was exon 20 insertion (n = 6), followed by L861Q (n = 5) and G719X (n = 4). Thirteen (46%) patients had compound mutations. One hundred percent of male patients with G719X mutation were smokers. Sixteen of 28 patients were treated with EGFR-TKI. Most received first-generation EGFR-TKI, and 29% were treated with chemotherapy alone. The objective response rate was 37.5% in the EGFR-TKI group. Median progression-free survival (PFS) in the EGFR-TKI group was 10.2 months. Median PFS among the 8 patients in the chemotherapy group that received first-line platinum doublet was 6.5 months. Three-year overall survival (OS) among 28 patients was 34%. Three-year OS was significantly better in patients treated with EGFR-TKI.
Uncommon EGFR mutations was detected in 8.8% of EGFR-mutant NSCLC. Exon 20 insertion was the most common mutation, and 50% of patients had history of tobacco use. First- or second-generation EGFR-TKI demonstrated greater OS benefit than platinum-doublet chemotherapy among patients harboring uncommon EGFR-mutant NSCLC. Survival outcomes were comparable to those reported from previous large cohort studies.
罕见的表皮生长因子受体（EGFR）突变非小细胞肺癌（NSCLC）是 NSCLC 的一个罕见亚群。本研究的目的是在泰国最大的国立三级医院调查罕见 EGFR 突变转移性 NSCLC 的患病率、特征和临床结局。次要目的是比较 EGFR 酪氨酸激酶抑制剂（EGFR-TKI）和化疗的治疗效果。
本回顾性图表回顾性分析包括 2014 年至 2018 年间接受 EGFR 突变 NSCLC 检测的患者。收集并分析了患者的人口统计学和临床数据、治疗数据和结局数据。
在 681 例接受 EGFR 突变评估的患者中，有 317 例（47.0%）患有 EGFR 突变 NSCLC，其中 28 例（8.8%）存在罕见 EGFR 突变。中位随访时间为 19.1 个月。50%的患者有吸烟史。罕见 EGFR 中最常见的单一突变是外显子 20 插入（n=6），其次是 L861Q（n=5）和 G719X（n=4）。13 例（46%）患者存在复合突变。G719X 突变的男性患者 100%均为吸烟者。28 例患者中有 16 例接受了 EGFR-TKI 治疗。大多数接受了第一代 EGFR-TKI，29%的患者单独接受了化疗。EGFR-TKI 组的客观缓解率为 37.5%。EGFR-TKI 组的中位无进展生存期（PFS）为 10.2 个月。8 例接受一线铂类双联化疗的患者中，化疗组的中位 PFS 为 6.5 个月。28 例患者的 3 年总生存率（OS）为 34%。接受 EGFR-TKI 治疗的患者 3 年 OS 明显更好。
在 EGFR 突变 NSCLC 中检测到罕见的 EGFR 突变占 8.8%。外显子 20 插入是最常见的突变，50%的患者有吸烟史。第一代或第二代 EGFR-TKI 为罕见 EGFR 突变 NSCLC 患者带来了更大的 OS 获益，优于铂类双联化疗。生存结果与以前的大型队列研究报告的结果相当。
