• Lin Lai, Wentao Meng, Jialiang Wei, Xiaofei Zhang, Zhiwei Tan, Yunxin Lu, and Encun Hou.
• Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, People's Republic of China.
• Medicine (Baltimore). 2021 Mar 12; 100 (10): e25046e25046.

RationaleGenotypic and histological evolution of non-small-cell lung cancer (NSCLC) into small-cell lung cancer (SCLC) has been described as a mechanism of acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapy. However, the number of clinical cases is rare.Patient ConcernsTwo lung adenocarcinoma patients with EGFR mutations who recurred after radical resection transformed into SCLC under treatment with the sequential first- and third-generation EGFR-TKIs.DiagnosisThe 2 cases were both confirmed as SCLC by pathological rebiopsy after EGFR-TKIs resistance.InterventionsCase 1 was treated with etoposide plus cisplatin (EP) regimen and erlotinib, while case 2 was treated with erlotinib and EP followed by oral etoposide.OutcomesCase 1 treated with EP only achieved 3-month progression-free survival (PFS), which is the first case that reported T790 M/C797S cis-mutation for osimertinib resistance before the SCLC transformation. However, case 2 treated with erlotinib and EP followed by oral etoposide, PFS lasted for 8 months.LessonsThe cases highlighted the importance of rebiopsy that identified pathologically SCLC transformation after EGFR-TKI resistance, and suggested the treatment of erlotinib plus EP followed by etoposide, which could provide a reference for such phenotype.Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.

67 keywords...

hide…