Dan Li,* Xin Liu,* Yang Liu, Yue Zhu, Dafu Yang, Jincheng Song, Zhaoxia Dai

Department of Medical Oncology, The Second Hospital of Dalian Medical University, Dalian, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Jincheng Song, Department of Medical Oncology, The Second Hospital of Dalian Medical University, No. 467, Zhongshan Road, Shahekou District, Dalian, People’s Republic of China, Email wwepqwq@163.com Zhaoxia Dai, Department of Medical Oncology, The Second Hospital of Dalian Medical University, No. 467, Zhongshan Road, Shahekou District, Dalian, People’s Republic of China, Email dzx21882003@163.com

Abstract: The effectiveness of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) has been established, leading the NCCN Guidelines to recommend it as a first-line treatment for patients with advanced EGFR mutation-positive non-small cell lung cancer (NSCLC). However, there is still controversy about the use of neoadjuvant TKI treatment for patients with stage III EGFR mutation-positive NSCLC. Here, we firstly report that a stage IIIA lung adenocarcinoma patient benefited from chemotherapy and dacomitinib as neoadjuvant targeted therapy based on EGFR G719X mutation, achieving a pathological downstaging and the chance of radical surgical resection. Our case describes dacomitinib use as neoadjuvant targeted therapy for EGFR positive advanced NSCLC and highlights the application of molecular testing for the better treatment decision making.

Keywords: uncommon EGFR mutations, EGFR G719X, neoadjuvant targeted therapy, dacomitinib, NSCLC