AUTHOR=Zhang Hao , Xia Wei , Zhang Yifan , Bao Shihao , Zeng Jingtong , Li Xianjie , Zhang Bo , Wang Hanqing , Xu Song , Song Zuoqing TITLE=Ensartinib as a neoadjuvant therapy for stage IIIA non-small cell lung cancer patients with EML4-ALK fusion: a case report and literature review JOURNAL=Frontiers in Oncology VOLUME=Volume 15 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2025.1474997 DOI=10.3389/fonc.2025.1474997 ISSN=2234-943X ABSTRACT=Anaplastic lymphoma kinase (ALK) inhibitors have shown efficacy in treating ALK-positive advanced non-small cell lung cancer (NSCLC) patients. However, the effectiveness of ensartinib neoadjuvant therapy remains ambiguous. Herein, we reported that preoperative systemic treatment with the ALK inhibitor ensartinib can be beneficial for treating initially inoperable tumors. In this study, we present a case of a 60-year-old female patient who was diagnosed with stage IIIA (cT2aN2aM0, ninth TNM stage) lower left lung adenocarcinoma harboring an EML4-ALK fusion. After three months of therapy, the neoadjuvant treatment with ensartinib provided a partial response, with significant tumor and lymph node shrinkage. Preoperative ensartinib neoadjuvant therapy for NSCLC is safe and effective. Nevertheless, clinical trials can be conducted in the future to validate our results. Moreover, we performed multiple immunofluorescence staining analyses on samples before and after neoadjuvant therapy, observed and compared the changes in the expression of relevant immune cells (CD8+ T cells, macrophages, PD-1, and PD-L1), and performed a simple analysis.