Neoadjuvant savolitinib targeted therapy for stage IIIB-N3 lung adenocarcinoma harboring mesenchymal–epithelial transition exon 14 skipping mutation: a case report and literature review

Savolitinib is a selective inhibitor that specifically targets the phosphorylation of mesenchymal-epithelial transition (MET) kinase. It has demonstrated significant inhibitory effects on the proliferation of tumor cells with METex14 skipping mutation, making it a promising treatment option. While it is the first approved small-molecule inhibitor specifically targeting MET kinase in China, there is limited information about its efficacy as neoadjuvant therapy for patients with supraclavicular lymph node metastasis (N3). In this case report, we presented the successful outcome of a 48-year-old male patient who was diagnosed with stage IIIB (T2bN3M0) lung adenocarcinoma originating from the left upper lobe. The patient exhibited the METex14 skipping alteration. Following two months of neoadjuvant savolitinib treatment, the patient achieved partial remission, with a significant reduction in the size of the primary tumor and metastatic lymph nodes. Postoperative pathological confirmation revealed a pathological complete response, and subsequent imaging examinations, including computed tomography scan and circulating tumor DNA-based molecular residual disease detection, showed no sign of recurrence at 7 months after surgery. Based on this case, neoadjuvant and adjuvant savolitinib therapy may be considered as a favorable alternative to chemotherapy for marginally resectable nonsmall cell lung cancer patients with METex14 skipping mutation.