Use of crizotinib as neoadjuvant therapy for non‐small cell lung cancers patient with ROS1 rearrangement: A case report

Crizotinib showed significant antitumor effect in patients with advanced ROS1‐rearranged non‐small cell lung cancers (NSCLC). Most recently, many studies have explored the feasibility and efficacy of target therapy for perioperative application in NSCLC. Here, we describe a female patient who was diagnosed with stage IIIB lung adenocarcinoma exhibiting a CCDC6‐ROS1 rearrangement by high‐throughput sequencing. The tumor and lymph nodes showed durable response after the treatment of crizotinib. Given that a radiological downstaging was indicated, a right lower lobectomy and systemic lymphadenectomy were successfully performed. The pathological response was 60% and the tumor, nodes, and metastases (TNM) stage was ypT2bN0M0. The PD‐L1 expression and activity of immunological cells were also investigated. Comprehensive pathological evaluation. (a) Hematoxylin and eosin (HE) staining. Fibrosis and lymphocyte infiltration could be seen on the surgical specimen after crizotinib treatment. (b) Ki67 staining. (c) Multiple immunohistochemistry staining on CD163, CD8, PDL1, CD57, CD68, and PD1 before and after neoadjuvant crizotinib. (d) Quantitative analysis for staining data. *p