Real-world status of multimodal treatment of stage IIIA-N2 non-small cell lung cancer in Japan: Results from the solution study, a non-interventional, multicenter cohort study

• Published in: Lung cancer (Amsterdam, Netherlands) Netherlands), 2024-11, Vol.199, p.108027, Article 108027
• Main Authors: Horinouchi, Hidehito, Murakami, Haruyasu, Harada, Hideyuki, Sobue, Tomotaka, Kato, Tomohiro, Atagi, Shinji, Kozuki, Toshiyuki, Tokito, Takaaki, Oizumi, Satoshi, Seike, Masahiro, Ohashi, Kadoaki, Mio, Tadashi, Sone, Takashi, Iwao, Chikako, Iwane, Takeshi, Koto, Ryo, Tsuboi, Masahiro
• Format: Article
• Language: English
• Subjects: Adjuvant therapy; Chemoradiotherapy; Neoadjuvant therapy; Non-small cell lung cancer; Observational study; Retrospective study; Surgery
• ISSN: 0169-5002; 1872-8332; 1872-8332
• DOI: 10.1016/j.lungcan.2024.108027

•We examined the treatment reality and outcomes of Stage IIIA-N2 NSCLC in Japan.•Treatment decisions encompassed multiple factors, including lymph node status.•OS and PFS/DFS varied by number of stations and lymph node appearance.•Survival outcomes tended to favor surgery + perioperative therapy.•Our data could serve as a landmark for decision making and future studies. There is limited consensus on resectability criteria for Stage IIIA-N2 non-small cell lung cancer (NSCLC). We examined the patient characteristics, N2 status, treatment decisions, and clinical outcomes according to the treatment modality for Stage IIIA-N2 NSCLC in Japan. Patients with Stage IIIA-N2 NSCLC in Japan were consecutively registered in SOLUTION study between 2013 and 2014. Patients were divided according to treatment (chemoradiotherapy [CRT], surgery + perioperative therapy [neoadjuvant and/or adjuvant therapy], surgery alone). Demographic characteristics, N2 status (number and morphological features), pathological information, and treatments were analyzed descriptively. Overall survival (OS), progression-free survival (PFS), and disease-free survival (DFS) were estimated using the Kaplan–Meier method. Of 227 patients registered, 133 underwent CRT, 56 underwent surgery + perioperative therapy, and 38 underwent surgery alone. The physicians reported the following reasons for unresectability for 116 of 133 CRT patients: large number of metastatic lymph nodes (70.7 %), extranodal infiltration (25.0 %), poor surgical tolerance (19.0 %), or other reasons (18.1 %). CRT was more frequently performed in patients whose lymph nodes had an infiltrative appearance (64.3 %) and was the predominant treatment in patients with multiple affected stations (discrete: 60.0 %; infiltrative: 80.4 %). Distant metastasis with/without local progression was found in 50.4 %, 50.0 %, and 36.8 % of patients in the CRT, surgery + perioperative therapy, and surgery alone groups, respectively. The respective 3-year OS (median) and DFS/PFS (median) values were as follows: surgery + perioperative therapy—61.9 % (not reached) and 37.1 % (22.4 months; DFS); CRT group—42.2 % (31.9 months; PFS) and 26.8 % (12.0 months); surgery alone group—37.7 % (26.5 months) and 28.7 % (12.6 months; DFS). This study has illuminated the real-world decision rules for choosing between surgical and non-surgical approaches in patients with Stage IIIA-N2 NSCLC. Our landmark data could support treatment decision making for using immune che