A Retrospective Study of the Efficacy and Safety of Chemoimmunotherapy in Elderly Patients with Extensive-Stage Small Cell Lung Cancer
Minoru Kobayashi, Satoshi Watanabe, Shinji Hirose, Hiroki Watanabe, Kohei Kushiro, Ryo Suzuki, Naohiro Yanagimura, Miyuki Sato, Tomohiro Tanaka, Koichiro Nozaki, Yu Saida, Jun Arinami, Yuka Goto, Ko Sato, Daisuke Ishikawa, Takao Miyabayashi, Kosuke Ichikawa, Naoya Matsumoto, Jun Koshio, Yoshiki Hayashi, Kenichi Koyama, Masato Makino, Hideyuki Kuriyama, Ryohei Terashima, Atsushi Hashimoto, Toshiaki KikuchiBackground/Objectives: We evaluated the efficacy and safety of first-line treatment with a programmed death-ligand 1 (PD-L1) inhibitor plus platinum-based chemotherapy versus chemotherapy alone in patients aged ≥75 years with extensive-stage small cell lung cancer (ES-SCLC). Methods: We retrospectively analyzed the patients with ES-SCLC treated within the Niigata Lung Cancer Treatment Study Group between August 2019 and April 2024. Results: A total of 364 consecutive patients were enrolled. After excluding 21 patients who did not receive treatment or had ineligible histological types, 343 patients were included in the analysis. Of these, 132 were aged ≥75. Compared with chemotherapy alone, administering a PD-L1 inhibitor with chemotherapy significantly improved the median overall survival among elderly patients (13.6 vs. 8.4 months; hazard ratio, 0.543; p = 0.0277). The median progression-free and overall survivals were similar between the ≥75-year and <75-year groups treated with PD-L1 inhibitor plus chemotherapy (4.9 vs. 4.8 months; p = 0.7611 and 13.6 vs. 15 months; p = 0.732, respectively). Immune-related adverse events (irAE) of ≥grade 3 occurred in 4 and 12 patients (p = 0.7823), and non irAE of ≥grade 3 occurred in 47 and 103 patients (p = 0.5247) in the ≥75-years and <75-years subgroups, respectively. Conclusions: In this retrospective study, among patients aged ≥75 years with ES-SCLC, the addition of a PD-L1 inhibitor to platinum-based chemotherapy was associated with longer overall survival. Progression-free and overall survival outcomes were comparable between elderly and younger patients, with no clear age-related difference observed in the incidence of adverse events of ≥grade 3.