Pneumonitis with combined immune checkpoint inhibitors and chemoradiotherapy in locally advanced non-small-cell lung cancer: a systematic review and meta-analysis

Plain language summaryCombined immune checkpoint inhibitors (ICI) and chemoradiotherapy (CRT) may cause severe pneumonitis due to overlapped pulmonary toxicity. However, the safety data on pneumonitis are limited to a small number of prospective clinical trials and retrospective studies with limited evidence. Thus we conducted a systematic review of pneumonitis in relation to the combination treatment. A total of 35 studies, involving 5000 patients, were included for the final analysis. The pooled rates of all-grade, grade 3-5 and grade 5 pneumonitis were 33.0, 6.1 and 0.8%, respectively, and 7.6% of patients stopped taking ICIs because of pneumonitis. The pneumonitis rates following combined CRT and ICIs for LA-NSCLC were acceptable, but the pulmonary toxicity of concurrent CRT and nivolumab plus ipilimumab should be noted. Aims: This study systematically evaluated cases of pneumonitis following combined immune checkpoint inhibitors (ICI) and chemoradiotherapy (CRT) for locally advanced non-small-cell lung cancer (LA-NSCLC). Methods: Studies from Embase, PubMed and the Cochrane Library on patients with LA-NSCLC who received CRT and ICIs were reviewed. The primary outcomes were rates of all-grade, grade 3-5 and grade 5 pneumonitis. Results: Overall, 35 studies involving 5000 patients were enrolled. The pooled rates of all-grade, grade 3-5 and grade 5 pneumonitis were 33.0% (95% CI: 23.5-42.6), 6.1% (95% CI: 4.7-7.4) and 0.8% (95% CI: 0.3-1.2), respectively, with 7.6% of patients discontinuing ICIs because of pneumonitis. Conclusion: The incidence rates of pneumonitis following combined CRT and ICIs for LA-NSCLC were acceptable. However, the pulmonary toxicity of concurrent CRT and nivolumab plus ipilimumab should be noted.