Supplementary Material for: Lethal immune-related pneumonitis after durvalumab therapy for small cell lung cancer: a first case in China

Introduction: Although programmed death ligand 1 (PD-L1) inhibitor plus chemotherapy regimen is a promising strategy for malignant tumors, it can induce significant immune-related adverse events, such as immune-related pneumonitis. Here we report the first case of lethal immune-related pneumonitis in an Asian patient receiving anti-PD-L1 treatment.
Case presentation: A 68-year-old man was diagnosed with small cell lung cancer and interstitial pneumonia. After his pulmonary infection was relieved by comprehensive treatment, the patient received first-line treatment with durvalumab plus etoposide and carboplatin. Two weeks after starting durvalumab treatment, the patient had chest pain and shortness of breath. He was diagnosed with immune-induced pneumonia and treated with methylprednisolone, cefoperazone and sulbactam, followed by oxygen and pirfenidone. Oxygen partial pressure decreased to 58 mmHg within next the 4 days and laboratory assessment suggested cytokine storm. The patient underwent two plasma exchanges, one double filtration plasmapheresis and oxygen saturation decreased continuously. The patient died one month after durvalumab treatment.
Conclusion: Immune-related pneumonitis induced by PD-L1 inhibitors is rare but life-threatening. Infection should be ruled out before starting immunotherapy.

引言：尽管程序性死亡配体1（PD-L1）抑制剂联合化疗方案是恶性肿瘤颇具前景的治疗策略，但该方案可诱发严重的免疫相关不良事件，例如免疫相关性肺炎。本次报道首例接受抗PD-L1治疗的亚洲患者发生致死性免疫相关性肺炎的临床病例。
病例报告：患者为68岁男性，确诊为小细胞肺癌合并间质性肺炎。经综合治疗后肺部感染得到缓解，随后接受度伐利尤单抗联合依托泊苷与卡铂的一线治疗。启动度伐利尤单抗治疗2周后，患者出现胸痛与呼吸困难，被诊断为免疫相关性肺炎，予甲泼尼龙、头孢哌酮舒巴坦治疗，后续辅以氧疗与吡非尼酮。随后4天内患者动脉血氧分压降至58mmHg，实验室检查提示细胞因子风暴。患者接受2次血浆置换及1次双重滤过血浆置换治疗，但血氧饱和度持续下降，最终在度伐利尤单抗治疗后1个月死亡。
结论：PD-L1抑制剂诱发的免疫相关性肺炎虽罕见，但可危及生命。启动免疫治疗前应排查感染。