免疫检查点抑制剂相关肺炎的临床及CT表现分析

Clinical and CT imaging features of immune checkpoint inhibitor-associated pneumonia

目的探讨免疫检查点抑制剂相关肺炎(CIP)的临床及CT影像学特点,以期提高对该病的早期诊断能力。方法回顾性分析2020年6月1日至2021年10月31日解放军总医院第一医学中心所有接受免疫检查点抑制剂(ICI)治疗的2067例恶性肿瘤患者的临床资料及系列胸部CT图像,并按照CIP诊断指南纳入CIP患者,分析其发生率、开始用药至出现CIP时间、用药周期、影像学特征、影像学模式、CT分级及转归等。采用χ^(2)检验比较有、无肺基础疾病患者CIP的发生率。结果2067例接受ICI治疗的恶性肿瘤患者中,67例出现CIP,CIP发生率为3.2%。386例肺部有基础病变患者CIP发病率(7.00%,27/386)与1681例肺部无基础病变患者CIP发病率(2.4%,40/1681)差异有统计学意义(χ^(2)=21.32,P<0.001)。开始用药至出现CIP时间为7~367 d,中位时间52 d,用药1~12周期,中位周期为2周期。CIP的影像学征象以磨玻璃影(54例,80.6%)、实性结节(26例,38.8%)、实变(25例,37.3%)、网格影(24例,35.8%)为主;CT表现模式以机化性肺炎(OP)模式(34例,50.7%)最多,其次是弥漫性肺泡损伤(DAD)模式(14例,20.9%);CT表现分级为低危级26例,中危级17例,高危级24例;43例低、中危级患者中OP样25例,占比58.1%,24例高危级患者中DAD样13例,占比54.2%。52例随访病例中43例初始未干预,其中23例患者病灶进展,17例病灶缩小,3例病灶完全吸收。随访患者中8例病灶吸收后或停药后出现复发。结论CIP患者的影像表现以磨玻璃影、实性结节、实变、网格为主,影像学表现模式以OP和DAD模式为主,高危级别中DAD占比最高,低、中危级别中OP占比最高。有肺基础病患者更容易得CIP。

Objective To explore the clinical and CT imaging features of immune checkpoint inhibitor-associated pneumonia(CIP)and to improve the early diagnostic ability of CIP.Methods From June 1,2020 to October 31,2021,the clinical data and chest CT images of 2067 patients with advanced malignant tumor treated with immune checkpoint inhibitor(ICI)in the First Medical Center,Chinese PLA General Hospital were retrospectively analyzed.Patients with CIP were enrolled according to the guidelines for CIP diagnosis,and the incidence,time from the start of medication to the onset of CIP,medication cycle,imaging features,imaging patterns,CT grade and outcomes were analyzed.χ^(2) test was used to compare the incidence of CIP in patients with or without basic lung disease.Results Among 2067 patients with malignant tumors treated with ICI,67 patients developed CIP,the incidence of CIP was 3.2%.The incidence of CIP was significantly different between 386 patients with basic lung disease(7.00%,27/386)and 1681 patients without basic lung disease(2.4%,40/1681)(χ^(2)=21.32,P<0.001).The time from the start of medication to the onset of CIP was 7-367 d(median 52 days),and the duration of medication was 1-12 cycles(median 2 cycles).The imaging features of CIP presented as ground glass opacities in 54 cases(80.6%),solid nodules in 26 cases(38.8%),consolidations in 25 cases(37.3%)and irregular reticular opacities in 24 cases(35.8%).The main radiologic pattern was organizing pneumonia(OP,34 cases,50.7%),and followed by diffuse alveolar damage(DAD)pattern(14 cases,20.9%).According to CT grading,there were 26 cases in low risk grade,17 cases in moderate risk grade and 24 cases in high risk grade.Of 43 low-and medium-risk grade cases,25 were OP pattern,accounting for 58.1%,and among 24 high-risk grade patients,13 were DAD pattern,accounting for 54.2%.Forty-three of the 52 patients were initially untreated,of which 23 patients progressed,17 had lesion shrinkage,and 3 had resolution,and relapsed in 8 cases after resolution or drug withdrawal.Conclusions The imaging manifestations of CIP are mainly ground glass opacities,nodules,consolidations,and irregular reticular opacities.The radiologic patterns are mainly OP and DAD.OP is the most common pattern in low-moderate risk grade CIP and DAD is the most common pattern in high risk grade CIP.Patients with basic lung disease are more likely to get CIP.