Yang Zhao, Wong Irene Ol, Deng Wei, Chen Ru, Zhou Jiachen, Wei Wenqiang
School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 999077, China.
Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiation Oncology, Peking University Cancer Hospital & Institute, Beijing 100142, China.
Chin J Cancer Res. 2020 Aug;32(4):467-475. doi: 10.21147/j.issn.1000-9604.2020.04.04.
To investigate what extent lead-time bias is likely to affect endoscopic screening effectiveness for esophageal cancer in the high-risk area in China.
A screening model based on the epidemiological cancer registry data, yielding a population-level incidence and mortality rates, was carried out to simulate study participants in the high-risk area in China, and investigate the effect of lead-time bias on endoscopic screening with control for length bias.
Of 100,000 participants, 6,150 (6.15%) were diagnosed with esophageal squamous dysplasia during the 20-year follow-up period. The estimated lead time ranged from 1.67 to 5.78 years, with a median time of 4.62 years [interquartile range (IQR): 4.07-5.11 years] in the high-risk area in China. Lead-time bias exaggerated screening effectiveness severely, causing more than a 10% overestimation in 5-year cause-specific survival rate and around a 43% reduction in cause-specific hazard ratio. The magnitude of lead-time bias on endoscopic screening for esophageal cancer varied depending on the screening strategies, in which an inverted U-shaped and U-shaped effects were observed in the 5-year cause-specific survival rate and cause-specific hazard ratio respectively concerning a range of ages for primary screening.
Lead-time bias, usually causing an overestimation of screening effectiveness, is an elementary and fundamental issue in cancer screening. Quantification and correction of lead-time bias are essential when evaluating the effectiveness of endoscopic screening in the high-risk area in China.
探讨领先时间偏倚在多大程度上可能影响中国高风险地区食管癌内镜筛查的效果。
基于癌症流行病学登记数据建立一个筛查模型，得出人群水平的发病率和死亡率，用于模拟中国高风险地区的研究参与者，并在控制长度偏倚的情况下研究领先时间偏倚对内镜筛查的影响。
在100,000名参与者中，6150名（6.15%）在20年随访期内被诊断为食管鳞状上皮发育异常。在中国高风险地区，估计的领先时间为1.67至5.78年，中位时间为4.62年[四分位间距（IQR）：4.07 - 5.11年]。领先时间偏倚严重夸大了筛查效果，导致5年病因特异性生存率高估超过10%，病因特异性风险比降低约43%。食管癌内镜筛查中领先时间偏倚的程度因筛查策略而异，其中在不同年龄范围的初次筛查中，5年病因特异性生存率和病因特异性风险比分别呈现倒U形和U形效应。
领先时间偏倚通常会导致对筛查效果的高估，是癌症筛查中的一个基本问题。在中国高风险地区评估内镜筛查效果时，对领先时间偏倚进行量化和校正至关重要。
