简介：AbstractBackground:Family clustering of esophageal cancer (EC) has been found in high-risk areas of China. However, the relationships between cancer family history and esophageal cancer and precancerous lesions (ECPL) have not been comprehensively reported in recent years. This study aimed to provide evidence for identification of high-risk populations.Methods:This study was conducted in five high-risk areas in China from 2017 to 2019, based on the National Cohort of Esophageal Cancer. The permanent residents aged 40 to 69 years were examined by endoscopy, and pathological examination was performed for suspicious lesions. Information on demographic characteristics, environmental factors, and cancer family history was collected. Unconditional logistic regression was applied to evaluate odds ratios between family history related factors and ECPL.Results:Among 33,008 participants, 6143 (18.61%) reported positive family history of EC. The proportion of positive family history varied significantly among high-risk areas. After adjusting for risk factors, participants with a family history of positive cancer, gastric and esophageal cancer or EC had 1.49-fold (95% confidence interval [CI]: 1.36-1.62), 1.52-fold (95% CI: 1.38-1.67), or 1.66-fold (95% CI: 1.50-1.84) higher risks of ECPL, respectively. Participants with single or multiple first-degree relatives (FDR) of positive EC history had 1.65-fold (95% CI: 1.47-1.84) or 1.93-fold (95% CI: 1.46-2.54) higher risks of ECPL. Participants with FDRs who developed EC before 35, 45, and 50 years of age had 4.05-fold (95% CI: 1.30-12.65), 2.11-fold (95% CI: 1.37-3.25), and 1.91-fold (95% CI: 1.44-2.54) higher risks of ECPL, respectively.Conclusions:Participants with positive family history of EC had significantly higher risk of ECPL. This risk increased with the number of EC positive FDRs and EC family history of early onset. Distinctive genetic risk factors of the population in high-risk areas of China require further investigation.Trial registration:ChiCTR-EOC-17010553.