Family history of esophageal cancer increases the risk of esophageal squamous cell carcinoma

A population-based case-control was performed to explore familial aggregation of esophageal squamous cell carcinoma (ESCC). Family history of cancer was assessed by a structured questionnaire, and from which 2 cohorts of relatives of cases and controls were reconstructed. Unconditional logistic regression and Cox proportional hazards regression were applied for case-control design and reconstructed cohort design, respectively. We observed a close to doubled risk of ESCC associated with a positive family history of esophageal cancer among first degree relatives (odds ratio [OR] = 1.85, 95% confidence interval [CI]: 1.42-2.41), after adjusting age, sex, family size and other confounders. The excess risks of ESCC increased with the increasing of first-degree relatives affected by esophageal cancer (p < 0.001). In particular, those individuals whose both parents with esophageal cancer had an 8-fold excess risk of ESCC (95% CI: 1.74-36.32). The reconstructed cohort analysis showed that the cumulative risk of esophageal cancer to age 75 was 12.2% in the first-degree relatives of cases and 7.0% in those of controls (hazard ratio = 1.91, 95% CI: 1.54-2.37). Our results suggest family history of esophageal cancer significantly increases the risk for ESCC. Future studies are needed to understand how the shared genetic susceptibility and/or environmental exposures contribute to the observed excess risk.