Effect of dietary consumption on the survival of esophageal squamous cell carcinoma: a prospective cohort study

Background/Objectives This prospective cohort study was to assess the association of pre-diagnostic dietary intake and dietary pattern with the survival of esophageal squamous cell carcinoma (ESCC) patients. Subjects/Methods 855 patients were recruited and successfully followed. Information on diet over past five years before diagnosis was collected using a food frequency questionnaire, and dietary patterns were extracted using principal component analysis. Hazard ratio (HR) with 95% confidence interval (95% CI) was calculated using the Cox proportional hazard model. Results 164 (19.18%) ESCC patients survived during the follow-up. Every 25-g increment intake of pickled vegetables was associated with a 6.0% (HR: 1.060, 95% CI: 1.003-1.121) increased risk of death after adjustment for covariates. When comparing the highest with lowest tertiles of energy-adjusted intake, pickled vegetables intake was associated with a 21.9% elevated risk of death (HR: 1.219, 95% CI: 1.014-1.465), while fish and shrimp intake was associated with a 19.4% (HR: 0.816, 95% CI: 0.675-0.986) reduced risk of death. Three dietary patterns were defined and labeled as patterns I, II, and III. Every 10-score increment of dietary pattern II, characterized with a higher loading of preserved vegetables, pickled vegetables, and salted meat, was associated with a 1.7% (HR: 1.017, 95% CI: 1.003-1.032) increased risk of death. Conclusions A diet characterized with higher loading of preserved vegetables, pickled vegetables, and salted meat, was negatively associated with death risk among ESCC patients. Prospective studies concerning the role of post-diagnosis dietary intake in ESCC prognosis are needed.