Dietary protein and prognosis of hepatocellular carcinoma: a prospective cohort study

Dietary protein has been linked with all-cause and cancer mortality. However, the relationship between dietary protein and the prognosis of hepatocellular carcinoma (HCC) is still unknown. The purpose of this study was to investigate whether dietary protein intake was related to HCC mortality using data from the Guangdong Liver Cancer Cohort (GLCC), a prospective cohort study of HCC survivors established at the Sun Yat-sen University Cancer Center. Dietary information one year before the diagnosis of HCC was obtained through a 79-item semi-quantitative food frequency questionnaire (FFQ). A total of 883 patients with newly diagnosed HCC who were recruited between September 2013 and April 2017 were included in this study. The hazard ratio (HR) and 95% confidence intervals (95% CIs) were estimated by Cox proportional hazard models. The multivariate-adjusted HRs in the highest vs. the lowest tertile of total protein intake were 0.68 (95% CI: 0.52-0.91, P-trend = 0.007) for all-cause mortality and 0.74 (95% CI: 0.55-0.99, P-trend = 0.040) for HCC-specific mortality. However, the associations of animal protein intake, plant protein intake, and animal-to-plant protein ratio with all-cause and HCC-specific mortality were not significant (all P-trend >0.05). Our research suggests that higher prediagnostic dietary intake of total protein was associated with reduced all-cause and HCC-specific mortality.