BACKGROUND/OBJECTIVESThis study aimed to investigate the association of dietary patterns with overweight risk and all-cause mortality in pediatric cancer patients.SUBJECTS/METHODSProspective cohort study was undertaken; 83 cancer patients admitted to the pediatric cancer ward at a university hospital in Seoul were included and followed for obesity and death over 24 months. Food consumption data were collected from patients using validated meal order sheets for breakfast, lunch, and dinner at the pediatric cancer ward over 3 days. Using principal component analysis, three dietary patterns were derived from 29 food groups.RESULTSEighteen deaths occurred among the patient cohort during the follow-up period. The “spicy & fried meat and fish” dietary pattern was positively associated with overweight risk at both baseline [odds ratio (OR) = 4.396, 95% confidence interval (CI) = 1.111-17.385, P for trend = 0.023] and after 6 months (OR = 4.088, 95% CI = 1.122-14.896, P for trend = 0.025) as well as all-cause mortality (hazard ratios = 5.124, 95% CI = 1.080-24.320, P for trend = 0.042), when comparing the highest and lowest tertiles after adjusting for covariates. The “fish, egg, meat, and fruits & vegetables” dietary pattern was associated with lower overweight risk after 24 months (OR = 0.157, 95% CI = 0.046-0.982, P for trend = 0.084).CONCLUSIONThe results imply that dietary patterns might be associated with weight gain and premature death among pediatric cancer patients.