Cruciferous vegetable consumption and the risk of pancreatic cancer: a meta-analysis

BACKGROUND Previous studies regarding the association between cruciferous vegetable intake and pancreatic cancer risk have reported inconsistent results. We conducted a meta-analysis to demonstrate the potential association between them. METHODS A systematic literature search of papers was conducted in March 2014 using PubMed, EMBASE, and Web of Science, and the references of the retrieved articles were screened. The summary odds ratios (ORs) with 95% confidence interval (CI) for the highest versus the lowest intake of cruciferous vegetables were calculated. RESULTS Four cohort and five case-control studies were eligible for inclusion. We found a significantly decreased risk of pancreatic cancer associated with the high intake of cruciferous vegetables (OR 0.78, 95% CI 0.64-0.91). Moderate heterogeneity was detected across studies (P = 0.065). There was no evidence of significant publication bias based on Begg's funnel plot (P = 0.917) or Egger's test (P = 0.669). CONCLUSIONS Cruciferous vegetable intake might be inversely associated with pancreatic cancer risk. Because of the limited number of studies included in this meta-analysis, further well-designed prospective studies are warranted to confirm the inverse association between cruciferous vegetable intake and risk of pancreatic cancer.