Diet and Esophageal Cancer Risk: An Umbrella Review of Systematic Reviews and Meta-Analyses of Observational Studies.

Diet may play an important role in the occurrence of esophageal cancer (EC). The aim of this umbrella review was to grade the evidence for the association between dietary factors and EC risk. A protocol for this review was registered with the PROSPERO database (CRD42021283232). Publications were identified by searching PubMed, EMBASE, Web of Science, Cochrane Database of Systematic Reviews, and CINAHL databases. Only systematic reviews and meta-analyses of observational studies (cohort studies, case-cohort studies, nested case-control studies) were eligible. AMSTAR-2 (A Measurement Tool to Assess Systematic Reviews) was used to assess the methodological quality of included systematic reviews. For each association, random-effects pooled effect size, 95% CI, number of cases, 95% prediction interval, heterogeneity, small-study effect, and excess significance bias were calculated to grade the evidence. From 882 publications, 107 full-text articles were evaluated for eligibility, and 20 systematic reviews and meta-analyses describing 32 associations between dietary factors and EC risk were included in the present umbrella review. By assessing the strength and validity of the evidence, 1 association (positively associated with alcohol intake) was supported by highly suggestive evidence and 1 (inversely associated with calcium intake) showed a suggestive level of evidence. Evidence for 7 associations was weak (positively associated with red meat and processed-meat intake; inversely associated with whole grains, fruits, green leafy vegetables, green tea, and zinc intake). The remaining 23 associations were nonsignificant. In conclusion, the findings of this umbrella review emphasize that habitually consuming calcium, whole grains, fruits, green leafy vegetables, green tea, and zinc and reducing alcohol, red meat, and processed-meat intake are associated with a lower risk of EC. Since this umbrella review included only observational study data and some of the associations were graded as weak, caution should be exercised in interpreting these relations.

Does intravenous fish oil benefit patients post-surgery? A meta-analysis of randomised controlled trials.

BACKGROUND AND AIMS: Supplementation of fish oil (FO) containing lipid emulsions has been associated with a reduction in the length of hospital stay, infections and liver dysfunction in patients undergoing major surgery. We carried out a meta-analysis and subgroup analysis to examine randomised clinical trial (RCT)-based evidence of the aforementioned effects. METHODS: Four databases, reference lists and the WHO ICTRP were systematically searched for RCTs to access the clinical efficacy of fish oil-enriched total parenteral nutrition in post-surgery patients. Methodological quality assessment was based on the Cochrane Handbook and GRADE. RESULTS: Twenty-one RCTs were enrolled for meta-analysis. FO was associated with a significant reduction in the length of hospital stay (mean = -2.14 d, 95% CI = -3.02 to -1.27), infections (OR = 0.53, 95% CI = 0.35-0.81), ALT (mean = -6.35 U/L, 95% CI = -11.75 to -0.94), GGT (mean = -11.01 U/L, 95% CI = -20.77 to -1.25) and total bilirubin (mean = -2.06 µmol/L, 95% CI = -3.6 to -0.52), as well as a non-significant change in mortality and postoperative medical cost. The quality of evidence of each clinical outcome was accessed as high. CONCLUSION: FO-enriched lipid emulsions are likely to reduce infections, the length of hospital stay and liver dysfunction without influencing mortality and may be a safe and preferable choice in post-surgery patients. Further well-designed trials should be performed to determine whether FO lipid emulsions reduce mortality in patients undergoing hepatic surgery, especially liver transplantation, and the cost effectiveness of such treatment.

[Clinical observation of preoperative administration of enteral nutrition support in gastric cancer patients at risk of malnutrition].

OBJECTIVE: To evaluate safety and efficacy of preoperative administration of enteral nutrition support in gastric cancer patients at risk of malnutrition. METHODS: A single center randomized controlled clinical trial was performed in 60 gastric cancer patients in West China Hospital from May to October 2012. Thirty patients were given enteral nutrition support(Ensure(R)) manufactured by Abbott Laboratories for ten consecutive days before surgical operation in the treatment group, and 30 patients were given an isocaloric and isonitrogenous homogenized diet in the control group for 10 days as well. The laboratory parameters of nutritional status and hepatorenal function were observed and compared between the two groups on admission, preoperative day 1 and postoperative day 3, respectively. Clinical observations, such as nausea and vomiting, were carried out until patients were discharged. RESULTS: Before the intervention, there were no significant differences in the baseline characteristics between the two groups. The levels of serum albumin [(33.9±5.6) g/L vs. (31.0±5.3) g/L, P<0.05], and hemoglobin[(103.4±7.7) g/L vs.(96.6±10.5) g/L, P<0.01] were significantly improved in the treatment group on postoperative day 3. However, the levels of body mass index, lymphocyte count, liver and renal function, serum glucose, sodium, and potassium were not significantly different between the two groups(all P>0.05). Moreover, two patients with nausea and one with vomiting in each group were found. In clinical observation period, no severe treatment-related adverse event were observed. CONCLUSION: The enteral supplement with Ensure(R) in gastric cancer patients at risk of malnutrition during preoperative period is effective and safe, which is superior to homogenized diet and an appropriate choice for gastric cancer patients with nutritional risk.