Impact of lymph node micrometastasis on gastric carcinoma prognosis:A meta-analysis

AIM:To investigate the prognostic significance of lymph node micrometastasis(LNMM) in patients with gastric carcinoma.METHODS:Two reviewers independently searchedelectronic databases including Pub Med,EMBASE,the Cochrane Database of Systematic Reviews,the Cochrane Controlled Studies Register,and the China National Knowledge Infrastructure electronic database between January 1996 and January 2014.Strict literature retrieval and data extraction were performed to extract relevant data.Data analysis was conducted using Rev Man 5.2.4 software,and relative risks(RRs) for patient death in five years and recurrence were calculated.A fixed- or random-effects model was selected to pool and a forest plot was used to display RRs.RESULTS:Twelve cohort studies containing a total of 1684 patients were identified.LNMM positivity was worse than LNMM negativity with regards to the number of patients who died in five years.The effects of LNMM positivity in patients with gastric cancer of different T-stages remain unclear.LNMM in patients with gastric carcinoma was also associated with a higher recurrence rate.With regards to the number of patients who died in five years,Asian patients were worse than European and Australian patients.CONCLUSION:We recommend that LNMM should not be used as a gold standard for prognosis evaluation in patients with gastric cancer in clinical settings until more high quality trials are available.

Extended antimicrobial prophylaxis after gastric cancer surgery: A systematic review and meta-analysis

AIM: To investigate the efficacy of extended antimicrobial prophylaxis (EAP) after gastrectomy by systematic review of literature and meta-analysis. METHODS: Electronic databases of PubMed, Embase, CINAHL, the Cochrane Database of Systematic Reviews, the Cochrane Controlled Trials Register and the China National Knowledge Infrastructure were searched systematically from January 1980 to October 2012. Strict literature retrieval and data extraction were carried out independently by two reviewers and meta-analyses were conducted using RevMan 5.0.2 with statistics tools risk ratios (RRs) and intention-to-treat analyses to evaluate the items of total complications, surgical site infection, incision infection, organ (or space) infection, remote site infection, anastomotic leakage (or dehiscence) and mortality. Fixed model or random model was selected accordingly and forest plot was conducted to display RR. Likewise, Cochrane Risk of Bias Tool was applied to evaluate the quality of randomized controlled trials (RCTs) included in this meta-analysis. RESULTS: A total of 1095 patients with gastric cancer were enrolled in four RCTs. No statistically significant differences were detected between EAP and intraoperative antimicrobial prophylaxis (IAP) in total complications (RR of 0.86, 95%CI: 0.63-1.16, P = 0.32), surgical site infection (RR of 1.97, 95%CI: 0.86-4.48, P = 0.11), incision infection (RR of 4.92, 95%CI: 0.58-41.66, P = 0.14), organ or space infection (RR of 1.55, 95%CI: 0.61-3.89, P = 0.36), anastomotic leakage or dehiscence (RR of 3.85, 95%CI: 0.64-23.17, P = 0.14) and mortality (RR of 1.14, 95%CI: 0.10-13.12; P = 0.92). Likewise, multiple-dose antimicrobial prophylaxis showed no difference compared with single-dose antimicrobial prophylaxis in surgical site infection (RR of 1.10, 95%CI: 0.62-1.93, P = 0.75). Nevertheless, EAP showed a decreased remote site infection rate compared with IAP alone (RR of 0.54, 95%CI: 0.34-0.86, P = 0.01), which is the only significant finding. Unfortunately, EAP did not decrease the incidence of surgical site infections after gastrectomy; likewise, multipledose antimicrobial prophylaxis failed to decrease the incidence of surgical site infection compared with single-dose antimicrobial prophylaxis. CONCLUSION: We recommend that EAP should not be used routinely after gastrectomy until more high-quality RCTs are available.