Yuanchuan Zhang

Transthoracic vs transhiatal surgery for cancer of the esophagogastric junction: A meta-analysis

AIM To compare the efficacy and safety of the transthoracic and transhiatal approaches for cancer of the esophagogastric junction. METHODS An electronic and manual search of the literature was conducted in PubMed, EmBase and the Cochrane Library for articles published between March 1998 and January 2013. The pooled data included the following parameters: duration of surgical time, blood loss, dissected lymph nodes, hospital stay time, anastomotic leakage, pulmonary complications, cardiovascular complications, 30-d hospital mortality, and long-term survival. Sensitivity analysis was performed by excluding single studies. RESULTS Eight studies including 1155 patients with cancer of the esophagogastric junction, with 639 patients in the transthoracic group and 516 in the transhiatal group, were pooled for this study. There were no significant differences between two groups concerning surgical time, blood loss, anastomotic leakage, or cardiovascular complications. Dissected lymph nodes also showed no significant differences between two groups in randomized controlled trials (RCTs) and non-RCTs. However, we did observe a shorter hospital stay (WMD = 1.92, 95%CI: 1.63-2.22, P < 0.00001), lower 30-d hospital mortality (OR = 3.21, 95%CI: 1.13-9.12, P = 0.03), and decreased pulmonary complications (OR = 2.95, 95%CI: 1.95-4.45, P < 0.00001) in the transhiatal group. For overall survival, a potential survival benefit was achieved for type III tumors with the transhiatal approach. CONCLUSION The transhiatal approach for cancers of the esophagogastric junction, especially types III, should be recommended, and its long-term outcome benefits should be further evaluated.

Impact of XRCC2 Arg188His Polymorphism on Cancer Susceptibility: A Meta-Analysis

Background Association between the single nucleotide polymorphism rs3218536 (known as Arg188His) located in the X-ray repair cross complementing group 2 (XRCC2) gene and cancer susceptibility has been widely investigated. However, results thus far have remained controversial. A meta-analysis was performed to identify the impact of this polymorphism on cancer susceptibility. Methods PubMed and Embase databases were searched systematically until September 7, 2013 to obtain all the records evaluating the association between the XRCC2 Arg188His polymorphism and the risk of all types of cancers. We used the odds ratio (OR) as measure of effect, and pooled the data in a Mantel-Haenszel weighed random-effects meta-analysis to provide a summary estimate of the impact of this polymorphism on breast cancer, ovarian cancer and other cancers. All the analyses were carried out in STATA 12.0. Results With 30868 cases and 38656 controls, a total of 45 case-control studies from 26 publications were eventually included in our meta-analysis. No significant association was observed between the XRCC2 Arg188His polymorphism and breast cancer susceptibility (dominant model: OR = 0.94, 95%CI = 0.86–1.04, P = 0.232). However, a significant impact of this polymorphism was detected on decreased ovarian cancer risk (dominant model: OR = 0.83, 95%CI = 0.73–0.95, P = 0.007). In addition, we found this polymorphism was associated with increased upper aerodigestive tract (UADT) cancer susceptibility (dominant model: OR = 1.51, 95%CI = 1.04–2.20, P = 0.032). Conclusion The Arg188His polymorphism might play different roles in carcinogenesis of various cancer types. Current evidence did not suggest that this polymorphism was directly associated with breast cancer susceptibility. However, this polymorphism might contribute to decreased gynecological cancer risk and increased UADT cancer risk. More preclinical and epidemiological studies were still imperative for further evaluation.

Is Dor fundoplication optimum after laparoscopic Heller myotomy for achalasia? A meta-analysis

AIM To compare the outcome of acid reflux prevention by Dor fundoplication after laparoscopic Heller myotomy (LHM) for achalasia. METHODS Electronic database PubMed, Ovid (Evidence-Based Medicine Reviews, EmBase and Ovid MEDLINE) and Cochrane Library were searched between January 1995 and September 2012. Bibliographic citation management software (EndNote X3) was used for extracted literature management. Quality assessment of random controlled studies (RCTs) and non-RCTs was performed according to the Cochrane Handbook for Systematic Reviews of Interventions 5.1.0 and a modification of the Newcastle-Ottawa Scale, respectively. The data were analyzed using Review Manager (Version 5.1), and sensitivity analysis was performed by sequentially omitting each study. RESULTS Finally, 6 studies, including a total of 523 achalasia patients, compared Dor fundoplication with other types of fundoplication after LHM (Dor-other group), and 8 studies, including a total of 528 achalasia patients, compared Dor fundoplication with no fundoplication after LHM (Dor-no group). Dor fundoplication was associated with a significantly higher recurrence rate of clinical regurgitation and pathological acid reflux compared with the other fundoplication group (OR = 7.16, 95%CI: 1.25-40.93, P = 0.03, and OR = 3.79, 95%CI: 1.23-11.72, P = 0.02, respectively). In addition, there were no significant differences between Dor fundoplication and no fundoplication in all subjects. Other outcomes, including complications, dysphagia, postoperative physiologic testing, and operation-related data displayed no significant differences in the two comparison groups. CONCLUSION Dor fundoplication is not the optimum procedure after LHM for achalasia. We suggest more attention should be paid on quality of life among different fundoplications.

The impact of general/visceral obesity on completion of mesorectum and perioperative outcomes of laparoscopic TME for rectal cancer: A STARD-compliant article.

AbstractTo evaluate the impact of visceral obesity on laparoscopic total mesorectal excision (TME) and decide the best index to reflect completion of mesorectum and perioperative outcomes.Patients with rectal cancer who underwent laparoscopic TME were enrolled. The data including body mass index (BMI), visceral fat area (VFA), visceral fat area/body surface area (VFA/BSA), mesorectum fat ratio (MFR), pelvic fat area (PFA), pelvic fat ratio (PFR), completion of mesorectum, and other perioperative outcomes were collected. Data were analyzed.A total of 322 patients were enrolled between 2011 and 2014. There was no significantly difference between the BMI groups on completion of mesorectum and other outcomes (P ≥ 0.05). However, in VFA groups, completion of mesorectum (P = 0.002), operative time (P = 0.02), and incision length (P = 0.02) were significantly different. In VFA/BSA groups, completion of mesorectum (P = 0.002) and incision length (P = 0.009) were significantly different. When MFR was equal to 0.48, completion of mesorectum (P = 0.002), operative time (P = 0.001), incision length (P = 0.03), and blood loss (P = 0.04) were significantly different between the 2 groups. In PFA and PFR groups, there was no significantly difference (P ≥ 0.05). After the analysis of logistic regression, only VFA was the risk factor of incomplete mesorectum excision.BMI does not reflect the impact of obesity on laparoscopic rectal surgery. VFA is a better index in predicting the influence of visceral obesity on surgical quality and difficulty of laparoscopic rectal surgery than VFA/BSA and MFR.

NBS1 Glu185Gln polymorphism and cancer risk: update on current evidence

A number of studies have investigated the association between NBS1 Glu185Gln (rs1805794, E185Q) polymorphism and cancer risk, but the results remained controversial. Previous meta-analysis found a borderline significant impact of this polymorphism on cancer risk; however, the result might be relatively unreliable due to absence of numerous newly published studies. Thus, we conducted an updated meta-analysis. A systematic search was performed in PubMed and Embase databases until April 9, 2013. The odds ratios were pooled by the fixed-effects/random-effects model in STATA 12.0 software. As a result, a total of 48 case–control studies with 17,159 cases and 22,002 controls were included. No significant association was detected between the Glu185Gln polymorphism and overall cancer risk. As to subgroup analysis by cancer site, the results showed that this polymorphism could increase the risk for leukemia and nasopharyngeal cancer. Notably, the Glu185Gln polymorphism was found to be related to increased risk for urinary system cancer, but decreased risk for digestive system cancer. No significant associations were obtained for other subgroup analyses such as ethnicity, sample size and smoking status. In conclusion, current evidence did not suggest that the NBS1 Glu185Gln polymorphism was associated with overall cancer risk, but this polymorphism might contribute to the risk for some specific cancer sites due to potential different mechanisms. More well-designed studies are imperative to identify the exact function of this polymorphism in carcinogenesis.

Prophylaxis for Venous Thromboembolism After Laparoscopic Surgery for Colorectal Cancer: 1 Week or 4 Week?

To the Editor: We read with great interest the article by Vedovati et al. This study concluded that 4-week antithrombotic prophylaxis after laparoscopic colorectal cancer surgery is safe in respect of few bleeding complications and is better than 1-week prophylaxis in reducing the risk of venous thromboembolism (VTE). Nevertheless, we believe there are some issues to be clarified. This study excluded 46 patients at day 8 2 after surgery because they were diagnosed with deep vein thrombosis (DVT) by complete compression ultrasonography. Patients could have VTE at the diagnosis of malignant tumor, for which the application of low-molecular-weight heparin (LMWH) should not be called prophylaxis. As a result, these patients were excluded. However, because no complete compression ultrasonography or other tests for VTE were taken before surgery, patients among the excluded 46 patients may have developed DVT after the surgery. For them, prophylaxis actually failed to prevent VTE. Thus, the study may overrate the effectiveness of LMWH prophylaxis and the conclusion of