Pouch Roux-en-Y vs No Pouch Roux-en-Y following total gastrectomy: a meta-analysis based on 12 studies

2011-02-24 02:55LiangZongPingChenYinbingChenGuohaoShi
THE JOURNAL OF BIOMEDICAL RESEARCH 2011年2期

Liang Zong, Ping Chen, Yinbing Chen, Guohao Shi

Department of Gastrointestinal Surgery, Subei People’s Hospital of Jiangsu Province, Yangzhou, Jiangsu 225001, China

INTRODUCTION

Gastric cancer is the second most common malignancy in the world, and surgical resection remains the only curative treatment option. A patient with total gastric resection may undergo various reconstructions[1-5]. The method of choice for reconstruction after total gastrectomy for gastric carcinoma still remains controversial. It is well known that, worldwide, the addition of a pouch is only performed in some highly selective large cancer centers. Till now, several studies on this topic have failed to reach a consensus that Roux-en-Y reconstruction with a pouch is a technique of choice. However, Roux-en-Y esophagojejunostomy with a pouch is still considered to be associated with a high incidence of postoperative complications after distal gastrectomy regardless of its main advantage of improving quality of life. In addition, Roux-en-Y esophagojejunostomy with a pouch seems to be highly individual decisions, sometimes by a surgeon’s lack of persuasive or objective evidence. The aim of this report was to review all the currently available evidence and derive a more precise estimation of Roux-en-Y esophagojejunostomy with a pouch compared with Roux-en-Y esophagojejunostomy without a pouch by making a systematic analysis. Therefore, data on total postoperative complications, anastomic leakage,mortality, 5-year survival, reflux symptoms, dumping syndrome, reflux esophagitis, eating capacity, serum albumin, quality of life index, operation time, blood loss and hospital stay were extracted to make a metaanalysis on "pouch Roux-en-Y vs. no pouch Rouxen-Y" after total gastrectomy.

MATERIALS AND METHODS

The entire process of study selection, data analysis,and presentation of results was executed in accordance with the Quality of Reporting Meta-Analysis(QUOROM) statement[6]to ensure the highest quality of this meta-analysis.

Publication search

Two electronic databases (PubMed and Embase)were searched (last search was updated on 15 October 2010, using the search terms: "total gastrectomy","gastric cancer" and "reconstruction"). All eligible studies were retrieved, and their bibliographies were checked for other relevant publications. Review articles and bibliographies of other relevant studies identified were hand-searched to find additional eligible studies. Only published studies with full-text articles were included. When more than one of the same patient population was included in several publications,only the most recent or complete study was used in this meta-analysis.

Inclusion criteria

The inclusion criteria were as follows: 1) the study addressed the question whether the value of Rouxen-Y esophagojejunostomy with a pouch as a gastric substitute after total gastrectomy was assessed in comparison with Roux-en-Y esophagojejunostomy without a pouch; 2) the study was a clinical trial study;3) the study contained sufficient data for estimating the odds ratio (OR) with 95% confidence interval (CI).

Data extraction

Information was carefully extracted and assessed by two of the authors from all eligible studies. Each of the publications was identified independently. The following data were collected from each study: first author’s surname, publication date, study design, patient numbers, length of follow-up, main results and conclusions. Data was included for analysis when at least two randomized control trials (RCTs) analyzed the same specific parameter. We did not define a limit on the minimum number of patients to include a study in our meta-analysis.

Statistical methods

Comparisons of binary outcome measurements(e.g., complication and the incidence of reflux symptom) among reconstruction techniques were provided by pooled estimates of OR with 95%CI. Effects on quantitative measurements (e.g., length of hospital stay) were analyzed by the weighted mean difference(WMD) approach. Heterogeneity assumption was checked by the χ2-based q test. P-value greater than 0.10 for the q test indicates a lack of heterogeneity among studies, so the OR or WMD estimate of each study was calculated by the fixed-effects model (the Mantel-Haenszel method). Otherwise, the randomeffects model (the DerSimonian and Laird method)was used[7]. Statistical significance was determined by the z test and P > 0.05 was considered as statistically significant. Sensitivity analyses were carried out to check if modification of the inclusion criteria of this meta-analysis affected the final results. An estimate of potential publication bias was carried out by the funnel plot. An asymmetric plot suggests a possible publication bias. Funnel plot asymmetry was assessed by the method of Egger’s linear regression test, a linear regression approach to measure funnel plot asymmetry on the natural logarithm scale of the OR or WMD.The significance of the intercept was determined by the t-test, suggested by Egger (P < 0.05 was considered representative of statistically significant publication bias). All the statistical tests were performed with Review Manager Version 4.2 (The Cochrane Collaboration, Oxford, England).

RESULTS

Study characteristics

Overall, 30 reports of RCTs comparing Roux-en-Y reconstruction with a pouch and Roux-en-Y reconstructions without a pouch after total gastrectomy for gastric malignancies, published between 1987 and 2010, were found. However, several publications reported on the same trial and the same patient groups differing only in sample size, length of follow-up, or subgroup analysis. Regardless of these partially duplicated reports, a total of 15 independent RCTs could be identified. Three RCTs were excluded, as they did not analyze the parameters for which we sought to analyze(e.g., postoperative complications or the incidence of reflux symptoms or esophagitis or gastritisl), but rather compared cholecystokinin, bacterial counts and total bile acid concentrations over 24 h[8-10]. The remaining 12 RCTs, however, of which 2 duplicated RCTs were still included due to the analysis of different and uncorrelated parameters[22,23], were used to evaluate the value of Roux-en-Y reconstruction with or without a pouch after total gastrectomy. Twelve trials, including 1018 patients, met the inclusion criteria. Of the 12 trials, sample sizes ranged from 20 to 271. The main results of these 12 trials are listed in Tables 1 and 2. According to the Cochrane risk of bias tool, all the metaanalyses included only trials with low risk of bias.

Meta-analysis results

The results on either total postoperative complications or anastomotic leakage indicate that there was no significant difference between pouch Roux-en-Y reconstruction and simple Roux-en-Y construction(OR=1.40, 95% CI=0.96-2.03; P = 0.08, Pheterogeneity= 0.78 and OR=1.73, 95% CI=0.78-3.85; P = 0.18, Pheterogeneity= 0.61, shown in Fig. 1A and 1B). The meta-analysis on mortality shows that pouch Roux-en-Y reconstruction does not carry significant additional mortality(OR=1.05, 95% CI=0.43-2.55; P = 0.91, Pheterogeneity=0.97, shown in Fig.1C). Similarly, the meta-analysis on 5-year survival showed no significant differences between them (OR=1.09, 95% CI=0.68-1.77; P = 0.72,Pheterogeneity= 0.64, shown in Fig. 1D). Based on the results above, we concluded that pouch Roux-en-Y reconstruction did not relevantly or statistically increase total postoperative complications or anastomosis leakage or mortality compared with no simple Roux-en-Y reconstruction. Moreover, both of them are similar in 5-year survival rate. Meta-analyses carried out for postoperative reflux symptoms, dumping syndrome and reflux esophagitis were performed. Using these parameters, the analyses revealed that pouch Roux-en-Y reconstruction did not reduce the incidence of reflux symptoms or esophagitis, but improved dumping syndrome significantly compared with simple Rouxen-Y reconstruction (OR=0.60, 95% CI=0.27-1.35;P = 0.22, Pheterogeneity= 0.22; OR=0.32, 95% CI=0.11-0.87; P = 0.03, Pheterogeneity= 0.97 and OR=1.10, 95%CI=0.30-4.09; P = 0.89, Pheterogeneity= 0.41, respectively, shown in Fig. 2A to 2C). The patients with a pouch reservoir had a better eating capacity than patients without a pouch reservoir (WMD=4.46, 95 %CI=1.73-11.52; P = 0.002, Pheterogeneity= 0.004, Fig. 2D).Still, in terms of short-term nutrition, there was no difference in serum albumin content between the twogroups (WMD=-0.29, 95 % CI=-1.18-0.61; P = 0.53,Pheterogeneity= 0.2, Fig. 2E). Meta-analysis showed an improved quality of life in patients who underwent pouch Roux-en-Y reconstruction (WMD=9.54, 95 % CI=7.35-11.73; P < 0.001, Pheterogeneity= 0.23, Fig. 2F). As for intra-operative data, operation time and blood loss,our meta-analyses report significantly less time but no lower blood loss in simple Roux-en-Y reconstruction than pouch Roux-en-Y reconstruction (WMD=27.75,95% CI=23.81-31.70; P < 0.00001, Pheterogeneity= 0.09 and WMD=96.48, 95% CI=-90.04-281.00; p = 0.31,Pheterogeneity< 0.00001, respectively, Fig. 3A and 3B).Further more, a significantly shorter hospital stay was associated with patients who underwent pouch Rouxen-Y reconstruction opposed to simple Roux-en-Y reconstruction (WMD=-3.01, 95% CI=-3.41--2.62; P< 0.001, Pheterogeneity= 0.34, Fig. 3C)

Table 1 Main characteristics of studies included

Table 2 Main Characteristics of studies included (continued)

Publication bias

Begg’s funnel plot was performed to access the publication bias of the retrieved literature (Fig. 4).

DISCUSSION

Surgical treatment plays a predominant role in the management of patients with gastric carcinoma. Total gastrectomy is the most common surgical procedure,which can achieve adequate safety margins in relation to the tumor to offer patients a chance of cure.Various reconstructive procedures can be chosen after total gastrectomy. In Japan, as well as in many other countries, the Roux-en-Y esophagojejunostomy is the preferred reconstruction after total gastrectomy as it is relatively simple to perform and prevents reflux esophagitis. Still, according to some published studies, simple Roux-en-Y construction is not satisfactory with regard to dietary intake, nutrition and quality of life. However, pouch Roux-en-Y reconstruction may provide better dietary intake, nutrition and quality of life in short-term or long-term periods. This alternative has been emphasized as having advantages such as 1) production of the pseudopyloric function to slow the progress of ingested food from a reservoir into the small intestine and reduce the distressing symptoms of the dumping syndrome; 2) provision of a reservoir for digestion and absorption; 3) lessened requirement of frequent meals. Moreover, pouch Roux-en-Y reconstruction may also result in less bile reflux into the esophagus as compared to Roux-en-Y reconstruction.The comparable disadvantages of pouch Roux-en-Y reconstruction include complexity in surgical proce-dure and the possible development of postoperative complications, especially anastomotic leakage and overall mortality. The potential cause may be additional anastomosis needed to construct. Therefore,Roux-en-Y reconstruction with or without pouch can only be selected by considering the advantages and disadvantages. Supposed that pouch Roux-en-Y reconstruction could be modified to reduce the incidence of postoperative complications and mortality,this procedure would be more strongly recommended for reconstruction after a total gastrectomy. Interestingly, in recent years, with the wide application of the surgical stapler, several studies have found that postoperative complications of pouch Roux-en-Y reconstruction have significantly decreased[24]. Some also argue that this may be the result of improved experience of surgeons. Under this situation, several studies have been designed to provide convincing results to define the optimal reconstruction technique between pouch Roux-en-Y and simple Roux-en-Y for patients necessitating total gastrectomy[8-20]. However, the results present no generally accepted consensus, or even absolute opposite opinions. This is partly due to lack of formal meta-analyses and the heterogeneity of reconstruction techniques included in these reviews.

Fig. 1 Meta-analyses of parameters of the postoperative course. A: Total postoperative complications. B: Anastomotic leakage. C: Mortality. D: 5-year survival.

Fig. 2 Meta-analyses of parameters of the quality of life. A: Reflux symptoms. B: Dumping syndrome. C: Reflux esophagitis. D: Eating capacity. E: Serum albumin. F: Quality of life index.

Fig. 3 Meta-analyses of parameters of general data of operation. A: Operation time. B: Blood loss. C: Hospital stay.

The main objective of surgery for patients suffering from malignant diseases, on the one hand, is to prolong survival time with fewer postoperative complications, and, on the other hand, is to supply a high quality of life in their remaining lifetime. Thus, to make an objective evaluation of surgical procedure,operative parameters such as total postoperative complications, anastomotic leakage, mortality and 5-year survival were collected for comparison in our study.As to postoperative quality of life parameters, reflux symptoms, dumping syndrome, eating capacity, nutrition index and quality of life index were selected from RCTs.

Our meta-analyses indicate no significance in postoperative complications, anastomotic leakage, mortality and 5-year survival between the two procedures.However, pouch Roux-en-Y reconstruction is superior in reducing dumping syndrome and improving food intake. Statistically significant differences are mainly due to the active function of the pouch reservoir. As for reflux symptoms, pouch Roux-en-Y reconstruction is not associated with a lower incidence than simple Roux-en-Y reconstruction because both can play a role in anti-esophageal reflux. The original purpose of Moynihan-type procedure was to reduce the incidence of reflux esophagitis by means of Braun anastomosis.In both simple Roux-en-Y and pouch Roux-en-Y reconstruction, with a 40 to 50 cm distance between the esophagus and the Roux-en-Y anastomosis, the interposed jejunual "Y" limb can prevent esophageal damage from alkaline intestinal secretions. Thus, both the pouch and simple Roux-en-Y reconstruction methods can decrease reflux symptoms and reflux esophagitis.

Fig. 4 The publieation bias of the retrived literature (Pouch Roux-en-Y vs No Pouch) A: Postoperative complications. B: Anastomotic leakage. C: Mortalty. D: 5-year survival. E: Reflux symptom. F: Dumping syndrome. G: Rellux esophagitie. H: Eating capacity in normal size. I: Serum Albumin. J: Quality of Life Index. K: Operation time. L: Blood loss. M: Hospital stay.

Finally, serum albumin was measured as a postoperative nutrition parameter. There was no significant difference between pouch Roux-en-Y reconstruction and simple Roux-en-Y reconstruction in the short term postoperatively. That may be explained by total food intake balance. Specifically, when patients with simple Roux-en-Y reconstruction eat less food per meal, they can increase the frequency of daily meals to get an equal total nutrient intake. As a consequence, reduced postoperative complaints and better food intake can extremely improve the patients’ quality of life. Furthermore, quality of life index of patients with Rouxen-Y reconstruction reached statistical significance compared with that of patients with simple Roux-en-Y reconstruction during short-term follow-up postoperatively. In our meta-analyses, we also collected and analyzed intra-operative parameters, such as operation time and blood loss, which may correlate with the experience of the surgeon. Because of the wide variation of surgeons’ experience and unclear risk of bias, this result showed extreme heterogeneity and a significant difference between the two groups. In other words,pouch Roux-en-Y reconstruction prolongs the operation time without increasing blood loss. Nevertheless,pouch Roux-en-Y reconstruction has been shown to offer patients a reduced length of hospital stay. Possible causes of this finding revealed that the pouch not only reduces the postoperative symptoms, but also contributes to faster postoperative recovery of gastrointestinal function. Moreover, the pouch did not carry additional complications. Overall, each metaanalysis itself, however, also contains several possible shortcomings and bias to be considered[25,26]. Our meta-analyses prove that Roux-en-Y reconstruction integrated with a pouch after total gastrectomy tends to be a gastric substitute. Finally, we want to emphasize that not only complete oncological resection for cure but also quality of life should be considered in the decision on reconstruction choice.

Owing to the reason of small sample size and potential heterogeneity, it limits us to reach a more precise conclusion. Another meta-analysis on pouch adding reached a similar conclusion to ours[27]. However,a larger number of patients for RCT are required to obtain statistically significant results.

Reference

[1] Lawrence WJr. Reservoir construction after total gastrectomy: an instructive case. Ann Surg 1962;155:191-8.

[2] Longmire WP, Beal JM. Construction of a substitute gastric reservoir following total gastrectomy. Ann Surg 1952;135:637.

[3] El Halabi HM, Lawrence WJr. Clinical results of various reconstructions employed after total gastrectomy. J Surg Oncol 2008;97:186-92.

[4] Lehnert T, Buhl K. Techniques of reconstruction at er total gastrectomy for cancer. Br J Surg 2004;91:528-39.

[5] Chin AC, Espat NJ. Total gastrectomy: options for the restoration of gastrointestinal continuity. Lancet Oncol 2003;4:1-10.

[6] Moher D, Cook DJ, Eastwood S, Olkin I, Rennie D,Stroup DF. Improving the quality of reports of metaanalyses of randomised controlled trials: the QUOROM statement. Quality of Reporting of Meta-analyses. Lancet 1999;354:1896-900.

[7] DerSimonian R, Laird N. Meta-analysis in clinical trials.Control Clin Trials 1986;7:177-88.

[8] Zilling T, Hansson L, Willén R, Sternby B. Nutritional state, growth rate, and morphology after total gastrectomy with restoration of duodenal passage or Roux-en-Y oesophagojejunostomy with or without a pouch: an experimental study in pigs. Eur J Surg 1998;164:377-84.

[9] Iivonen MK, Ahola TO, Matikainen MJ. Bacterial overgrowth, intestinal transit, and nutrition after total gastrectomy. Comparison of a jejunal pouch with Roux-en-Y reconstruction in a prospective random study. Scand J Gastroenterol 1998;33:63-70.

[10] Mon RA, Cullen JJ. Standard Roux-en-Y gastrojejunostomy vs. "uncut" Roux-en-Y gastrojejunostomy: a matched cohort study. J Gastrointest Surg 2000;4:298-303.

[11] Wei HB, Wei B, Zheng ZH, Zheng F, Qiu WS, Guo WP,etal.Comparative Study on Three Types of Alimentary Reconstruction After Total Gastrectomy. J Gastrointest Surg 2008;12:1376-82.

[12] Fein M, Fuchs KH, Thalheimer A, Freys SM, Heimbucher J, Thiede A. Long-Term Benefits of Roux-en-Y Pouch Reconstruction After Total Gastrectomy A Randomized Trial. Ann Surg 2008;247:759-65.

[13] Kalmár K, Cseke L, Zámbó K, Horváth OP.Comparison of Quality of Life and Nutritional Parameters After Total Gastrectomy and a New Type of Pouch Construction with Simple Roux-en-Y Reconstruction. Dig Dis Sci 2001;46:1791-6.

[14] Fuchs KH, Thiede A, Engemann R, Deltz E, Stremme O, Hamelmann H. Reconstruction of the food passage after total gastrectomy: randomized trial. World J Surg 1995;19:698-706.

[15] Hirao M, Kurokawa Y, Fujitani K, Tsujinaka T. Randomized Controlled Trial of Roux-en-Y Versus Rho-Shaped-Roux-en-Y Reconstruction After Distal Gastrectomy for Gastric Cancer. World J Surg 2009;33:290-5.

[16] Bozzetti F, Bonfanti G, Castellani R, Maffioli L, Rubino A, Diazzi G, et al. Comparing reconstruction with Rouxen-Y to a pouch following total gastrectomy. J Am Coll Surg 1996;183:243-8.

[17] Paimela H, Ketola S, Iivonen M, Tomminen T, Könönen E, Oksala N, et al. Long-Term Results After Surgery for Gastric Cancer with or without Jejunal Reservoir. Int J Gastrointest Cancer 2005;36:147-53.

[18] Nozoe T, Anai H, Sugimachi K. Usefulness of reconstruction with jejunal pouch in total gastrectomy for gastric cancer in early improvement of nutritional condition. Am J Surg 2001;181:274-8.

[19] Adachi S, Inagawa S, Enomoto T, Shinozaki E, Oda T,Kawamoto T. Subjective and functional results after total gastrectomy: prospective study for longterm comparison of reconstruction procedures. Gastric Cancer 2003;6:24-9.

[20] Kono K, Iizuka H, Sekikawa T, Sugai H, Takahashi A, Fujii H, et al. Improved quality of life with jejunal pouch reconstruction after total gastrectomy. Am J Surg 2003;185:150-4.

[21] Nakane Y, Okumura S, Akehira K, Okamura S, Boku T,Okusa T, et al. Jejunal pouch reconstruction after total gastrectomy for cancer. Ann Surg 1995;222:27-35.

[22] Iivonen MK, Koskinen MO, Ikonen TJ, Matikainen MJ.Emptying of the jejunal pouch and Roux-en-Y limb after total gastrectomy--a randomised, prospective study. Eur J Surg 1999;165:742-7.

[23] Iivonen MK, Mattila JJ, Nordback IH, Matikainen MJ.Long-term follow-up of patients with jejunalpouch reconstruction after total gastrectomy. A randomized prospective study. Scand J Gastroenterol 2000;35:679-85.

[24] Chua CL. Total gastrectomy for gastric cancer: the rationale for J-pouch reservoir. J R Coll Surg Edinb 1998;43:169-73.

[25] Murray. Meta-analysis. Br J Surg 1990;77:243-4.

[26] Yusuf S. Meta-analysis of randomized trials: looking back and looking ahead. Control Clin Trials 1997;18:594-601.

[27] Gertler R, Rosenberg R, Feith M, Schuster T, Friess H.Pouch vs. No Pouch Following Total Gastrectomy: Meta-Analysis and Systematic Review. Am J Gastroenterol 2009;104:2838-51.