AIM: To investigate the feasibility, advantages and disadvantages of two types of anvil insertion techniques for esophagojejunostomy after laparoscopic total gastrectomy.

METHODS: This was an open-label prospective cohort study. Laparoscopy-assisted radical total gastrectomy with D2 lymph node dissection was performed in 84 patients with primary non-metastatic gastric cancer confirmed by pre-operative histological examination. Overweight patients were excluded, as well as patients with peritoneal dissemination and invasion of adjacent organs. After total gastrectomy, all patients were randomized into two groups. Patients in Group I underwent esophagojejunostomy using a transorally-inserted anvil (OrVil^TM), while patients in Group II underwent esophagojejunostomy using the hemi-double stapling technique (HDST). Both types of esophagojejunostomy were performed under laparoscopy. Patients’ baseline characteristics, preoperative characteristics, perioperative characteristics, short-term postoperative outcomes and operation cost were compared between the two groups. The primary endpoint was evaluation of the surgical outcome (operating time, time of digestive tract reconstruction and time of anvil insertion) and the medical cost of each operation (operation cost and total cost of hospitalization). The secondary endpoints were time to solid diet, post-surgical hospitalization time, time to defecation, time to ambulation and intra-operative blood loss. In addition, complications were assessed and compared.

RESULTS: Laparoscopic total gastrectomy and esophagojejunostomy were successfully performed in all 84 patients, without conversion to laparotomy. There were no significant differences in the operative time and time for total gastrectomy between the two groups (287.8 ± 38.4 min vs 271.8 ± 46.1 min, P = 0.09, and 147.7 ± 31.6 min vs 159.8 ± 33.8 min, P = 0.09, respectively). The time for digestive tract reconstruction and for anvil insertion were significantly decreased in Group II compared with Group I (47.8 ± 12.1 min vs 55.4 ± 15.7 min, P = 0.01, and 12.6 ± 4.7 min vs 18.7 ± 7.5 min, P = 0.001, respectively). Intra-operative blood loss (96.4 ± 32.7 mL vs 88.2 ± 36.9 mL, P = 0.28), time to defecation (3.5 ± 0.9 d vs 3.2 ± 1.1 d, P = 0.12), time to ambulation (3.9 ± 0.7 d vs 3.6 ± 1.1 d, P = 0.12), time to solid diet (7.6 ± 1.4 d vs 8.0 ± 2.7 d, P = 0.31) and total hospitalization (10.6 ± 2.6 d vs 10.8 ± 3.5 d, P = 0.80) were similar between the two groups. In addition, the total costs of hospitalization were similar between the two groups (73848.7 ± 11781.0 RMB vs 70870.3 ± 14003.5 RMB, P = 0.296), but operation cost was significantly higher in Group I compared with Group II (32401.9 ± 1981.6 RMB vs 26961.9 ± 2293.8 RMB, P < 0.001).

CONCLUSION: Anvil insertion was faster and easier using the HDST technique compared with OrVil^TM, and was more cost-effective. There was no significant difference in safety.

Surgery is the main treatment for gastric cancer[1]. Laparoscopy-assisted radical gastrectomy for gastric cancer has been used for more than 20 years[2]. The improvement of these techniques and apparatus have led to a gradual expansion of the available laparoscopy-assisted surgical methods for gastric cancer, allowing a more complete dissection of lymph nodes[3,4]. However, there are still some technical issues, and reconstruction of the digestive tract after total gastrectomy is one of these.

Delayed development of laparoscopic total gastrectomy is mainly attributed to the high technical requirements for laparoscopic esophagojejunostomy. Currently, many methods are available for reconstruction of the digestive tract after total gastrectomy[5-7]. An upper vertical midline incision with a length of about 5-7 cm in the abdominal wall is usually used to perform esophagojejunostomy after laparoscopic total gastrectomy. The length of the incision might even reach 8-11 cm in some obese patients, resulting in a more invasive treatment[8]. Side-to-side esophagojejunal anastomosis has been used for many years. This method has a large anastomotic diameter and anastomotic stricture is not easy to perform after surgery, but could solve some problems of esophagojejunostomy[7,9,10]. End-to-side esophagojejunal anastomosis is still a widely used anastomotic method[11]. However, some procedures are very difficult to perform, such as placement of the stapler anvil on the esophageal stump. If an open operation is performed, the first step of this process is to perform a purse-string suture of the lower edge of the esophagus. However, this procedure is difficult under laparoscopy, and could easily lead to potential problems in the operation, failure in anastomosis and prolonged surgery.

Many methods have been suggested for improving the placement of anvils under laparoscopy[12-15]; however, there is no consensus about their use. Currently, the major methods of anvil insertion involve transoral and intra-abdominal placements. The transorally-inserted anvil (OrVil^TM)[16] and the hemi-double stapling technique (HDST)[17] were recently developed. Although these two techniques have only been used for a short period, they have attracted much attention because they are simple and omit the need for a purse-string suture of the esophagus[18-21]. The OrVil^TM technique inserts the stapler anvil through a transoral esophageal approach. A tube is connected with the central rod of the stapler. The tube is inserted in the esophagus and pulled out from the esophageal stump, and the anvil is placed under the guide of the tube. In the HDST method, the anvil is inserted through the lower esophagus, and the needles and threads are pulled out from the anterior wall of the esophagus. Subsequently, the lower esophagus is closed, and finally, the anvil is pulled out from the anterior wall close to the esophageal stump guided by the needles and threads, thereby completing the anvil insertion. In this technique, the anvil is inserted in a lower-upper pattern, and purse-string suturing is not required. These two methods are skillfully designed, simple and practical, and they can be completely mastered after simple training. However, it is not clear which of these methods is the best one.

Therefore, this study used either OrVil^TM or HDST anvil insertion methods to perform esophagojejunostomy after laparoscopic total gastrectomy and compared the effectiveness of these two methods in an open-label prospective cohort study. The results should provide important information on selection of the best method for anvil insertion for esopagojejunostomy in the clinical practice.

The aim of the present trial was to compare two different methods of anvil insertion for esophagojejunostomy after laparoscopic total gastrectomy, primarily in terms of surgical difficulty. All procedures were successfully completed during the 84 total gastrectomy surgeries in patients with gastric cancer. In addition, no technical problems occurred in any case during the reconstruction of the digestive tract and none of the cases needed conversion to laparotomy or expansion of the surgical incision, indicating that these two methods had a high reliability and stability.

Novel methods have been introduced for esophagojejunostomy because of the technical difficulties of this procedure in a laparoscopic setting. Purse-string suturing is a difficult technique to perform in a narrow space with a restricted view, which requires experience and skill from the surgeon. When purse-string suturing is required, a lot of surgical time is consumed. Therefore, most surgeons are reluctant to perform such procedures. Both the OrVil^TM system[22-24] and HDST[25,26] have been shown to simplify esophagojejunostomy, with high success rates and few requirements for transfer to laparotomy. To our knowledge this is the first randomized study to compare these two methods after total gastrectomy, although one previous study compared these methods on a smaller cohort alongside a conventional anvil head method and side-to-side esophagojejunostomy with a linear stapler[21]. That study showed that surgery with OrVil^TM was similar in time course to a more traditional method and concluded that none of the methods tested were entirely satisfactory. In the present study, the mean time of digestive tract anastomosis was 55.4 min using the OrVil^TM system and 47.8 min using the HDST technique. In addition, the mean time for stapler anvil insertion was 18.7 min using the OrVil^TM technique and 12.6 min using the HDST technique. Both of these techniques completed anvil insertion in a short time period, indicating that they were simple and easy to perform. Anvil insertion using the OrVil^TM technique took a longer time than the HDST technique, which might be attributed to transoral placement procedures. In addition, the flexible tube operated by the anesthesiologist was difficult to control. In order to enable the head of the tube to be fixed in a good position, repeated adjustment was required that led to a longer operation time. However, due to omission of purse-string suturing, these two methods exhibited a significant superiority over the traditional purse-string suture methods in terms of the time of operation, which in our experience take approximately 20-25 min longer.

An important factor in survival after total gastrectomy is achieving a negative surgical margin. This is influenced by a number of factors, but most importantly the extent of the tumor and the extent of surgery[27]. The mean distance between the surgical margin on the proximal esophagus and the tumor is an important marker for a negative surgical margin[28]. If an open operation is performed, the surgical margin of the esophagus can reach 3-5 cm superior to the cardia. In the present study, among the 56 cases with carcinoma involving the gastric cardia, the mean distance between the surgical margin on the proximal esophagus and the cancer was about 3 cm, and no residual cancer tissues were observed, which ensured the completion of tumor resection.

Comparison of open and laparoscopic techniques for total gastrectomy suggests that these methods have similar outcome and success rates, but laparoscopic total gastrectomy can be associated with an increased complication rates in comparison with open surgery[29]. The most common of these complications is an anastomotic fistula, although recent laparoscopic methods have shown decreased rates as the techniques have improved[30]. Of the 84 patients who underwent esophagojejunostomy, anastomotic fistula occurred in only one case from Group II. This case was diagnosed as esophageal-jejunal anastomotic micro-fistula using radiographic examination and was cured with post-surgical drainage and enteral nutrition. If anastomosis is unsatisfactory, it is suggested that the suture be strengthened and the drainage tube be routinely indwelled beside the anastomotic stoma. Radiographic examinations should be performed in some suspected patients prior to removal of the drainage tube in order to exclude anastomotic fistula.

Anastomotic stenosis is another complication commonly observed in patients after undergoing laparoscopic total gastrectomy. In the present study, 4 out of 84 patients developed anastomotic stenosis. Shim et al[21] reported that anastomic stenosis occurred in 5 out of 26 patients after esophagojejunostomy using the OrVil^TM and HDST techniques. Umemura et al[31] reported that the incidence of stenosis after esophagojejunostomy using a linear stapler was only 1.8%. Therefore, we suggest that the incidence of anastomotic stenosis after esophagojejunostomy using circular stapler methods was higher than that using a linear stapler. However, further study is necessary to address this issue.

Based on previous reports, some surgeons have made several modifications to these two surgical methods with the aim of overcoming the corresponding shortcomings. Indeed, the OrVil^TM technique often results in a dog ear, and Hirahara et al[26] tried to solve this issue with a loop-shaped thread wrapped around the esophageal stump opening. With this modification, esophagojejunostomy was completed without a dog-ear. This approach may decrease the incidence of anastomotic fistula, but studies with larger sample size are required to support this assertion due to the small number of cases in this study. Muguruma et al[19] described a similar technique based on the procedure described by Omori et al[17], except that they used the OrVil^TM anvil instead of the ECS25 (Ethicon Endo-Surgery stapler). It was found that the OrVil^TM anvil was much easier to use and that surgeons with relatively little experience in gastric laparoscopy were able to conduct the operation and avoid complications. The median operative time was 318 min including 5 min for the placement of the anvil on the esophageal stump. Compared with these two retrospective studies, the present study focused on the prospective comparison between the two methods. We believe that these two methods for esophagojejunostomy will gain an increasing recognition, and will be widely used by more and more surgeons.

Compared with the HDST technique, the OrVil^TM system requires a specific stapler and has a higher cost, while the HDST technique does not need a specific stapler and has a relatively low cost. Therefore, the use of the HDST technique might be more practical in undeveloped areas of the world.

The present study has some limitations. As the main purpose of the study was to evaluate two different methods of anvil insertion for esophagojejunostomy, we did not collect detailed data on tumor differentiation status, since these would not generally impact upon the surgical difficulty. If these data had been collected, a more detailed comparison between the groups and long-term outcomes could be performed. A larger multicenter study would also add more data and provide more convincing evidence for the most suitable anvil insertion method. A longer follow-up period would provide more information on the long-term effects of surgery and should be considered in future studies.

In summary, we conclude that the OrVil^TM and HDST techniques were simple and reliable without any significant differences in safety and difficulty of operation. Both were reliable techniques for laparoscopic esophagojejunostomy.