Laparoscopic gastrectomy has become the common operation for gastric cancer worldwide. For early upper gastric cancer, several random controlled trials (RCTs) including JCOG1401, KLASS-03 and CLASS-02 have demonstrated that LATG is safe and feasible[12–14]. Thus, LATG has been established as one of the standard surgical procedures according to Japanese Gastric Cancer Treatment Guideline 2018 (5th edition). Since Goh et al. firstly reported the intracorporeal gastrojejunostomy with the linear stapler, totally laparoscopic total gastrectomy (TLTG) has been more and more widely accepted. Kanaji et al. believed that TLTG was associated with shorter hospital stay, smaller incision, adequate working space and faster postoperative recovery through a comparative analysis of 114 patients. These results may be due to intraoperative refinement and field enlargement during anastomosis. However, totally laparoscopic esophagojejunostomy is still a big challenge for surgeons.
At present, the circular and linear staplers are used for reconstruction after TLTG. Most previous comparative studies between TLTG and LATG were mainly based on data by using circular stapler. TLTG with circular stapler may cause postoperative anastomotic stenosis. Compared with circular stapler, linear stapler has the advantages of no purse-string suture, larger anastomotic diameter, and no limitation of esophagus and small intestine diameter. In addition, intracorporeal esophagojejunostomy is normally performed in a narrow space, and the reconstruction can be achieved more easily by linear stapler[29, 30]. Nowadays, TLTG with linear anastomosis mainly includes overlap anastomosis, π-shaped anastomosis and functional end-to-end anastomosis (FEEA). Through a retrospective analysis of 113 patients, Kim et al. concluded that totally laparoscopic anastomosis by linear stapler was the best procedure for esophagogastric junction tumors in overweight patients. Similarly, Wang et al. confirmed the safety and feasibility of TLTG (overlap reconstruction) in advanced Siewert III esophagogastric junction cancer and the upper and middle third of gastric cancer by a prospective, single-center, single-blind, two-arm randomized controlled trial. However, few comparative studies between TLTG with linear stapler and LATG have been reported. Therefore, we retrospectively analyzed the results of patients received the TLTG with linear stapler(overlap and π-shaped method)in our center to determine the advantage of this method. For more, we also meta-analyzed all of the available studies that compared LATG and TLTG with linear stapler, which resulted in 6 nonrandomized controlled studies (NRS).
Our results demonstrated the estimated blood loss, the length of incision and the administration of analgesics in TLTG group were less than those in LATG group. The result of less blood loss was also supported by meta-analysis. In LATG group, more blood loss might be caused by the larger skin incision and anastomosis by hand though the incision. The administration of analgesics was used to evaluate the postoperative pain, and less pain in TLTG group is most likely due to the shorter incision. There were no statistically differences among the number of harvested lymph nodes, start of liquid diet, start of soft diet, extubating time and postoperative hospital stay between two groups. However, the result of meta-analysis revealed that TLTG group was associated with more harvested lymph nodes. Because the lymph nodes dissection was performed by laparoscopy in both groups, there should be no difference in number of harvested lymph nodes. Then we checked the data and found that the data from Gong et al. contributed a lot to the result of meta-analysis. The author didn’t explain the reason and also confessed that the lymphadenectomy procedure was the same. The safety of operation is an important factor focused by surgeons. In our research, 12 patients (11.11%) in TLTG group and 18 patients (11.76%) in LATG group suffered from postoperative complications. However, there was still 9 patients experienced anastomotic leakage in our study which was diagnosed by CT examination. Through conservative treatment such as CT-guided puncture and drainage, anti-infection, and enteral nutrition tube placement, the patients recovered uneventfully. There were no significant differences on complications between two groups, which was similar with the results of meta-analysis. Therefore, the rate of the complications related to anastomosis was 6.25% with no significant difference by data of our center or meta-analysis.
In TLTG, Inaba firstly developed a side-to-side anastomosis called “overlap”, which has several advantages including a change in the direction of the jejunal limb to alleviate tension at the anastomosis. Huang et al. summarized the clinicopathological data of 507 patients received TLTG with overlap anastomosis or LATG and revealed that overlap anastomosis could reduce blood loss, pain and dysphagia, thus improving postoperative quality of life. Although, the overlap method was reported as a safe and useful technique, there are still technical difficulties in this procedure. It is difficult to insert linear stapler into the short esophageal stump. And it requires advanced suturing skills to close the common incision after anastomosis in a narrow and deep field[34, 35]. In our study, compared with LATG group, the group of TLTG-overlap showed favorable surgical outcomes of less blood loss, shorter incision length and less uses of analgesics. But overlap method was associated with more operative time, which may be due to the difficulty in suturing.
Another novel operative technique called π-shaped method was reported as an easy and effective option for TLTG. In this method, gastric resection, jejunal division and common hole closure were integrated into one procedure. The difficulty of hand-sewn sutures and traction of the esophagus were solved by this method. Through a retrospective analysis of 143 patients, Chen et al. concluded that totally laparoscopic anastomosis with π-shaped anastomosis was safe and feasible. In our study, we found that traction of the esophagus was easier, which could provide the maximum visual operating space, and the 3-in-1 procedure really simplified the anastomosis procedures. Therefore, in our study, the operative time was significantly reduced in TLTG-π group, and the trend was also observed even after PSM. The TLTG-π group also exhibited less blood loss, more harvested lymph nodes, shorter incision length and less administration of analgesics compared with LATG group. However, the surgeons could only check the proximal margin after completion of the anastomosis. If the tumor invaded the margin, it would be a disaster. Therefore, according to our experiences, π-shaped method is recommended for patients with the upper edge of tumor below the Zigzag line. And it’s also very important for the surgeons to identify the location of the tumor by gastroscopy and CT scan before surgery.
In our research, compared π-shaped method with overlap method, we found that πgroup showed shorter operative time, more harvested lymph nodes and faster postoperative diet. After esophagojejunostomy, it’s easier for π-shaped method to close the common incision by a linear stapler, and the operative time is reduced. In this study, more cases in π-shaped group were operated on 3D laparoscopy, and several studies reported that 3D laparoscopy can harvest more lymph nodes than 2D laparoscopy[38–42]. That might be the reason for the difference in number of dissected lymph nodes. Because the number of patients involved in overlap group is relatively small, more cases are still needed to validate the differences between these two methods and the immature technology at that time.
There are several limitations to our studies. First, it was retrospective and the number of cases included was relatively not enough. Some selection biases might exist. Second, it was performed at a single center in China, where the average BMI is lower than a common Western BMI. Thus, our results may not be applicable to Western people. Third, 2D or 3D laparoscopy was used in this study, that might influence the results. Fourth, although there are several different linear anastomosis methods, our center only included patients with overlap and π-shaped anastomosis.