Due to its obvious advantages over traditional gastrectomy, the number of patients undergoing LDG is rapidly increasing, especially in eastern Asia, where gastric cancer is one of the most common malignancies. The purpose of LDG in gastric cancer patients is to meet oncologic demands and not affect survival by minimizing operative insults.
However, the use of LDG in gastric cancer has not yet met with widespread acceptance because of the lack of evidence regarding the oncological adequacy of laparoscopic procedures and the long-term results . Opinions still differ as to whether it can achieve the same effect in D2 lymphadenectomy as open surgery and whether the procedure is safe. It is well known that the adequacy of radical resection should be evaluated by the extent of lymph node dissection performed as well as the number of retrieved lymph nodes (RLNs). Laparoscopic D2 lymphadenectomy is a complex operation and requires abundant technical expertise due to the complicated vessels, numerous anatomical layers and the complex lymph node metastasis pathway around the stomach. Therefore, many scholars still doubt whether LDG can achieve the same radical effect as open surgery. However, some publications have already described the number of RLNs in LDG with D2 dissection as similar to that in open gastrectomy [19, 20]. In addition, some researchers have reported not only a similar number of overall RLNs between laparoscopy and laparotomy, but also a similar number of specific lymph nodes, such as group 7, 8a, 9, 11p, 12a and 14v, which were considered difficult in laparoscopic dissection [21, 22]. In our study, the mean number of RLNs per patient was 30.4 ± 8.6, which was enough for curability and to determine lymph node metastasis. Park et al.  evaluated the long-term results of 239 patients who underwent LDG for the treatment of advanced gastric cancer (AGC). They found that the major recurrence was distant metastasis, whereas lymph node relapses were most frequent in para-aortic or distant lymph node metastasis. Therefore, they believe that the dissection of lymph nodes around the stomach can be performed efficiently by LDG. These studies and our data suggest that oncologically appropriate D2 lymphadenectomy can be carried out using laparoscopic surgery.
Cancer recurrence and long-term survival rate are two critical outcomes for evaluating surgical interventions in oncological therapy. In this study, the 5-year DFS rate and OS rate after LDG were 72.3% and 75.9%, respectively, which was similar to that in previous studies . In addition, the survival results stratified according to staging in the present study were comparable to historical data . With regard to recurrence pattern, peritoneal recurrences were more common in our study. However, some studies demonstrated that the hematogenous pattern was most common [26, 27]. Hao et al.  compared cancer cells following exfoliating peritoneal washing between laparoscopic and open gastrectomy for serosa-invaded AGC. The positive rates of free cancer cells were 39.68% and 44.26% in the laparoscopic and open groups, respectively, which was not significantly different. Therefore, we believe that the difference in recurrence pattern may due to the high proportion of T4a tumors in our cohort. Port-site metastasis caused by intraoperative pneumoperitoneum is another controversial issue. Shoup et al.  reported the long-term survival outcomes of 449 gastric cancer cases who received diagnostic laparoscopy, and only three cases developed port-site metastasis. They concluded that port-site implantation after laparoscopy was uncommon, and was not different from open incision site recurrence. This type of metastases was not reported in our study, similar to most other studies, thus we believe that pneumoperitoneum does not contribute to a higher risk of port-site metastasis.
Several previous studies [11, 12, 30, 31] reported some advantages of TLDG over LADG, such as reduced blood loss and faster recovery. However, in our study, we could not confirm the superiority of TLDG in postoperative recovery. Because LADG is performed using a minilaparotomy in the upper abdomen, it requires a longer incision than TLDG. Therefore, some researchers argued that LADG may be associated with greater analgesic use and more pain than TLDG. However, Kim et al.  and our data demonstrated that the small incision used for LADG does not appear to be associated with more pain, a greater inflammatory response, or delayed recovery. In addition, the proximal margin in LADG was shorter than that in TLDG in our study. These results may be related to the nature of LADG as it is difficult to pull the proximal stomach using a narrow incision, which may influence the distance of the proximal margin. It is noteworthy that our data do not reflect the effect of TLDG in patients with a high BMI. Some researchers  reported that the frequency of painkiller usage was higher in obese patients who underwent LADG. This means that TLDG may be more favorable than LADG in obese patients. In our practice, however, we found that TLDG does have some advantages during intraoperative manipulation. First, TLDG is an in situ operation that avoids excessive pulling on the internal organs. When conducting LADG, the gastric stump should be pulled out of the body. This pulling places tremendous stress on the gastric stump and may even lead to tearing of the spleen envelope, causing bleeding. Also, the short gastric blood vessels must be divided, especially in patients with tumors in a high location. Conversely, intracorporeal anastomosis could reduce stress on the gastric stump and retain its blood supply and function. Second, TLDG is more suitable for a “no touch tumor” operation. When conducting LADG, the operator is limited to working through a small incision, which leads to inevitable squeezing of the tumor. There is a higher possibility that the tumor will come into direct contact with the incision. When conducting TLDG, the surgeon can achieve a “zero extrusion”. Finally, in overweight patients, the auxiliary incision of LADG may need to be extended to 8–10 cm. However, when conducting TLDG, the surgeon can simply expand the incision for the 10-mm trocar below the umbilicus to a 3–4 cm semicircle incision around the navel to enable the sample to be removed as the hypogastrium wall has more ductility.