LAG shares obvious advantages of being minimally invasive and has the same short- and long-term efficacy compared with traditional open surgery in the treatment of early gastric cancer[6–9].Therefore, it has gradually become acknowledged by counterpart clinicians. Since 2002, the Japanese gastric cancer treatment guidelines have recommended laparoscopy-assisted gastrectomy as the standard procedure for early gastric carcinoma.
As experience with LAG for early gastric cancer has substantially increased, some surgeons have become concerned about laparoscopic surgery for AGC[10–14]. Ninety percent of patients diagnosed with gastric carcinoma in China have advanced-stage disease. The study of laparoscopic techniques in AGC would seem sensible Current evidence is compatible with D2 lymph node dissection as the preferred treatment for fit patients with AGC, in centers that can demonstrate low operative mortality[15, 16]. Furthermore, the Japanese gastric cancer treatment guidelines have adopted D2 lymph node dissection as the standard technique for AGC. However, the application of laparoscopic surgery for AGC remains questionable on account of the technical difficulty of D2 lymphadenectomy, and there has been few large-scale follow-up data on the oncologic adequacy of laparoscopic surgery compared with that of open surgery for AGC. Nevertheless, some small case-studies also showed that laparoscopic D2 lymphadenectomy is a safe procedure for AGC if the surgery is performed by experienced surgeons[13, 17, 18]. The Japanese gastric cancer treatment guidelines regard LAG as an investigational treatment. Some scholars[20–22] studying the laparoscopic learning curve have found that once surgeons span the learning curve reaching a plateau phase, the superiority of laparoscopic gastric carcinoma surgery will gradually appear more often compared with open surgery.
We have been performing LAG for gastric cancer since 2007. In the present study, we selected patients treated after January 2008, by which time we had overcome the learning curve having performed approximately 300 laparoscopic D2 gastrectomy procedures for gastric cancer, to reduce the influence of lack of surgical experience on the results. In this study, we compared 224 patients who underwent LAG with 112 who underwent OG for AGC without serosal exposure, in the same period. The data show that the LAG and OG groups shared similar operating times and first ambulation times, while the LAG group had less intraoperative blood loss, earlier recovery time for bowel movement, and a shorter postoperative stay in hospital. LAG was also shown to have obvious advantages of being minimally invasive for treatment of AGC without invasion of serosa.
The incidence of postoperative morbidity and mortality in the LAG group in the present study was similar to that of other reports. Although no significant difference in postoperative morbidity or mortality was observed between the LAG and OG groups (11.1% vs. 15.3%, and 0.9% vs. 1.8%, respectively, P > 0.05),our results show that LAG for AGC has similar intraoperative and postoperative complications to open surgery, and may even be better than OG. LAG D2 radical lymphadenectomy is a safe technique with fast postoperative recovery in the treatment of AGC without invasion of serosa. Therefore, LAG for AGC may be acceptable from this viewpoint.
The advantages of minimally invasive laparoscopic surgery have gradually been recognized, but laparoscopic D2 lymph node dissection is difficult to handle due to the complicated vessels, numerous anatomical layers and the complex lymph node metastasis pathway around the stomach. Therefore, many scholars still doubt whether LAG can achieve as considerable a radical effect as open surgery. Sato compared 36 cases of laparoscopy-assisted D2 lymph node dissection and 130 cases of open surgery for AGC. The average number of retrieved lymph node in the laparoscopic and open surgery group was (32 ± 12) and (35 ± 1) respectively, with no statistically significance difference. Martínez-Ramos presented a meta-analysis comparing laparoscopy to open surgery, predominantly in AGC. The study demonstrated no significant differences between the two groups in the number of dissected lymph nodes (weighted mean difference, WMD −1.57, 95% confidence interval −3.41 to 0.26, I-squared = 8.3). There studies suggested that LAG D2 radical surgery for AGC is feasible and safe and the number of harvested lymph nodes is the same as in open surgery. We found that skilled laparoscopic surgical technology and thorough palpation of anatomical layers under laparoscopy is the key to lymph node dissection. The laparoscopic amplification elaborately shows the finer structure of the vasculature, nerves and fascia, which helps surgeons to seek a specific fascia space and facilitates lymph nodes dissection in the vascular sheath. Furthermore, the ultrasonic scalpel is effective for cutting, for hemostasis and for minimizing damage to the surrounding tissues, which is suitable for vascular separation and lymph node dissection. The number of resected lymph nodes in our study was enough for curability and to determine lymph node metastasis. Our data show that the mean number of retrieved lymph nodes was not different between the LAG and OG group. Furthermore, the mean number of removed lymph nodes in each station was not significantly different with distal or total gastrectomy. For AGC without invasion of serosa, laparoscopy-assisted D2 lymphadenetomy is able to achieve the same effect on lymph node dissection as open surgery, regardless of the extent of the gastrectomy. The surgical approach (laparoscopy or open) did not appear to influence the lymph node yield.
To date, laparoscopic surgery for early gastric carcinoma has achieved favorable short- and long-term efficacy[6–8, 24, 25]. Although the efficacy of laparoscopic surgery for AGC is rarely reported, the results also show it can achieve almost the same short- and long-term efficacy as open surgery. Hur compared 26 cases of laparoscopic surgery and 25 cases of open surgery for treatment of AGC. The 3-year survival rate in the laparoscopy and open surgery groups was 88.2% and 77.2%respectively, with no statistical difference. A case–control study reported by Shuang demonstrated the same survival curve for laparoscopy versus open surgery during the same period and showed that laparoscopic surgery has similar long-term efficacy for treatment of AGC. Our study also showed that the survival curves for the LAG and OG groups were not significantly different (P > 0.05). LAG and OG have similar short survival times, but the long-term effect needs to be followed-up.
In summary, if surgeons are proficient in laparoscopic surgical techniques and comply with the principles of surgery, LAG D2 radical surgery can achieve similar, or even better effects compared to open surgery, and can achieve a comparative short-term clinical efficacy for treatment of AGC without serosal invasion. To establish laparoscopic surgery as a standard treatment for AGC, multicenter randomized controlled trials comparing the short- and long-term outcomes of laparoscopic versus open surgery are necessary.