Distal laparoscopic gastric resection and gastrectomy in gastric cancer
In Germany, minimally invasive gastric surgery began in 1994 with the first laparoscopic BI resection and in 1996 with the first gastrectomy (1, 2). In benign gastric tumors and GIST, MIS techniques are now established standards whose widespread application is limited only by tumor size and location.
In gastric cancer, however, the situation is different. This is because of the less complex measures needed to manage benign gastric wall processes, obviating the need for systematic lymphadenectomy or, at times, complex reconstruction of the gastric passage.
Current study findings
At present, there have been 9 randomized trials comparing laparoscopic and open distal gastric resection in gastric cancer (5-13) - none on gastrectomy - and 13 meta-analyses (14-26). The studies include early cancers as well as locally advanced tumors, different resection variants (distal and subtotal resection, gastrectomy), different types of lymphadenectomies (D1 and D2), and different resection techniques (BI and BII, Roux-en-Y, stapled suture, manual suture). Most of the studies are from Asia, with only one study from western countries (8).
For distal laparoscopic gastric resection as well as laparoscopic gastrectomy in gastric cancer, the meta-analyses revealed significantly less intraoperative blood loss compared to open surgery. All meta-analyses reported significantly longer operating times for MIS procedures than for open procedures (16, 17). According to a meta-analysis from the United States, the conversion rate ranges from 0% to 6.2% (22).
Systematic D2 lymphadenectomy (D2-LAD) of compartments I and II represents the current standard of care in gastric cancer surgery (4, 27). The oncological benefit of D2-LAD compared with the less radical D1-LAD is supported by the 2010 Dutch Gastric Cancer Study (28). According to the results of anatomic studies and the German Gastric Carcinoma Study, the computed number of lymph nodes to be resected in open procedures should be 25 (29, 30, 31). This benchmark also applies to laparoscopic lymphadenectomies. In 9 of 13 meta-analyses, open LAD resulted in a higher number of excised lymph nodes than in laparoscopic LAD, and 4 analyses yielded comparable results.
As measured by postoperative analgesic consumption, laparoscopic gastric resections, like other MIS procedures, are significantly less painful postoperatively compared with open procedures (32). In 8 meta-analyses, hospital length of stay in laparoscopic surgery was shorter than in open resection, and 3 analyses found no difference. One analysis published in 2014 reported a reduction of about 4 days in postoperative length of stay after laparoscopic surgery (23).
In terms of postoperative mortality, almost all analyses demonstrated benefits for MIS resections regarding wound infections (22, 32). However, not all studies found less postoperative pulmonary complications in MIS (32). Serious surgical complications such as pancreatic fistulas and suture line failures occur was similar in both surgical techniques. Nor did the meta-analyses identify any difference in the mortality rates between laparoscopic and open gastric resections.
The long-term oncological outcomes for distal resections in early cancer and gastrectomy are the same for laparoscopic and open techniques. However, the outcomes are of limited validity because the vast majority of studies did not document long-term outcomes. The same is true for the quality of life. In a prospective randomized study from Korea on 164 patients with T1 carcinomas, patients undergoing MIS showed significant benefits within the first 3 months in terms of loss of appetite, fatigue, dysphagia, and sleep disorders (33). However, improved long-term quality of life compared with open procedures was not demonstrated (34). A Japanese study from 2014 came to the same conclusion (35).
Conclusion: Due to the poor current data, final evaluation of minimally invasive surgery is not yet possible. Larger case series and data from the Asian region demonstrate in principle the good technical feasibility and, in oncological indications, outcomes comparable to those in open surgery.