Dissection of regional lymph nodes had been controversial until recently, but an accumulation of evidence has led us to conclude that D2 dissection should be the standard surgery for potentially curable advanced gastric cancer in most of the world, including Europe. Details of these studies are included in the Chap. 22. It is worth emphasizing the importance of the quality of surgical treatment in clinical trials. The initial three trials—the South African, the Hong Kong, and the Medical Research Council (MRC) trials1–3—had problems with the quality of the surgery. The first two trials were single institutional studies and, although hospital mortality was not high, survival data were poor. In the MRC study, there was no serious quality control for D2 surgery, and both hospital mortality and survival results for the D2 arm were poor. In the Dutch study, their quality effort made the results better than in the MRC study, but hospital mortality was nearly 10% after D2 dissection.4 Regarding overall long-term survival, D2 dissection was better than D1, although not systematically significantly. In 15-year follow-up, they demonstrated significantly better local control and disease-specific overall survival (OS).5 These results are not clear evidence but strongly suggest the benefit of D2 dissection in a Western population. Even in the Dutch study, most of participating surgeons had a quite limited experience with D2 surgery before the study and had quite low hospital volumes throughout the study. We would suggest that the quality of the surgery and postoperative care was not sufficient. All the meta-analyses comparing D1 and D2 resection are therefore unreliable. The Taiwanese study, a single institutional study comparing D1 versus D2, demonstrated significantly better OS after D2 dissection in Asian patients.6 Later, Hundahl et al, both in the INT-0116 and the Dutch studies, reported that insufficient nodal dissection reduces the OS of gastric cancer patients.7,8.
According to the recent Japanese gastric cancer treatment guidelines of the Japan Gastric Cancer Association (JGCA),9 a proximal margin of at least 3 cm is recommended for T2 or deeper tumors with an expansive growth pattern, and 5 cm is recommended for those with infiltrating growth pattern. When these rules cannot be applied, a frozen-section examination of the resection margin (in such cases as those invading the esophagus) is recommended. For T1 tumors, a gross resection margin of 2 cm should be obtained. However, tumor borders of T1 tumors are often unclear; stepwise biopsies are often appropriate preoperatively.
Laparoscope-Assisted Gastrectomy for Gastric Cancer
In Japan, many surgeons are performing laparoscope-assisted gastrectomy (LAG) for stage I tumors, although LAG is regarded as an experimental treatment even for stage I lesions in the guidelines. At the moment, there is no evidence demonstrating equivalence of long-term survival with this procedure. There are two large randomized controlled trials (RCTs) comparing ...