Comparative analysis of station-specific lymph node yield in laparoscopic and open distal gastrectomy for early gastric cancer.

BACKGROUND: Randomized trials and cohort studies show that laparoscopic distal gastrectomy (LDG) achieves similar oncological results to open distal gastrectomy (ODG). However, studies have consistently demonstrated lower lymph node yield (LNY) for laparoscopic lymphadenectomy. Analysis of station-specific LNY may be useful in evaluating the reasons behind this difference.

OBJECTIVES: Comparison of station-specific LNY, surgical, and oncological outcomes between LDG and ODG for early gastric cancer.

METHODS: Patients who underwent R0 distal gastrectomy with histologically confirmed early gastric cancer were eligible for the study. All consecutive cases of LDG since the beginning of our experience with laparoscopic gastrectomy and synchronous cases of ODG with R0 resection were included in the study. Demographic, operative, histopathologic, and follow-up data were recorded in all patients.

RESULTS: A total of 259 cases of LDG and 95 cases of ODG were performed between 2000 and 2009. Patients undergoing LDG had longer operations but less bleeding (P<0.05). Postoperative complications were similar in both groups. The preoperatively planned extent of lymphadenectomy was D1 (stations 1, 3, 4sb, 4d, 5, 6, and 7), D1+ (D1with stations 8a and 9), or D2 (D1+ with stations 11p and 12a). During surgery, dissection of stations 3, 4d, 5, 6, and 7 was performed in all cases of LDG and ODG. Dissection of stations 1, 4sb, 8a, 9, 11p, and 12a was performed more frequently during ODG than during LDG. Consequently, the total LNY was 26.71 and 31.43 for LDG and ODG, respectively. Station-specific LNY was significantly lower for LDG than for ODG in the common hepatic artery nodes only (P<0.05). The mean follow-up was 43.6 months. Lymph node metastases, metastatic-to-resected lymph node ratio, recurrence, and cancer-related deaths were similar for LDG and ODG.

CONCLUSIONS: LDG was associated with less extensive lymph node dissection compared with ODG. Station-specific LNY was similar in all nodal stations except for the common hepatic artery nodes. In our experience, laparoscopic sub-D2 lymphadenectomy was adequate in the context of early gastric cancer and represents the future of gastric cancer resection in Japan.