[Anatomical ideas on infrapyloric lymphadenectomy in sagittal view of laparoscopic radical gastrectomy for gastric cancer].

Objective: To preliminarily discuss the anatomical ideas on infrapyloric lymphadenectomy in the sagittal view of laparoscopic radical gastrectomy for gastric cancer.

Methods: A retrospective review was performed on the clinical data of 98 patients of lower-middle stomach cancer who underwent D2 radical gastrectomy in Department of Gastrointestinal Surgery of The First Hospital of Jilin University from June 2015 to December 2016. There were 56 males and 42 females with an average age of 59 years. TNM staging of gastric cancer revealed 22 cases of stage I, 37 cases of stage II, and 39 cases of stage III. All the patients underwent standardized No.6 lymph node dissection. Patients in stage II and above also received dissection of No.14v lymph nodes. During operation, sub-regional lymph node dissection was performed in the infrapyloric region according to sagittal anatomy. The dissection of each sub-region was to expose the corresponding anatomical landmarks as quality control standards. The region under the stomach pylorus was divided into the upper and lower parts by the pancreatic anterior plane and the gastroduodenal artery. The lower part was 6v region, and the upper part was 6a and 6i region. The lower part was further divided into front region and rear region by right vein of gastric omentum. The upper part was further divided into front, middle and posterior parts by right vein of gastric omentum and inferior pyloric artery. A total of 5 regions were established. Lymph node dissection in the lower pyloric region was performed at these five regions. Photographs were taken during operation and statistics was carried out in operation time and harvested lymph nodes from infrapyloric lymphadenectomy.

Results: The time to complete No.6 lymph node dissection was (38±6) minutes for the 22 patients with stage I gastric cancer, and to finish No.6 and No.14v lymph node dissection was (49±8) minutes for the 76 patients with stage II and stage III gastric cancer. The mean number of harvested No.6 lymph nodes was 5.4±2.9, including 2.9±1.8 in No.6a,1.3±0.9 in No.6v, and 1.2±0.7 in No.6i. No.6 lymph node metastasis was found in 29 cases (29.6%), and No.14v lymph node metastasis in 19 patients (9.2%).

Conclusion: Sub-regional lymphadenectomy for infrapyloric region based on embryology and membrane anatomy may achieve complete dissection of No.6 lymph nodes.