Purpose: This study examined the possibility of performing a limited resection and a lymphadenectomy with sentinel node navigation surgery (SNNS) for the treatment of proximal gastric carcinoma.
Methods: Thirty patients with cT1N0 (n = 23) and cT2N0 (n = 7) proximal gastric carcinoma that was located primarily in the U area (the upper third of the stomach) were enrolled. indocyanine green (ICG; 0.5 ml) was injected endoscopically into the submucosa of the four quadrants encompassing the cancer. Twenty minutes after injection, infrared ray electronic endoscopy (IREE) was used to identify the lymph nodes that were stained with ICG (sentinel nodes, SNs) around the serosa and surrounding fat tissue.
Results: One hundred percent of the SNs were identified with our SNNS method. The most common location of SNs was No. 3 (T1: 78%, T2: 100%). The main route of lymphatic drainage was from No. 1 or No. 3 to No. 7 (T1: 95%, T2: 100%). In T1 cancer, Indocyanine green was not distributed to the right gastric area, and no patients had SNs in No. 5 or No. 8a. Four cT2 cancer patients had lymph node metastases, all of which were SNs. There were no cases of postoperative metastasis or recurrence.
Conclusions: For the cT1 proximal gastric carcinoma patients, limited dissection of the ICG tracer-positive lymphatic areas alone by SNNS using IREE may be acceptable. The main lymphatic drainage route of proximal gastric carcinoma is the left gastric artery area (Nos. 1, 3, and No. 7) and dissection of this area is important.