[A preliminary exploration of reduced port laparoscopic proximal gastrectomy with right-sided overlap and single-flap valvuloplasty (ROSF)].

<b>Objective:</b> This study aimed to share preliminary experiences of single-incision plus two ports laparoscopic proximal gastrectomy with right-sided overlap and single-flap valvuloplasty (ROSF). <b>Methods:</b> Following the 6th edition of the Japanese Gastric Cancer Treatment Guidelines, proximal gastrectomy with lymphadenectomy was performed. Using a single-port approach, the esophagus was transected at least 2 cm above the tumor's upper margin with linear staplers. The stomach was then extracted through a periumbilical incision, and the proximal stomach was subsequently transected extracorporeally, while ensuring appropriate resection margins on both the greater and lesser curvatures. A single flap was created before returning the remnant stomach to the abdominal cavity and re-establishing pneumoperitoneum. The No.2 clip was used to grasp and elevate the esophageal stump. An incision was made at the right lower edge of the esophageal stump to guarantee that the esophageal lumen was open. The linear stapler was then inserted into the openings of the stomach and esophagus to perform a side overlap anastomosis with a length of 3 cm. Another barbed suture was used to close the common opening of the esophagus and the stomach, and the same barbed suture were used to suture the gastric wall to the lower edge of the muscle flap. The first barbed suture was then used to sequentially suture the proximal brim of the flap to the esophagus and the right brim of the flap to the right brim of the mucosal window. After completion of anastomosis, a drainage tube was inserted through the right upper port. This procedure was employed from November 2023 to March 2024 on five patients diagnosed with adenocarcinoma of the esophagogastric junction and upper stomach. The cohort consisted of three males and two females, with an age range of 62 to 75 years and a body mass index (BMI) of 13.7 to 24.2 kg/m². All cases were preoperatively staged as T1-2N0M0, confirmed by endoscopic biopsy and enhanced CT scans of the chest, abdomen, and pelvis. <b>Results:</b> All five patients successfully underwent the surgery. The median surgery time was 180-325 minutes, with the intraoperative blood loss of 30-50 ml. The number of lymph nodes harvested ranged from 18 to 27. The time to first flatus, and restore liquid diet and was 2.0-5.0 and 1.0-3.0 days, respectively. The postoperative length of stay was 9.0-11.0 days. The pain scores on the Numeric Rating Scale (NRS). On the first day, the pain scores were 3.0 in two cases, 2.0 in two cases, and 1.0 in one case. On the second day, the pain scores were 2.0 in two cases and 1.0 in three cases. On the third day, the pain scores were 1.0 in four cases and 2.0 in one case. No short-term postoperative complications were observed, and there were no perioperative deaths. <b>Conclusion:</b> Single-incision plus two ports laparoscopic proximal gastrectomy with ROSF is safe and feasible.