Time-Dependent Recovery of Gastric Emptying After Gastrectomy: A 12-Month Longitudinal Study Using a C-Acetate Breath Test With a Semi-Solid Meal.

[AIMS] Gastric emptying dysfunction is a major concern after gastrectomy for gastric cancer; however, its long-term course and relationship with surgical procedures remain unclear. This study aimed to evaluate gastric emptying function longitudinally over 12 months postoperatively using the C-acetate breath test with a semi-solid meal.

[METHODS] A prospective cohort of 95 patients who underwent curative gastrectomy for gastric cancer between April 2021 and July 2024 was assessed. A novel semi-solid test meal, integrated with a C-acetate breath test, was used to evaluate patients' gastric emptying function. Gastric emptying half-time (T1/2) was measured preoperatively and at 1, 6, and 12 months postoperatively. Patients were stratified according to surgical procedure and reconstruction method.

[RESULTS] The median T1/2 was 42.0 min preoperatively, delayed to 45.9 min at 1 month, and then significantly decreased to 23.4 min at 6 months and 18.7 min at 12 months postoperatively. In distal gastrectomy with Billroth I or Roux-en-Y reconstruction, T1/2 was prolonged at 1 month but improved markedly at 6 and 12 months. In contrast, proximal gastrectomy with modified side-overlap esophagogastrostomy and total gastrectomy showed consistently rapid gastric emptying at all time points.

[CONCLUSION] Gastric emptying function after gastrectomy demonstrated dynamic, time-dependent changes, with an initial postoperative delay followed by significant acceleration within the first year. The pattern and degree of change differ depending on the surgical procedure and reconstruction method. These findings highlight the importance of individualized, and time-adapted nutritional management after surgery in patients with gastric cancer.