Laparoscopic ultrasound versus intraoperative gastroscopy for tumor localization in laparoscopic gastrectomy: a comparative cohort study

BACKGROUND: Precise tumor localization remains a technical challenge in laparoscopic gastrectomy. This study aimed to evaluate the efficacy and safety of laparoscopic ultrasound (LUS) as an alternative to conventional intraoperative gastroscopy (IOG) for tumor localization during laparoscopic radical gastrectomy. METHODS: We conducted a retrospective analysis of 58 patients who underwent laparoscopic radical gastrectomy between February 2023 and December 2024. Patients were categorized into LUS-guided (n = 22) and conventional IOG-guided (n = 36) localization groups. Intraoperative parameters (localization success, procedural times, blood loss), postoperative recovery metrics, complications, pathological outcomes, and short-term oncological results were compared between the two groups. Continuous variables were expressed as mean ± standard deviation or median with interquartile range and compared using Student’s t-test or Mann-Whitney U test. Categorical variables were presented as frequencies (%) and compared using χ² test or Fisher’s exact test. Statistical significance was set at p < 0.05. RESULTS: LUS demonstrated comparable localization success rates (95.5% vs. 100%, p = 0.379) with significantly shorter mean localization time (3.83 ± 0.26 vs. 4.06 ± 0.16 min, p = 0.001) and reduced total operative time (218.68 ± 28.48 vs. 240.69 ± 26.71 min, p = 0.004). Both groups showed equivalent safety profiles with no significant differences in complication rates (27.2% vs. 30.6%, p = 1.000). Pathological outcomes were excellent in both groups, with 100% R0 resection rates and comparable lymph node yields (32.5 vs. 38.0, p = 0.320). Short-term recurrence rates were equivalent (4.5% vs. 5.6%, p = 1.000) after a mean follow-up of 12 months. CONCLUSION: LUS-guided tumor localization represents an efficient and effective alternative to IOG, significantly reducing operative time while maintaining equivalent safety and oncological outcomes. This surgeon-controlled technique integrates seamlessly into the laparoscopic workflow and offers a practical solution for intraoperative tumor localization in minimally invasive gastric surgery.