Comparison of D2 and Non-D2 Lymphadenectomy in Older Patients (≥75 years) Undergoing Minimally Invasive Distal Gastrectomy for Gastric Cancer: A Multicenter Retrospective Propensity Score-matched Analysis

Background/Aim: This multicenter retrospective cohort study with propensity score matching (PSM) evaluated the surgical outcomes and prognosis of minimally invasive distal gastrectomy (MIDG) with D2 lymphadenectomy (LND) in older patients (≥75 years) with gastric cancer (GC). Patients and Methods: We retrospectively enrolled 988 patients who underwent MIDG for GC at five institutions between January 2018 and December 2024. Older patients with GC (cN+ or ≥cT2) were categorized into two groups: those who received D2 LND (D2 group) and those who did not (Non-D2 group). PSM was performed using the following covariates: age, sex, body mass index, American Society of Anesthesiologists physical status classification, surgical approach (laparoscopic or robotic), reconstruction method (Billroth I, Billroth II, or Roux-en-Y), adjuvant chemotherapy, and clinical T/N stage according to the Japanese Classification of Gastric Carcinoma. Surgical outcomes and prognoses were compared between groups. Results: A total of 186 eligible patients were identified (D2: 74; Non-D2: 112), and 82 patients (41 per group) were included after matching. Operation time was significantly shorter in the Non-D2 group [D2: 349 min (176-507) vs. Non-D2: 285 min (138-458); p=0.025). The incidence of postoperative complications (Clavien–Dindo grade ≥II) was comparable between groups. The median follow-up was 23.3 months (range=1-79.4) in the D2 group and 26.2 months (range=1-79.5 months) in the Non-D2 group. No significant differences were observed in 5-year overall survival (D2: 47.7% vs. Non-D2: 34.6%; p=0.143) or 5-year relapse-free survival (RFS) (D2: 34.3% vs. Non-D2: 27.2%; p=0.578). Multivariable analysis identified pathological lymph node metastasis as an independent prognostic factor for RFS (hazard ratio= 3.553; 95% confidence interval=1.263-9.996; p=0.016). Conclusion: Among older patients (≥75 years) undergoing MIDG for GC, D2 LND was associated with longer operation time without significant differences in survival outcomes.