D2 lymph node dissection confers little benefit on the overall survival of older patients with resectable gastric cancer: a propensity score-matching analysis of a multi-institutional dataset.

Aging societies comprise an increasing number of elderly gastric cancer (GC) patients. We herein attempted to determine whether D2 lymphadenectomy is beneficial for older GC patients. We retrospectively analyzed a multi-institutional dataset including 3484 patients who received surgical resection for GC. For the analysis, we selected patients aged ≥ 80 years who were clinically diagnosed with T1N + or T2-4 GC. To balance the essential variables including the type of gastrectomy and the stage of progression, propensity score matching was conducted, and we compared the background clinical factors and postoperative outcomes of the patients allocated to the D2 (n = 87) and non-D2 (n = 87) dissection groups. The D2 group had significantly longer operative times, more blood loss, and more retrieved lymph nodes (median 32 vs 24, P < 0.001) than the non-D2 group. The D2 group had a greater incidence of intra-abdominal abscesses (grade ≥ II in the Clavien-Dindo classification) than the non-D2 group (3.5% vs 0%, P = 0.040). The overall disease-specific and relapse-free survival rates of the D2 group tended to be poorer than those of the non-D2 group (hazard ratios 1.49, 1.70 and 1.14, respectively). D2 lymphadenectomy for older patients with GC conferred little benefit regarding overall survival despite an occurrence of increased complication rates.