Survival benefit of lymph node dissection in surgery for colon cancer in elderly patients: A multicenter propensity score-matched study in Japan.

INTRODUCTION: In surgery for elderly patients with colorectal cancer, it is unclear whether radical lymph node (LN) dissection safely offers a survival benefit. The aim of the study was to evaluate the impact of the LN yield in elderly patients undergoing surgery for colorectal cancer.

METHODS: The subjects were selected from a surgical database of 2065 patients aged ≥80 years old who underwent surgery for colorectal cancer at 41 hospitals in Japan between 2003 and 2007. The patients were divided into groups according to the number LN harvested: <12 and ≥12. Propensity scores were subsequently matched to balance the baseline characteristics.

RESULTS: Of the 954 patients initially selected, 331 were in the <12 LN and 623 were in the ≥12 LN group. After cases were matched, 293 patients were allocated to each group, and all covariates were balanced. For short-term outcomes, the time for surgery was longer in the ≥12 LN group, but there was no significant difference in morbidity between the groups. Overall, relapse-free and cancer-specific survival rates were higher in the ≥12 LN group (P = 0.004, 0.001, and 0.02).

CONCLUSIONS: In patients aged ≥80 years old with stage II-III colon cancer, harvesting ≥12 LN provides a survival benefit, and therefore, limited LN dissection is not recommended in these patients.