Which patients with isolated para-aortic lymph node metastasis will truly benefit from extended lymph node dissection for colon cancer?

Abstract

Purpose The prognosis of patients with colon cancer and para-aortic lymph node metastasis (PALNM) is poor. We analyzed the prognostic factors of extramesenteric lymphadenectomy for colon cancer patients with isolated PALNM. Materials and Methods We retrospectively reviewed 49 patients with PALNM who underwent curative resection between October 1988 and December 2009. Results In univariate analyses, the 5-year overall survival (OS) and disease-free survival (DFS) rates were higher in patients with ? 7 positive para-aortic lymph node (PALN) (36.5% and 27.5%) than in those with > 7 PALN (14.3% and 14.3%; p=0.010 and p=0.027, respectively), and preoperative carcinoembryonic antigen (CEA) level > 5 was also correlated with a lower 5-year OS and DFS rate of 21.5% and 11.7% compared with those with CEA ? 5 (46.3% and 41.4%; p=0.122 and 0.039, respectively). Multivariate analysis found that the number of positive PALN (hazard ratio [HR], 3.291; 95% confidence interval [CI], 1.309 to 8.275; p=0.011) was an independent prognostic factor for OS and the number of positive PALN (HR, 2.484; 95% CI, 0.993 to 6.211; p=0.052) and preoperative CEA level (HR, 1.953; 95% CI, 0.940 to 4.057; p=0.073) were marginally independent prognostic factors for DFS. According to our prognostic model, the 5-year OS and DFS rate increased to 59.3% and 53.3%, respectively, in patients with ≤ 7 positive PALN and CEA level ≤ 5. Conclusion PALN dissection might be beneficial in carefully selected patients with a low CEA level and less extensive PALNM.