Prognostic Significance of Enlarged Lymph Nodes in Stage II Colorectal Cancer

BACKGROUND: Many studies have reported a correlation between lymph node metastasis and prognosis in patients with colorectal cancer. However, the clinical significance of enlarged lymph nodes for prognosis has scarcely been explored. OBJECTIVE: This study aimed to assess the clinical significance of enlarged lymph nodes in stage II colorectal cancer. DESIGN: This is a multicenter retrospective observational study with a median follow-up period of 66.8 months. SETTINGS: Patients' medical records were retrospectively collected from the Japanese Study Group for Postoperative Follow-up of Colorectal Cancer database. PATIENTS: This study included 2212 patients with stage II colorectal cancer who underwent surgical resection between January 2009 and December 2012. Patients were classified into the enlarged lymph node and nonenlarged lymph node groups and their data were compared. MAIN OUTCOME MEASURES: Clinicopathological characteristics and prognoses of the 2 groups were compared. The main outcomes measured were recurrence-free survival and overall survival. RESULTS: The enlarged lymph node group showed significantly better overall survival and recurrence-free survival in pT4b cases but not in pT3 or pT4a cases. In pT4b cases, an enlarged lymph node (HR, 0.53; 95% CI, 0.29-0.98) was an independent prognostic factor for longer recurrence-free survival, whereas a rectal lesion (HR, 3.46; 95% CI, 1.90-6.29) was an independent prognostic factor for shorter recurrence-free survival. An enlarged lymph node was associated with a lower distant recurrence rate (HR, 0.49; 95% CI, 0.26-0.92) and a tendency to correlate with better overall survival (HR, 0.50; 95% CI, 0.22-1.14). LIMITATIONS: The retrospective design may have increased the risk of selection bias. Inadequate information regarding enlarged lymph nodes is another study limitation. CONCLUSIONS: This study showed that enlarged lymph nodes are associated with a favorable prognosis in patients with pT4b stage II colorectal cancer. See Video Abstract at http://links.lww.com/DCR/C246.