OBJECTIVES: This study was designed to clarify which attributes of stage II colon cancer are associated with tumor recurrence and survival after curative resection, and the effects of adjuvant chemotherapy (ACT). METHODS: We retrospectively reviewed outcomes and clinicopathological characteristics of 1476 patients with stage II colon cancer who underwent curative resection. RESULTS: Of 1476 patients, 204 (13.8%) developed recurrence. Macroscopic type, serum CA19-9 levels, venous invasion, emergency operation, and postoperative ileus were independently associated with overall recurrence. Carbohydrate antigen (CA)19-9 levels, the number of dissected lymph nodes (LN), sex, age, ACT, emergency operation, venous invasion, and macroscopic type were independently associated with poor prognosis. Prognosis was significantly better in patients who received ACT than in those who did not. Among patients with extensive venous invasion, those with fewer than 13 dissected LNs, male patients, and patients >50 years old, the prognosis was significantly better in patients who received ACT than in those who did not. CONCLUSIONS: ACT for stage II colon cancer is recommended to improve the prognosis of patients with extensive venous invasion, patients with fewer than 13 dissected LNs, patients >50 years old, and male patients, particularly patients with more than two of these risk factors.
OBJECTIVES: This study was designed to clarify which attributes of stage II colon cancer are associated with tumor recurrence and survival after curative resection, and the effects of adjuvant chemotherapy (ACT). METHODS: We retrospectively reviewed outcomes and clinicopathological characteristics of 1476 patients with stage II colon cancer who underwent curative resection. RESULTS: Of 1476 patients, 204 (13.8%) developed recurrence. Macroscopic type, serum CA19-9 levels, venous invasion, emergency operation, and postoperative ileus were independently associated with overall recurrence. Carbohydrate antigen (CA)19-9 levels, the number of dissected lymph nodes (LN), sex, age, ACT, emergency operation, venous invasion, and macroscopic type were independently associated with poor prognosis. Prognosis was significantly better in patients who received ACT than in those who did not. Among patients with extensive venous invasion, those with fewer than 13 dissected LNs, male patients, and patients >50 years old, the prognosis was significantly better in patients who received ACT than in those who did not. CONCLUSIONS: ACT for stage II colon cancer is recommended to improve the prognosis of patients with extensive venous invasion, patients with fewer than 13 dissected LNs, patients >50 years old, and male patients, particularly patients with more than two of these risk factors.