PURPOSE: An individualized surveillance protocol based on stratified prognostic factors is needed for the early detection of recurrent disease. The aim of this study was to determine both the clinicopathological characteristics for early-recurring colorectal cancer and the impact on survival. METHODS: From January 1996 to September 2000, 1,504 patients with curatively resected colorectal cancer were recruited. The primary goal of this study was to evaluate the time interval until first loco-regional or distant recurrence, and the secondary goal was the last survival status. Early recurrence was defined as recurrence within the first 12 months postoperatively. Clinicopathologic data and preoperative CT records were reviewed. The follow-up period was over 48 months. RESULTS: The 5-year recurrence rate was 25.4%, and 39.5% of these were detected within the first 12 months postoperatively. In the multivariate analysis, the independent prognostic factors for early recurrence were cell differentiation (PD/MUC/SRC), lymphovascular invasion, and absence of adjuvant chemotherapy in stage III and curatively resected colorectal cancer in stage IV. Inaccurate interpretation by a low-quality CT scan resulted in a stage III cancer being understaged preoperatively. The 5-year overall survival rate according to the recurrent time interval was significantly different (early recurrence: 7.4% vs. late recurrence: 23.6%, P<0.05). The resection rate was similar in both groups (early recurrence: 22.7% vs. late recurrence: 27.6%, P=0.392). CONCLUSIONS: Colorectal cancer that recurred within 12 months showed more aggressive biologic behaviors and poor survival. Understaging caused by incomplete preoperative evaluation for disease extension may cause treatment failure.