[Prognostic risk factors associated with recurrence after curative resection in patients with stage II colorectal cancer].

The aim of this study was to clarify the risk factors associated with recurrence in patients with stage II colorectal cancer.We performed a retrospective analysis of 316 patients with stage II colorectal cancer who underwent gross radical colectomy between 1994 and 2003.The overall recurrence rate was 10.8%. Univariate analysis identified 5 risk factors associated with recurrence: depth of tumor invasion (tumor penetration of the serosa[SE]-tumor invasion of adjacent structure[s SI]), lymphatic invasion( ly2-3), venous invasion( v2-3), budding( grade 2-3), and perineural invasion (PN1). Multivariate analysis identified 3 risk factors associated with recurrence: budding (grade 2-3; p=0.008), depth of tumor invasion( SE-SI; p=0.008), and venous invasion( v2-3; p=0.034).The results of this study suggest that active postoperative adjuvant chemotherapy should be considered for the treatment of patients with stage II colorectal cancer with budding( grade 2-3), venous invasion( v2-3), or tumor depth of SE or SI.