OBJECTIVETo investigate the association of tumor budding with recurrence and survival of patients with stage II colon cancer, in order to identify patients with high-risk recurrence who may benefit from adjuvant therapy.

METHODSClinical data of 112 stage II colon cancer patients in Guangzhou Red Cross Hospital between 1998 and 2007 were analyzed retrospectively. The degree of tumor budding was assessed by two observers and classified according to the number of tumor buds in the area with the greatest budding intensity on HE stain slides, as high-grade budding (≥10, n=30) and low-grade budding (≤9, n=82). Progression-free and cancer-specific survival were analyzed using the Kaplan-Meier method and Cox regression.

RESULTSAll the patients were followed up and the median follow-up was 78 months. The 5-year progression-free survival rates for patients with high-grade and low-grade budding were 65.3% and 90.7% respectively (P=0.008). The 5-year cancer-specific survival rates were 72.1% and 93.8% respectively (P=0.001). Cox regression analysis demonstrated tumor budding was an independent predictor of disease progression (RR=4.572, 95%CI:2.218-11.746, P=0.002) and cancer-related death (RR=4.116, 95%CI:1.657-10.384, P=0.012).

CONCLUSIONTumor budding is a strong prognostic index for adverse outcome in stage II colon cancer patients,which may serve as a prognostic marker to identify patients with high risk of recurrence who may benefit from adjuvant therapy.