Prognostic Impact of Tumor-Budding Grade in Stages 1-3 Colon Cancer: A Retrospective Cohort Study.

Abstract

Tumor budding is associated with adverse histology and is a predictor of lymph node metastasis. However, it remains unclear whether tumor budding is predictive of a poor prognosis for colon cancer patients. This study sought to investigate the prognostic significance of tumor budding in colon cancer. This study evaluated 4196 colon cancer patients who underwent radical surgery from 2007 to 2013 at a single institution. The patients were categorized according to tumor-budding status. Adjustment was made for using propensity score-matched analysis, and both disease-free survival (DFS) and overall survival (OS) were compared between the groups. Among the 4196 patients, 2269 had low budding (<5 buds), 1312 had intermediate budding (5-9 buds), and 615 had high budding (≥10 buds). High budding was associated with adverse histologic features such as elevated levels of preoperative carcinoembryonic antigen, advanced stage, poor histology, and the presence of lymphatic/vascular/perineural invasion. Before matching, DFS and OS decreased significantly with increasing tumor budding. After matching, the difference in survival between the low- and intermediate-budding groups disappeared. However, the OS and DFS rates for the high-budding group were significantly lower than for the other two groups. In the multivariate analysis of prognostic factors, high budding was an independent poor prognostic factor in DFS and OS, whereas tumor-budding positivity itself was not an independent prognostic factor. Tumor-budding grade rather than tumor-budding positivity was an independent prognostic factor in colon cancer.