Is there no need to discuss adjuvant chemotherapy in stage II colon cancer patients with high tumor budding and lymphovascular invasion?

ABSTRACT

PURPOSE: The aim of this study is to evaluate the clinicopathologic associations of tumor budding (Bd) as well as other potential prognosticators including lymphovascular invasion (LVI) in T3/4aN0 colon cancer patients and to investigate their impact on the outcome. METHODS: The patients were enrolled in three groups according to the number of budding as Bd1 (0-4 buds), Bd2 (5-9 buds), and Bd3 (> 10 buds). These groups were retrospectively compared in terms of demographic features, other tumor characteristics, operative outcomes, recurrences, and survival. The mean follow-up time was 58 ± 22 months. RESULTS: A total of 194 patients were divided as follows 97 in Bd1, 41 in Bd2, and 56 in Bd3 groups. The Bd3 group was associated with significantly higher LVI and larger tumor size. The rate of recurrence increased progressively from 5.2% in Bd1 to 9.8% in Bd2 and to 17.9% in Bd3 group (p = 0.03). More importantly, the 5-year overall survival (OS Bd1 = 92.3% vs. Bd2 = 88% vs. Bd3 = 69.5%, p = 0.03) and disease-free survival (DFS Bd1 = 87.9% vs. Bd2 = 75.3% vs. Bd3 = 66%, p = 0.02) were significantly worse in Bd3 group. In addition, in the subgroup of patients with the presence of Bd3 and LVI together, the 5-year OS (60% vs. 92%, p = 0.001) and DFS (56.1% vs. 85.4%, p = 0.001) were significantly worse. In multivariate analysis, Bd3+LVI was significantly associated with poor OS and DFS (p < 0.001). CONCLUSION: In patients with T3/4aN0 colon cancer, high tumor budding negatively affects long-term oncological outcomes. These findings strongly suggest that adjuvant chemotherapy be considered for the patients with Bd3 and LVI together.