Oncological impact of vascular invasion in colon cancer might differ depending on tumor sidedness

Abstract

Purpose Vascular invasion is a well-known independent prognostic factor in colon cancer and tumor sidedness is also being considered a prognostic factor. The aim of this study was to compare the oncological impact of vascular invasion depending on the tumor location in stages I to III colon cancer. Methods A retrospective analysis was performed using data from patients who underwent curative resection between 2004 and 2015. Patients were divided into right-sided colon cancer (RCC) and left-sided colon cancer (LCC) groups according to the tumor location. Disease-free survival (DFS) and overall survival (OS) were compared between the RCC and LCC groups, depending on the presence of vascular invasion. Results A total of 793 patients were included, of which 304 (38.3%) had RCC and 489 (61.7%) had LCC. DFS and OS did not differ significantly between the RCC and LCC groups. Vascular invasion was a poor prognostic factor for DFS in both RCC (hazard ratio [HR], 2.291; 95% confidence interval [CI], 1.186–4.425; p = 0.010) and LCC (HR, 1.848; 95% CI, 1.139–2.998; p = 0.011). Additionally, it was associated with significantly worse OS in the RCC (HR, 3.503; 95% CI, 1.681–7.300; p < 0.001), but not in the LCC group (HR, 1.676; 95% CI, 0.885–3.175; p = 0.109). Multivariate analysis revealed that vascular invasion was independently poor prognostic factor for OS in the RCC (HR, 3.186; 95% CI, 1.391–7.300; p = 0.006). Conclusion This study demonstrated that RCC with vascular invasion had worse OS than LCC with vascular invasion.

Is the oncological impact of vascular invasion more important in right colon cancer?

“…The authors suggest several possibilities for the prognostic impact of vascular invasion of right colon cancer. The vascular anatomy of the right colon is more complicated and variable than that of the left colon [ 4 ]. Moreover, manipulation of the tumor and its vasculature during surgery is more frequent for the right colon and it might result in the dissemination of tumor cells into the blood and lymphatic systems [ 6 ].…”

“…However, the differences in the dominant clinicopathological characteristics of right colon cancer such as female, advanced stage, poor oncologic outcomes, microsatellite instability, and mucinous adenocarcinoma raise many questions [ 5 ]. Although the vascular invasion shown in this study had a similar frequency for both right and left colon cancer, it is quite interesting that it was analyzed as a poorer prognostic factor in right colon cancer [ 4 ].…”

“…Shalkamy et al [ 4 ] evaluate the difference in the oncological impact of vascular invasion according to tumor side in colon cancer. The authors suggest that the oncological impact of vascular invasion could be worse in nonmetastatic right colon cancer than in nonmetastatic left colon cancer [ 4 ].…”