Adjuvant chemotherapy in stage II and III colon cancer: the role of the “budding and TILs-(tumor-infiltrating lymphocytes) combination” as tumor-host antagonists

PURPOSE: To analyze the influence of adjuvant chemotherapy on the combination of tumor budding and tumor-infiltrating lymphocytes (TILs) in stage II and III colon cancer and to elucidate its potential value for adjuvant treatment decisions. METHODS: 306 patients with stage II and 205 patients with stage III colon cancer diagnosed between 2005 and 2016 who had undergone surgery in a curative setting were enrolled. Budding and TILs were assessed according to the criteria of the International Tumor Budding Consensus Conference (ITBCC) and the criteria of the International TILs Working Group (ITWG). Combinations of budding and TILs were analyzed, and the influence of adjuvant chemotherapy was assessed. RESULTS: In stage II colon cancer, stratification into the four budding/TILs groups showed no significant differences in overall survival (OS) between the chemotherapy and the surgery-alone group, not even in cases with high-risk features. In stage III colon cancer, patients with low budding/high TILs benefited significantly from chemotherapy (p=0.005). Patients with high budding/low TILs as well as high budding/high TILs showed a trend to benefit from adjuvant treatment. However, no chemotherapy benefit was seen for the low budding/low TIL group. CONCLUSIONS: The budding/TIL combination identified subgroups in stage II and III colon cancer with and without benefit from adjuvant treatment. The results this study suggest that the combination of budding and TILs as tumor-host antagonists might be an additional helpful tool in adjuvant treatment decisions in stage II and III colon cancer.