6. Limitations
tumor
TUMOR, INFILTRATION
Our study has some limitations. First, the population in our cohort comprised of persons from one region of China (Wuhan), which may limit the generalizability of the predictive models and require further validation in patients from different geographic regions. Second, this was a nonrandomized retrospective analysis. Therefore, potentially biased comparisons such as in the inclusion of patients or sample selection bias could have occurred. Third, the included indicators need to be refined; for example, the location of the tumor needs to be subdivided into left or right and proximal or distal colon. Crohn's-like reaction and tumor lymphocyte infiltration also need to be included in the model. Finally, we only performed internal validation in this study, and further external validation groups are needed to verify the predictive effect.