To explore the effect of unfavorable histological features on the clinical outcomes of patients receiving radical resection of colon cancer.

Inclusion Criteria:

1. Age: 18-100 years old;
2. Postoperative pathology confirmed colon adenocarcinoma;
3. The tumor is located from the cecum to the sigmoid colon;
4. No distant organ metastasis;

Exclusion Criteria:

1. Simultaneous or metachronous multiple primary colorectal cancer;
2. History of previous malignant tumors (except for completely cured cervical carcinoma in situ or basal cell carcinoma or squamous epithelial skin cancer)
3. local excision procedure;
4. palliative resection (R2 resection);
5. pregnant or lactating women.

Colon cancer patients with or without unfavorable histological features

Individual participant data can be shared with all researchers involved in the study.