The fundamental difference between colon cancer and rectal cancer lies in their locations of occurrence. Both are collectively referred to as colorectal cancer, which is one of the more prevalent malignancies of the digestive system in China. Colon cancer originates from the mucosa of the colon, while rectal cancer originates from the mucosa of the rectum, with different points of origin. In terms of treatment, there are significant differences between colon and rectal cancer. In surgical treatment, both cancers typically require surgery as the first choice. However, patients with colon cancer can preserve their anus, whereas some patients with low rectal cancer might face situations where anus preservation is not possible. In internal medicine, the chemotherapy drugs used for colon and rectal cancer are quite similar. In terms of radiation therapy, there are notable differences; radiation treatment is generally not included for colon cancer but is an important treatment method for rectal cancer.