This study is a prospective, single center, observational study, expected to include patients who visited the selected research center from December 2022 to December 2024 and were pathologically diagnosed with stage I-III colorectal cancer and underwent R0 radical resection surgery. During routine clinical follow-up within one year after radical surgery, if serum CEA\>5.2ng/ml occurs, patients may choose whether to use Huaier granules to prevent recurrence and metastasis according to their wishes. Patients who agree to use Huaier granules will enter the observation group; Patients who do not agree to use it will enter the control group. After the subjects are enrolled, they will be visited every 1 month ± 7 days in the first year, and every 3 months ± 14 days starting from the second year according to clinical routine diagnosis and treatment, until imaging examination determines disease progression, the end of the study, intolerable toxicity, withdrawal from the study for any reason or death, or the researcher determines no longer benefiting, whichever occurs first.
