To Explore the Effect of Huaier Granule on the Negative Conversion Rate After the CEA Level Increases Again After Colorectal Cancer Surgery

Inclusion Criteria: * Age ≥18 years old, gender not limited * Diagnosed with colorectal cancer through histopathology, pTNM stage I-III * Previously underwent radical resection for colorectal cancer, with a postoperative evaluation of R0 * Imaging did not detect recurrence or distant metastasis * Serum CEA\>5.2ng/ml within 1 year after surgery (found during routine clinical follow-up) * Clear consciousness, language expression or reading ability, able to communicate normally, and cooperate to complete the questionnaire evaluation * Voluntary participation in this study, good compliance, and signing of informed consent form. Exclusion Criteria: * Known to be allergic to the components of Huaier Granule, or to avoid or use Huaier Granule with caution (observation group) * Cannot take medicine orally * Have received anti-tumor traditional Chinese patent medicines and simple preparations treatment within 1 month before enrollment (subject to the instructions) * Combining medical history of other malignant tumors * Diabetes with serious heart, cerebrovascular and lung diseases, severe hypertension and poor blood sugar control * Suffering from intestinal diverticulitis, rectal polyps, colitis, pancreatitis, cirrhosis, hepatitis, etc * Currently participating in clinical trials of other drugs * Pregnant or lactating women or those planning to conceive * Refusing to cooperate with follow-up visits * Other reasons led the investigators to believe that it was not suitable to participate in this study