A positive fh test for rectal epithelial cell stability means that the rectal epithelial cells are not stable, suggesting the possibility of rectal cancer. The fh substance in rectal epithelial cells mainly exists in the form of binding in cell proteins. When the cell stability is poor, the proteins under the action of disease-causing factors undergo structural changes, so that the fh substance can be dislodged from the proteins in the cells, and be detected by the fh test, resulting in a positive result. Rectal epithelial cell stability fh test belongs to the rectal malignant tumor early screening means, often has a certain misdiagnosis rate, need to be combined with the colonoscopy, the results of the examination can have a high rate of accuracy. The gold standard for diagnosing tumors is pathological examination, so patients need to send samples for pathological examination immediately after colonoscopy, and the results of pathological examination will prevail. Patients should not have greater psychological pressure, actively cooperate with doctors to conduct relevant examinations, and carry out relevant treatments under doctors’ guidance. If there is no abnormality in the pathology examination, patients can have regular review afterward.