In the early stage of rectal cancer, the self feeling is not obvious, while in the middle and late stage of rectal cancer, there is usually a more obvious feeling. At the early stage of rectal cancer, the cancerous focus is relatively small in size, which does not cause obvious intestinal stenosis, and its stimulation to the intestinal wall is also relatively mild. The focus does not have obvious collapse, and the intestinal function is basically normal, so there are generally no obvious clinical symptoms, and they generally do not feel it. In the middle and late stages of rectal cancer, the size of the focus increases, which may cause intestinal stenosis, affect the defecation function, and cause severe constipation or abnormal stool characteristics; The stimulation of cancerous focus on intestinal wall is enhanced, the focus is broken, and mucus and blood secretions may appear in stool; There may also be a sense of urgency and heaviness in the anus, which is generally obvious to patients.
