What color the blood in rectal cancer stool is depends mainly on the amount and speed of bleeding. If the bleeding amount is relatively small and the bleeding speed is slow, the exuded blood usually adheres to the surface of stool, making the stool look dark red, and if it is mixed with mucus, it will be reddish-white in color, accompanied by symptoms such as increased frequency of bowel movement and feeling of falling down in anus. If the blood in the stool is accompanied by infection, the discharged stool will have yellowish-white pus, which mixes with the dark red blood, making the stool appear red, white and yellow. If the bleeding is heavier and faster, the stool is bright red, similar to that caused by ruptured hemorrhoids or anal fissures. Sometimes even from the anus directly discharged a large amount of bright red blood, the patient often appear hemorrhagic shock symptoms, this time the patient can not see the formed fecal sludge stools, often with bright red blood.