Blood in the Stool
The persistent presence of blood in the stool is one of the main symptoms of colon cancer. It may be black, purple, maroon or any other shade of deep red. Since colorectal cancer is an abnormal tissue growth in the large intestine, it can bleed easily and thus show up in the stool.
This is a cause for concern UNLESS you have already received a diagnosis for hemorrhoids (piles), colon inflammation, or bleeding ulcers of the stomach. In case there is no such medical history, you should see a doctor if you have been passing tarry or sticky stool consistently or notice blood when emptying your bowels.
You may be asked to do a fecal test to determine the cause of the abnormal bleeding.