Colon Cancer | Early Warning Signs & Stages of Colon Cancer

4) Blood in the Stools

Blood in the stools is one of the most common and characteristic signs of colon cancer. As the tumor grows in size, it tends to put pressure on the surrounding tissues, including the nerves and blood vessels. Damage to these delicate blood vessels results in hemorrhage and bleeding. The blood in the stools is either red and fresh or black and foul-smelling. Red blood indicates that the bleeding point is somewhere near the anus. In the majority of cases, blood will be visible to the naked eye while in some cases it may only be seen under a microscope. The amount of blood in the stool depends on the location, tumor size, and severity of the disease.

If you have dark feces or blood clots in the stools, it can be due to some other gut condition such as stomach or duodenal ulcers. Blood clots indicate a remote position from the anus.

Sometimes, blood clot also forms in colorectal cancer because of the secondary changes in the gut such as bowel obstruction or constipation. These conditions enable the large intestine to hold stools for a long period of time and may lead to dark-brown or cola-colored stools. Therefore, it is important to consult your health care provider to evaluate and diagnose the underlying cause of your bleeding. Your doctor will examine the stool sample under a microscope, perform a fecal occult test and do additional examinations such as colonoscopy to determine the source of the blood.