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Signs & Symptoms

The early signs of colorectal cancer can mimic symptoms caused by other gastrointestinal illnesses, such as influenza, ulcers, and colitis (an inflammation of the colon). If any of the following symptoms last more than two weeks, however, it is important to see a physician for an evaluation:

  • Unexplained persistent diarrhea or constipation.
  • Blood in or on the stool (can be bright red or very dark).
  • Narrower stools than usual.
  • Unexplained iron deficiency anemia.
  • Intermittent abdominal pain.

The following symptoms can be signs of rectal cancer:

  • Blood in the stool.
  • Diarrhea.
  • A sense of bowel movement urgency.
  • Feeling of inadequate emptying of bowel.
  • Excessive straining to have a bowel movement without passing of stools.