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Colorectal cancer

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Symptoms of colorectal cancer

Colorectal cancer may not cause any signs or symptoms in its early stages because the cancer is very small. Symptoms often appear once a tumour grows into surrounding tissues and organs. Other health conditions can cause the same symptoms as colorectal cancer.

See your doctor if you have these symptoms:

  • diarrhea
  • constipation
  • stool that looks narrower than usual
  • feeling like the bowel is not completely empty after a bowel movement
  • blood in the stool (it can be bright or very dark red)
  • bleeding from the rectum
  • gas, cramping, bloating and feeling full
  • pain or discomfort in the rectum
  • a lump in the abdomen or rectum
  • fatigue and weakness
  • anemia, which may cause fatigue and shortness of breath
  • nausea and vomiting
  • loss of appetite
  • weight loss
  • blockage in the intestine (called bowel obstruction), which may cause pain in the abdomen
  • a tear or hole in the intestine (called bowel perforation), which may cause widespread infection (called sepsis)
  • frequent urinary tract infections
  • swollen lymph nodes
  • enlarged liver (called hepatomegaly)
  • jaundice (a condition in which the skin and whites of the eyes become yellow and urine is dark yellow)
  • buildup of fluid in the abdomen (called ascites)
  • pain in the abdomen, buttocks or leg
  • breathing problems

Stories

Parker Murchison My favourite thing about Camp Goodtime is being able to hang out with other kids who have survived cancer. They know what is going on in your life and can help you get through it.

Read Parker's story

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