Bowel cancer symptoms
In its early stages, bowel cancer may have no symptoms. This is why screening is important to increase the chance of an early diagnosis. However, many people with bowel cancer do experience symptoms. These can include:
- blood in the stools or on the toilet paper
- a change in bowel habit, such as diarrhoea, constipation or smaller, more frequent bowel movements
- a change in appearance or consistency of bowel movements (e.g. narrower stools or mucus in stools)
- a feeling of fullness or bloating in the abdomen or a strange sensation in the rectum, often during a bowel movement
- feeling that the bowel hasn’t emptied completely
- unexplained weight loss
- weakness or fatigue
- rectal or anal pain
- a lump in the rectum or anus
- abdominal pain or swelling
- a low red blood cell count (anaemia), which can cause tiredness and weakness
- rarely, a blockage in the bowel.
Not everyone with these symptoms has bowel cancer. Other conditions, such as haemorrhoids, diverticulitis (inflammation of pouches in the bowel wall) or an anal fissure (cracks in the skin lining the anus), can also cause these changes. Changes in bowel function are common and often do not indicate a serious problem. However, any amount of bleeding is not normal and you should see your doctor for a check-up.
Download a PDF booklet on this topic.
A/Prof Craig Lynch, Colorectal Surgeon, Peter MacCallum Cancer Centre, VIC; Prof Tim Price, Medical Oncologist, The Queen Elizabeth Hospital, Adelaide, and Clinical Professor, Faculty of Medicine, The University of Adelaide, SA; Department of Dietetics, Liverpool Hospital, NSW; Dr Hooi Ee, Gastroenterologist, Sir Charles Gairdner Hospital, WA; Dr Debra Furniss, Radiation Oncologist, Genesis CancerCare, QLD; Jocelyn Head, Consumer; Jackie Johnston, Palliative Care and Stomal Therapy Clinical Nurse Consultant, St Vincent’s Private Hospital, NSW; Zeinah Keen, 13 11 20 Consultant, Cancer Council NSW; Dr Elizabeth Murphy, Head, Colorectal Surgical Unit, Lyell McEwin Hospital, SA. We also thank the health professionals, consumers and editorial teams who have worked on previous editions.
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