Colorectal Cancer

Symptoms and diagnosis of bowel (colorectal) cancer

“Bowel (colorectal) cancer is the 4th most common cancer in the UK after breast, lung and prostate cancer. In the UK around 41,900 people are diagnosed with bowel cancer each year.” Cancer Research UK January 2016

  • Some of the symptoms of bowel (colorectal) cancer are:
  • blood in the stools,
  • a persistent change in bowel habit,
  • unexplained weight loss,
  • unexplained tiredness,
  • anaemia,
  • pain in the stomach (abdomen) or back passage,
  • pain, discomfort or bloating after eating and a
  • a feeling that the bowels have not been entirely emptied.

These symptoms do not always mean a person has bowel (colorectal) cancer as they can also be symptoms of other, less serious illnesses. It is possible to have some rather than all the symptoms, or to have the disease for some time without noticing any symptoms at all. This makes it hard to decide when to see a doctor. It also makes it hard for a doctor to know when to refer someone for further investigations. NICE – National Institute for Health and Care Excellence has produced guidelines which help GP’s make decisions about when to refer people to specialists when they present with symptoms that could be caused by cancer.

People who do not have classic symptoms or who are considerably younger than average when they develop the disease often experience misdiagnoses and delayed treatment. 

Some people are slow to seek attention because they feel unhappy about discussing their bowels or the prospect of an embarrassing examination. Some are simply frightened of what might happen. This woman explains how she delayed taking up her GPs referral until her daughter insisted on it.

Another woman, who had seen a consultant once, felt embarrassed to go again about worsening symptoms. Many people assumed at first that their symptoms were due to stress, travel, or a change of diet. One man (see below) lists the many reasons he came up with to explain what was happening to him. 

The symptom that most often prompted people to see their doctor was rectal bleeding which could be slight or occasional or heavy and persistent. One man describes what he experienced and his GP's prompt response. Other people who received quick and appropriate attention from their GP's were invariably grateful. Other people were frequently misdiagnosed with piles (haemorrhoids) or irritable bowel syndrome. Some people were treated for constipation or diarrhoea for as long as 15 months before further investigations were pursued. A young woman whose symptoms developed while she was pregnant was offered a series of explanations and eventually realised what was wrong herself when she saw something about bowel cancer on the television.

Sometimes delayed diagnosis was unavoidable. One man underwent numerous tests over a period of 18 months but needed surgery to confirm his diagnosis because his tumour was 'hidden' and extremely difficult to detect by other means. 

Other people, and especially those who rarely went to the doctor, felt that delays had occurred because their GP or consultant had not acknowledged the persistence or severity of their symptoms or they were simply not being believed. A woman who felt that her consultant did not believe her started taking someone with her to appointments 'so as they could hear what he was saying'. A man, who was in 'a terrible state' with vomiting and severe constipation, saw two different GPs who did not connect his symptoms to bowel cancer. His son took him to hospital where he had surgery a few days later. Stephen had experienced six months of symptoms and many visits to his GP and A&E before being diagnosed.

Some patients felt that GPs were not communicating effectively with each other, or making effective use of medical records. One man believed that he had not been referred promptly for further investigation because of the cost. In a number of cases, difficulties reaching a diagnosis led to the breakdown of relations between doctor and patient.

The advice consistently offered by patients to others experiencing possible symptoms of bowel cancer was to seek immediate medical attention, to trust their instincts and to insist on further investigation if the problem persists and they still feel that something is wrong.

In England, Wales and Northern Ireland the NHS Bowel Cancer Screening Programme offers screening every two years to all men and women aged 60-74. The national bowel screening programme in Scotland screens men and women aged between 50 and 74 years (Scottish Bowel Screening Programme). Bowel cancer screening is an important way of finding bowel cancers early, when they are small and there are no symptoms. See our Bowel Screening website for more information.
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Last reviewed August 2016.

Last updated August 2016.


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