Many bowel cancer patients are first diagnosed in an emergency setting, when they have severe and potentially life-threatening conditions, figures show.
There are 29,000 bowel cancer patients diagnosed each year in England and Wales. One in five of these is admitted as an emergency, according to the National Bowel Cancer Audit.
Nearly a third of those diagnosed through the emergency route were not offered surgery because their cancer was already too advanced to be operated on.
The proportion of bowel cancer patients who die following major surgery has fallen for the fourth consecutive year.
But more patients operated on in an emergency died within 90 days of having surgery (11.9 per cent) compared with the number of all bowel cancer patients who died within 90 days of surgery (5.1 per cent).
More needs to be done to raise awareness about the disease to ensure more people are diagnosed earlier, say experts.
Nigel Scott, the consultant colorectal surgeon at the Royal Preston Hospital who led the audit, said: "Bowel cancer emergency admissions are a persistent and very significant health problem.
"Symptom awareness campaigns are useful to break down the taboos of bottoms and bowels that lock these symptoms behind the bathroom door. But emergency surgery continues to be the Cinderella of surgical practice in the UK."
He also said that a recent survey of surgeons highlighted that "NHS pressures currently work against emergency cases, with 55 per cent of surgeons describing inadequate emergency theatre access."
Sarah Woolnough, Cancer Research UK's director of policy, said: "This report confirms that too many people are being diagnosed with bowel cancer through an emergency hospital admission, and at a stage when treatment is less likely to be successful. This underlines the importance of knowing the potential symptoms of bowel cancer, such as loose stools or blood in your stools, as there's a better chance of surviving the disease if it's diagnosed earlier.
"Raising awareness about bowel cancer symptoms could also encourage people to take up their invitation for bowel screening and improve early detection of the disease."
Source: CRUK