Around one in five bowel cancer patients diagnosed after an emergency presentation have displayed at least one cancer 'alarm symptom' in the year leading up to their diagnosis, according to a Cancer Research UK-funded study published in the British Journal of Cancer.

The study found that 'red flag' symptoms were much more common in patients who were diagnosed via non-emergency routes, and that patients diagnosed as an emergency often did not display these symptoms strongly associated with bowel cancer.

It's lack of these 'red flag' symptoms in many patients diagnosed as an emergency that makes it much more difficult for GPs to diagnose the cancer early.

But a proportion of patients - 17.5 per cent of colon cancer patients and 23 per cent of rectal cancer patients diagnosed as an emergency - had 'red flag' symptoms, indicating there could have been opportunities to pick up the disease earlier.

Most patients, regardless of how they were diagnosed, visited their doctor in the year before their diagnosis. And patients saw their doctors more often in the months and days leading up to their diagnosis, with the number of visits increasing significantly both for patients diagnosed by emergency and non-emergency routes.

The study, at University College London and the London School of Hygiene & Tropical Medicine, looked at National Cancer Registry data that was linked to GP data for 1,606 patients across more than 200 GP practices. The research focused on patient data for the five years leading up to the cancer diagnosis.

Cristina Renzi, lead researcher, Cancer Research UK scientist at University College London, said: "We know that patients diagnosed with cancer after emergency presentations don't do as well as patients who are diagnosed by their doctor through non-emergency routes. This study shows that most patients - who are picked up through the emergency route - can be harder to diagnose as they often don't show typical bowel cancer symptoms. However, in most cases they visit their doctor for various reasons multiple times during the months leading up to their diagnosis, which could represent opportunities to diagnose the cancer earlier.

"It's important to find ways to ensure these patients can be diagnosed at an early stage. And this study highlights the need to support GPs and give them the tools to diagnose and refer patients promptly when they feel it's necessary."

Dr Julie Sharp, Cancer Research UK's head of patient information and health, said: "This research shows the difficulties in diagnosing patients who are not showing typical symptoms of bowel cancer. In some cases where people have been diagnosed after an emergency presentation, there may have been opportunities for people to be diagnosed earlier, and it's important to try to find better ways of picking up these patients and getting them referred appropriately.

"So research like this, to understand more about people's symptom histories, is crucial to find better ways to diagnose the disease at an early stage when treatment is more likely to be successful."

Article: Do colorectal cancer patients diagnosed as an emergency differ from non-emergency patients in their consultation patterns and symptoms? A longitudinal data-linkage study in England, Renzi et al., British Journal of Cancer, doi:10.1038/bjc.2016.250, published online 18 August 2016.