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Early identification of bowel cancer in the community: the role of online symptom checkers

- The need to identify patients who can be safely managed in the community and those who need urgent referral

 - The role of online symptom checkers and how these can aid patients and nurses

 - Reassuring patients who do not have bowel cancer and offering treatment for their bowl symptoms


New findings on the typical symptoms, signs and secondary effects of patients with bowel cancer form the basis for building an online bowel symptom checker to improve the management of patients with these symptoms. The symptom checkers have now been adopted by NHS Choices.

These new studies1-9 have shown that over 95% of bowel cancers have at least one of three symptom combinations, one of its two physical signs or one of its three secondary effects. This means that systematic identification or exclusion of these characteristics not only identifies virtually all patients with cancer, it also identifies patients who at very low risk of cancer who can be safely managed without immediate referral to hospital.

The need for a bowel symptom checker

The complexity of the inter-relationship between the symptoms signs and secondary effects of bowel cancer

Bowel cancers can present with a seemingly infinite number combinations of its symptoms, signs and secondary effects, all with varying predictive values indicating the risk of having cancer. Although the information required can be collected on the basis of a structured history, simple clinical examination and a blood test, online decision support will ensure all the most important diagnostic criteria are collected to achieve reliable risk stratification.

The burden and cost of bowel cancer diagnosis

Bowel cancer is the second most common cause of cancer-related deaths in the UK.10 If the disease is detected in its early stages, the successful treatment rate is quite high at 90%. Unfortunately, only 40% of bowel cancer cases are detected in the early stages.

Almost 30% of the total budget for bowel cancer in the UK is spent on investigation and diagnosis, and because of the inefficiencies of the current way we manage people with bowel symptoms, 93% of the budget for diagnosis is spent on those who turn out not to have cancer.2

The high prevalence of bowel symptoms

Bowel symptoms are very common in the general population.13,14 Each year, over 7 million people in the UK have rectal bleeding, with 99.9% of them not having a serious bowel problem. If all these patients, together with those who had a change in their bowel habit, constipation, diarrhoea and abdominal pain, went to seek GP advice, the burden on the primary care services would be immense. Fortunately, the majority of people in the UK manage their symptoms quite appropriately in the community without medical advice.14,15 However, as awareness of the importance of these symptoms increases,16 those in the community will need access to reliable information to help them decide whether they should see their GP immediately or wait and see if the problem resolves itself.

Current delays in diagnosis of bowel cancer and its possible effect on survival

One in ten patients with bowel cancer have a delay in diagnosis of over a year and 30% over six months.17 Much of this is due to patient delay17 as often people are unaware of the significance of their symptoms, which do not make them feel ill. There has been no reduction in delay over the last 60 years17 and new methods need to be tried if any reduction in the delay is to be achieved in the future.

Danger of invasive investigations

There is a small unavoidable risk of investigation including the hidden costs of time off work for the patient and their relatives and the worry incurred. Colonoscopy particularly in the elderly carries the risk of sedation and bowel preparation and CT scans carry the risk of false positives, resulting in unnecessary investigations and surgery. This means in low risk patients investigations may do more harm than good and consume expensive resources that may be better directed to screening.  

Requirements of a symptom checker

Risk stratification

An individual's`sk of having bowel cancer in the community is dependent on the prevalence of the symptom in the community3,14 as well as its prevalence in bowel cancer patients.3 Risk stratification on the basis of symptoms alone has been shown to be effective.19

The estimates of risk used for the symptom checker for patients in the community were based on the findings of a number of peer-reviewed studies1,4,5,6 and abstracts7-9 on subsets of 29,005 patients seen in Portsmouth in out-patient clinics over the past 25 years.

Appropriate periods of 'waits' in 'treat, watch and wait' diagnostic strategies

Can a short delay in diagnosis harm?

Risk stratification needs to guide a selection of patients for prompt referral or 'treat, watch and wait' diagnostic strategies. These diagnostic strategies are based on the assumption that patients with symptoms from benign conditions are self-limiting while those with cancer are persistent.

Do short delays in treatment do harm?

The findings of a large review18 found little evidence that earlier diagnosis of bowel cancer is beneficial, which suggests the 'die is cast' in
terms of survival for many patients during its long pre-symptomatic natural history. This means that further short delays during 'treat, watch and wait' diagnostic strategies have very little effect on the chances of completely removing the cancer.

Advice on simple treatments of symptoms

An integral part of reassuring patients with bowel symptoms is to provide a credible alternative cause for their symptoms and advise on potentially effective treatments for these benign conditions.4 This information can be included in online advice. It is also important to make clear that if simple treatments are ineffective and their symptoms persist, regardless of their nature, patients will need to see their GP. The symptom checker incorporates this golden rule into the advice given.

Provide a printed summary of the patient's symptoms if they see their GPs

The checker at provides a printed summary of their current symptoms and the advice they have been given to take to their GP. It also includes information that their GP will achieve further risk stratification by simple examinations of their abdomen and rectum and a blood test to see if they have iron deficiency anaemia.


Over 7 million people have rectal bleeding in the UK each year and even more have a change in bowel habit and abdominal pain. A third to a half of all bowel cancers have a delay in diagnosis of over six months and there is little evidence of improvement over the last 60 years.

The UK Department of Health has introduced public awareness campaigns and the National Institute of Health and Care Excellence (NICE) GP referral guidelines to reduce delay in diagnosis, which may be an important cause for poor survival from bowel cancer in the UK.

These strategies can result in unnecessary worry for many people without cancer, high referral rates to hospital, over investigation and high costs to the healthcare system with little direct evidence of benefit to those with bowel cancer. There is a need to improve the efficiency as well as effectiveness of management of the very large number of patients presenting with symptoms suggestive of bowel cancer.

Online symptom bowel symptom checkers now provide the hope that some progress can be achieved in the difficult process of promptly diagnosing those with bowel cancer without over referral and investigation of the much larger group of patients without cancer.


1.    Ellis BG, Thompson MR. Factors identifying higher risk bleeding in general practice. Br J Gen Pract 2005;55(521):949-55.
2.    Flashman K, O'Leary DP, Senapati A, Thompson MR. The Department of Health's 'two-week standard' for bowel cancer: is it working? Gut 2004;53(3):387-91.
3.    Association of Coloproctology of Great Britain and Ireland European Association of Coloproctology. National referral guidelines for bowel cancer. Colorectal Dis
4.    Thompson MR, Heath I, Ellis BG, Swarbrick ET, Faulds Wood L, Atkin WS. Identifying and managing patients at low risk of bowel cancer in general practice. BMJ 2003;327(7409):263-5.
5.    Thompson MR, Perera R, Senapati A, Dodds S. Predictive value of common symptom combinations in diagnosing colorectal cancer. Br J Surg 2007;94(10):1260-5.
6.    Thompson MR, Flashman KG, Wooldrage K, et al. Flexible sigmoidoscopy and whole colonic imaging in the diagnosis of cancer in patients with colorectal symptoms. Br J Surg 2008;95(9):1140-6.
7.    Branagan G, Senapati A, Thompson MR, O'Leary DP. Dark vs bright red bleeding in the diagnosis of colorectal cancer. Colorectal Dis 2004;6(Suppl 1):47.
8.    Chave H, Flashman K, Cripps NPJ, Senapati A, Thompson MR. The relative values of the characteristics of rectal bleeding in the diagnosis of colorectal cancer. Colorectal Dis 2000a;2(Supple 1):1/01.
9.    Chave H, Flashman K, Senapati A, Cripps NPJ, Thompson MR. Characteristics of the change in Bowel Habit in Patients with Colorectal Cancer. Colorectal Dis2000b;2(Suppl 1):1-2.
10.    Cancer Research UK. Bowel Cancer. Cancer Statistics Key Facts. 2013.
11.    NHS Choices Bowel Cancer: Overview.
12.    York Health Economics Consortium. Bowel Cancer Services: Costs and Benefits. Final Report to the Department of Health. 2007.
13.    Swan E, ed. Colorectal Cancer. London; Whurr Publishers Ltd: 2005.
14.    Thompson JA, Pond CL, Ellis BG, Beach A, Thompson M. Rectal bleeding in general and hospital practice; 'the tip of the iceberg'. Colorectal Dis 2000;2(5):288-93.
15.    Crosland A, Jones R. Rectal bleeding: prevalence and consultation behaviour. BMJ 1995;311(7003):486-8
16.    Department of Health. Bowel cancer awareness campaign to go national. 2011
17.    Thompson MR, Heath I, Swarbrick ET, Wood LF, Ellis BG. Earlier diagnosis and treatment of symptomatic bowel cancer: can it be achieved and how much will it improve survival? Colorectal Dis 2011b;13(1):6-16.
18.    Thompson MR, Asiimwe A, Flashman K, Tsavellas G.Is earlier referral and investigation of bowel cancer patients presenting with rectal bleeding associated with better survival? Colorectal Dis 2011a;13(11):1242-8.
19.    Selvachandran S, Hodder R, Ballal M, Jones P, Cade D. Prediction of colorectal cancer by a patient consultation questionnaire and scoring system: a prospective study. Lancet 2002;360(9329):278-83.
20.    http://bit. ly/1bl7fEC" target="_blank">NHS Choices Bowel Cancer self-assessment.