Dr Tom Kennedy describes how guidelines on colorectal cancer designed to improve detection in symptomatic and asymptomatic patients have helped his practice


   

Patients with symptoms suggestive of colorectal cancer (CRC), or with a relevant family history, pose particular management problems for GPs.

It is known that patients often delay before consulting their GP with symptoms such as rectal bleeding, but even when they do consult there can be further delay before the diagnosis is made.

In addition, some patients have a genetic susceptibility to CRC and, although asymptomatic, may report a relevant family history on registering with a practice, or may be identified when a family member is newly diagnosed with CRC.

 

Prognosis in CRC is related to the Dukes' stage at the time of diagnosis. One might therefore assume that prompt detection and therapy may influence outcome, but there have been no studies that directly address the effect of health service related delay.

The outcome in CRC includes the level of morbidity as well as duration of survival, and one of the key features in the management of a patient with CRC is the relationship between the patient and his or her GP. It is the GP who will most likely be involved with care from the time of the patient's first presentation.

As the therapeutic relationship between patient and doctor begins when the patient first consults – or, one could argue, even earlier, when the patient registers with the practice – delays in the process of care place a strain on this relationship. This in turn has a negative influence on the management of the condition, for both doctor and patient.

 

The early detection and management of CRC requires orchestration of services across the primary-secondary care interface. In order to develop guidelines for the early detection of CRC, a panel of GPs, gastroenterologists, clinical geneticists, colorectal surgeons and oncologists participated in a series of consensus meetings during 1998. These were led by Roger Jones, Wolfson Professor of General Practice at Guy's, King's and St Thomas' School of Medicine.

The guidelines were finalised following a review of the research evidence which benefited from the contemporaneous publication of a summary of research evidence relevant to CRC.

Interestingly, many of the factors identified as leading to health service-related delay in primary care were identical to those resulting in delay in secondary care. In addition, it is clear from the studies that only a minority of patients experience primary care-related delays.1

The guidelines (Figure 1) have since been reviewed and endorsed by the Primary Care Society for Gastroenterology and have been circulated to all GPs in the country. They have also been presented internationally at meetings organised by the European Primary Care Society for Gastroenterology.

Figure 1: The guidance on early detection of colorectal cancer in primary care*
guidelines page 1
guidelines page 2
guidelines page 3
guidelines page 4
* Reproduced from The Early Detection of Colorectal Cancer in Primary Care: Guidance for General Practitioners and Health Authorities. Report of a South Thames Working Group, ©GKT Deparment of General Practice and Primary Care 1998

 

I am a GP in an eight-partner general practice in inner-city London. As a partnership, we have agreed to develop or adopt evidence-based management guidelines.

Each partner has a folder in which he or she keeps agreed management guidelines or protocols, and where possible, these are also placed on the practice computer. We are a paperless practice with regard to patient records, and will soon have PC-based workstations on our consulting desks, offering further opportunities for using computerised guidelines as part of clinical governance.

In addition to being a useful aide-mémoire, particularly with regard to genetic aspects of CRC, the guidelines have proved helpful in making clinical decisions.

Studies have shown that doctors seek psychological support and affirmation that a management choice is appropriate,2,3 and I was surprised to find that the guidelines fulfil some of these needs. In particular, the guidelines inform where possible and provide advice where the research evidence is more 'grey' and where the choice of management is unclear.

 

Delay between onset of CRC and presentation to a GP may be the most important factor with regard to clinical outcome, but there is little published work on how best to tackle this delay.

In one population-based study, 12% of people aged more than 50 years in the general population were aware of rectal bleeding in the previous year but only half had consulted a doctor. Patients waited an average of 3 years before seeing their GP, and those who delayed consultation were more likely to consider their symptoms non-serious and not of concern.4

The guidelines do not address the issue of how to reduce patient-initiated delay. Indeed, it is difficult to know how best to influence those symptomatic patients who might benefit from earlier investigation, without so overloading the system with false positives that even greater health service-related delays occur due to delay in accessing secondary care.

The guidelines discuss CRC screening, but a definitive answer to this question awaits a final evaluation of the different screening modalities. Screening asymptomatic patients raises the possibility of detecting CRC in its earliest stages. At present, sigmoidoscopy and faecal occult blood testing are undergoing evaluation, with some published results. Although there is a low rate of complications during an endoscopy procedure, anxieties have recently been raised over the incidence of cardiac events during the weeks after the procedure, a factor that will need to be considered in the overall evaluation of this screening test.

Identifying patients at high risk will be tricky, even if family histories are recorded on the practice computer. We have only recently begun to collect this information, and it requires a considerable investment in IT to enter and search the data, especially in an inner-city area where patient turnover is high.

Attempts are being made to develop software packages that will allow the patient to enter the relevant information from a computer placed, for example, in a booth in the waiting room. This may improve data entry but there are still uncertainties about referring asymptomatic patients for screening and, in particular, the optimal age at which to refer asymptomatic patients with a family history of CRC.

Personally, I have found the guidelines most helpful in the management of symptomatic patients, and in offering guidance on how to advise patients with a family history of CRC. They have also given me an indication of what is required in order to prioritise cases for referral to secondary care and what to expect from secondary care in return.

 

  1. Hughes GS, McDermott FT, Masterton JP. Delayed diagnosis of carcinoma of the rectum and sigmoid. Aust NZ J Surg 1979; 49(4): 432-3.
  2. Smith R. What clinical information do doctors need? Br Med J 1996; 313; 1062-8.
  3. Forsythe DE, Buchanan BG, Osheroff JA, Miller RA. Expanding the concept of medical information: an observational study of physicians' information needs. Comput Biomed Res 1992; 25: 181-200.
  4. Crosland A, Jones R. Rectal bleeding: prevalence and consultation behaviour. Br Med J 1995; 311: 486-8.

Guidelines in Practice, November 1999, Volume 2
© 1999 MGP Ltd
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