■ Safety of care:

Improving patient safety and reducing risks

Early detection of colorectal cancer can help save a patient’s life

7 minutes

Published: December 2019

The information in this article was correct at the time of publishing

Managing the cycle of ordering, receiving, reviewing, and communicating diagnostic investigations is an essential part of any clinical practice, and when this process breaks down, diagnostic delays or errors can result, putting patients at risk for harm.

26% favourable medical-legal outcome, 74% unfavourable medical-legal outcome
Figure 1: Distribution of CMPA cases by medical-legal outcome, 2014-2018 (n=119).

This concern is especially true when it comes to improving survival rates for colorectal cancer. A delay in colorectal cancer diagnosis poses a risk that the disease will be identified only at a later stage, significantly reducing a patient’s likelihood of survival. According to the Canadian Cancer Society, the “five-year relative survival for colon cancer is estimated to be 92% for cancers diagnosed at stage I compared with only 11% for stage IV; five-year survival for rectal cancer is estimated to be 87% for stage I and 12% for stage IV.”1

The CMPA’s analysis of 119 cases (43 legal actions, 71 College cases, and 5 hospital complaint cases) that closed between 2014-2018 involving a delayed diagnosis of colorectal cancer reveals that 74% resulted in an unfavourable medical-legal outcome (Figure 1). This means that the case was settled on behalf of the member, or resulted in a court judgment against the member, or had a finding by the College or hospital that the physician’s care fell below expectations. Recurring allegations in these cases include cognitive biases of physicians ordering tests, lack of robust test follow-up systems, and breakdowns in communicating with patients.

Screening programs—Understanding expectations

Cancer organizations across the country recommend administering specific screening tests to detect colon cancer.2 Although not mandatory, these recommendations may influence the standard of care that regulatory authorities (Colleges) and the courts would expect physicians to follow. If a patient safety incident is found to stem from a physician’s failure to follow accepted guidelines, this may be part of the evidence used to find the physician breached the standard of care.

Case example: Changes in primary care provider leads to a missed cancer diagnosis3

A woman in her 40s sees her new family physician for the first time. She requests a prescription renewal for a hemorrhoid cream that had been prescribed by her previous family physician for persistent rectal bleeding. She shares that she had been diagnosed with hemorrhoids and had recently undergone a barium enema, which was negative for colorectal cancer. While the new family physician does not perform a digital rectal exam, he renews the prescription and requests the patient’s records from the previous family physician. The medical record confirms normal results from the barium enema, and also shows that a follow-up colonoscopy had been recommended due to incomplete bowel imaging. Nevertheless, the new physician does not review the patient’s records and does not order the colonoscopy.

Months later, during a visit to an urgent care clinic, the patient is concerned about bright red blood and mucus in her stool. The urgent care physician orders a flexible sigmoidoscopy and a barium enema that ultimately reveal the presence of stage T2 adenocarcinoma in the rectum. The patient undergoes chemotherapy and radiation treatments, and files a legal action against the family physician, alleging a delay in diagnosis.

What the experts said

Experts were not supportive of the family physician's care in this case, stating that he should have confirmed the presence of hemorrhoids sooner through a physical exam, and then pursued further investigations. They determined that had the delay in diagnosis not occurred, the cancer would have only required surgery, and not chemotherapy and radiation. The CMPA settled the case on behalf of the family physician.

Ordering tests

There are many points during test follow-up where process breakdowns can occur, including when deciding whether to order the test itself.

When presented with symptoms of blood in stool in an otherwise healthy young woman, and having been told that hemorrhoids had already been diagnosed, the experts reviewing the physician’s care in the case above found that he anchored to the diagnosis of hemorrhoids without having confirmed their presence himself. This could have been done through a digital rectal exam and other investigative methods, such as a sigmoidoscopy. (The predictive value of barium enema has been scrutinized as a diagnostic tool for colorectal cancer, as studies have found it to have a miss rate of 17% in detecting colorectal cancer.4) Anchoring—when one focuses “on one particular symptom, sign, or piece of information, or a particular diagnosis early in the diagnostic process and fail[s] to make any adjustments for other possibilities”5 —is a form of cognitive bias that can hinder or delay an accurate diagnosis.

A delay or failure in the performance of a diagnostic test or therapeutic intervention was identified in 34 (29%) of the CMPA cases analyzed.6

Risk reduction strategies

  • When treating a new patient with a previous diagnosis, consider whether it is appropriate to reassess and confirm the diagnosis prior to providing treatment.
  • In addition to performing a comprehensive history, consider whether it is appropriate to perform a physical exam. Be sure to review your new patients’ prior records.
  • Re-evaluate the diagnosis when symptoms persist, where appropriate.

Receiving and reviewing test results

During the multiple phases of test follow-up, requisition forms can be lost, specimens can be mislabeled, and test results may not be returned, among other possible process breakdowns.

In the above case, the need for a follow-up colonoscopy was noted in the medical record, though this went unnoticed by the new family physician and was not communicated to him during the handover of patient records.

Several cases in the CMPA analysis highlighted system failures, including lost or mislaid reports or results, mishandled diagnostic tests, and issues with administrative policies or procedures. These failures were identified in 16 cases (13%).

Risk reduction strategies

  • Review College policies to ensure compliance with expectations to employ an appropriate system for follow-up of test requisitions and results, including suspicious, indeterminate, or discrepant findings.
  • When your patient changes to a new care provider while there are still pending tests that require follow-up, discuss with the patient how best to communicate this information to the new provider.
  • Review your administrative office procedures to identify possible weaknesses in your test follow-up process.

Communication breakdown

Patients may not follow through with diagnostic testing for many reasons, such as not understanding the need for the investigation, forgetting, being too busy, or feeling afraid of the findings.

In the above case, a communication breakdown occurred between the family physicians and the patient. The patient did not remember having been told by her previous physician that she would need a follow-up colonoscopy, so she did not mention it during the initial consultation with her new physician. As well, when having previously received treatment for hemorrhoids, the patient may not have understood why it was important for her new physician to conduct his own assessment and was therefore reluctant about it.

In the CMPA analysis, a communication breakdown between physicians was identified as a contributing factor in 11 cases (9%), while a communication breakdown between patients and their physicians was identified as a factor in 24 cases (20%).

Risk reduction strategies

  • Confirm that the patient understands the information you provide, and answer questions honestly and openly. If further testing is required, educate the patient on the necessary timelines and risks if the test is not performed.
  • Communicate to the patient the purpose of each test ordered, including the need for more testing if appropriate. Recognize that uncomfortable tests may require you to do more follow-up.
  • Document discussions with patients regarding test follow-up or further necessary testing. If a patient declines further testing, explore the patient’s concerns and document the conversation.

The bottom line

Based on the expert opinions in the cases reviewed, the suggested risk reduction strategies may be suitable in your practice. Consider also the following suggestions:

  • Adopt strategies to identify and mitigate your cognitive biases.
  • Consider ways to assess and improve your processes for following up on diagnostic testing.
  • Communicate openly with patients to assess, and if necessary improve, their understanding of the importance of diagnostic testing and cancer screening.




  1. Canadian Cancer Statistics Advisory Committee [Internet]. Canadian Cancer Statistics 2018. Toronto(CA): Canadian Cancer Society;2018 June [cited 2019 August]. Available from: www.cancer.ca/Canadian-Cancer-Statistics-2018-EN
  2. Canadian Task Force on Preventive Health Care. Recommendations on screening for colorectal cancer [Internet]. CMAJ. 2016 March [cited 2019 August];188 (5): 340-348. Available from: 10.1503/cmaj.151125
  3. While based on a real case, some facts in this case scenario have been altered to protect patient and physician confidentiality.
  4. Shariff, M, Sheikh K, Carroll N, et al. Colorectal cancer detection: time to abandon barium enema? Frontline Gastroenterology [Internet]. 2011 [cited 2019 September]; 2(2):105-109. Available from: http://dx.doi.org/10.1136/fg.2010.003616
  5. Canadian Medical Protective Association [Internet]. Ottawa (CA):CMPA. CMPA Good Practices Guide. Common Cognitive Biases [cited 2019 August]. Available from: https://www.cmpa-acpm.ca/serve/docs/ela/goodpracticesguide/pages/human_factors/Cognitive_biases/pdf/hf_common_cognitive_biases-e.pdf
  6. This insight was obtained using the CMPA’s Contributing Factor Framework. For more information see: McCleery A, Devenny K, Ogilby C, et al. Using medicolegal data to support safe medical care: A contributing factor coding framework. Journal of Healthcare Risk Management [Internet]. 2018 August 3 [cited 2019 August]; 38(4):11-19. Available from: https://doi.org/10.1002/jhrm.21348

DISCLAIMER: The information contained in this learning material is for general educational purposes only and is not intended to provide specific professional medical or legal advice, nor to constitute a "standard of care" for Canadian healthcare professionals. The use of CMPA learning resources is subject to the foregoing as well as the CMPA's Terms of Use.