Safety of care

Improving patient safety and reducing risks

Failure to make the diagnosis of colorectal cancer: A window of opportunity missed

Originally published September 2008

Of interest to all physicians

In Canada, colorectal cancer is a common form of cancer and the second leading cause of death from cancer1. Screening of asymptomatic patients to remove polyps, a precursor of cancer, and early diagnosis of symptomatic patients are considered important in decreasing the risk of death from colorectal cancer.

This medico-legal case review looks at patients who were both asymptomatic and symptomatic of the disease, although the focus is on the diagnosis of patients with symptoms on initial assessment.

The review identifies six areas associated with potential delays in the diagnosis of colorectal cancer:
1) history and physical examination, including digital rectal examination
2) ordering of appropriate investigations
3) follow up of planned investigations
4) interpretation of test results
5) referral processes
6) communications between physicians and with patients.

The following three cases of symptomatic patients highlight these areas of risk.

1Canadian Cancer Society/National Cancer Institute of Canada: Canadian Cancer Statistics 2008. Toronto, Canada, April 2008, ISSN 0835-2976. Last accessed August 2008.

Case #1: Failure to adequately examine a symptomatic patient

A 64-year-old woman was seen by her family physician complaining of a recent change in bowel habit— bouts of diarrhea, with no associated rectal bleeding, abdominal pain, or weight loss. Examination of her abdomen revealed no masses or tenderness. A digital rectal examination was not done. A barium enema was requested to rule out diverticular disease or malignancy.

At the time of the barium enema, the radiology technician had difficulty introducing the cannula and explained to the patient, who was quite uncomfortable, that this was likely because of the presence of prominent hemorrhoids. One week later, the patient was told the barium enema was normal. The patient informed her physician that the technician had difficulty introducing the cannula, and this was again attributed to the hemorrhoids. She clearly informed her family physician of her continuous rectal pain and now intermittent ano-rectal bleeding. On a presumptive basis, without a digital rectal examination, she was prescribed suppositories and sitz baths.

One month later she revisited her family physician with the same symptoms. Her therapy was not changed. A follow up was scheduled for a month from that visit.

One month later, her symptoms were worsening and a digital rectal examination revealed an abnormal fullness. She was immediately referred to a general surgeon. The surgeon who saw her in consultation two days later reported a large ulcerating tumour within easy reach of the examining finger. Malignancy was confirmed and she had appropriate oncology treatment including chemotherapy and radiation therapy.

The patient initiated a complaint to the regulatory authority (College) alleging a delay in the diagnosis of cancer. Although she subsequently withdrew her complaint, the College completed its assessment of the care. The family physician was asked to attend the College to be cautioned. The College stated the physician, when faced with continuing complaints of this sort, should have performed a digital rectal examination.

Case #2: Delay in the investigation of a symptomatic patient

A 75-year-old woman on non-steroidal antiinflammatory drugs (NSAIDs) for osteoarthritis presented to her family physician with anorexia, fatigue and intermittent diarrhea. Blood work showed a haemoglobin (Hgb) of 98 gm/L, mean cell volume (MCV) 82 and ferritin 5 ng/ml. The family physician attributed the results to poor nutritional intake, and therefore prescribed iron supplements.

During the ensuing months, the patient was seen frequently for other problems. A repeat hemoglobin five months after her initial visit improved to 124 gm/L, but her ferritin remained low at 7 ng/ml. The cause of her iron deficiency was not investigated.

Blood work at nine months revealed a Hgb of 108 gm/L. A barium enema was subsequently ordered revealing a caecal mass lesion, later confirmed by biopsy to be adenocarcinoma. There was no record of performing a digital rectal examination and checking for fecal occult blood.

The family initiated a complaint to the College alleging a delay in diagnosis. The College concluded "the possibility of chronic blood loss as a result of a malignancy was not ruled out" and was critical of the care.

Case #3: The limits of investigations, communication issues and delay in followup

A family physician referred a 52-year-old male to an endoscopist for investigation of an iron deficiency anemia and occult blood in the stools. A colonoscopy was performed. Visualization was only achieved to the level of the mid-transverse colon and the procedure was terminated due to patient discomfort. The patient was advised to see the endoscopist in follow up, but no appointment was given to the patient.

Three weeks later, the endoscopist dictated a note stating his intention to arrange a barium enema to ensure there is no bleeding from the right side of the colon.

The patient did not attend for a follow up as he had not received the appointment for the barium enema and he believed the endoscopist wanted the test done prior to seeing him. The endoscopist presumed the patient had opted to follow up with the family physician and made no further enquiries.

During an unrelated visit with his family physician six weeks later, the patient mentioned that no date had been set for a follow up with the consultant endoscopist. The family physician recorded the inadequacy of the colonoscopy and the recommendation for a barium enema, but assumed ordering it would be the responsibility of the consultant.

Seven months after the colonoscopy, the patient returned to his family doctor complaining of cramping abdominal pain and was referred to a general surgeon. A repeat colonoscopy revealed an obstructing and bleeding mass of the right colon, and biopsy confirmed adenocarcinoma. The patient underwent a right hemicolectomy for a locally invasive cancer. After a course of chemotherapy, the patient developed a major depression requiring psychiatric care. He started a legal action alleging the seven-month delay in the diagnosis allowed the cancer to progress and metastasize to lymph nodes.

Experts were not supportive of the care given by either the family physician or the endoscopist:

  • Endoscopist expert – "…with the referral and subsequent to the incomplete colonoscopy, the onus of responsibility specific to investigations, including the barium enema, was the primary and direct responsibility of the consultant."
  • Family physician expert – "…the (FP) owed a duty of responsibility, given the time frame of the test not being done, to ensure that this test had been requisitioned or to direct the patient to contact the consultant. Failure to pursue either option falls below the standard of care."

Lacking expert support, a settlement was paid to the patient by the CMPA on behalf of both member physicians.

CMPA data

A review of the Association's closed cases from 1997 to 2006 related to a delay in diagnosis of colorectal cancer revealed 90 complaints to the Colleges and 68 legal actions, and some were both. Figure 1 provides the distribution of specialties of physicians involved.

Figure 1: The distribution of specialties of physicians found responsible for delays in

It is important to recognize that the physicians determined to be responsible for a delay in the diagnosis of colorectal cancer had various specialties.

Case outcomes

Figure 2: Outcome of College complaint cases

The Colleges expressed concerns relating to a delay in diagnosis in nearly half the cases.

Figure 3: Outcome of legal cases

In 47 per cent of the legal cases, the patient received compensation from the CMPA on behalf of the member physician. This percentage is higher than the overall CMPA experience (Figure 4).

Figure 4: The medico-legal outcomes of closed legal colorectal cancer cases compared

Patient characteristics

Presenting symptoms:
The average age of the patients involved in the legal cases was 55 years; notably, one third of them had not yet reached the age of 50.

Of the 159 patients only 10 were asymptomatic (6%). In four of these 10, a suspicious physical finding was identified during routine physical examination but was not pursued. Of the remaining six patients, all had identifiable personal or familial risks, but, in the opinion of experts, were inadequately investigated.

At the time of the initial presentation, 149 (94%) patients were symptomatic. The most frequent presentations in order of frequency were:

  • abdominal or anorectal pain
  • anorectal bleeding
  • change in bowel habit
  • anemia

Patient clinical outcome:
Analysis of expert opinions obtained in these College and legal cases suggests that multiple breakdowns in the evaluative process affected the patients' clinical outcomes. In some cases, this resulted in additional complex investigations and therapeutic procedures with associated morbidity and mortality.

Fifty-three patients had distant metastases when the diagnosis of colorectal cancer was ultimately made. At the time litigation initiated, 55 (37%) of the symptomatic patients had already died from their cancer (average age of 60 years), and family members brought the legal action.

Although the date of death is known for only 22 of these 55 symptomatic patients, the five-year mortality was 95 per cent in that group. The average interval between diagnosis and death was 1.5 years.

Presumptive diagnoses:
In this review of closed cases, the most frequent misdiagnosis was hemorrhoids, especially when the patient presented with symptoms of rectal bleeding. For those patients who presented with symptoms of abdominal pain the presumptive diagnoses included gastroenteritis, constipation or irritable bowel syndrome.

Identify the risks

Based on a review of the expert opinions obtained in these closed medico-legal cases the following risk management considerations have been identified:

  1. Have you considered the diagnosis of colorectal cancer in patients presenting with suggestive symptomatology regardless of their age?
  2. Should a digital rectal examination be performed?
  3. If the diagnosis of colorectal cancer is being considered, have the appropriate investigations been ordered, or a referral to an appropriate consultant made?
  4. Has there been adequate follow up of any investigative plan including a clear understanding of who will be the most responsible physician for the ongoing management of the patient?
  5. Is the follow up plan clear to the patient and both referring and consulting physicians?
  6. Have the history, including colorectal cancer risks, relevant physical findings, investigations, treatment plan and communications been documented in the clinical record?


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.