Medical malpractice can result in devastating outcomes for individuals and their loved ones. Negligence could result in pain and suffering, or even permanent injuries or death. It often has far-reaching implications for the victim and their family.

In the recent case before the Ontario Superior Court of Justice of The Estate of Mary Fleury v Kassim, the plaintiffs successfully argued that a pathologist’s failure to identify cancer was negligent. The case provides an example of what it takes to prevail in a medical negligence action.

Deceased was diagnosed with appendiceal cancer years after having her appendix examined

In 2011, the deceased developed appendicitis and had her appendix removed. Samples of the appendix were examined by the defendant pathologist. The defendant did not identify cancer.

In 2015, the deceased began suffering from bloating and pain on the right side of her abdomen. Doctors suspected a small bowel obstruction, so they performed a laparoscopy and made an identification suggestive of metastatic disease.

Subsequent pathology confirmed that the deceased had a tumour where the appendix should have been. The defendant re-examined the 2011 appendiceal slides and observed that the samples contained cancer.

The deceased passed away in 2016, at the age of 45.

Plaintiffs commence proceedings for negligent misdiagnosis

The deceased’s estate and family members commenced proceedings, arguing that the defendant was negligent when he failed to diagnose the deceased’s appendiceal cancer when she had her appendix removed in 2011. They alleged that she would still be alive if she had been properly diagnosed.

The pathologist agreed that he made a mistake when he failed to identify the cancer in 2011. However, he argued that he was not negligent and that she would have regrettably died even if he had made the diagnosis in 2011.

Elements to be established in a medical negligence case

In order to succeed in a negligence case, the plaintiff needs to prove, on a balance of probabilities that:

  • The defendant owed a duty of care to the deceased;
  • The defendant breached the standard of care;
  • The plaintiff sustained damage; and
  • The damage was caused, in fact and in law, by the defendant’s breach.

It is well-established that doctors owe a duty of care to their patients. This includes situations where a specialist reviews the patient’s tissue samples, even if the patient and doctor never actually meet.

So, the two issues for determination in this case were whether the pathologist breached the standard of care and, if so, whether the breach caused or contributed to the death of the patient.

Standard of care expected of medical practitioners

The standard of care required of a medical practitioner is to exercise a reasonable degree of skill and knowledge and the degree of care that could reasonably be expected of a normal, prudent practitioner of the same experience and standing.

However, if the medical practitioner holds themself out as a specialist, a higher degree of skill is required because of their special training and ability. To be considered reasonable, this standard is not one of excellence that amounts to perfection. A physician’s honest and intelligent exercise of judgement will satisfy the standard of care.

When determining whether a doctor has breached the standard of care, the court needs to determine what was reasonably required to be done. For this, expert evidence is often needed to help the court.

Court finds that the defendant breached the standard of care

The court considered whether the cancer in the appendix samples should have been seen through the use of standard pathologic practice by a “reasonably prudent” pathologist.

After considering the expert evidence, the court found that the standard of care expected of a pathologist included carefully reviewing the sample to determine the presence of any abnormalities, such as evidence of cancer.

The plaintiff’s expert opined that the cancer in the deceased’s sample was obvious at a low level of magnification. Furthermore, the defendant identified the cancer with “moderate ease” upon re-examination in 2015. Accordingly, the court held that the defendant did not meet this standard of care.

Causation in the context of delayed medical diagnosis

The plaintiff also needs to prove that, if not for the defendant’s negligent act, the injury would not have occurred.

In the context of a delayed medical diagnosis, a plaintiff must prove on a balance of probabilities that the delay caused or contributed to the unfavourable outcome. In other words, if the unfavourable outcome would not have been avoided even with prompt diagnosis and treatment, the claim must fail.

As with the standard of care, expert evidence is often needed to help the court decide the effect of a delay in diagnosis.

Court finds that the deceased would likely have sought cancer treatment and would be alive today

The court considered the expert evidence provided by both parties. The plaintiff’s expert opined that the deceased was at Stage III cancer in 2011 rather than Stage IV. The expert believed that, if the deceased had received treatment for the appendiceal cancer, she would have been cured with a five-year risk of recurrence of less than 30 percent.

As a result, the court was satisfied that if not for the defendant’s failure to meet the standard of care, the deceased would likely have sought out treatment for cancer and would be alive today.

The plaintiffs therefore succeeded in their claim and were entitled to damages.

Contact Tierney Stauffer LLP for Advice on Medical Malpractice Claims

At Tierney Stauffer LLP, we know how overwhelmed you may feel about the prospect of launching a medical or hospital malpractice lawsuit. If you have a valid claim against a medical practitioner or hospital, you need a strong advocate by your side to fight their insurers and lawyers. It is important that you seek prompt advice from our personal injury lawyers, who have a great deal of experience working with clients on medical malpractice claims throughout Ontario. Call us at 1-888-799-8057 or reach out online to set up a consultation today.


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