Causation Challenges in Cancer Cases

To be successful, a claim in medical malpractice requires the plaintiff to prove a breach of the standard of care, causation and damages.

In the seminal case of Snell v Farrell, the Supreme Court of Canada explained causation as “an expression of the relationship that must be found to exist between the tortious act of the wrongdoer and the injury to the victim in order to justify compensation of the latter out of the pocket of the former” (para. 27). Essentially, causation is a link between the negligent conduct, and the resulting injury. The plaintiff must prove on a balance of probabilities (at least 51% likelihood) that the negligent conduct is what caused the injury. The negligent conduct need not have been the sole cause of the injury. Rather, the test for causation is the “but for” test: the plaintiff must prove that “but for” the negligent actions (or omissions) of the defendant(s) (in the case of medical negligence, a health care professional), the injuries and/or outcome would have been materially different.

In most cases involving negligence in the diagnosis of cancer, causation is the biggest hurdle for the plaintiff. This is because even though the negligence may have caused a delayed diagnosis in the plaintiff’s cancer, such negligence cannot be said to have caused the cancer, and thus the cause of related surgeries and/or chemo- radiation therapies, which the plaintiff may have been required to undergo in any event. In these instances, while there may be damage and injury resulting from the delayed diagnosis, and even where is a clear breach in the standard of care, it can be challenging to prove there would have been a materially different outcome absent the negligent care. This difficulty also arises in the context of diagnoses of rare forms of cancer, and/or cancers for which there is currently no cure, or that are resistant to treatment. In those instances, even with proper care or timely diagnosis, the plaintiff cannot prove the outcome would have been materially different due to the nature of the illness, and the absence of effective treatment.

Notwithstanding these challenges, delayed diagnosis of cancer cases can be viable and successful for the plaintiff where the delay is sufficiently lengthy such that certain treatments and their effectiveness – such as the invasiveness and ultimate success of surgical excision, chemo and radiation therapy – would have been materially different, and recurrence and ultimate survival rates materially improved by an earlier diagnosis.

If you or a family member have experienced a delayed diagnosis in cancer, it is important to consult with a knowledgeable medical malpractice lawyer who can assess the viability of a successful claim, and work to obtain compensation for damages suffered as a result of another’s negligent care. Wagners has extensive experience in medical negligence and can assist you in screening and pursuing a claim.

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