Signs that Cancer is Misdiagnosed

Cancer misdiagnosis is more common than many may assume. When approaching a potential cancer misdiagnosis, it is important for doctors and patients to be aware of potential signs that cancer is misdiagnosed. While cancer misdiagnosis does not always display the same warning signs, certain factors may be identified to decrease the risk. First and foremost, any potential symptoms or signs of cancer should be thoroughly investigated by the treating physician. Basing a cancer diagnosis on the results of one test can be problematic and thus increase the risk of a cancer misdiagnosis.

Cancer Diagnosis Methods

Cancer misdiagnosis often occurs due to the doctor’s failure to identify symptoms, or fails to investigate certain symptoms with appropriate testing. In many cases, cancer symptoms may be difficult to identify, as they often do not have a specific presentation or pattern. However, it is the doctor’s medical duty to provide the patient with a thorough explanation of all symptoms in order to provide a proper diagnosis and treatment plan. Certain cancer diagnosis testing options are deemed medically appropriate in certain circumstances, and should be administered under these circumstances unless medically contraindicated.

The most common methods for diagnosing cancer include:

  • Diagnostic imaging, such as X-rays, magnetic resonance imaging (MRI), computerized tomography (CT), positron emission tomography (PET), and ultrasound.
  • Laboratory testing of bodily fluids or tissues, such as blood, urine, or tissue samples of a suspicious growth. Biopsies are a common laboratory test during which a sample of tissue is collected for observation from a specialized pathology laboratory.
  • Endoscopic testing, during which a flexible tube with an attached camera is inserted into the patient through an orifice. Gastrointestinal endoscopy typically takes place through the mouth and down through the esophagus. Colorectal endoscopy, or colonoscopy, typically takes place through the patient’s rectum.
  • Genetic testing, which typically involves several blood samples that are collected and analyzed in a specialized laboratory. Genetic testing is typically used to identify certain genes which increase the risk of developing cancer. Genetic testing does not provide patients or doctors with a definite cancer diagnosis, and should therefore not be treated as such.

Signs of Cancer Misdiagnosis

Patients should be aware of their current state and cancer diagnosis throughout all stages of the cancer diagnosis process. For example, patients are encouraged to seek a second opinion and question the decisions of their doctor when a suspicious growth is identified, but not examined more closely using diagnostic image testing or a biopsy. Patients are also recommended to seek a second opinion when a non-cancer diagnosis is made based on symptoms that do not adequately match the diagnosis. This may occur in a patient who is diagnosed with colon cancer, but whose symptoms become worse under stress. The worsening of symptoms is a unique characteristic of inflammatory bowel diseases (IBDs) such as irritable bowel syndrome (IBS), and typically not a characteristic of colon cancer.

Other signs of cancer misdiagnosis may include scenarios when:

  • A patient’s treatment for a diagnosed condition does not improve the patient’s symptoms
  • A treatment plan is not medically or logically congruent to the patient’s symptoms
  • The doctor makes a confirmed diagnosis or administers treatment based on a single test’s results
  • The doctor ignores or disregards certain symptoms within the patient
  • The doctor fails to provide adequate testing based on certain symptoms, such as a colonoscopy for certain colorectal symptoms
  • The doctor is unable to or purposely fails to answer a patient’s questions regarding his or her condition
  • The patient witnesses evidence suggesting a lack of communication between employees in a medical facility, or between employees of different medical facilities

Premature Cancer Diagnosis

A premature cancer diagnosis can occur when the treating physician bases a cancer diagnosis on a single test, or a test that may not be as specialized as others. It is generally well-known that certain tests pose a higher risk of providing false negatives or false positives. False negative test results indicate that a cancer patient does not have cancer. False positives indicate cancer in a patient who does not have cancer. When a suspicious growth or lesion shows negative test results, it is generally recommended to retest the area to be certain. Likewise, when a test indicates that cancer is present, the area in question should be retested.

Faulty Cancer Screening

Certain cancer diagnosis methods may be more likely to provide faulty results than others. For example, data indicates that mammography for breast cancer may have up to a 20 percent failure rate. The density of the patient’s breast tissue plays a large role in mammography misdiagnosis, as dense breast tissue may obscure test results and prevent the mammography from identifying abnormal growths. Other types of diagnostic imaging may fail to indicate cancer when the cancerous growth is microscopic or very small.




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