How is Cancer Misdiagnosed?

The journal BMJ Quality and Safety estimates that cancer misdiagnosis may occur at rates of up to 28 percent. Despite this shocking statistic, survey data indicates that doctors are significantly underestimating the occurrence of cancer misdiagnosis. In order to understand cancer misdiagnosis and how it occurs, it is important to understand the process of cancer diagnosis. When approaching cancer diagnosis, doctors and patients should understand that there is no single test that can provide a 100-percent accurate cancer diagnosis.

Cancer misdiagnosis may occur at any stage during the cancer misdiagnosis process. Cancer misdiagnosis may occur due to human error such as doctor negligence or incompetence when determining which types of cancer testing may be needed. Cancer misdiagnosis may begin during the testing process, such as errors in performing diagnostic imaging or improper procedure when collecting cell samples for a biopsy. In some cases, cancer misdiagnosis occurs despite all proper efforts from doctors, specialists, and patients.

Cancer Misdiagnosis in Testing

Cancer misdiagnosis often occurs due to imperfections or human error in the testing process. Cancer misdiagnosis from the testing process occurs as false positive and false negative test results. False positive cancer test results indicate that a cancer is present, although the patient does not truly have cancer. Adversely, false negative test results indicate that a cancer patient does not have cancer. In any event, faulty cancer screening results can have devastating results for the patient.

How Cancer Testing Works

Different types of cancer testing function in different ways, which can play a role in how a patient’s cancer is diagnosed. Virtually all types of cancer testing must be analyzed and interpreted by pathologists. Pathologists are trained specialists who study and diagnose diseases such as cancer. Despite correct results from cancer testing, human error or a general lack of cancer knowledge may lead to cancer misdiagnosis.

Cancer Diagnosis Is Subjective

Cancer misdiagnosis often occurs due to differing expertise, knowledge, and opinions of pathologists when examining cell samples or diagnostic imaging results. When reviewing the same sample, two different pathologists may come to two opposite conclusions on whether or not the sample exhibits signs and patterns of cancer. This is often the case when a patient is diagnosed with a non-cancerous condition, but later analysis from a different pathologist reveals that the patient’s abnormal cells are cancerous.

For this reason, patients should seek a second opinion from oncologists or facilities that specialize in the type of cancer in question. A medical facility that offers general diagnostic services may not be able to offer the level of expertise required for the diagnosis of a specific type of cancer that has a unique presentation. In many cases, pathologist experience is the difference between cancer misdiagnosis and a correct and timely diagnosis.

Common Cancer Testing Failures

Certain types of cancer testing may be more likely than others to lead to a cancer misdiagnosis. Mammography, a form of X-ray for breast cancer diagnosis, may have a cancer misdiagnosis rate of up to 20 percent. Other types of cancer testing such as tumor markers in the blood may be effective in some cases, but ineffective in others. The generally misunderstood nature of cancer often creates difficulty in properly classifying and identifying cancer.

Breast Cancer Mammography

Mammograms are one of the most common cancer screening methods that lead to a false breast cancer diagnosis. A study published in the Journal of the National Cancer Institute indicates that several factors may increase the risk of faulty mammography results. Among the most common risk factors is high breast tissue density. Increased breast density may obscure the ability of the mammography to identify potentially cancerous lesions. Breast density is primarily genetic. However, younger women may be more likely to receive a mammographic cancer misdiagnosis due to higher breast density than older women.

Blood Test Tumor Markers

Certain types of blood testing for cancer are designed to identify tumor markers. Tumor markers are certain chemicals that may be produced by cancerous tumors. However, certain tumor markers are produced naturally in the body. Elevated levels of tumor markers may indicate cancer, but may also indicate other non-cancerous conditions. This phenomenon can lead to cancer misdiagnosis. Additionally, tumor markers may not always be present in cancer patients. When tumor markers are identified, they may not be specific to a single type of tumor, which may present difficulty during cancer diagnosis.




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