One of the most common tests for detecting cancer is magnetic resonance imaging (MRI). Like other cancer tests, this type of scan has a few pros and cons, with the biggest advantage being how effective it is. This is especially true for patients with dense tissue, because other common cancer tests usually require the tissue to be thin for the most accurate results. On the other hand, MRI for cancer detection is known for getting more false-positive results than other types of screenings, often leading to follow-up tests that are expensive and not always necessary. Additionally, some patients are hesitant to undergo an MRI, because entering the MRI machine has been known to trigger claustrophobia.
Many doctors recommend the use of MRI for cancer detection because it is among the most effective screenings. Part of the reason for this is that the MRI can detect cancer even in dense tissue, which is a challenge for some other cancer tests. For example, an MRI is often preferred over a mammogram in breast cancer detection because it can locate abnormal cells even in young women's breasts, which tend to be quite dense. Mammograms are more likely to miss a tumor unless the tissue is thin and, thus, able to be flattened easily. Therefore, doctors are likely to recommend an MRI for cancer detection in young patients with particularly dense tissue.
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The downside of the efficacy of the MRI is that it can cause false-positive results. Aside from the stress this can cause patients, it also can lead to follow-up tests, such as biopsies, to get a closer look at the tissue before making a cancer diagnosis. This can be expensive for patients, because insurance does not always cover these tests. In fact, some U.S. insurance companies do not cover an MRI to begin with, unless the doctor can offer evidence that it is medically necessary. This usually only works if the patient has symptoms or a history of cancer, so an MRI as part of a regular checkup often must be paid for by the patient.
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Even when an MRI for cancer detection is paid for by insurance and recommended by a doctor, some patients are hesitant to undergo this screening. This is often a result of claustrophobia, because the test requires patients to enter a machine that is barely larger than their body. This may cause anxiety, so some patients skip having an MRI for cancer detection in favor of other screening methods.