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"Can a DNA test tell me if I have cancer?"

ZocdocAnswersCan a DNA test tell me if I have cancer?


Hello, doctor. I wish to know whether a DNA test can tell me if I have cancer. Thank you.


As DNA (genetic) testing becomes more popular and medical scientists’ understanding of cancer rapidly evolves, it is reasonable to ask whether a test of DNA might be able to give doctors and patients a diagnostic tool in the fight against cancer. My answer to this test is applicable to our current scientific knowledge, and in the future the answer to this question may change dramatically. Currently there are a number of DNA tests which can help better predict the chances of developing cancer, but none are commercially available to diagnosis active cancer. Some of the most common genetic (DNA) tests for adults regarding cancer include tests for two genes known as BRCA1 and BRCA2. These are genes that normally suppress the development of tumors, but when they are abnormal can lead to increased risk of breast and ovarian cancer. There are, however, a host of tests for other less common conditions that predispose to cancer. These include the following cancers: parathyroid, thyroid, pancreatic, colon, and gastric (stomach) among others. Right now these tests are typically only done to screen individuals who have a strong family history of certain types of cancers and are not used to screen the general public. So though scientists are currently working to develop blood tests that detect fragments of DNA from tumors in the blood, none are currently on the market. But stay tuned, this may be changing in the near future. If you have more questions or concerns you should talk with your primary care physician who can help you navigate this issue. Good luck!

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