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"Can a doctor detect cancer with a blood test?"

ZocdocAnswersCan a doctor detect cancer with a blood test?


Many people in my family have had cancer and I'm only 27 but I have had a lot of different health issues. I'm worried maybe they might be from some cancer I don't know about. Can I be blood tested for cancer? How do doctors find cancer if you don't have a tumor?


There are many kinds of cancer, and there are many kinds of tests to determine if you have cancer. Most tests are not valuable to be performed on the general population, but if you have a strong family history of cancer, as you suggest, it would be worth discussing the problem with your doctor to determine if any of the types of cancer seem related to each other and if there may be a genetic basis for them that you should be concerned about or tested for. Regardless of what he or she may tell you, eating well, maintaining a healthy weight, drinking in moderation, and not smoking will help to decrease your risks of cancer. Timely and appropriate cancer screening, such as mammograms and colonoscopies are also important. For the other types of cancers, the testing and screening has not quite reached a level where routine testing in the absence of other symptoms is recommended. Depending on the symptoms that you are indicating you have, you doctor may feel that ordering certain tests would be valuable to decrease your level of anxiety about any of these more rare cancers. Please speak to your doctor about your symptoms and your concerns.

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