The short answer
A cancer screening result can be normal or abnormal. An abnormal result does not mean you have cancer; it means more testing is needed to find out. Screening tests can sometimes give false positives or false negatives. Follow-up tests, like a biopsy, are how doctors find out what an abnormal result really means.
An abnormal screening result does not mean you have cancer; it means more testing is needed.
A false positive is when a test looks abnormal but there is no cancer.
A false negative is when a test looks normal but cancer is actually present.
Follow-up tests, such as imaging or a biopsy, are used to find out what a result means.
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The full explanation.
The simple version
When you have a cancer screening test, the result is usually described as normal or abnormal. It is easy to hear "abnormal" and think the worst, but that is not what it means.
An abnormal result simply means something needs a closer look. It is a signal to do more testing, not a diagnosis. In fact, most abnormal screening results turn out not to be cancer.
An abnormal result is a reason to look closer, not a diagnosis.
Screening finds clues, not diagnoses
Screening tests are designed to sort people into two groups: those who almost certainly do not need more testing, and those who might. They are not meant to give a final answer.
For example, a screening mammogram might spot a shadow that needs another look. A stool test might detect blood that could have many causes. In each case, the screening has done its job by flagging something to check. The next tests decide what it really is.
Screening raises a hand and says "look here," and other tests answer the question.
False positives and false negatives
No test is perfect, and it helps to understand the two ways a screening result can be misleading.
- A false positive is when the test looks abnormal but there is no cancer. This is fairly common with screening. It can cause worry and lead to extra tests, which is one of the known trade-offs of screening.
- A false negative is when the test looks normal but cancer is actually there. This can happen when a cancer is small, hidden, or hard to detect.
Doctors expect that both can happen. That is exactly why an abnormal result leads to more testing rather than a diagnosis, and why new symptoms are worth reporting even after a normal screening.
Both false positives and false negatives are possible, so no single result is the final word.
What happens after an abnormal result
If a screening result is abnormal, your doctor will usually recommend follow-up steps to learn more. What comes next depends on the test and the finding, but common steps include:
- Repeating the screening test to confirm the finding
- Imaging tests, such as an ultrasound, CT scan, or MRI, to see the area more clearly
- A biopsy, where a small sample of tissue is removed and checked under a microscope
A biopsy is often the step that gives a definite answer, because looking at the actual cells is the clearest way to tell whether cancer is present.
Follow-up testing, sometimes ending in a biopsy, is how an abnormal result gets explained.
Common follow-up pathways
Different screening tests lead to different follow-up steps. If you are trying to make sense of a portal result, start with the guide that matches the wording you saw: abnormal mammogram, BI-RADS 0, positive FIT test, elevated PSA, or abnormal Pap or HPV-positive result.
Coping with the wait
Waiting for follow-up results can be stressful. It may help to keep a few things in mind.
Most abnormal screening results are not cancer. Having a clear plan for the next steps often makes the wait easier. And your care team is there to answer questions, so it is completely reasonable to ask what your result means, what the follow-up will involve, and when you can expect answers.
If a normal result comes back, that is reassuring, but stay aware of your body. If you notice new or lasting symptoms later, tell your doctor, even if your last screening was normal. Screening is a snapshot in time, and your own awareness fills in the rest.
Words to know
Tap any term to see what it means.
Common questions
Does an abnormal result mean I have cancer?
No. An abnormal screening result means something needs a closer look, not that cancer is present. Many abnormal results turn out to be harmless conditions. Follow-up tests are how doctors find out what is really going on.
What is a false positive?
A false positive is when a screening test suggests there may be cancer, but follow-up shows there is none. False positives are fairly common with screening. They can cause worry and lead to extra tests, which is one of the known downsides of screening.
What is a false negative?
A false negative is when a screening test looks normal but cancer is actually present. No test is perfect, so this can happen. It is one reason to report any new symptoms to your doctor, even if a recent screening was normal.
What happens after an abnormal result?
Your doctor will usually recommend follow-up tests to learn more. These might include repeating the screening, imaging tests, or a biopsy, where a small tissue sample is checked under a microscope. The follow-up plan depends on the type of screening and the finding.
Why do screening tests give wrong results sometimes?
No test is perfect. Some conditions can look like cancer on a screening test, and some cancers can hide or be too small to detect. Doctors know this, which is why an abnormal result leads to more testing rather than a diagnosis on its own.
Should I be worried while waiting for follow-up results?
Waiting is hard, but try to remember that most abnormal results are not cancer. It is fine to ask your care team what the result means, what the next steps are, and when to expect answers. Having a plan often eases the worry.
Questions to ask your doctor
Being prepared helps you get the most out of your appointments. Save or print these questions.
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Last updated: 2026-07-04Next planned review: 2027-01-04
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How this page was created
Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and checked line by line against the sources listed on it. That confirms the sources support what the page says. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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