Patient guide
Incidental findings after screening scans and tests: what they mean
The more you look, the more you find. Scans and broad blood panels commonly show unexpected abnormalities that are not related to any symptom. Most are harmless, but a few matter. This guide explains how incidental findings arise, how they are assessed and how to decide what to do.
Last checked: 2026-10-03
Key facts
At a glance.
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Common
A large proportion of whole-body or multi-region scans in healthy people show at least one incidental finding.
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Mostly harmless
Most are benign, such as cysts, small nodules or minor degenerative change.
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Need a plan
Responsible providers explain what follows if an incidental finding is reported, including who arranges and pays for follow-up.
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Anxiety is a harm
Uncertainty and repeated tests carry emotional and financial costs.
Why they happen
Imaging is sensitive and the body is variable. Cysts in the kidneys, liver and thyroid, small lung nodules, adrenal lumps and disc bulges are common in healthy people, increasing with age. Blood tests have reference ranges that cover most healthy people but, by design, leave some healthy people outside them. When many tests are done, the chance that at least one is abnormal rises quickly.
Typical examples
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Simple kidney or liver cysts, which are usually benign.
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Thyroid nodules, most of which are benign but some need ultrasound follow-up.
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Small lung nodules, which may need follow-up scans depending on size and risk.
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Adrenal incidentalomas, which are usually benign but may need hormone tests.
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Gallstones without symptoms.
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Slightly raised liver enzymes, cholesterol or blood sugar, which may reflect lifestyle or be transient.
How clinicians decide what to do
They consider the size, appearance and location of the finding, your age, symptoms and risk factors, and whether it is likely to change management. National and specialist guidance describes follow-up pathways for common incidental findings, such as thyroid nodules and lung nodules. Many require only reassurance or a single repeat scan after several months. A few need biopsy or surgery. The aim is to avoid missing important problems while not overtreating harmless ones.
Costs and consequences
Follow-up of incidental findings may involve further scans, specialist appointments and biopsies, with associated costs and small risks. Private providers may not cover these costs. Anxiety while waiting can be significant. Some people find that they carry a diagnosis label, such as a nodule, that affects insurance or peace of mind even when it is harmless. These are reasons to consider carefully before undertaking tests with a high chance of unexpected results.
Dealing with an abnormal result
Ask the clinician to explain what the finding is, how common it is, what the realistic range of causes is and what the plan is. Ask whether you need to do anything now, or whether monitoring is sufficient. Get a copy of the report and share it with your GP. Avoid searching alarming information online before speaking with a professional. If you are unsure of the plan, ask for a second opinion.
Before you have a test
Consider what you would do with the result, what unexpected findings might arise and whether you are comfortable with that. Ask the provider how they manage incidental findings, and who will follow them up. Tests for symptoms are different from screening, and the likelihood of useful findings is higher when symptoms or risk are present.
Keeping perspective
Many people find that an unexpected result dominates their thoughts for days or weeks. It can help to remember that most incidental findings turn out to be harmless, that clinicians have established pathways for the common ones and that asking for a clear plan, including dates, reduces uncertainty. If worry becomes overwhelming, tell your GP. Talking therapies and practical support are available, and you do not need to wait for a final answer before asking for help with anxiety.
Frequently asked
Questions people ask.
Quick, plain-English answers to the questions we hear most.
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Are incidental findings usually serious?
No. Most are benign, though a small number matter.
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Will the NHS follow up a private scan finding?
Often yes, if your GP agrees it needs assessment, though it may be re-assessed from scratch.
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Can I opt out of incidental findings?
Some providers allow you to limit what is reported, but this is complex. Ask before testing.
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What is an incidentaloma?
A mass found unexpectedly on imaging done for another reason, commonly in the adrenal gland, thyroid or pituitary.
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Should I worry about a small lung nodule?
Most are benign. Clinicians follow guidance on size and risk to decide on follow-up.
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Do blood test abnormalities need action?
Mildly abnormal results are often repeated before action, since many are transient.
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Can stress affect results?
Illness, exercise, diet and medicines can all affect blood tests.
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Who pays for follow-up?
It depends. Ask providers beforehand whether follow-up is included.
Where this comes from
Sources and checking.
This guide is for information, not medical advice.
Your GP or consultant knows your history and can tell you which parts apply to you. If your symptoms are severe, rapidly worsening, or come with red-flag features, seek urgent medical care. Figures and availability change, so treat them as a guide and confirm with the provider.
Published 2026-10-03, next review 2027-10-03.
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UK National Screening Committee, recommendations and screening programme information (gov.uk/uk-nsc)
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General Medical Council, Good practice in prescribing and managing medicines and devices (gmc-uk.org)
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NHS website, NHS Health Check pages (nhs.uk)
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NICE guideline NG12, Suspected cancer: recognition and referral (nice.org.uk)