The short answer
A "pulmonary nodule" is a small, rounded spot in the lung seen on a scan. It is not a diagnosis and can have more than one cause. Your doctor weighs how it looks and your risk factors to decide whether to repeat a scan later or look further. Ask what the plan is for you.
A pulmonary nodule is a small spot in the lung seen on a scan.
Doctors use how the nodule looks and your risk factors to plan follow-up.
Follow-up may include a later scan or more tests. Ask what is planned for you.
A nodule is not a diagnosis — it's something to monitor or investigate.
On this page
Choose how you want to read this
The whole article, with every detail and caution.
What a pulmonary nodule is
A pulmonary nodule is a small, round spot in the lung. It is seen on imaging such as a CT scan. A nodule is a description of what the scan shows. It is not a diagnosis, and it can have more than one cause.
How follow-up is decided
Your doctor decides whether a nodule needs to be watched, rechecked or tested further. The plan depends on how the nodule looks and on your own risk factors, such as smoking history. We could not confirm specific size cutoffs or scan schedules from a federal source, so this page does not list them. Ask your team what schedule they recommend for you, and why.
Why follow-up scans matter
NCI notes that when a previous scan is available, a nodule's growth rate can be assessed. Keep your follow-up appointments, and bring or send any older scans from other facilities so they can be compared.
If you have new or worsening symptoms, such as a cough that will not go away, coughing up blood, chest pain or trouble breathing, call your care team right away. Do not wait for the next scan. Call 911 for severe trouble breathing or heavy bleeding.
What to ask your team
- How large is my nodule, and what follow-up schedule do you recommend?
- What specifically about my history or the nodule's appearance affects my personal risk level?
- What happens if the follow-up scan shows growth?
- Is a PET scan or biopsy recommended now, or only if the nodule changes?
Sources
Common questions
Should I be worried about a lung nodule?
A nodule alone is not a diagnosis. It needs follow-up that your doctor will plan. Your risk factors, like smoking history, affect the plan. Ask your team what they think it could be.
Why might my doctor suggest a repeat scan instead of a biopsy now?
That is a decision for your doctor, based on your nodule and risk factors. Ask why they chose that approach for you.
Questions to ask your doctor
Being prepared helps you get the most out of your appointments. Save or print these questions.
Tap a question to save it to your list (kept on this device).
More words from this kind of report
Other guides in scan & imaging reports.
Your next step
Plain-language definitions for the words on your report.
Talk with a trained specialist or navigator
Cancer Explained provides educational guidance, but does not replace trained specialists, social workers, or your medical team.
Talk to a trained cancer information specialist
Free, confidential assistance from NCI Cancer Information Service via phone, chat, or email.
Contact your oncology team
Locate after-hours contact numbers, portal messages, or urgent triage phone lines.
Find a patient navigator
Get one-on-one help with appointments, logistics, translation, and care coordination.
Find a genetic counselor
Discuss inherited mutation risk, family history, and genetic testing options.
Find an oncology social worker
Access emotional counseling, family support groups, and mental health resources.
Find a financial navigator
Locate copay assistance foundations, grant programs, and lodging/travel support.
Find a clinical-trial specialist
Search matching studies and speak with NCI trial information specialists.
Get urgent help
Fever of 100.4°F (38°C) or higher during chemo, severe pain, or trouble breathing: call your cancer care team right away, day or night. Call 911 for an emergency.
Plain-language explanation of the published sources cited on this page. AI-assisted, source-checked, not clinician-reviewed.
Last updated: 2026-10-16Next planned review: 2027-07-12
Review details and limits
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, and this 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 then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.
General education — varies by person. Answers genuinely differ between people. This page explains what commonly varies and points you to your care team 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.
Words to know
Tap any term to see what it means.
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, and this 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 then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. 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.
Read more about our editorial process, our use of AI, and our corrections policy.
Spotted a problem? Report an error — a factual mistake, broken or outdated source, confusing wording, or anything that seems unsafe. Please do not include names, medical record numbers, dates of birth, addresses, or other identifying medical information in your report.
After using this page, do you understand what to do next?
Anonymous — we only record the answer, never who gave it.