So you have a lung nodule.
Someone has told you there is a small spot on your lung, and you are probably looking for plain information. This page explains what a lung nodule is, what usually happens next, and what to ask your doctor. It is general education, not advice about your own scan.
What a lung nodule is.
A lung nodule is a small, roughly round spot in the lung that shows up on an imaging scan. Most are a few millimeters across — smaller than a pea. They are common, and they are found in people of every age and background.
Nodules can be scar tissue from an old infection, a small patch of inflammation, a cluster of blood vessels, or a number of other harmless things. Some are cancer. The great majority are not.
Why it was found.
Most lung nodules are found by accident. Someone has a CT scan for an entirely different reason — chest pain, an injury, shortness of breath, a check before surgery — and the scan happens to include the lungs. The nodule was not what anyone was looking for. Doctors call this an incidental finding.
Most nodules are not cancer.
That is the first thing to hold onto. The large majority of small lung nodules turn out to be benign, meaning not cancer. Your doctor will weigh several things when thinking about yours: how big it is, what shape and texture it has, whether you have smoked, your age, and whether it changes over time.
At the same time, finding a lung cancer early matters a great deal. Lung cancer caught at its earliest stage is treated very differently, and far more successfully, than lung cancer found later. That is why a nodule is taken seriously even when it is likely to be harmless.
What usually happens next.
For most people, the answer is another scan later on — in three months, six months, or a year, depending on the nodule and on your own risk. This is called surveillance. If the nodule stays exactly the same over time, that is reassuring. If it grows, that changes the picture.
Waiting is uncomfortable, and it is reasonable to find it so. It is done because, for a small nodule, time has traditionally been one of the few reliable ways to learn more. Sometimes a doctor will recommend something faster instead, such as a PET scan or a biopsy, where the nodule or your own risk factors warrant it.
Why small nodules are the hard ones.
It is natural to assume a smaller nodule is an easier problem. In one sense it is — smaller nodules are less likely to be cancer. But they are also harder to judge, because there is less to look at. A very small nodule may be smaller than the eye can assess, even for an experienced radiologist looking carefully.
This is why guidelines often recommend waiting for small nodules. It is not that the nodule has been judged harmless. It is that, at that size, there has historically been little to go on other than watching whether it changes.
Where AI analysis fits in.
Software now exists that can analyze the image of a nodule in ways the human eye cannot. These tools measure patterns in the CT image itself — texture and structure at a level too fine to see — and compare them against large databases of nodules whose outcomes are already known. The result is a score — RevealDx calls it the Malignancy Similarity Index, or mSI™ — that tells the radiologist how closely your nodule resembles nodules that turned out to be cancer, and how closely it resembles those that did not.
RevealAI-Lung, made by RevealDx, is one of these tools. It is cleared by the FDA for use on incidentally found lung nodules between 6 and 15 mm in adults. A few important things about how it works:
- It is used by your radiologist, not by you. It is a prescription medical device.
- It produces a score, not a diagnosis. Your doctors interpret it alongside everything else they know about you.
- It works on the scan you have already had. It does not require another scan or another visit.
- It does not replace follow-up, and it does not make the decision. It is one more piece of information.
Not every hospital or imaging center uses tools like this, and availability varies. Your care team can tell you what is available where you are being treated.
Questions worth asking your doctor.
You are entitled to understand what is happening and why. These are reasonable things to ask.
- How big is my nodule, and where is it?
- What do you think is the most likely explanation for it?
- What is the plan, and what is the reasoning behind that timing?
- What would change the plan?
- Are there ways to learn more about this nodule without waiting?
- Is any additional analysis of my scan available here?
- Who do I contact if I do not hear anything, and when should I expect to?
That last one matters more than people expect. Nodule follow-up is sometimes missed simply because a scan was never scheduled or a result never reached the right person. Knowing who to call, and when, is worth writing down.
We cannot advise you about your own scan.
RevealDx makes software used by radiologists. We are not able to review anyone’s images, answer questions about an individual result, or give medical advice. The people who can are the ones treating you — your doctor, your radiologist, and the nurse or navigator coordinating your follow-up.
This page is general information about lung nodules. It is not a diagnosis, a recommendation, or a substitute for the judgement of your own clinicians.