Imagine for a moment that your doctor has told you to get a routine chest X-ray or CT scan because you are having chest pain…are about to have shoulder surgery…or may have cracked a rib.

Then your doctor calls to say that the test unexpectedly detected a “spot” on your lung. Your first thought is, It might be lung cancer!…but take a deep breath.

Here are the steps you need to take to preserve your health and your sanity…

STEP 1: Don’t panic. Most lung spots (dense areas within the lung that appear as white, shadowy
areas on imaging tests) are not cancer. In fact, when doctors screen high-risk patients (people over age 55 who have smoked roughly 30 “pack years”—a pack year is defined as smoking one pack of cigarettes a day for a year) specifically for lung cancer, only about 1% to 2% of nodules that are detected on CT scans are cancerous.

When the spot is found incidentally—that is, during an imaging test that wasn’t given because cancer was suspected—the risk is even lower.

Many conditions that don’t have anything to do with cancer can cause a spot on the lung. These
include… 

Infection from tuberculosis, pneumonia, bronchitis or other illness involving the lungs.

Inflammation from an autoimmune disease—rheumatoid arthritis, for example, is a common cause of inflammatory lung nodules.

Scarring from pulmonary fibrosis or other lung disease.

Environmental irritants, such as  asbestos, coal dust or silicone.

Environmental infection, such as histoplasmosis, caused by fungus spores in bird or bat droppings. People can be exposed while demolishing old buildings, for example, or by spending time in bat-filled caves.

STEP 2: Talk about your history. If you’ve been told that you have a spot on your lung, make an appointment with the doctor who knows you best to review your medical history…take stock of your lung cancer risk…and decide your next steps.

First, your doctor, often in consultation with a radiologist, will want to compare the latest chest X-ray or CT scan with any previous imaging tests of your chest. It is possible that the spot has been there for years but wasn’t previously identified. If the spot was present and hasn’t grown for many years, the chance that it is malignant is low.

Next, discuss your recent health and personal risk factors for lung cancer with your doctor. Have you had a cough, the flu or a severe cold? Do you have an autoimmune disease? Have you had any risky environmental exposures? These all have the potential to cause lung spots.

If you have a history of another malignancy somewhere in your body, your doctor will want to rule out a metastasis to the lungs.

Of course, smoking history is very significant. Smokers have a higher risk for lung cancer…former smokers have a lower risk than active smokers…and nonsmokers have the lowest risk. For everyone, however, the risk for lung cancer increases with age.

Important: For reasons no one understands, the incidence of lung cancer is rising among never-smokers, especially women. Therefore, people who have never smoked should not assume that they can’t have lung cancer. Any lung spot should be evaluated by an expert even if you don’t have serious risk factors for lung cancer.

STEP 3: Get follow-up testing. If your nodule was found incidentally, you’ll need focused follow-up imaging. For most people, the best option is a low-dose CT (LDCT) scan without IV contrast. This test gives a clear view of the nodule with minimal radiation.

The dose of radiation used in an LDCT is about the same as that used in a standard mammogram. The LDCT will let doctors see the size and qualities of the nodule.

For example…*

Small nodules—spots that are less than one-fifth of an inch (5 mm) are very low risk but should be followed with surveillance in most cases. For example, such nodules should usually be monitored for two years at set time intervals to reveal if there is any growth in the nodule. A stable nodule without growth for two years is safely considered benign.

Larger nodules—spots that are about one-third of an inch (8 mm) or greater demand a thorough workup. This may include a positron emission tomography (PET) scan, which involves an injection of radioactive tracers that light up to indicate areas that may be cancerous and would require a biopsy for confirmation, or a needle or surgical biopsy if the person’s risk factors are high and the radiographic appearance warrants a tissue diagnosis.

Spiky nodules—or those with an irregular surface—are generally more concerning than smooth
nodules.

Solid and part-solid nodules—meaning they have a solid density measurement throughout the entire spot or some solid component—are typically more concerning than nonsolid nodules.

More is usually better. If your doctor says that you have multiple nodules (that is, more than one), the nodules are less likely to be cancer.

Because surveillance is the most practical way to determine whether a spot is dangerous, it’s important to get expert recommendations. That’s why decisions regarding surveillance are usually made by a multidisciplinary team that includes pulmonary doctors, thoracic surgeons and radiologists.

Even if a nodule is deemed benign, depending on your personal medical history, your doctor may recommend a yearly follow-up scan.

For example, if a person has a close relative with cancer (a first-degree relative such as a parent or sibling) or a history of heavy smoking, he/she will likely need an annual screening to check for new nodules that may develop and possibly become cancerous.

Important: You should not settle for an X-ray as a follow-up. An LDCT provides greater detail.

Among current or former heavy smokers, LDCT has been shown to reduce the risk for lung cancer deaths due to early detection. In the National Lung Screening Trial, more than 53,000 men and women (ages 55 to 74) who were current or former heavy smokers were randomly assigned to receive annual screenings with either LDCT or standard chest X-ray for three consecutive years. The LDCT group had 20% fewer lung cancer deaths than the X-ray group.

STEP 4: Get a closer look. If follow-up scans show that a nodule is getting larger and/or changing in appearance, your physician will need to take a biopsy to determine whether it’s malignant.

If the nodule is easy to reach—for example, in the airway—a biopsy may be done with a very thin lighted instrument that is threaded through the mouth or nose and down the throat to snip off a piece of the nodule.

A needle biopsy may be preferred if the nodule is in the peripheral lung or near the chest wall.

A surgical biopsy that involves making an incision to remove a tissue sample may be needed if the approaches described above fail to make an adequate diagnosis or if the likelihood of cancer is considered high.

If lung cancer is diagnosed, then it is crucial to make a prompt appointment with a thoracic surgeon and/or oncologist to begin treatment.

*The sizes and characteristics of nodules that require follow-up (as well as the schedule for such testing) may vary depending on the medical facility where you are receiving care. Many medical centers use the Fleischner Guidelines for Pulmonary Nodules, FleischnerSociety.org.