Emphysema found by chance on CT: what comes next

The main guidance

NICE NG115 (UK, 2018): consider a primary care respiratory review and spirometry for people with emphysema or signs of chronic airways disease on a chest X-ray or CT. (NICE NG115)
GOLD 2026 report: emphysema and other airway changes on CT should raise suspicion of COPD and lead to a detailed check of symptoms and consideration of lung function testing if not done before. (GOLD 2026)
Fleischner Society (2015): a standard way for radiologists to describe the type and extent of emphysema on CT. (Fleischner 2015)

Who it applies to

Adults whose CT or chest X-ray, done for another reason, mentions emphysema. (NICE NG115) It is common on lung cancer screening scans: the USPSTF lists it among the common incidental findings, and a UK screening study found it in 33.4% of people at their first scan. (USPSTF 2021)(SUMMIT 2023) If you already have a COPD diagnosis, see screenings if you have COPD.

How it is described on a CT report

Fleischner Society visual types of emphysema on CT (simplified)
Type	Grades used	Notes from the statement
Centrilobular	Trace, mild, moderate, confluent, advanced destructive	Mild means scattered spots separated by large areas of normal lung; in confluent and advanced destructive emphysema the spots merge and lung structure is lost
Panlobular	No subgrades listed	Affects all of each lung unit evenly; linked with alpha-1 antitrypsin deficiency but also seen without it
Paraseptal	Mild or substantial	Lies just under the lung lining, along the chest wall and lung edges

Types and grades are as given in the Fleischner Society statement, which also describes airway wall thickening and other airway changes that may appear in the same report. (Fleischner 2015) Some reports and studies instead give the share of lung affected; the UK SUMMIT study used mild (over 5 to 25%), moderate, severe and very severe. (SUMMIT 2023)

Why emphysema on CT is not the same as COPD

GOLD says spirometry showing airflow obstruction (a post-bronchodilator FEV1/FVC below 0.7) is needed to make a COPD diagnosis. (GOLD 2026)
The Fleischner Society notes that emphysema and airway changes are found in a substantial share of people who do not meet the breathing test criteria for COPD. (Fleischner 2015) In the SUMMIT study, 32.3% of people with emphysema on CT did not have airflow obstruction, and 47.7% had no earlier COPD diagnosis. (SUMMIT 2023)
GOLD uses the term pre-COPD for people with lung changes such as emphysema or symptoms but no airflow obstruction, and says not all of them go on to develop COPD. (GOLD 2026)

What usually comes next

A review and a breathing test: NICE says to consider a respiratory review and spirometry. (NICE NG115) For what the test involves and its results, see spirometry for COPD.
If spirometry is normal and there are no symptoms, in people who do not smoke: NICE suggests asking about a personal or family history of lung or liver disease and considering other causes such as alpha-1 antitrypsin deficiency, says the emphysema is unlikely to get worse, and says to come back if breathing symptoms start. (NICE NG115) See screenings for alpha-1 antitrypsin deficiency.
If spirometry is normal and there are no symptoms, in people who smoke: NICE says they are at higher risk of lung disease and should come back if breathing symptoms start. (NICE NG115) See screenings if you smoke.

What it means for lung cancer screening

NICE and GOLD say emphysema on CT is an independent risk factor for lung cancer. (NICE NG115)(GOLD 2026) The USPSTF bases eligibility for yearly low-dose CT on age 50 to 80, a 20 pack-year smoking history, and smoking now or having quit within the past 15 years; emphysema is not one of the criteria. (USPSTF 2021) If the same scan showed a spot on the lung, see lung nodule found by chance; for calcium in the heart arteries, see heart artery calcium found by chance.

MedlinePlus, when to contact a medical professional: (MedlinePlus)

Go to the emergency room or call 911 or the local emergency number if you have a rapid increase in shortness of breath.

Routine age-based screening

A finding on a scan does not replace the routine screenings for your age; see screenings by age and gender.

Where they differ:

Screening people without symptoms. The USPSTF recommends against COPD screening in adults who do not recognize or report breathing symptoms. (USPSTF COPD 2022) GOLD recommends spirometry for targeted people having lung cancer screening, or when imaging shows changes of airways disease. (GOLD 2026)
Whether to report it at all. NICE recommends considering review and spirometry after an incidental finding. (NICE NG115) The SUMMIT program did not report emphysema back to doctors because its participants routinely had spirometry, and its authors say programs without spirometry should report it with a suggestion to do the test. (SUMMIT 2023)
How strong the evidence is. NICE says there was no evidence on what to do for people with emphysema on a scan but no symptoms, so its advice is based on committee consensus. (NICE NG115)

Your doctor decides what your result means for you.

Questions people ask

Does emphysema on my CT mean I have COPD?

Not on its own. GOLD says a breathing test (spirometry) showing airflow obstruction is needed to diagnose COPD. In one UK screening study, about a third of people with emphysema on CT did not have airflow obstruction. (GOLD 2026) (SUMMIT 2023)

Will I be offered a breathing test?

Often. NICE says to consider a respiratory review and spirometry, and GOLD says emphysema on CT should lead to a check of symptoms and consideration of lung function testing if not done before. Your doctor decides. (NICE NG115) (GOLD 2026)

I feel fine. Should I still mention it?

Yes, you can raise it with your doctor. The USPSTF advice against COPD screening is for adults without symptoms in general, while NICE has separate advice for people whose scan already shows emphysema. (USPSTF COPD 2022) (NICE NG115)

Does emphysema change my lung cancer screening?

The USPSTF bases eligibility on age and smoking history, not on emphysema. NICE and GOLD note emphysema on CT is an independent risk factor for lung cancer. (USPSTF 2021) (NICE NG115) (GOLD 2026)

My report says trace or mild. What does that mean?

Those are visual grades from the Fleischner Society for the most common type, centrilobular emphysema, running from trace and mild up to confluent and advanced destructive. (Fleischner 2015)