Congenital pulmonary airway malformation (CPAM)

If your child has been born with a congenital lung abnormality, or a lung abnormality such as congenital pulmonary airway malformation (CPAM) has been detected on a scan before birth, you may have lots of questions.

On this page we answer common questions from parents, including:


What are congenital lung abnormalities?

Congenital lung abnormalities are problems that your baby is born with. They happen when tissues in the lungs or airways haven’t developed properly.

There are several different types of congenital lung abnormality. For example, there could be a problem with:

  • the lungs
  • the airways
  • the blood supply to the lungs or the airways

What are congenital pulmonary airway malformations (CPAM)?

CPAM are lesions (abnormal areas of tissue) on the lung that happen when the airway does not develop properly. They are the most common type of congenital lung abnormality. Most babies with CPAM can be delivered normally and will not have any obvious symptoms.

CPAM are usually detected before your baby is born, at the 20-week prenatal scan.

There are different types of CPAM, and your child may be affected by more than one type. Doctors may not know exactly which type of CPAM your baby is affected by until a few months after birth. At this time, your child can have a scan to find out what’s going on in their lungs. A chest CT scan with an injection of dye will show exactly what is causing the abnormality. A type of dye called contrast is injected to help the blood vessels show up on the scan. The injection will only last a second, and the scan itself is painless.

Types of congenital lung abnormality that look like CPAM on the scan include:

  • absent bronchus (bronchial atresia): one or more peripheral bronchi (airways at the very end of the bronchial tree) is missing
  • bronchogenic cysts: pockets of tissue called cysts that develop on the bronchial tree (the system of airways called bronchi and bronchioles)
  • bronchopulmonary sequestration: a mass of abnormal lung tissue develops next to the lung, or inside one lung. It is usually solid rather than air filled. This does not function or connect with the rest of the breathing system
  • congenital cystic adenomatous malformation (CCAM): pockets of tissue called cysts that develop in one or more lobes (sections) of the lung
  • congenital lobar overinflation (CLO): one of the sections of the lung called the lobes gets overinflated. This squashes and moves the lung tissues next to it and causes breathing difficulties. It’s sometimes known as congenital lobar emphysema (CLE) or congenital large hyperlucent lobe (CLHL)
  • foregut duplication cyst: early in the life of an unborn baby, some immature parts of the lung develop abnormally. At first, in the very early stages of development, the lung bud (which goes on to form the lungs) grows out of what will become the gut. Some lung cystic abnormalities therefore look like parts of the intestine when removed and examined under a microscope

CPAM and cancer

A rare cancer of young children known as pleuropulmonary blastoma (PPB) can sometimes look like a CPAM. If a CPAM has been diagnosed at your prenatal scan, it is very unlikely to be a PPB. Once your baby is born, if doctors find a cystic-looking CPAM with a pneumothorax,  doctors will consider this very rare diagnosis and carry out tests to check for PPB.

Lung cancers have been reported in some young adults within a CPAM. Some experts have suggested long-term (chronic) infection could be the cause of a cancer developing inside a CPAM, but this is not proven. It is likely that the increased risk of cancer is low.


How common are CPAM and other congenital lung abnormalities?

Congenital lung abnormalities are rare. Researchers estimate they may affect about one in every 2,000 babies born.

There are many different types of congenital lung abnormality. Each type is very rare. We don’t have accurate figures for how common each individual abnormality is, but CPAM is the most common.


What causes congenital lung abnormalities?

We do not always know what causes congenital lung problems.

Some congenital lung abnormalities happen together with other congenital abnormalities, such as heart problems.

Researchers are working to understand more about how congenital lung abnormalities happen. In some cases, they have identified faulty genes and processes that cause the lungs to develop abnormally.


What are the symptoms of congenital lung abnormalities?

Children’s symptoms will vary depending on the condition. Congenital lung abnormalities may be detected before birth, in a newborn baby or later in life.

Some people live with congenital lung abnormalities for a long time without having any symptoms at all. Their condition might be discovered by chance, when they have a chest X-ray for different reasons.

Before birth

In some babies, congenital lung abnormalities may be picked up on antenatal scans before they are born. This is usually the case with CPAM.

Newborn babies

Most babies with CPAM have no obvious signs of chest problems.

Some babies with other congenital lung abnormalities will have breathing problems as soon as they are born. Symptoms can include:

Sometimes a baby may have significant breathing difficulties and may need help with their breathing (Tommy's website). This might include ventilation, or taking oxygen through a face mask or a pair of small prongs by their nostril.

Older children and adults

Most children with CPAM will not experience symptoms.

In older children and adults, symptoms of congenital lung abnormalities can include:

  • recurrent infections in the affected area of the lung
  • bronchiectasis
  • asthma-like symptoms that do not respond to asthma treatment.

How are congenital lung abnormalities diagnosed?

Lung problems can sometimes show up on an ultrasound scan, when the baby is still in the womb. This is usually the case with CPAM.

Other congenital lung problems are diagnosed after birth. Your child may have an X-ray and a high-resolution CT scan to look at their lungs.

Doctors might use a bronchoscopy (a test to look inside the airways) if they think your child may have an airway abnormality.


How are congenital lung abnormalities treated?

Babies and children with CPAM and other congenital lung abnormalities will usually go to specialist centres to investigate and manage their condition. If the abnormality is detected on an antenatal scan, the pregnancy will be monitored, and arrangements may be made to deliver the baby in a specialist centre.

Treatment before birth

Sometimes babies can have treatment before birth (antenatal treatment).  For example, in unborn babies with a bronchopulmonary sequestration (where abnormal blood vessels grow that do not connect with the rest of the breathing system), doctors might block the abnormal vessels while they are still in the womb.

Treatment after birth

Treatment after birth will depend on your child’s condition and symptoms.

Some babies with congenital lung abnormalities may need emergency surgery when they are newborn. Others may choose to have an operation due to concerning features on a CT scan, or following any complications that may develop.

Babies without symptoms may or may not need surgery. If, as your child grows up, they do not have any symptoms, they may not need immediate treatment. They may have regular check-ups to keep an eye on the condition. This is called watchful waiting.

Most children with CPAM have no clear signs of chest problems, but some develop frequent chest infections.

With CPAM, the lungs can’t always stay clean as they normally would, so infections can develop. Children can have a long term (chronic) cough and poor growth because of this. This could be a reason to perform surgery.

Doctors agree that if a child with a CPAM has symptoms then the CPAM should be removed surgically. Most surgeons will hope to perform surgery using keyhole techniques.

The complications from surgery are possible bleeding, air leak needing a chest drain and infection in the tissues.

Other than surgery, your child will need treatment for any complications that happen related to their congenital lung abnormality. For example, they will need antibiotics if there is an infection in the affected area.


Where can I get more information and support?

Learning that your child has a lung problem can be very worrying. Our information on When your child is diagnosed with a lung condition offers advice on how to talk to medical professionals and where to access support.

If you have concerns or need advice, call our helpline on 03000 030 555 between 9am and 5pm on a weekday or email them.

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