There are two different types of fetal lung masses: the first is a congenital cystic adenomatoid malformation (CCAM) and the other is a bronchopulmonary sequestration.
Congenital Cystic Adenomatoid Malformation (CCAM)
Congenital cystic adenomatoid malformation (CCAM) is a non-cancerous mass usually found on just one side of the lung when the tissue in the lung develops abnormally. These masses can contain fluid-filled cysts. Although the malformation itself is non-cancerous, babies with this condition have a higher incidence of cancer in the lungs. CCAMs also can cause serious infections of the lung. For these two reasons, CCAMs need to be removed some time after birth.
Sequestrations are divided into two categories: extralobar, in which abnormal lung tissue appears outside the normal lung, or intralobar, in which abnormal lung tissue is found inside the lung. Generally, these babies have no other health problems.
A bronchopulmonary sequestration is a section of non-functioning lung that does not connect to the baby's airway and has an abnormal blood supply. In many cases, sequestrations shrink or disappear during pregnancy. In fact, 68% decrease in size or completely disappear before birth.
How Are Fetal Lung Masses Diagnosed?
Fetal CCAM and sequestrations can be diagnosed by ultrasound (sonogram) examination before birth. Evaluation of the lungs is part of the routine ultrasound examination done by many obstetricians as part of their routine prenatal care around the 20th week of pregnancy. Typically, if the obstetrician suspects that the baby has CCAM, the mother will have a series of ultrasounds to track the growth of the mass; if the mass is large, the physicians watch for signs of hydrops (heart failure). Magnetic resonance imaging (MRI) is often used to identify the mass better. Learn about fetal MRI.
How Are Fetal Lung Masses Treated?
After a fetal lung mass is diagnosed, the staff at Ann & Robert H. Lurie Children’s Hospital of Chicago counsels the parents and prepares them for what to expect when their baby is born. Plans are made to assure that the baby is delivered in a hospital that has a neonatal intensive care unit (NICU) with a neonatologist present at delivery.
The majority of babies diagnosed with CCAM are born without any symptoms. If this is the case, then a CT scan is done, and follow-up care continues for about a year. Typically, surgery is scheduled to remove the mass when the child is between 1- and 4-years-old. In selected cases, minimally invasive surgery can be employed to shorten recovery and minimize scarring.
If infants are born with breathing difficulties because of a lung mass, they may need assistance from a breathing machine called a ventilator. Under these circumstances, emergency surgery is performed to remove the mass.
Bronchopulmonary Sequestration Treatment
The majority of babies diagnosed with a bronchopulmonary sequestration also are born with no symptoms. However, even if no symptoms are present, the sequestration is removed by one year of age because it is prone to infection. In selected cases, minimally invasive surgery can be employed to shorten recovery and minimize scarring. Learn about minimally invasive surgery.
A smaller number of infants may have symptoms in the first few days of life that are caused by blood flowing through the abnormal piece of lung tissue. The blood is not able to carry any oxygen in that tissue, which may put a strain on the heart. In these children, surgery to remove the abnormal area is performed in the first few months of their lives.
What Are the Long-term Effects of Fetal Lung Masses?
The long-term outlook for these children is very good if they have the CCAM or sequestration removed. Typically, they lead healthy lives with normal life expectancy. When not removed, both sequestrations and CCAMs have been found to cause serious lung infections. Furthermore, CCAMs left untreated increase the risk of lung cancer in childhood and, perhaps, as an adult.