Chronic inflammation in congenital cystic adenomatoid malformations. An underestimated risk factor?

Congenital cystic malformations of the lung are more frequently diagnosed before birth, but guidelines for surgical management of asymptomatic cases are lacking. The aim of this article is to review our 10-year results with antenatally diagnosed congenital cystic adenomatoid malformations (CCAMs) to debate indications for early postnatal surgical management in asymptomatic patients.

Twenty-four cases were reviewed; of these, 18 were operated on before 15 days of life for respiratory distress or mediastinal shift, whereas 6 were submitted to elective surgery at 3 months of age.

Twenty lobectomies and 4 atypical resections were performed. Two of the latter required a second surgery for incomplete primary perinatal resection. No postsurgical complications were reported. Nineteen (19/24) of the resected specimens showed signs of chronic inflammation. In the perinatal period, 100% (8 cases) of CCAM type II and 50% (8 cases) of CCAM type I resulted to be inflamed. Of the asymptomatic cases, 50% (3/6) were also found to be affected. No infections were detected at bacteriologic culture and bacterial debris was stained in 3 specimens.

In this series, a 79% incidence of pulmonary inflammation was detected. The CCAM type II resulted to be always involved in this process of inflammation. This was an unexpected finding, particularly in cases without mediastinal shift or respiratory distress. In light of these results, early postnatal treatment, at around 3 to 6 months of age, could be considered even in asymptomatic patients.