Congenital cystic adenomatoid malformation type 4.

A 9-day-old boy presented in respiratory distress and with failure to thrive. The chest X-ray showed a hyperlucent area of the left lung. A resection of the markedly emphysematous segment 2 of the left upper lobe was performed assuming the emphysematous tissue was due to congenital lobar emphysema (CLE). Histological examination of the lung tissue, however, revealed a pattern consistent with congenital cystic adenomatoid malformation (CCAM) type 4. The therapy for CLE as well as for CCAM is similar, i.e., resection of the emphysematous tissue. As far as the prognosis is concerned, it is important to diagnose the exact type of malformation in order to exclude associated anomalies, as well as the risk of development of malignancies in later life. The frequency of associated malformations of CCAM type 4 is unknown. Although the risk for development of malignancies from CCAM type 4 is not clear at the moment, the possible development of malignancies justifies prompt resection shortly after diagnosis, even in asymptomatic patients. A life-long follow-up in those patients who had a resection of CCAM in early childhood is recommended.