The Outcome of Expectant Management of Congenital Cystic Adenomatoid Malformation of the Lung

To the Editor,

We read with deep interest the article by Hammond et al. on the outcome of CCAM in the Northern region of England between 1985 and 2006 [1]. The authors reviewed the experience in the Northern region of England in the management of CCAM by searching multiple databases on congenital anomalies, thoracic surgery records and hospital coding. They identified 62 patients suspected as having CCAM during the study period; however 25 cases were excluded from further analysis because of a lack of histological confirmation (following surgery or post-mortem) or because they did not undergo CT scan to confirm diagnosis.

The authors tried to evaluate the sensitivity of prenatal ultrasound for the detection of CCAM; however the study was not designed for this purpose. In fact, Hammond and colleagues included only prenatally suspected CCAM, while excluding foetuses with other possible differential diagnoses (CDH, BPS, CLE). This selection does not permit a proper quantification of false positive and negative cases, which would influence sensitivity.

The reported high rates of pre- and perinatal mortality (14 patients (35%) overall, of which 8 were intrauterine deaths/terminations of pregnancy and 6 were early neonatal deaths) seems to be too high according to international reports. We previously reported on 57 consecutive cases of surgically corrected CCAM. Of these, 43 (75%) infants had a prenatal diagnosis of CCAM, with no intrauterine deaths/terminations of pregnancy and with only 1 case of early neonatal death (2%) [2]. In our experience of more than 20 years of counselling for prenatally diagnosed malformations, termination of pregnancy for CCAM was not higher than 5% of all cases (unpublished data), and intrauterine death was even lower, occurring only in rare cases of foetal hydrops secondary to massive CCAM. The available literature seems to agree with our finding, defining CCAM as a usually benign lesion [3]. It might be of interest to know what the prenatal counselling policy for CCAM is in the Northern region of England, based on the assumption that more than one third of foetuses/newborns may have an early death.

Finally, Hammond and co-workers proposed a wait-and-see policy for prenatally detected CCAM. We do not agree with this opinion because we previously demonstrated that patients operated for symptomatic CCAM experienced more complications and had a more demanding postoperative course [2].

References

• 1 Hammond PJ, Devdas JM, Ray B. et al . The outcome of expectant management of congenital cystic adenomatoid malformations (CCAM) of the lung.  Eur J Ped Surg. 2010;  20 145-149
• 2 Conforti A, Aloi I, Trucchi A. et al . Asymptomatic congenital cystic adenomatoid malformation of the lung: Is it time to operate?.  J Thorac Cardiovasc Surg. 2009;  138 826-830
• 3 Calvert JK, Boyd PA, Chamberlain PC. et al . Outcome of antenatally suspected congenital cystic adenomatoid malformation of the lung: 10 years’ experience 1991–2001.  Arch Dis Child Fetal Neonatal Ed. 2006;  91 F26-F28

Correspondence