Long-term outcome of asymptomatic patients with congenital cystic adenomatoid malformation.

PURPOSE: Congenital cystic adenomatoid malformation (CCAM) represents a rare congenital anomaly of the lung. It remains controversial whether patients with asymptomatic lesions warrant early surgical intervention. Our aim was to review the outcome of asymptomatic CCAM patients at a paediatric tertiary centre.

METHODS: The medical case notes of all children with CCAM presenting to our institution between 1986 and 2007 were reviewed. Data on pre- and post-natal investigations, clinical presentation, lesion site, type of surgical procedure, timing, and outcomes of surgery were reviewed.

RESULTS: A total of 35 patients were diagnosed with CCAM during the 21-year study period (1986-2007). Sixty percent (n = 21) were asymptomatic at birth including eight patients with prenatal ultrasound scan confirming CCAM. In this group, 18 patients (86%) subsequently developed symptoms (median age 2 years, range 1 month-13 years) and required surgery. Symptoms included pneumonia with or without infected CCAM (43%), respiratory distress (14%) and spontaneous pneumothorax (14%). Eight patients underwent multiple hospital presentations with complications related to CCAM. Of the 21 initially asymptomatic patients, 17 (81%) underwent surgical resection. Only one of these patients was completely asymptomatic prior to surgery. There were eight post-operative complications and no mortality. One patient underwent a second thoracotomy for residual CCAM. The median length of hospital stay was 9 days (range 3-32 days).

CONCLUSION: This study suggests patients who present with asymptomatic CCAM will subsequently become symptomatic. Early surgical referral and intervention may be beneficial to avoid the development of complications.