Is congenital cystic adenomatoid malformation a premalignant lesion for pleuropulmonary blastoma?
BACKGROUND
The relationship between congenital cystic adenomatoid malformation (CCAM) and pleuropulmonary blastoma (PPB), whether causal, correlational, or coincidental, remains controversial. There is a lack of consensus as to the optimal treatment of patients with asymptomatic CCAM.


METHODS
We reviewed all cases of CCAM and PPB seen at our institution from 1999 to 2008. Institutional Research Ethics Board approval was obtained. The incidence of CCAM and PPB, respectively, was calculated based on birth numbers during the study period.


RESULTS
Seventy-four CCAMs were resected over the study period in 129 children diagnosed with CCAM. Five PPBs were diagnosed during the study period. Three of the 5 PPB cases were initially diagnosed as CCAMs. These PPBs were not clinically or radiologically distinguishable from CCAMs. In our referral area, the incidence of CCAM was 1 in 12,000; and the incidence of PPB was 1 in 250,000 live births. The mortality rate for PPB in this cohort was 20%.


CONCLUSIONS
Asymptomatic cystic lung malformations represent a therapeutic dilemma. In this cohort, the incidence of PPB among apparently benign lung lesions was 4%. No clinical or radiological markers differentiated benign CCAMs from PPBs. Our experience provides further justification for resection of all CCAMs. This should be discussed with parents until CCAMs and PPBs can be clearly distinguished preoperatively.
Nasr
Ahmed
A
Division of General and Thoracic Surgery, The Hospital for Sick Children, Toronto, Ontario, Canada M5G1X8.
Himidan
Sharifa
S
Pastor
Aimee C
AC
Taylor
Glenn
G
Kim
Peter C W
PC
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D015615:Cystic Adenomatoid Malformation of Lung, Congenital / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D008175:Lung Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D008297:Male; D009864:Ontario / Q000453:epidemiology; D011230:Precancerous Conditions; D015995:Prevalence; D011379:Prognosis; D018202:Pulmonary Blastoma / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends