Objectives The purpose of this study was to evaluate diagnosis, clinical signs and strategy in Congenital Cystic Adenomatoid Malformations (CCAM). Methods In this retrospective study, patients with thoracic surgery for CCAM lesions at the University Hospitals of Leuven from July 1993 to July 2016 were searched. Data on diagnosis, prenatal ultrasound findings, clinical signs, lesion site, CCAM type, associated anomalies, imaging, surgical approach and postoperative morbidity were reviewed. The Fisher’s exact and Mann–Whitney tests were used as appropriate. Results A total of 55 patients were identified with CCAM. In 65% (n = 36/55), CCAM was detected on prenatal ultrasound. Prenatal symptoms due to hydrops or mass-effect were present in 22% (n = 8/36), of which eventually 6 had need for prenatal intervention (Thoracoamniotic shunting or Intrauterine Puncture). Surgery was performed elective in 40% patients (n = 22/55), while others developed clinical signs with need for semi-urgent surgery, with clinical signs of pulmonary infection and respiratory distress being the most common. Most patients had a single lobectomy via mini-thoracotomy. Postoperative complications and length of stay were observed to be significantly higher in CCAM with preoperative clinical signs. Conclusions Surgery in asymptomatic CCAM patients can be performed safely with few postoperative complications and can be planned at young age in patients with high risk of developing clinical signs later in life.