Successful Resection of a Large Duplication Cyst by Retropleural Thoracotomy Approach in a 3-Month-Old Infant: A Rare Case from Kabul, Afghanistan

Background: Duplication cysts are rare congenital malformations arising from developmental anomalies of the primitive foregut, with an incidence of approximately 1 in 8,200 live births. These cysts may present at any point along the esophagus but most commonly occur in the upper thoracic region. Case Presentation: This report presents a rare case of a large thoracic duplication cyst in a 3-month-old female infant who presented with respiratory distress and cyanosis. Imaging studies, particularly CT scan, revealed a large cystic mass in the posterior mediastinum. Surgical excision was performed via retropleural thoracotomy, which allowed for complete removal without the need for chest tube placement. Histopathology confirmed the diagnosis of an enteric duplication cyst. The patient showed excellent postoperative recovery with resolution of symptoms. Conclusion: Duplication cyst are rare congenital abnormality which differentiating the cyst from other malignant tumors is highly recommended in the beginning. The best initial choice for diagnose of duplication cyst is CTs. Retropleural thoracotomy in this case successfully helped to remove the cyst from the thoracic region without any complications. the the importance of diagnosis, differential diagnose, appropriate surgical planning, and individualized surgical approach in managing complex congenital thoracic anomalies in infants.