a Rare Case of Retroperitoneal Bronchogenic Cyst: a case report

We reported a 54-year-old asymptomatic man who received PET-CT scan for physical health examination at our hospital. In PET-CT scan, we incidentally found a left suprarenal tumor located adjacent to diaphragmatic crus with almost no FDG activity. This tumor was cystic in nature and slightly enlarged in size on CT scan one year later. Laparoscopic adrenalectomy and resection of this suprarenal tumor were performed. Histopathologic examination revealed a thinwalled cystic mass lined by ciliated pseudostriated columnar epithelium and smooth muscle fiber which was diagnosed as bronchogenic cyst. Bronchogenic cyst is regarded as a congenital abnormality of the primitive foregut. The most common location is in the mediastinum, particularly posterior to the carina; however, cervical, cutaneous, diaphragmatic, gastric, abdominal, and retroperitoneal bronchogenic cysts have all been described in English literatures [1]. Subdiaphragmat ic bronchogenic cysts are unusual and that reported in English literatures have a tendency to locate on the left of midline. The most common location was within a triangle behind the stomach defined by the midline, the splenic vein, and the spleen/diaphragm [1]. If a cystic tumor locates in this region, bronchogenic cyst should be listed in the differential diagnosis. Contrast-enhanced CT scan or MR image can be useful for differentiating hyperattenuating cysts from soft tissue masses [2].