Transabdominal laparoscopic excision of a giant retroperitoneal lymphangioma.

Retroperitoneal lymphangioma is exceptionally rare. We present a case of a 41-year-old asymptomatic patient with a large abdominal cystic mass detected on contrast-enhanced computed tomography (CT) scan, initially suspected to be pseudomyxoma peritonei. Laparoscopic exploration revealed a 30 x 30 cm multilocular cystic tumour originating from the retroperitoneum. The tumour was successfully resected laparoscopically, and pathological analysis confirmed a lymphangioma. The patient recovered well with no recurrence over five years. For uncertain tumour types, transabdominal laparoscopic exploration should be prioritised. For treating retroperitoneal lymphangiomas with the origin in the retroperitoneum and a main body in the abdominal cavity, the transabdominal laparoscopic approach is a less invasive and effective treatment option.