Recurrent Retroperitoneal Lymphatic Malformation in a Pediatric Patient: A Case Report.

Retroperitoneal lymphatic malformations are rare, benign, cystic tumors of the lymphatic system, accounting for 1% of all lymphatic malformation manifestations. Lymphatic malformations are often asymptomatic, but may clinically present with abdominal pain and a palpable mass. Initial diagnostic workup is challenging due to the difficulty of differentiating from masses that may arise from the pancreas, liver, and kidney. This report describes a recurrent retroperitoneal lymphatic malformation in a 15-year-old male. The patient presented with abdominal pain and radiological imaging demonstrated abdominal fluid collection. Following conservative management using aspiration, the patient presented three months later with recurrent abdominal pain. Radiological imaging identified a large thin-walled cystic lesion in the right hemiabdomen containing minimal thin internal septations. Histological analysis confirmed the lymphatic malformation following computed tomography-guided biopsy. The patient underwent aspiration and was referred for outpatient sclerotherapy to prevent future abdominal fluid collection. This case highlights conservative management of recurrent retroperitoneal lymphatic malformation, both on the initial and subsequent presentation.