Not every retroperitoneal mass is malignant

Abstract

Background: Cystic lymphangioma is a rare benign tumor of the lymphatic system, most commonly observed in the neck and axilla (in 95% of cases). Less than 1% of lymphangiomas occur in the retroperitoneum. Case report: A 46-year-old female was evaluated for bilateral flank pain, asthenia, and dyspnea with a one-year history. Abdominal computed tomography scan revealed an extensive conglomerate of lymph nodes in the middle retroperitoneum with a predominantly cystic appearance. An excisional biopsy confirmed the diagnosis of cystic lymphangioma on anatomopathological examination. Due to compression of retroperitoneal structures, an almost total cytoreductive surgery was proposed. However, in the immediate postoperative period, the patient developed thrombosis of the left renal vessels, resulting in renal hypoperfusion. No disease recurrence was observed after 3 years of follow-up. Conclusion: This case presents a rare occurrence of cystic lymphangioma in adults, highlighting the importance of considering this entity in the differential diagnosis of retroperitoneal lymphatic masses.