A rare case of a retroperitoneal lympangioma causing chronic flank pain in an adult

Retroperitoneal lymphangiomas are exceedingly rare and typically asymptomatic. We present a case of a 27 year-old female with chronic right flank pain and cross-sectional imaging showing a large multi-cystic mass located medial and inferior to the right kidney. The patient underwent an uncomplicated robotic-assisted, laparoscopic resection of the mass with final pathology showing a benign lymphangioma. This case highlights the importance of recognizing retroperitoneal lymphangiomas as atypical causes of chronic flank pain and demonstrates that these benign tumors can be successfully resected robotically. Given today's urology residency training, urologists are likely uniquely positioned to best manage these peri-renal lymphatic malformations.