Cystic lymphangiomas (cystic hygromas) are comparatively rare tumors. Seventy-five percent of these lesions are in the neck, 20% are in the axillary region, and 5% are in the mediastinum, retroperitoneal region, pelvis, or groin. Rarest are retroperitoneal cystic lymphangiomas. Beahrs et al 1 reported nine cases of such tumors diagnosed at the Mayo Clinic from 1911 to 1947. Rauch 2 found 22 cases of retroperitoneal lymphangiomas reported before 1959. Kafka and Novak 3 added 10 cases and reported one of their own. Recently, Singh et al 4 described another case, bringing the total number of reported cases of retroperitoneal cystic lymphangiomas to 34. We report two cases with unusual features: one patient had preoperative angiograms, the second patient had an acute condition within the abdomen.