A Rare Presentation of Omental Lymphangioma Masquerading as Malignancy in an Adult Patient

Abdominal lymphangiomas are benign vascular neoplasms of the lymphatic vessels. Most are believed to be congenital, and they rarely present in the abdomen in adults. Omental lymphangiomas, in particular, are especially rare and can masquerade as malignancy, which requires further invasive workup. We report the case of an otherwise healthy man with abdominal discomfort, ascites, and a presentation initially concerning for malignancy. However, imaging and pathologic analyses later elucidated the lesion as an omental lymphangioma requiring different management. Treatment options are either resection or sclerotherapy, and the prognosis is generally excellent.