Abstract
Lymphangioma is an uncommon benign lesion typically observed in childhood, with rare occurrences in adults. The preferred treatment for this condition is surgical resection, which offers an excellent prognosis and minimal risk of recurrence when complete removal is achieved. This case report describes the successful surgical management of a rare omental lymphangioma in a 26-year-old man who presented with epigastric pain and abdominal distension. Diagnostic imaging revealed a massive multiloculated cystic lesion measuring 9.0 × 21.3 × 26 cm occupying the entire omentum, with evidence of partial rupture and hemorrhagic fluid. The patient underwent complete surgical excision via midline laparotomy, which required partial gastrectomy due to tumor adherence to the stomach. Histopathological examination confirmed the diagnosis of lymphangioma, and the patient recovered well with no recurrence at 12-month follow-up. This case highlights the diagnostic challenges of adult-onset abdominal lymphangiomas and underscores the importance of complete surgical resection as the definitive treatment. Large omental lymphangiomas can present significant surgical challenges and require careful preoperative planning with advanced imaging and consideration of adjacent organ involvement.