Omental-Mesenteric Myxoid Hamartoma Mimicking Malignancy in a 14-month-old child (A Case Report)

Background: The omental-mesenteric myxoid hamartoma (OMMH) is a very rare lesion, mainly seen in children and characterized by multiple omental and mesenteric nodules, which may be confused with malignant neoplasm. Microscopically, these lesions consist of a richly vascularized myxoid stroma with plump mesenchymal cells. This lesion has a benign clinical course without recurrence during follow up.Case Presentation: We present a 14-month-old boy that was referred with history of abdominal distension, fever and vomiting for 3 months. Enhanced computed tomography (CT) revealed a huge well-demarcated hypodense and spherical mass which displaced bowel loops without obvious penetration to the intestinal walls.Histological and immunohistochemical examinations confirmed the diagnosis of OMMH.No evidence of recurrence was noted during 3 years follow up.Conclusion: OMMH is a very rare lesion and because of its aggressive appearance, differential diagnosis with malignancy is warranted. The clinical picture of our case also led to high suspicion of malignancy. However by consideration of histological and immunohistochemical findings we could achieve the correct diagnosis.