Retroperitoneal lipoma; a benign condition with frightening presentation

INTRODUCTION: lipoma is the most frequent soft tissue tumor in adults. Its occurrence in the retroperitoneal region is extremely rare. The aim of this study is to report a case of retroperitoneal lipoma with a literature review. PRESENTATION OF CASE: A 34-year-old female presented with abdominal distension and severe back pain for one year duration. She also reported weight loss and constipation. The examination revealed asymmetrical abdominal distension and everted umbilicus. There was a big irregular mass occupying the whole abdomen reaching into the xiphisternum, firm in consistency, smooth surface, and well defined borders. Abdominal ultrasound demonstrated a large retroperitoneal heterogeneous mass. Computed tomography (CT) scan showed a large well defined hyperechoic mass with fibrous septa extending from the left ovary up to the diaphragm. Exploratory laparotomy revealed a giant clearly demarcated fatty tumor adherent to the retroperitoneal fatty tissues. The histopathological examination of the specimen confirmed the diagnosis of the retroperitoneal lipoma. DISCUSSION: Retroperitoneal lipomas have been reported in various age groups; namely children, middle and old age patients. Based on the characteristic radiological features of the tumor, enormous diagnostic work-up is not justified. CONCLUSION: Retroperitoneal lipoma is a very rare variant of lipoma, presents with various signs and symptoms that may be misleading. Radiologic imaging especially CT scan is the diagnostic tool of choice. Surgical resection is the main modality of management.