A huge pancreatic lipoma mimicking a well-differentiated liposarcoma: A case report and systematic literature review

Abstract

BACKGROUND Pancreatic lipomas are thought to be very rare. Lipomas are usually easy to identify on imaging, particularly via computed tomography (CT). But sometimes it's quite difficult to distinguish a lipoma from a well-liposarcoma without histologic result. CASE SUMMARY Here, we present a case of pancreatic lipoma in a 59-year-old female. She was asymptomatic and had no medical history of note. CT and magnetic resonance imaging revealed a mass like well-differentiated liposarcoma in the pancreatic head, positron emission tomography/CT showed a low fluorodeoxyglucose uptake and laboratory tests revealed elevated transaminase and carbohydrate antigen-199 levels. Finally, the patient underwent a pancreaticoduodenectomy. Histologically, mature adipocytes were noted in the bulk of the tumor. Accordingly, the pathologic diagnosis of the pancreatic neoplasm was lipoma. To our knowledge, this case is the first example of a suspected well-differentiated liposarcoma that was actually a pancreatic lipoma. We also highlight the radiological features distinguishing a pancreatic lipoma from a pancreatic liposarcoma and briefly review the literature. CONCLUSION Pancreatic lipomas show no obvious gender bias and most commonly occur in the head of the pancreas, of which the maximum diameters are often less than 5 cm, and small, asymptomatic non-compressed lipomas require follow-up only. Surgical excision should be considered when the tumor has compressed important tissues or is difficult to distinguish from a liposarcoma, the choice of surgery depends on the intraoperative presentation.