Pancreatic lipomas are uncommon mesenchymal tumors of the pancreas.
Rarely symptomatic, they are more often detected incidentally on cross-sectional imaging for another purpose. If they do cause symptoms, it will typically be those related to regional mass effect from the mass.
Mature fat cells with thin internal fibrous septa. It differs from pancreatic lipomatosis in that it has well-defined margins from a thin collagen capsule.
- well-circumscribed, lobulated lesion in the pancreas that measures fat attenuation (HU <-10)
- does not enhance
- well-circumscribed, lobulated lesion in the pancreas that is T1 and T2 hyperintense
- saturates on a fat-saturated sequence
- may not be hypointense on an out-of-phase sequence (edge may show "india-ink" artifact
- difficult to diagnose: may be hyperechoic or hypoechoic
Treatment and prognosis
They are not locally aggressive or metastatic tumors, and only rarely need resected.
- pancreatic mature cystic teratoma (dermoid): even more rare, may have associated calcifications
- liposarcoma: can be considered if there are atypical findings such as an infiltrative lesion, a large lesion, or solid enhancing elements