Incidental pancreatic lipomas: computed tomography imaging findings with emphasis on diagnostic challenges.

Purpose: The purpose of this study was to describe the computed tomography (CT) findings of pancreatic lipomas of 9 cases, with emphasis to diagnostic challenges.

Methods: Between March 2006 and April 2008, 9 patients with pancreatic lipomas that were diagnosed by CT were reviewed in the present study. Clinical data and CT features of these 9 cases were retrospectively analysed. The patient population included 5 men and 4 women, aged 42-81 years (mean age, 65.8 years). The patients were followed up for at least 2 years with control CTs.

Results: In all 9 cases, a well-bordered nodular fat density lesion was incidentally detected in the pancreas. Four of the lesions had a lobulated contour, and 2 of them had septations. Two of the lipomas were located in the head, 3 in the neck, 3 in the corpus, and 1 in the tail. The CT densitometric values were between -90 and -120 HU, with a mean value of -106 HU. No pancreatic or biliary dilatation or compression to the adjacent structures was seen. All the cases had control CTs, and the lipomas remained unchanged during the follow-up period. Histopathologic confirmation of the diagnosis was not planned for the cases.

Conclusion: Lipomas are rarely encountered in the pancreas. They often are diagnosed coincidentally as small, well-circumscribed, encapsulated, homogeneous, mature adipose masses on imaging studies. Imaging follow-up strategy or histopathologic confirmation is not necessary in asymptomatic patients.