J Korean Soc Radiol.  2017 Jul;77(1):9-13. 10.3348/jksr.2017.77.1.9.

Imaging Findings of Primary Angiomyolipoma of the Pancreas: A Case Report

• Kim HH
• Park DH

• KMID: 2384729
• DOI: http://doi.org/10.3348/jksr.2017.77.1.9

Abstract

Angiomyolipoma (AML), a part of a family of mesenchymal tumors, is a common fat-containing solid neoplasm. Kidney and liver are the main sites of AML; rarely, primary pancreatic AML has also been reported. Here, we present a case of pathologically proven primary pancreatic AML in a middle-aged female patient, based on multidetector computed tomography scan, endoscopic ultrasound, positron emission tomography, and magnetic resonance imaging findings.

MeSH Terms

Angiomyolipoma*
Female
Humans
Kidney
Liver
Magnetic Resonance Imaging
Multidetector Computed Tomography
Pancreas*
Positron-Emission Tomography
Ultrasonography

Figure

• 

  Fig. 1 A 59-year-old woman with primary angiomyolipoma of the pancreas. A. Axial contrast-enhanced MDCT scan series reveal a well-defined, 2-cm mass in the body of the pancreas without invasion of adjacent organs or vessels and no evidence of internal hemorrhage or necrosis. The mass demonstrates peripheral enhancement during the arterial (first image), pancreatic (second image), and portal venous phases (third image). B. EUS shows a hyperechogenic mass in the body of the pancreas, measuring 2-cm. C. MRI shows high peripheral and intermediate central SI on a HASTE T2-weighted image (first image). Both in-phase (second image) and opposed-phase (third image) images fail to demonstrate chemical shifting. A diffusion-weighted image (fourth image) reveals a high SI area in the pancreas without dark SI on the ADC map. This finding indicated the T2 shine-through artifact. ADC = apparent diffusion coefficient, EUS = endoscopic ultrasound, HASTE = half-Fourier acquisition single-shot turbo spin-echo, MDCT = multidetector computed tomography, SI = signal intensity D. Gross pathologic examination (left photograph) shows a 2 × 2 cm, well-defined, gray-white nodular tumor (white arrow) in the body of the pancreas. Hematoxylin and eosin staining (right photograph, ×100) reveals that the mass is composed of thick-walled blood vessels (open arrow), adipose tissue (black arrows), and spindle cells. Compared with the central area of the tumor, the peripheral area shows low cellularity with fibrinoid-like connective tissue. E. HMB-45 (left photograph) and SMA (right photograph) staining (immunohistochemistry, × 200) show diffusely positive immunoreactivity. Considering these results (D, E), the final pathologic diagnosis of the pancreatic tumor was determined as primary pancreatic AML. AML = angiomyolipoma, HMB-45 = human melanoma black-45, SMA = smooth muscle actin

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