PMC5247283_01
PMC5247283_02
Abdominal CT showing a hypervascular retroperitoneal mass arising from the peripancreatic region.
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Contrast enhanced computed tomography (CT) of the abdomen and pelvis showed a solid, homogenous, hypervascular and well-delineated mass measuring 48 x 50 mm located in the retroperitoneum behind the body of pancreas (Fig. 1).
Macroscopic findings: an encapsulated mass measuring 5 x 6 x 3 cm with a yellowish grey color.
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On gross examination, it was an encapsulated mass, measuring 5 x 6 x 3 cm with a yellowish color and a multinodular cut surface (Fig. 2).
Lymphoid follicles with features of onion peel cell deposition with Inter-follicular areas showed extensive hyaline vascular stromal changes (HEx40).
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Microscopic examination showed enlarged lymphoid follicles with onion peel like appearance characterized by atrophic germinal centers with surrounding concentric rings of B-lymphocytes (Fig. 3).
Regressed germinal centers with hyperplastic dendritic cells and surrounded by concentric rings of B-lymphocytes (HEx200).
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Inter-follicular areas showed extensive hyaline vascular stromal changes without aggregates of plasma cells (Fig. 4).
Immunostaining for CD23 demonstrated the characteristic follicular dendritic network of residual germinal centers.
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CD23 demonstrated the follicular dendritic network of residual germinal centers (Fig. 5). CD10 was also weakly positive in some of the transformed germinal centers and immunostaining for HHV-8 was negative.