PMC3283461_01
Fixed, paraffin-embedded tissue sections of i) pancreatic invasion (A, case n 1, magnification at x100) of medium sized cells, with CD43 positive expression signing myeloid lineage, inset shows contiguous lymph node with high CD43 expression (internal positive control of myeloid lineage); and of ii) omentum invasion (B, case n 2, hematoxylin and eosin staining, magnification at x400) by myeloid-like cells, some with mitotic activity (arrow head), surrounding fat cells (arrow), inserts show myeloperoxydase (MPO), CD43, and CD34 expression (arrow head showing internal positive control with vessel).
1477-7819-10-13-1.jpg
PMC3283461_01_1477-7819-10-13-1.jpg
F1
Histological examination of the surgical specimen revealed a pancreatic GS based on the presence of cells of myeloid lineage with positive immunostaining for CD43 myeloid-associated antigen (Figure 1A), whereas immunostainings for other myeloid markers (CD31, CD34, CD38, CD45, CD99, CD117), B-cell markers (CD20, CD79a), T-cell markers (CD3, CD4), commune B- and T-cell markers (CD30) and myeloperoxidase (MPO) were negative. Histological analysis of the pancreatic mass and peritoneal biopsies revealed extramedullar myeloid tumoral cells with immunohistochemistry positive for MPO, CD43, and CD34 (Figure 1B), as well as CD117 and CD45, and negative for CD79a, CD3, CD2, CD4, CD8 and CD68, leading to the diagnosis of pancreatic GS.
Abdominal computed tomodensitometry, with injection of contrast product, portal sequence. Axial (A) projection showing Wirsung dilatation (arrow head). Axial (B) and frontal (C) projections showing low density pancreatic mass (arrow heads), case n 2.
1477-7819-10-13-2.jpg
PMC3283461_01_1477-7819-10-13-2.jpg
F2
The abdominal CT scan showed a 9-mm Wirsung duct dilation (Figure 2A) within the 30-mm mass of the pancreatic head (Figure 2B, C), the tumoral or inflammatory nature of which was uncertain.