PMC2636813_01
Contrast-enhanced CT shows the markedly dilated CBD and 2 enlarged lymph nodes in the peripancreatic region. (a) The marked dilated CBD (arrow) and one of 2 enlarged lymph nodes near the upper border of the pancreas (arrow head) are detected. (b) Another enlarged lymph node near the lower border of the pancreas (arrow head) is found.
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F1
Contrast-enhanced computed tomography (CT) revealed marked dilatation of the common bile duct (CBD) and 2 enlarged lymph nodes in the peripancreatic region (Figure 1-a, b). We did not perform frozen slide examination of the lymph nodes in the peripancreatic region before the resection, since the images of those enlarged lymph nodes (e.g. round shape and well-enhanced) shown by contrast-enhanced CT were typical for metastasis from carcinoid tumor as shown in Figure 1-a, b.
Endoscopy shows a slightly enlarged ampullary region, suggesting the existence of a submucosal tumor because the epithelium has a normal appearance.
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F2
Endoscopy showed that the ampulla was slightly enlarged by a submucosal tumor, although its epithelium had a normal appearance (Figure 2).
ERCP shows severe stenosis of the distal portion of the CBD and marked proximal dilation. The main pancreatic duct is not dilated.
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F3
Endoscopic retrograde cholangiopancreatography (ERCP) also demonstrated a markedly dilated CBD with moderate stenosis in its distal portion (Figure 3).
(a) The resected specimen contains a small yellowish submucosal tumor (approximately 7 mm in diameter) located at the ampulla of Vater (arrow). (b) Monotonous tumor cells with small round nuclei are seen (hematoxylin and eosin staining, x 400). (c) Carcinoid tumor cells within a peripancreatic lymph node (x 200). (d) The tumor cells are positive for synaptophysin, a neuroendocrine marker (x 40). (e) Endolymphatic tumor emboli are shown by staining with D2-40 antibody (x 400). (f) Positive staining for MIB-1 antibody is seen in approximately 3.2% of the tumor cell nuclei (x 400).
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F4
The resected tumor was a small yellowish submucosal mass (7 mm in diameter) located at the ampulla of Vater (Figure 4-a). Tumor cells were detected under the ampullary epithelium, spreading over the sphincter of Oddi to reach the muscularis propria, and infiltrating into the CBD wall to create submucosal thickening (Figure 4-b). The tumor cells were also found in 2 peripancreatic lymph nodes (Figure 4-c). The tumor cells were strongly stained by synaptophysin antibody (Figure 4-d. Immunohistochemical staining using D2-40 antibody showed lymphatic involvement (Figure 4-e), and the Ki-67 labeling index of the tumor cells determined with MIB-1 was 3.2% (Figure 4-f) and overexpression of p53 was not detected.