case_images: PMC11785620_01
case_images: Contrast-enhanced computed tomography. a Image depicting thickening of the perihilar bile duct wall with contrast enhancement (arrow). b Image of an enlarged lymph node next to the perihilar bile duct (arrow)
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case_images: PMC11785620_01_12328_2024_2075_Fig1_HTML.jpg
case_images: Fig1
case_images: Contrast-enhanced computed tomography revealed mild intrahepatic bile duct dilatation, bile duct wall thickening in the perihilar region (Fig. 1a), and a 20-mm mass adjacent to the thickened bile duct (Fig. 1b).
case_images: Magnetic resonance imaging. a The thickened wall of the perihilar bile duct and adjacent mass shows a hyperintense signal on diffusion-weighted imaging (arrow). b Magnetic resonance cholangiopancreatography reveals stricture of the bile duct from the hepatic hilum to the vicinity of the confluence of the cystic duct (arrow), and the upstream bile duct is slightly dilated
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case_images: Fig2
case_images: Magnetic resonance imaging revealed a thickened wall of the perihilar bile duct and the adjacent mass had a hyperintense signal on diffusion-weighted imaging (Fig. 2a). Magnetic resonance cholangiopancreatography revealed a stricture in the bile duct extending from the hepatic hilum to the vicinity of the confluence of the cystic duct, and the upstream bile duct was slightly dilated (Fig. 2b).
case_images: Endoscopic ultrasonography. a The thickened bile duct shows a smooth inner border echo. b The lumen of proper hepatic artery penetrating the thickened wall is preserved. c A 2-cm mass (arrow) is found close to the lesion, which is considered an enlarged lymph node. The boundary between the bile duct and the mass is clear and no continuity is observed
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case_images: Fig3
case_images: Endoscopic ultrasonography revealed a thickened bile duct wall as much as 8-mm in diameter with smooth internal echoes (Fig. 3a) and a proper hepatic artery with a preserved lumen penetrating the wall (Fig. 3b). The boundary between the bile duct and mass was clear, and no continuity was observed (Fig. 3c).
case_images: Endoscopic retrograde cholangiopancreatography. a A relatively extensive, gently rising stricture is observed in the perihilar bile duct (arrow). b In the stenotic area, intraductal ultrasonography reveals a homogeneous wall thickening of 3.5 mm and peroral cholangioscopy shows submucosal tumor-like-circumferential narrowing with mildly irregular and uneven but smooth mucosa, and no severe mucosal irregularities or unevenly dilated blood vessels suggestive of cholangiocarcinoma were observed. c In the non-stenotic area, intraductal ultrasonography reveals no wall thickening and peroral cholangioscopy shows no mucosal irregularity
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case_images: Fig4
case_images: Endoscopic retrograde cholangiopancreatography (ERCP) revealed a relatively extensive and gently rising stricture in the perihilar bile duct (Fig. 4a). Meanwhile, intraductal ultrasonography showed homogeneous wall thickening (3.5 mm) in the stenotic area (Fig. 4b), but no wall thickening in the non-stenotic area (Fig. 4c). Peroral cholangioscopy (POCS) shows submucosal tumor-like-circumferential narrowing in the stenotic area, with mildly irregular and uneven but smooth mucosa, and no severe mucosal irregularities or unevenly dilated blood vessels suggestive of cholangiocarcinoma were observed (Fig. 4b). In the non-stenotic area, POCS reveals no mucosal irregularity (Fig. 4c).
case_images: Pathologic findings of endoscopic ultrasound-guided fine needle aspiration specimens. A diffuse proliferation of large, atypical cells with anisotropic, irregular nuclei is observed by hematoxylin and eosin staining (a). Immunohistochemical staining is positive for CD10 (b), CD20 (c), and BCL-6 (d) and negative for CD3 (e) and MUM-1 (f), consistent with diffuse large B-cell lymphoma, germinal center B-cell-like subtype
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case_images: Fig5
case_images: Diffuse proliferation of large atypical cells with anisotropic and irregular nuclei was observed in the biopsy specimens (Fig. 5a). Immunohistochemical staining was positive for CD10, CD20, and BCL6, and negative for CD3 and MUM-1 (Fig. 5b-f).