Complicated course of biliary inflammatory myofibroblastic tumor mimicking hilar cholangiocarcinoma: A case report and literature review

Abstract

Background: The inflammatory myofibroblastic tumor (IMT) is a rare, idiopathic, usually benign, mass-forming disease with myofibroblastic proliferation and a varying amount of inflammatory cells. Although it can affect various organs, the biliary tract is a rare localization of primary IMT, clinically, endoscopically and radiologically imitating cholangiocarcinoma. The treatment options are based only on clinical practice experience.

Case summary: A 70-year-old woman was referred to our center due to progressive fatigue, weight loss, abdominal pain, night sweats, and elevated liver enzymes. Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP) revealed proximal common hepatic duct and hilar biliary strictures extending bilaterally to lobular bile ducts. Although initial clinical, endoscopic and radiological signs were typical for hilar cholangiocarcinoma, histological examination showed no signs of malignancy. In total, 8 biopsies using different approaches were performed (several biopsies from dominant stricture during ERCP and direct cholangioscopy; ultrasound-guided liver biopsy; diagnostic laparoscopy with liver and lymph node biopsies). Histological examination revealed signs of IMT, and the final diagnosis of biliary IMT was stated. Although IMT is usually a benign disease, in our case, it was complicated. All pharmacological treatment measures were ineffective. The patient still needs permanent stenting, suffers from recurrent infections and mechanical jaundice. Despite that, the patient already survived 24 mo.

Conclusion: IMT presenting with hilar biliary strictures is a unique diagnostic and clinical challenge as it is indistinguishable from cholangiocarcinoma, and there are no evidence-based treatment options. Our goal is to increase the understanding of this rare disease and its possible course.

Keywords: Biliary strictures; Case report; Hilar cholangiocarcinoma; Inflammatory myofibroblastic tumor; Literature review; Recurrent cholangitis.

Figure 1

Magnetic resonance cholangiopancreatography images at presentation. A: T1 FS late phase contrast-enhanced image showing soft tissue mass with gradual enhancement in the late phase around the wall of the common hepatic duct; B: Three-dimensional magnetic resonance cholangiopancreatography images showing a mass extending to segmental intrahepatic ducts on both lobes with dilatation of peripheral ducts.

Figure 2

Endoscopic retrograde cholangiopancreatography and direct cholangioscopy images. A: Endoscopic retrograde cholangiopancreatography image showing proximal common hepatic duct (CHD) stricture (arrow) involving hepatic confluence with complete obstruction of the right hepatic duct; B: Direct cholangioscopy endoscopic image showing stricture of the proximal CHD.

Figure 3

Magnetic resonance cholangiopancreatography images 3 mo later. A: Three-dimensional magnetic resonance cholangiopancreatography (MRCP) images showing a common hepatic duct stricture (arrow) extending to intrahepatic segmental ducts extent to similar extent as on the previous MRCP with peripheral duct dilatation; B: FS contrast-enhanced images showing a cluster of rim enhancing lesions most likely small abscesses due to cholangitis (arrows); C: Enlarged cardiophrenic lymph nodes (arrow).

Figure 4

Histological images. A, B: The tumor is formed of disordered myofibroblasts and fibroblasts. Focal abundant polymorphonuclear infiltration can be seen (top and bottom left) (HE x 200); C: Negative ALK-1 immunohistochemical reaction.

Figure 5

Carbohydrate antigen 19-9 dynamics during the treatment. CA 19-9: Carbohydrate antigen 19-9; ERCP: Endoscopic retrograde cholangiopancreatography.

Figure 6

Computed tomography images 22 mo after the initial diagnosis. A: Reformatted two-dimensional computed tomography (CT) images in the portal venous phase showing a contrast-enhancing soft tissue mass (arrow) arising from the gall bladder fundus and extending into colon mesenterium; B: Axial CT portal venous phase images showing a large lymph node (arrow) in the right lung hilum.

Figure 7

Case history timeline. MRCP: Magnetic resonance cholangiopancreatography; CHD: Common hepatic duct; IMT: Inflammatory myofibroblastic tumor; ERCP: Endoscopic retrograde cholangiopancreatography; IPT: Inflammatory pseudotumor; MTX-V: Methotrexate-vinorelbine; CT: Computed tomography; GB: Gallbladder.