Inflammatory myofibroblastic tumor of the distal common bile duct: Literature review with focus on pathological examination

Abstract

Inflammatory myofibroblastic tumor (IMT) of the biliary tract is rare, and often difficult to diagnose or to distinguish from other tumors due to its atypical clinical presentation and nonspecific radiological features. Histologically, IMTs are (myo)fibroblastic neoplasms with a prominent inflammatory infiltrate. They are characterized by receptor tyrosine kinase gene rearrangements, most often involving an anaplastic lymphoma kinase (ALK) translocation. The final diagnosis of IMT depends on histopathology and immunohistochemical examination. In this manuscript, we provide a clinical and morphomolecular overview of IMT and the difficulties that may arise in using immunohistochemical and molecular techniques in diagnosing IMT.

Keywords: Inflammatory myofibroblastic tumor; Fluorescence in situ hybridization; Next-generation sequencing; Mesenchymal tumors of the gastrointestinal tract

Core Tip: Inflammatory myofibroblastic tumor (IMT) of the intrapancreatic biliary tract is rare and often difficult to diagnose. In this manuscript, we give a recent update of the clinicopathological features of IMT with focus on the pathological and molecular characteristics.