Diagnosis of Langerhans cell histiocytosis via percutaneous liver biopsy

Background: The aims were to assess the clinical and histopathological characteristics of Langerhans cell histiocytosis (LCH) based on percutaneous liver biopsy and to improve the technique’s diagnostic accuracy. Methods: Data from seven patients were collected. The clinicopathological features and immunophenotypes of hepatic LCH in the biopsied tissues were evaluated . Results: Five men and two women (median age: 21 years) were included. The clinical presentations and imaging findings were unremarkable. In terms of the histological findings, multifocal and solitary lesions were detected in six patients and one patient, respectively. All lesions were located in the portal area and exhibited either enlarged or normal portal tracts. In four patients, Langerhans cells (LCs) were distributed either in clusters or scattered among mixed populations of inflammatory cells.LC invasion of the bile duct epithelium was detected in all but one patient; that individual presented with sclerosing cholangitis (SC) in the absence of LCs. One patient had a similar inflammatory myofibroblastic tumor (IMT) or inflammatory pseudotumor-like follicular dendritic cell (FDC) tumor. One patient had suppurative cholangitis with abscess formation, accompanied by a small degree of LC invasion into the bile duct epithelium. Conclusions: The morphology of liver LCHs varied among patients. Bile duct epithelial damage accompanied by eosinophilic infiltration, a history of extrahepatic LCH, or central diabetes insipidus are clues that LCH may be present; however, H&E staining and IHC are crucial for its diagnosis. LCH should be differentiated from hepatic parasitic infections, primary SC, inflammatory pseudotumor-like FDC tumors, and inflammatory myofibroblastoma.