Progression from early to advanced stage of immune-related cholangitis.

AIM: We report a rare case of immune-related cholangitis in which the natural course could be demonstrated. CASE PRESENTATION: Eight courses of pembrolizumab maintenance therapy were given as first-line treatment for squamous cell lung cancer; however, the patient was subsequently hospitalized due to a rapid increase in hepatobiliary enzymes. On endoscopic ultrasound, the common bile duct was dilated to 11 mm, and the wall, throughout its length from the papilla, was thickened. Endoscopic retrograde cholangiopancreatography showed no obvious stenosis in the lower bile duct; however, a parapapillary diverticulum was found, and papillary incision and bile duct plastic stent insertion were carried out. However, the liver disorder did not improve and overt jaundice appeared subsequently; therefore, an immune-related cholangitis was suspected, and prednisolone (PSL) 35 mg/day was introduced from day 59 of admission. Following PSL initiation, a decrease in serum bilirubin level was observed; however, significant decrease was not observed in alkaline phosphatase. Given the history of recurrent infectious cholangitis, magnetic resonance cholangiopancreatography was carried out on day 70 of admission. The intrahepatic bile duct showed stenosis and dilated findings, which was considered to be a factor for repeated infectious cholangitis. CONCLUSION: No previous case reports have described the changes and progression in bile duct images in immune-related adverse events. Therefore, this case is noteworthy for considering the progression of immune-related cholangitis.

Clinicopathological analysis of hepatic immune-related adverse events in comparison with autoimmune hepatitis and graft-versus host disease.

Immune checkpoint inhibitors (ICIs) targeting programmed cell death 1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) are widely used to treat advanced metastatic cancers. Neutralisation of PD-1 or CTLA-4 by ICIs results in immune-related adverse events (irAEs). The clinicopathological features of twelve patients with hepatic irAEs were evaluated and compared to those of ten patients with autoimmune hepatitis (AIH) or graft-versus-host disease (GVHD). No significant difference was seen in serum levels of transaminases, whereas serum levels of IgG and anti-nuclear antibody were higher in patients with AIH than in those with GVHD or hepatic irAEs. Inflammation was limited to the liver lobes in patients with GVHD or hepatic irAEs, whereas patients with AIH exhibited both portal and lobular inflammation. Immunohistochemical analyses revealed a predominant infiltration of CD8+ T cells and defective accumulation of regulatory T cells (Tregs) expressing forkhead box p3 (FOXP3) in the lobular areas of patients with hepatic irAEs and GVHD. In contrast, periportal lesions of patients with AIH were characterised by an infiltration of CD4+ T cells, CD8+ T cells, CD20+ B cells, and FOXP3+ Tregs. Overall, the activation of CD8+ T cells in the absence of activation of Tregs potentially underlies the immunopathogenesis of hepatic irAEs.