https://www.selleckchem.com/products/bay-k-8644.html A 75-year-old woman was diagnosed with clinical stage III lung cancer. The patient was treated with chemoradiotherapy and subsequent durvalumab, an anti-PD-L1 antibody immune checkpoint inhibitor (ICI). Liver dysfunction was observed 14 days after the start of durvalumab therapy (aspartate transaminase, 218U/l;alanine aminotransferase, 169U/l). This corresponded to a grade 3 adverse event according to the Common Terminology Criteria for Adverse Events. The second course of durvalumab was withheld. The patient was hospitalized 31 days after durvalumab therapy because of worsening liver dysfunction. Laboratory findings and imaging examinations suggested liver injury due to an immune-related adverse event (irAE). Liver biopsy performed 38 days after durvalumab therapy showed severe lymphocyte and plasma cell infiltration into the portal tract, focal necrosis in the hepatic lobules, and necrotic changes around the hepatic lobules. These findings were similar to those of autoimmune hepatitis (AIH). Immunohistochemh steroids. Thus, high-dose steroids diminishing the therapeutic effect of ICIs is a concern, and it is important to control irAEs with low-dose steroids that are started earlier.A woman in her 50s was referred due to a solid mass in the head of the pancreas. It was diagnosed as a neuroendocrine carcinoma (NEC) by endoscopic ultrasound-guided fine-needle aspiration. Consequently, pancreatoduodenectomy was performed. A well-differentiated adenocarcinoma component was revealed in the resected bile duct, suggesting a relationship with the NEC component in the pancreas. Genetic examination suggested that cholangiocarcinoma, but not coexisting carcinoma, was converted to NEC after the interstitial invasion. Finally, it was diagnosed as the NEC derived from the extrahepatic bile duct, which is rare at about 0.2-2% in gastrointestinal neuroendocrine neoplasms.A 44-year-old man was admitted because of general malaise,