No abstract

Intraductal papillary mucinous neoplasm (IPMN) is a common pancreatic cystic neoplasm that is often invasive and metastatic, resulting in a poor prognosis. Few molecular alterations unique to IPMN are known. We performed whole-exome sequencing for a primary IPMN tissue, which uncovered somatic mutations in KCNF1, DYNC1H1, PGCP, STAB1, PTPRM, PRPF8, RNASE3, SPHKAP, MLXIPL, VPS13C, PRCC, GNAS, KRAS, RBM10, RNF43, DOCK2, and CENPF. We further analyzed GNAS mutations in archival cases of 118 IPMNs and 32 pancreatic ductal adenocarcinomas (PDAs), which revealed that 48 (40.7%) of the 118 IPMNs but none of the 32 PDAs harbored GNAS mutations. G-protein alpha-subunit encoded by GNAS and its downstream targets, phosphorylated substrates of protein kinase A, were evidently expressed in IPMN; the latter was associated with neoplastic grade. These results indicate that GNAS mutations are common and specific for IPMN, and activation of G-protein signaling appears to play a pivotal role in IPMN.

In conclusion, the present study confirmed that cirrhotic NASH has a similar course to LC-C. The occurrence of HCC was the strongest predictor of mortality in the NASH groups. These findings may be helpful when deciding on therapeutic interventions for NASH and also for the daily management of these patients.

Several authors have reported a case of chronic pancreatitis associated with Sjögren's syndrome in which an autoimmune mechanism may have been involved in the etiology and in which steroid therapy was effective. We recently encountered a patient with pancreatitis who had hyperglobulinemia, was autoantibody-positive, and responded to steroid therapy. This patient, however, failed to show any evidence of association with Sjögren's syndrome or other collagen diseases. Although the concept of autoimmune hepatitis and the criteria for diagnosing it have been established, autoimmune pancreatitis has not yet been defined as a clinical entity. We report a case of chronic pancreatitis in which an autoimmune mechanism is involved in the etiology and summarize the cases of pancreatitis suspected of being caused by an autoimmune mechanism in the Japanese and English literature.

The present study confirmed that older age and advanced fibrosis were important risk factors for HCC, and that HCC was the major cause of mortality in NASH patients with advanced fibrosis. Regular screening for HCC is thus extremely important for NASH patients with advanced fibrosis.