Published papers

Objectives Some intraductal papillary mucinous neoplasms (IPMNs) have malignant potential and can become pancreatic cancer. The mechanism behind the malignant progression of IPMN remains unknown. We aimed to identify the risk factors and interactions between backgrounds for IPMN. Methods We retrospectively enrolled 980 patients of pancreatic cancer or suspected IPMN (sIPMN) who underwent endoscopic ultrasound or retrograde cholangiopancreatography. We classified them into pancreatic cancer, high-risk sIPMN, and low-risk sIPMN, and investigated the risk factors for high-risk sIPMN. Results Smoking habits (odds ratio [OR], 3.74; 95% confidence interval [CI], 2.04-6.85; P < 0.001), serum carbohydrate antigen 19-9 ≥37 U/mL (OR, 6.30; 95% CI, 2.88-13.80; P < 0.001), and family history of cancers (OR, 2.38; 95% CI, 1.30-4.37; P = 0.005) were independent risk factors for high-risk suspected IPMN. Odds ratios of diabetes and neutrophil-to-lymphocyte ratio of 2.45 or greater were significantly higher in patients with a family history of cancer than those without a family history of cancer (OR, 3.28; 95% CI, 0.52-20.80 vs 1.85; 95% CI, 0.78-4.41; OR, 2.44; 95% CI, 0.81-7.34 vs 1.24; 95% CI, 0.67-2.30, respectively). Conclusions Understanding the interactions between background factors can effectively prevent IPMNs' malignant transformation.

Introduction and importance: A central hepatic bisectionectomy (CHBS) for a hilar cholangiocarcinoma (CCA) is technically challenging because bilateral biliary reconstruction is required after resection. On the other hand, hepatic artery resection and reconstruction in a major liver resection are also technical procedures. In this report, we describe our radical CHBS with hepatic artery and biliary tracts reconstruction for a patient with nodular type intrahepatic hilar CCA. Case presentation: A 76-year-old man was referred for further investigation of an incidental hepatic tumor. The hepatic tumor was located from medial sector to anterior sector with encasement of the anterior branch of the right hepatic artery. Based on these findings, we performed a CHBS with right hepatic artery and biliary tracts reconstruction. The histopathological findings revealed that the tumor consisted of moderately differentiated tubular adenocarcinoma with tumor necrosis without a fibrous capsule. In this area, tumors cells had invaded branches of the hepatic vein; however, there was no destructive invasion to the hepatic artery. Consequently, he was diagnosed with a nodular type intrahepatic hilar CCA with pT2aN0M0. Clinical discussion: A CHBS is usually performed with the intent of anatomically preserving a patient's liver as much as possible. Concomitant resection and reconstruction of the hilar vessels and biliary tracts with CHBS is one of the most technically challenging procedures in liver resections. Conclusion: A CHBS with hepatic artery and biliary reconstruction may be a promising alternative if expert surgeons perform it on strictly selected patients.

How to optimize perioperative factor VIII (FVIII) replacement through hemostatic monitoring is critically important to manage hemophilia A patients. The bispecific antibody emicizumab binds activated FIX (FIXa) and FX to functionally mimic FVIIIa. While being used for hemostatic control in hemophilia A, this therapeutic antibody inconveniently interferes with coagulation tests using human FIXa and FX, such as activated partial thromboplastin time (APTT) and FVIII activity measurement based on one-stage clotting assays. Clot waveform analysis (CWA) extends the interpretation of measurement curves for coagulation time to provide global information. We performed APTT-CWA to monitor perioperative hemostasis in a hemophilia A patient on emicizumab undergoing liver transplantation. Plasma samples were treated with anti-idiotype monoclonal antibodies against emicizumab to enable accurate coagulation assays. Kinetics of maximum coagulation velocity and acceleration mimicked that of FVIII activity. These CWA parameters better correlated with FVIII activity than APTT. The plateaus of them were observed at FVIII activity of 100% or more, supporting the protocol for perioperative FVIII replacement. Thus, CWA may measure coagulation potential in hemophilia A patients undergoing liver transplantation, aiding in optimizing perioperative hemostasis.

Cell transplantation using mesenchymal stem cells (MSCs) has emerged as a promising approach to repairing and regenerating injured or impaired organs. However, the survival and retention of MSCs following transplantation remain a challenge. Therefore, we investigated the efficacy of co-transplantation of MSCs and decellularized extracellular matrix (dECM) hydrogels, which have high cytocompatibility and biocompatibility. The dECM solution was prepared by enzymatic digestion of an acellular porcine liver scaffold. It could be gelled and formed into porous fibrillar microstructures at physiological temperatures. MSCs expanded three-dimensionally in the hydrogel without cell death. Compared to the 2-dimensional cell culture, MSCs cultured in the hydrogel showed increased secretion of hepatocyte growth factor (HGF) and tumor necrosis factor-inducible gene 6 protein (TSG-6), both of which are major anti-inflammatory and anti-fibrotic paracrine factors of MSCs, under TNFα stimulation. In vivo experiments showed that the co-transplantation of MSCs with dECM hydrogel improved the survival rate of engrafted cells compared to those administered without the hydrogel. MSCs also demonstrated therapeutic effects in improving inflammation and fibrosis of pancreatic tissue in a dibutyltin dichloride (DBTC)-induced rat pancreatitis model. Combinational use of dECM hydrogel with MSCs is a new strategy to overcome the challenges of cell therapy using MSCs and can be used for treating chronic inflammatory diseases in clinical settings.