Clinicopathological study of surgically treated non-neoplastic diseases of the pancreas with special reference to autoimmune pancreatitis.

Purpose: After the popularization of serum immunoglobulin G4 (IgG4) measurement and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in our institute, surgical resection for non-neoplastic diseases of the pancreas became less common. Although the incidence of such false-positive cases was clarified in the 10-year period after the introduction of these measures (2009-2018), these data were not compared with the 30 years before 2009 (1979-2008). This study was performed to determine the percentage of autoimmune pancreatitis (AIP) that was included during the latter period and how the numbers of false-positive cases differed between the two periods.

Widespread and multifocal carcinomas in situ (CISs) through almost the entire pancreas: report of a case with preoperative cytological diagnosis.

Purpose: It is imperative for prognostic improvement of pancreatic cancer that we try to diagnose carcinoma in situ (CIS) of lesions, i.e., precursors of invasive ductal carcinomas (IDCs) at an early stage, because results of treatment of patients with IDCs themselves continue to be rather unsatisfactory.

Pancreatogram findings for carcinoma in situ (CIS) of the pancreas seen on endoscopic retrograde cholangiopancreatography and postoperative pancreatography of resected specimens: can CIS be diagnosed preoperatively?

Background/aims: From 1992 to 2003, 7 carcinomata in situ (CIS) were incidentally discovered during microscopical observation of resected materials for advanced carcinomas of peripancreatic organs, of which 4 had undergone endoscopic retrograde cholangiopancreatography (ERCP) or postoperative pancreatography of the resected specimen (POP). In addition, 7 of 79 invasive ductal carcinomata (IDC) of the pancreas were accompanied by CIS > or =2 cm long. A total of 11 patients were reviewed here for pancreatographic findings for CIS of the pancreas.

Image-diagnostic features of mature cystic teratomas of the pancreas: report on two cases difficult to diagnose preoperatively.

This report documents the findings of two rare cases of mature cystic teratoma of the pancreas. Although they could not be diagnosed preoperatively, our retrospective report suggests that the combined diagnosis of ultrasonography (US), enhanced computed tomography (CT), and magnetic resonance cholangiopancreatography (MRCP) might allow differentiation from other cystic lesions such as mucinous cystic tumors (MCTs) and intraductal papillary-mucinous tumors (IPMTs). Since the cystic teratomas were both filled with keratinous and sebaceous material, they were echogenic, appearing as solid masses on US.

Clinicopathology of pancreaticobiliary maljunction: relationship between alterations in background biliary epithelium and neoplastic development.

Background/purpose: Between 1988 and 2003, 38 patients underwent biliary resection for pancreaticobiliary maljunction (PBM). We reviewed the histopathologic findings for the surgically resected specimens to compare the clinical and pathologic features and assess the relationship between changes in the background biliary epithelium and the development of neoplasms.

Methods: Papillary hyperplasia (PHP) seen in the biliary epithelium of patients with PBM, was classified into grades 0--III in the gallbladder and grades 0--II in the extrahepatic bile duct, according to the extent, and was assessed for links with tumors in the same specimens.

Surgical treatment of intraductal papillary-mucinous tumor (IPMT) of the pancreas: operative indications based on surgico-pathologic study focusing on invasive carcinoma derived from IPMT.

Background/purpose: Between 1979 and 2000, 51 patients with intraductal papillary-mucinous tumor (IPMT) of the pancreas underwent surgical resection.

Methods: The patients were reviewed to disclose the surgical pathology of invasive carcinoma derived from IPMT and to determine the surgical indications for IPMT on the basis of the pathologic findings.

Results: The incidence of invasive carcinoma derived from IPMT according to the localization of the tumor was as follows: 4/9 (44%) in the main pancreatic duct (MPD type), 4/9 (44%) showing ductal spread from the MPD to branch ducts (mixed type), and 2/33 (6%) in the 2 branch duct (branch type).

The activation of caspase-3 and DNA fragmentation in B cells phagocytosed by macrophages.

Apoptotic signaling of mammalian cells involves two pathways: the death receptor and mitochondrial pathways. In this in vivo study, we investigated apoptotic signaling of B cells in mouse germinal centers (GCs) of gut-associated lymphoid tissues (GALTs) using transmission electron microscopy (TEM), terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labeling (TUNEL), immunofluorescence of members of caspase family and cFLIP(L), and caspase activity assay. It was very difficult to ultrastructurally differentiate B cells undergoing apoptosis from B cells differentiating into memory cells or plasma cells among B cells constituting GCs.