Diffuse pancreatic parenchymal atrophy, an imaging finding predictive of the development of pancreatic ductal adenocarcinoma: A case-control study.

Background and Aim: Pancreatic ductal adenocarcinoma (PDAC) is a lethal cancer, partly because its early detection is difficult. This study aimed to identify computed tomography (CT) findings associated with PDAC prior to diagnosis. Methods: Past CT images were retrospectively collected from the PDAC group (n = 54) and the control group (n = 90). The following imaging findings were compared: pancreatic mass, main pancreatic duct (MPD) dilatation with or without cutoff, cyst, chronic pancreatitis with calcification, partial parenchymal atrophy (PPA), and diffuse parenchymal atrophy (DPA). In the PDAC group, CT findings were examined during the pre-diagnostic period and 6-36 months and 36-60 months before diagnosis. Multivariate analyses were performed using logistic regression. Results: MPD dilatation with cutoff (P < 0.0001) and PPA (P = 0.023) were identified as significant imaging findings 6-36 months before diagnosis. DPA was identified as a novel imaging finding at 6-36 months (P = 0.003) and 36-60 months (P = 0.009) before diagnosis. Conclusion: DPA, MPD dilatation with cutoff, and PPA were identified as imaging findings associated with pre-diagnostic PDAC.

Direct peroral cholangioscopy with red dichromatic imaging 3 detected the perihilar margin of superficial papillary extension in a patient with intraductal papillary neoplasm of the bile duct.

Intraductal papillary neoplasms of the bile duct (IPNB) are a tumor derived from bile duct epithelium that tends to spread laterally and non-invasively. Surgery is the first-choice treatment for IPNB. It is extremely important to accurately diagnose the extent of lateral tumor extension. Although peroral cholangioscopy (POCS) is a potentially useful modality for detecting tumor range with direct observation, poor image quality is a limitation of POCS. Recently, a new-generation endoscopy system (EVIS X1) was equipped with functions such as red dichromatic imaging to improve image quality. A 75-year-old man with cholangitis was referred to our department. Various imaging studies showed a mass in the middle to lower bile duct and dilatation of the common bile duct and the intrahepatic bile duct. Endoscopic retrograde cholangiopancreatography was performed. A biopsy of the main tumor in the lower common bile duct revealed IPNB. It was difficult to determine the extent of superficial tumor extension with modalities such as contrast-enhanced computed tomography, magnetic resonance imaging, and endoscopic ultrasonography but the detailed evaluation was possible using POCS with red dichromatic imaging 3. The patient underwent hepatopancreatoduodenectomy. This case suggests the usefulness of direct observation using POCS with red dichromatic imaging 3 to determine the range of IPNB.

Self-expandable metal stents have longer patency and less cholangitis than inside stents in malignant perihilar biliary obstruction.

Background and Aim: Outcomes of an inside stent (IS, a plastic stent placed above the sphincter of Oddi) versusa self-expandable metal stent (SEMS) for the drainage of malignant perihilar biliary obstruction has not been fully studied. The drainage strategy for perihilar biliary obstruction is difficult and should be clarified. Methods: Clinical data of patients who underwent biliary drainage for malignant perihilar biliary obstruction with IS or SEMS between April 2016 and September 2021 at our institution were retrospectively examined. Outcomes, including the time to recurrent biliary obstruction (TRBO), survival, and incidence of recurrent biliary obstruction with concomitant cholangitis (RBOC), were retrospectively evaluated. Results: Median TRBO was 280 (95% confidence interval [CI], 110-not available) days in the SEMS group (n = 24) and 113 (95% CI, 74-192) days in the IS group (n = 25) (P = 0.043). Among the patients with perihilar cholangiocarcinoma, the median survival of the two groups was comparable, namely 330 days in the SEMS group and 359 days in the IS group (P = 0.46). The incidence of RBOC at re-intervention was significantly higher in patients with ISs (83.9%) than in those with SEMSs (0%) (P = 0.00004). Conclusions: TRBO was significantly longer in the SEMS group. Regardless of whether SEMSs or ISs were placed during the first intervention, patient survival was similar. Using easily removable ISs first might be a reasonable option because TRBO with SEMSs was shorter than patient survival. Cholangitis is a problem associated with the placement of IS.

Neutrophil Infiltration and Acinar-ductal Metaplasia Are the Main Pathological Findings in Pembrolizumab-induced Pancreatitis.

The histopathological findings of immune checkpoint inhibitor (ICI)-induced pancreatitis have rarely been reported. A 56-year-old man with squamous cell carcinoma of the lung with bone metastasis was being treated with pembrolizumab, an anti-programmed cell death protein-1 antibody. After 13 doses, he was referred to our department due to pancreatitis. Despite characteristic symptoms of acute pancreatitis, imaging findings were similar to those of autoimmune pancreatitis. However, a histological examination showed neutrophil-based inflammatory cell infiltration and acinar-ductal metaplasia. Immunostaining showed CD8-positive T lymphocyte infiltration. This case revealed the characteristic histopathology of pembrolizumab-induced pancreatitis, which was previously poorly understood.

Nasopancreatic Drainage for 4 Patients during the Early Phase of Acute Pancreatitis.

We encountered 4 patients with acute pancreatitis (AP) of various etiologies and coexisting acute cholangitis who underwent endoscopic biliary stenting (EBS) and nasopancreatic drainage (NPD) via endoscopic retrograde cholangiopancreatography (ERCP) during the early phase of AP. ERCP is performed to treat acute cholangitis even in the context of AP. However, in difficult cases, accidental contrast media injection or guidewire insertion into the pancreatic duct can happen during ERCP for the purpose of EBS. It is concerned that cannulation injury and increased pancreatic duct pressure can exacerbate existing AP. Because pancreatic guidewire-associated techniques were required for all of them due to difficult biliary cannulation, we performed a NPD catheter placement using the pancreatic guidewire to decompress the pancreatic duct to prevent further exacerbating AP. Surprisingly, all patients dramatically improved without systemic or local complications. NPD could be performed without any adverse events and did not worsen the course of AP. Early decompression of a pancreatic duct using NPD may rather improve AP that had already developed. Further prospective research is needed to confirm our observations.