Recent advancements in image-enhanced endoscopy in the pancreatobiliary field.

Image-enhanced endoscopy (IEE) has advanced gastrointestinal disease diagnosis and treatment. Traditional white-light imaging has limitations in detecting all gastrointestinal diseases, prompting the development of IEE. In this review, we explore the utility of IEE, including texture and color enhancement imaging and red dichromatic imaging, in pancreatobiliary (PB) diseases. IEE includes methods such as chromoendoscopy, optical-digital, and digital methods. Chromoendoscopy, using dyes such as indigo carmine, aids in delineating lesions and structures, including pancreato-/cholangio-jejunal anastomoses. Optical-digital methods such as narrow-band imaging enhance mucosal details and vessel patterns, aiding in ampullary tumor evaluation and peroral cholangioscopy. Moreover, red dichromatic imaging with its specific color allocation, improves the visibility of thick blood vessels in deeper tissues and enhances bleeding points with different colors and see-through effects, proving beneficial in managing bleeding complications post-endoscopic sphincterotomy. Color enhancement imaging, a novel digital method, enhances tissue texture, brightness, and color, improving visualization of PB structures, such as PB orifices, anastomotic sites, ampullary tumors, and intraductal PB lesions. Advancements in IEE hold substantial potential in improving the accuracy of PB disease diagnosis and treatment. These innovative techniques offer advantages paving the way for enhanced clinical management of PB diseases. Further research is warranted to establish their standard clinical utility and explore new frontiers in PB disease management.

Reconsidering resectable oncological conditions in pancreatic tail cancer: A multicenter retrospective study on prognostic factors in pancreatic tail cancer after resection (HOPS Pt-01).

BACKGROUND: Pancreatic tail cancer (Pt-PC) is generally considered resectable when metastasis is absent, but doubts persist in clinical practice due to the variability in local tumor extent. We conducted a multicenter retrospective study to comprehensively identify prognostic factors associated with Pt-PC after resection. METHODS: We enrolled 100 patients that underwent distal pancreatectomy. The optimal combination of factors influencing relapse-free survival (RFS) was determined using the maximum likelihood method (MLM) and corrected Akaike and Bayesian information criteria (AICc and BIC). Prognostic elements were then validated to predict oncological outcomes. RESULTS: Therapeutic interventions included neoadjuvant treatment in 16 patients and concomitant visceral resection (CVR) in 37 patients; 89 patients achieved R0. Median RFS and OS after surgery were 23.1 and 37.1 months, respectively. AICc/BIC were minimized in the model with ASA-PS (≥2), CA19-9 (≥112 U/mL at baseline, non-normalized postoperatively), need for CVR, 6 pathological items (tumor diameter ≥19.5 mm, histology G1, invasion of the anterior pancreatic border, splenic vein invasion, splenic artery invasion, lymph node metastasis), and completed adjuvant treatment (cAT) for RFS. Regarding the predictive value of these 11 factors, area under the curve was 0.842 for 5-year RFS. Multivariate analysis of these 11 factors showed that predictors of RFS include CVR (hazard ratio, 2.13; 95 % confidence interval, 1.08-4.19; p = 0.028) and cAT (0.38, 0.19-0.76; p = 0.006). CONCLUSIONS: The MLM identified certain Pt-PC cases warranting consideration beyond resectable during clinical management. Particular attention should be paid to conditions requiring CVR, even though immortal time bias remains unresolved with adjuvant treatment.

Tip-in endoscopic papillectomy for ampullary adenoma near diverticulum to minimize complications.

Toyonaga and colleagues present a novel "tip-in endoscopic papillectomy" approach for resecting ampullary tumors, aiming to minimize complications like perforation and residual tumor by adapting the colonic polyp endoscopic mucosal resection tip-in method. The technique is described with accompanying video in a case of ampullary tumor near a diverticulum.

The application of low echo reduction in endoscopic ultrasound-guided tissue acquisition for pancreatic mass lesions.

Toyonaga and colleagues demonstrate, with accompanying video, the use of low echo reduction, which is a novel endoscopic ultrasound function provided by a new endoscopic ultrasound processor that increases contrast without white-out. Low echo reduction might be useful in improving lesion boundaries and needle visibility during endoscopic ultrasound-guided tissue acquisition.

Tumor-Informed Approach Improved ctDNA Detection Rate in Resected Pancreatic Cancer.

Pancreatic cancer is one of the cancers with very poor prognosis; there is an urgent need to identify novel biomarkers to improve its clinical outcomes. Circulating tumor DNA (ctDNA) from liquid biopsy has arisen as a promising biomarker for cancer detection and surveillance. However, it is known that the ctDNA detection rate in resected pancreatic cancer is low compared with other types of cancer. In this study, we collected paired tumor and plasma samples from 145 pancreatic cancer patients. Plasma samples were collected from 71 patients of treatment-naïve status and from 74 patients after neoadjuvant therapy (NAT). Genomic profiling of tumor DNA and plasma samples was conducted using targeted next-generation sequencing (NGS). Somatic mutations were detected in 85% (123/145) of tumors. ctDNA was detected in 39% (28/71) and 31% (23/74) of treatment-naïve and after-NAT groups, respectively, without referring to the information of tumor profiles. With a tumor-informed approach (TIA), ctDNA detection rate improved to 56% (40/71) and 36% (27/74) in treatment-naïve and after-NAT groups, respectively, with the detection rate significantly improved (p = 0.0165) among the treatment-naïve group compared to the after-NAT group. Cases who had detectable plasma ctDNA concordant to the corresponding tumor showed significantly shorter recurrence-free survival (RFS) (p = 0.0010). We demonstrated that TIA improves ctDNA detection rate in pancreatic cancer, and that ctDNA could be a potential prognostic biomarker for recurrence risk prediction.

HOPS-R01 phase II trial evaluating neoadjuvant S-1 therapy for resectable pancreatic adenocarcinoma.

Although neoadjuvant therapy (Nac) is recommended for high-risk resectable pancreatic cancer (R-PDAC), evidence regarding specific regimes is scarce. This report aimed to investigate the efficacy of S-1 Nac for R-PDAC. In a multicenter phase II trial, we investigated the efficacy of Nac S-1 (an oral fluoropyrimidine agent containing tegafur, gimeracil, and oteracil potassium) in R-PDAC patients. The protocol involved two cycles of preoperative S-1 chemotherapy, followed by surgery, and four cycles of postoperative S-1 chemotherapy. Two-year progression-free survival (PFS) rates were the primary endpoint. Overall survival (OS) rates and median survival time (MST) were secondary endpoints. Forty-nine patients were eligible, and 31 patients underwent resection following Nac, as per protocol (31/49; 63.3%). Per-protocol analysis included data from 31 patients, yielding the 2-year PFS rate of 58.1%, and 2-, 3-, and 5-year OS rates of 96.8%, 54.8%, and 44.0%, respectively. MST was 49.2 months. Intention-to-treat analysis involved 49 patients, yielding the 2-year PFS rate of 40.8%, and the 2-, 3-, and 5-year OS rates of 87.8%, 46.9%, and 33.9%, respectively. MST was 35.5 months. S-1 single regimen might be an option for Nac in R-PDAC; however, the high drop-out rate (36.7%) was a limitation of this study.

Synergistic effect of IFN-γ and IL-1ß on PD-L1 expression in hepatocellular carcinoma.

Immunotherapy using anti-programmed death 1 ligand 1 (PD-L1) antibodies has shown clinical efficacy against hepatocellular carcinoma (HCC) and is recognized as the first-line treatment for unresectable HCC. PD-L1 expression is affected by various cytokines produced by immune cells in the tumor microenvironment; however, there is limited information about the effects of cytokine interactions on PD-L1 expression. In this study, we examined how cytokines induce PD-L1 expression in HCC cells. Both interferon gamma (IFN-γ) and interleukin 1 beta (IL-1ß) induced PD-L1 expression, and the two cytokines enhanced PD-L1 expression in combination compared to that when administered alone. The Janus kinase/signal transducer and activator of transcription signaling pathway activated by IFN-γ is the major pathway of PD-L1 expression. The increase in interferon regulatory factor 1 expression and IFN-γ receptor expression induced by IL-1ß was associated with the synergistic effect of IFN-γ and IL-1ß on PD-L1 expression. These findings strongly indicate that IFN-γ and IL-1ß affect the mechanism underlying immune resistance in HCC cells.

Sustained Eosinophilic Cholangitis Due to a Mite Allergy Mimicking Sclerosing Cholangitis.

Eosinophilic cholangiopathy (EC) presents with thickening and stenosis of the bile duct wall that is histologically characterized by eosinophil infiltration. The diagnosis is often difficult. We herein report a patient who had been followed up with a diagnosis of primary sclerosing cholangitis but had a final diagnosis of EC based on eosinophilia, histological findings of bile duct and liver biopsy specimens, and a review of a previous surgical specimen of the gallbladder. Antigen tests, isolation from her house, and accidental re-exposure to the antigen revealed that the causative antigen was the mite Dermatophagoides pteronyssinus.

Concordance of the histological diagnosis of type 1 autoimmune pancreatitis and its distinction from pancreatic ductal adenocarcinoma with endoscopic ultrasound-guided fine needle biopsy specimens: an interobserver agreement study.

The histological diagnosis of type 1 autoimmune pancreatitis (AIP) based on the findings obtained by an endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) is feasible, but the diagnostic consistency of this method has not been confirmed. We determined the interobserver agreement among 20 pathologists regarding the diagnosis of type 1 AIP, including the distinction from pancreatic ductal adenocarcinoma (PDAC) using large tissue samples obtained by EUS-FNB. After guidance for diagnosing AIP with biopsy tissues was provided, a round 2 was performed. The median sensitivity and specificity for diagnosing PDAC vs. non-neoplastic diseases were 95.2% and 100%, respectively. In groups of specialists (n = 7) and the generalists (n = 13), Fleiss' к-values increased from 0.886 to 0.958 and from 0.750 to 0.816 in round 2. The concordance was fair or moderate for obliterative phlebitis and storiform fibrosis but slight for ductal lesion of type 1 AIP. Discordant results were due to ambiguous findings and biopsy tissue limitations. Among the specialists, the ratio of cases with perfect agreement regarding the presence of storiform fibrosis increased in round 2, but agreement regarding obliterative phlebitis or ductal lesions was not improved. Although the histological definite diagnosis of type 1 AIP was achieved by most observers in > 60% of the cases, the confidence levels varied. Because some ambiguities exist, the histological diagnostic levels based on the diagnostic criteria of type 1 AIP should not be taken for granted. Guidance is effective for improving accurate PDAC diagnoses (notably by recognizing acinar-ductal metaplasia) and for evaluating storiform fibrosis.

Mixed neuroendocrine non-neuroendocrine neoplasm of the gallbladder complicated by a pancreaticobiliary maljunction of a non-dilated biliary duct: A case report.

RATIONALE: Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is a rare tumor. MiNEN of the gallbladder (GB) with pancreaticobiliary maljunction (PMJ) is extremely rare. The origin of MiNEN of the GB remains unknown; the biliary tract normally lacks neuroendocrine cells. MiNEN of the GB has a poor prognosis; because of its rarity, no treatment or management guidelines have been established yet. PATIENT CONCERNS: A 47-year-old male presenting with right hypochondrial pain and malaise for 3 months was referred to our hospital for further management. DIAGNOSIS: The neuron-specific enolase level was increased. Contrast-enhanced computed tomography revealed a mass of 70 mm in size with unclear boundaries in the liver. The GB was surrounded by this mass, narrowing the lumen of the GB. Many swollen lymph nodes were observed in the hepatoduodenal ligament. Endoscopic retrograde cholangiopancreatography revealed a PMJ with a non-dilated biliary duct. A percutaneous biopsy was performed on the liver mass, and the pathological findings were neuroendocrine carcinoma (NEC) (small cell type). We diagnosed a NEC of the GB, T3N1M0, stage IIIB (Union for International Cancer Control, 7th edition). INTERVENTIONS: Because of advanced lymph node metastasis, we considered this tumor difficult to cure solely by surgical intervention. After initial chemotherapy consisting of cisplatin and irinotecan, a marked reduction in both tumor and lymph node sizes enabled conversion surgery. The pathological diagnosis of the resected tumor was MiNEN consisting of NEC and adenocarcinoma. The primary lesion was the adenocarcinoma occupying the luminal side of the GB. As a postsurgical treatment, the patient received additional irradiation therapy to the common hepatic duct and liver stump because of positive surgical margins. OUTCOMES: At 13 months postoperatively, computed tomography findings revealed the appearance of a hypervascular liver tumor, and laboratory data showed increased serum neuron-specific enolase levels. Chemotherapy was unsuccessful, leading to the death of the patient 36 months from the date of diagnosis. LESSONS: There are several reports on the development of MiNEN of the GB. In our case, a PMJ-related adenocarcinoma of the GB transdifferentiated into NEC. Further accumulation of cases is necessary to establish a treatment strategy for MiNEN of the GB.

Amplification of mutant KRASG12D in a patient with advanced metastatic pancreatic adenocarcinoma detected by liquid biopsy: A case report.

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest cancer types. Activating oncogenic KRAS mutations are commonly observed in PDAC; however, oncogenic KRAS amplification is rarely observed, and its significance in prognosis and resistance to therapy remains poorly characterized. The present report describes the case of a 52-year-old male patient diagnosed with advanced PDAC with liver metastasis. The patient received modified FOLFIRINOX (mFFX) therapy to which the patient became intolerant with a strong inflammatory response. Subsequent treatment with gemcitabine plus nab-paclitaxel failed to control the disease. Targeted genetic analysis revealed KRAS G12D and TP53 R248Q mutations in the primary tumor and liver metastases. Analysis of circulating tumor DNA (ctDNA) before the first line of treatment confirmed these genetic findings and revealed a >4-fold amplification of the mutant KRAS G12D not detected in the primary tumor. Additionally, subsequent analysis confirmed a 5-fold amplification of the KRAS G12D allele in liver metastasis. Consecutive monitoring of ctDNA revealed an initial decrease in the tumor burden 2 weeks after the first cycle of mFFX. However, coinciding with treatment intolerance, a sharp increase in tumor mutational levels and KRAS G12D amplification was observed 1 month later. The patient died 70 days after treatment initiation. Overall, amplification of oncogenic KRAS G12D was not only associated with an aggressive phenotype, but also supported cancer resistance to chemotherapy. Importantly, this case suggests that plasma detection of KRAS G12D amplification is feasible in the clinical routine and constitutes a powerful tool for assessing tumor aggressiveness.