Diagnosis of pancreatic malignancies using an overnight-stored pancreatic juice cell block specimen.

BACKGROUND AND AIMS: Pancreatic juice cytology is useful for diagnosing pancreatic duct strictures and cystic lesions. However, some cases cannot be diagnosed using cytology. This study aimed to evaluate the utility of the overnight-stored pancreatic juice cell block (CB) method for diagnosing pancreatic disease. METHODS: This retrospective study included 32 patients who presented with pancreatic duct strictures or cystic lesions between 2018 and 2024. The sensitivity, specificity, and accuracy of the CB method and single/multiple pancreatic juice cytology were compared to evaluate the utility of the CB. RESULT: An endoscopic nasopancreatic drainage tube was placed in the main pancreatic duct, and pancreatic juice was collected to create a CB specimen. The median amount of pancreatic juice collected was 180(30-200) mL, and the median number of cytological examinations was three(2-8). Of the 32 cases, 13 were malignant, and 19 were benign (non-malignant). The sensitivity was significantly higher for the CB method (62 %) than for single cytology(15 %, P = 0.0414), and there was no significant difference between CB and multiple cytology(54 %, P = 1.0). The specificity and accuracy were not significantly different between the CB method and single or multiple cytology. When multiple cytology and CB were combined, sensitivity improved to 77 %. The pathological findings of the CB specimens were similar to the surgical specimens, including immunohistochemistry. CONCLUSION: The overnight-stored pancreatic juice CB method was more effective than single cytology, with similar sensitivities to multiple cytology and can also be used for immunohistochemistry. The pancreatic juice CB method is useful for pancreatic juice assessment.

Pancreatic juice cytology for diagnosing invasive pancreatic carcinoma/high-grade pancreatic intraepithelial neoplasia without visible tumors on endoscopic ultrasound.

OBJECTIVES: Pancreatic ductal adenocarcinoma (PDAC) with a diameter ≤10 mm and high-grade pancreatic intraepithelial neoplasia (HG-PanIN) require pre-operative diagnosis. Most cases present only indirect imaging findings without visible tumors on endoscopic ultrasound (EUS). Therefore, EUS-guided fine-needle aspiration/biopsy is not applicable. An alternative diagnostic method is pancreatic juice cytology (PJC) via endoscopic naso-pancreatic drainage (ENPD-PJC), which is not the standard practice. This study aimed to investigate ENPD-PJC for diagnosing suspected PDAC/HG-PanIN cases without visible tumors on EUS. METHODS: Data of patients with suspected PDAC/HG-PanIN without visible tumors who underwent PJC were retrospectively evaluated. One PJC sample was collected during endoscopic retrograde pancreatography (ERP-PJC), and 12 samples were collected during ENPD-PJC, 3-hourly for cytological analysis. ERP-PJC, ERP/ENPD-PJC, and ENPD-PJC positivity indicated cytologically positive samples. Patients with positive/negative PJC with follow-up for <4-years were excluded as undiagnosed cases. A non-malignant diagnosis was based on histopathological absence/stable imaging findings for ≥4-years. The primary endpoint was to demonstrate that ERP/ENPD-PJC has a higher diagnostic ability than ERP-PJC. RESULTS: Twenty-two patients with histopathologically diagnosed PDAC/HG-PanIN and 31 with a non-malignant diagnosis were enrolled. ERP-PJC, ERP/ENPD-PJC, and ENPD-PJC showed sensitivities of 36.4 %, 86.4 %, and 77.3 %, specificities of 93.5 %, 87.1 %, and 93.5 %, and accuracies of 69.8 %, 86.7 %, and 86.7 %, respectively. ERP/ENPD-PJC and ENPD-PJC demonstrated superior sensitivity and accuracy compared to ERP-PJC. A greater occurrence of positive outcomes markedly distinguished true positives from false positives. CONCLUSIONS: ERP/ENPD-PJC and ENPD-PJC had higher diagnostic accuracies for PDAC/HG-PanIN without visible tumors on EUS. ENPD-PJC is recommended for the diagnosis of these lesions.

Simultaneous and sequential combination of genetic and epigenetic biomarkers for the presence of high-grade dysplasia in patients with pancreatic cyst: Discovery in cyst fluid and test in pancreatic juice.

BACKGROUND/OBJECTIVES: Screening patients with intraductal papillary mucinous neoplasms (IPMN) has the primary goal of identifying potentially curable noninvasive precursors. We aimed to evaluate the diagnostic impact of genetic and epigenetic biomarkers in the presence of noninvasive precursors. METHODS: Mutated KRAS/GNAS and methylated SOX17/TBX15/BMP3/TFPI2 DNA were assessed by droplet digital PCR in a discovery cohort of 70 surgically aspirated cyst fluids, and diagnostic performances for differentiating high-grade dysplasia (HGD) from low-grade dysplasia (LGD) was evaluated. We then tested these markers using an independent test cohort consisting of 156 serially collected pancreatic juice samples from 30 patients with IPMN. RESULTS: Mutated KRAS and GNAS are specific for IPMNs but are not helpful for the prediction of histological grades. Cyst fluids from IPMN with HGD showed higher methylation levels of SOX17 (median, 0.141 vs. 0.021; P = 0.086) and TBX15 (median, 0.030 vs. 0.003; P = 0.028) than those with LGD. The combination of all tested markers yielded a diagnostic performance with sensitivity of 69.6%, and specificity of 90.0%. Among the 30 pancreatic juice samples exhibiting the highest abundance of KRAS/GNAS mutations in each patient in the test cohort, patients with histologically proven HGD due to pancreatic resection had a significantly higher prevalence (100% vs. 31%, P = 0.018) and abundance (P = 0.037) of methylated TBX15 than those without cytohistological diagnosis undergoing surveillance. CONCLUSIONS: A simultaneous and sequential combination of mutated and methylated DNA markers in pancreatic cyst fluid and juice sample markers can help detect noninvasive pancreatic precursor neoplasms.

Pancreatic duct epithelial malignancy suggested by large focal pancreatic parenchymal atrophy in cystic diseases of the pancreas.

BACKGROUND: /Objectives: A cystic lesion is common in the pancreas. Focal pancreatic parenchymal atrophy (FPPA) has been reported as a sign of high-grade pancreatic intraepithelial neoplasia/carcinoma in situ (HGP/CIS). Some cystic lesions accompany FPPA. However, the relationship between a cystic lesion, FPPA, and the histopathological background of the pancreatic duct is unknown. METHODS: We retrospectively evaluated the data of 98 patients with a cystic lesion who underwent serial pancreatic juice aspiration cytologic examination (SPACE) because of accompanying FPPA, increased size of the cystic lesion, and pancreatic duct stricture at the base. RESULTS: The clinical diagnosis of a cystic lesion was intraductal papillary mucinous neoplasia (IPMN) and cysts in 72 (73.5%) and 26 (26.5%) patients, respectively. Ninety of the 98 patients (91.8%) had FPPA. Positive results (adenocarcinoma and suspicion) on SPACE were observed in 56 of all cases (57.1%), 48 of IPMN (66.7%), 8 of cysts (30.8%), and 54 of FPPA (59.3%), and were significantly associated with IPMN (p = 0.002) and the large FPPA (>269.79 mm2,p = 0.0001); moreover, these disorders are considerably related (p = 0.0003). Fifty patients (51.0%) with positive results on SPACE underwent surgery, with the histopathological diagnosis of epithelial malignancy in 42 patients (42.9%, 42/50, 84%). Many cystic lesions clinically diagnosed as IPMN were dilated branches covered by pancreatic intraepithelial neoplasia. CONCLUSIONS: Positive results on SPACE were significantly associated with the clinical diagnosis of IPMN and the large FPPA. Moreover, these disorders are significantly related. Surgery owing to positive results could lead to the histopathological diagnosis of HGP/CIS.

Mutation Analysis of Pancreatic Juice and Plasma for the Detection of Pancreatic Cancer.

Molecular profiling may enable earlier detection of pancreatic cancer (PC) in high-risk individuals undergoing surveillance and allow for personalization of treatment. We hypothesized that the detection rate of DNA mutations is higher in pancreatic juice (PJ) than in plasma due to its closer contact with the pancreatic ductal system, from which pancreatic cancer cells originate, and higher overall cell-free DNA (cfDNA) concentrations. In this study, we included patients with pathology-proven PC or intraductal papillary mucinous neoplasm (IPMN) with high-grade dysplasia (HGD) from two prospective clinical trials (KRASPanc and PACYFIC) for whom both PJ and plasma were available. We performed next-generation sequencing on PJ, plasma, and tissue samples and described the presence (and concordance) of mutations in these biomaterials. This study included 26 patients (25 PC and 1 IPMN with HGD), of which 7 were women (27%), with a median age of 71 years (IQR 12) and a median BMI of 23 kg/m2 (IQR 4). Ten patients with PC (40%) were (borderline) resectable at baseline. Tissue was available from six patients (resection n = 5, biopsy n = 1). A median volume of 2.9 mL plasma (IQR 1.0 mL) and 0.7 mL PJ (IQR 0.1 mL, p < 0.001) was used for DNA isolation. PJ had a higher median cfDNA concentration (2.6 ng/µL (IQR 4.2)) than plasma (0.29 ng/µL (IQR 0.40)). A total of 41 unique somatic mutations were detected: 24 mutations in plasma (2 KRAS, 15 TP53, 2 SMAD4, 3 CDKN2A 1 CTNNB1, and 1 PIK3CA), 19 in PJ (3 KRAS, 15 TP53, and 1 SMAD4), and 8 in tissue (2 KRAS, 2 CDKN2A, and 4 TP53). The mutation detection rate (and the concordance with tissue) did not differ between plasma and PJ. In conclusion, while the concentration of cfDNA was indeed higher in PJ than in plasma, the mutation detection rate was not different. A few cancer-associated genetic variants were detected in both biomaterials. Further research is needed to increase the detection rate and assess the performance and suitability of plasma and PJ for PC (early) detection.

Alterations in the pH of pancreatic juice are associated with chymotrypsin C inactivation and lithostathine precipitation in chronic pancreatitis patients: a proteomic approach.

BACKGROUND: The progression of chronic pancreatitis (CP), an inflammatory disease of the pancreas, causes pancreatic stones to form within the pancreatic ductal lumen/parenchyma, which occurs via protein plug formation. Pain is the most common symptom that necessitates clinical attention, and pain relief is the therapeutic goal for these patients. Endoscopic therapy and surgery are complimentary forms of therapy for pain relief. This study was envisaged to clarify the mechanism by which protein plug/soft stones form in pancreatic ducts prior to undergoing calcification. METHODS: Protein plugs were obtained from twenty CP patients undergoing therapeutic ERCP for stone removal. Pancreatic juice was obtained from five CP patients without stones. Proteins were isolated by TCA/acetone precipitation, SDS PAGE and 2-D gel electrophoresis to determine the protein profile. Protein spots from the 2-D gel were excised and subjected to matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) for identification. The effect of altered pH and elevated concentrations of trypsin on pancreatic juice protein was assessed by SDS‒PAGE to determine the protein profile. Differentially expressed protein bands were excised and subjected to MALDI-TOF. In silico analysis was performed by docking lithostathine with the calcite molecule using AutoDock Vina and PyMOL to clarify their interaction during stone formation. RESULTS: Twenty-three and twenty-nine spots from 2D gels of protein plugs and pancreatic juice, respectively, revealed that lithostathine (Reg1A) was the only protein in the protein plugs, whereas digestive enzymes and lithostathine were identified in pancreatic juice. Altered pH levels and increased trypsin concentrations in the pancreatic juice caused a protein to degrade via an unknown mechanism, and this protein was identified as chymotrypsin C (CTRC) by MALDI-TOF. Docking studies showed that the binding affinity of calcite was higher with the cleaved lithostathine, explaining the deposition of calcium that was observed around the protein plugs after calcified stones were formed through precipitation. CONCLUSION: Our results suggest that chymotrypsin C (CTRC) is degraded in an acidic environment, leading to the precipitation of lithostathine in the ductal lumen.

Extracellular vesicle-derived microRNAs in pancreatic juice as biomarkers for detection of pancreatic ductal adenocarcinoma.

INTRODUCTION: Pancreatic ductal adenocarcinoma (PDAC) is usually diagnosed in an advanced stage, with minimal likelihood of long-term survival. Only a small subset of patients are diagnosed with early (T1) disease. Early detection is challenging due to the late onset of symptoms and limited visibility of sub-centimeter cancers on imaging. A novel approach is to support the clinical diagnosis with molecular markers. MicroRNA derived from extracellular vehicles (EVs) in blood has shown promise as a potential biomarker for pancreatic neoplasia, but microRNA derived from pancreatic juice (PJ) may be a more sensitive biomarker, given that is in close contact with ductal cells from which PDAC arises. This study aims to evaluate and compare the performance of PJ- and serum-derived EV-miRNA for the detection of PDAC. METHODS: PJ was collected from the duodenum during EUS after secretin stimulation from 54 patients with PDAC and 118 non-malignant controls. Serum was available for a subset of these individuals. MiR-16, miR-21, miR-25, miR-155 and miR-210 derived from EVs isolated from PJ and serum were analyzed by qPCR, and serum CA19-9 levels were determined by electrochemiluminescence immunoassay. For statistical analysis, either a Mann-Whitney U test or a Wilcoxon Signed Rank test was performed. ROC curves and AUC were used to assess the sensitivity and specificity of miR expression for PDAC detection. RESULTS: Expression of EV-miR-21, EV-miR-25 and EV-miR-16 were increased in cases vs controls in PJ, while only EV-miR-210 was increased in serum. The potential to detect PC was good for a combination of PJ EV-miR-21, EV-miR-25, EV-miR-16 and serum miR-210, CA-19-9, with an area under the curve of 0.91, a specificity of 84.2% and a sensitivity of 81.5%. CONCLUSION: Detection of miRNA from EVs in PJ is feasible. A combined panel of PJ EV-miR-21, EV-miR-25, EV-miR-16, and serum EV-miR-210 and CA19-9 distinguishes cases with PDAC from controls undergoing surveillance with a specificity of 81.5% and sensitivity of 84.2%.

Systematic review and meta-analysis: Diagnostic performance of DNA alterations in pancreatic juice for the detection of pancreatic cancer.

BACKGROUND AND AIMS: Pancreatic cancer has a dismal prognosis. So far, imaging has been proven incapable of establishing an early enough diagnosis. Thus, biomarkers are urgently needed for early detection and improved survival. Our aim was to evaluate the pooled diagnostic performance of DNA alterations in pancreatic juice. METHODS: A systematic literature search was performed in EMBASE, MEDLINE Ovid, Cochrane CENTRAL and Web of Science for studies concerning the diagnostic performance of DNA alterations in pancreatic juice to differentiate patients with high-grade dysplasia or pancreatic cancer from controls. Study quality was assessed using QUADAS-2. The pooled prevalence, sensitivity, specificity and diagnostic odds ratio were calculated. RESULTS: Studies mostly concerned cell-free DNA mutations (32 studies: 939 cases, 1678 controls) and methylation patterns (14 studies: 579 cases, 467 controls). KRAS, TP53, CDKN2A, GNAS and SMAD4 mutations were evaluated most. Of these, TP53 had the highest diagnostic performance with a pooled sensitivity of 42% (95% CI: 31-54%), specificity of 98% (95%-CI: 92%-100%) and diagnostic odds ratio of 36 (95% CI: 9-133). Of DNA methylation patterns, hypermethylation of CDKN2A, NPTX2 and ppENK were studied most. Hypermethylation of NPTX2 performed best with a sensitivity of 39-70% and specificity of 94-100% for distinguishing pancreatic cancer from controls. CONCLUSIONS: This meta-analysis shows that, in pancreatic juice, the presence of distinct DNA mutations (TP53, SMAD4 or CDKN2A) and NPTX2 hypermethylation have a high specificity (close to 100%) for the presence of high-grade dysplasia or pancreatic cancer. However, the sensitivity of these DNA alterations is poor to moderate, yet may increase if they are combined in a panel.

Optimization of Isolation Method for Extracellular Vesicles from Pancreatic Juice and Impact of Protease Activity.

BACKGROUNDS: Pancreatic juice (PJ) is directly associated with pancreatic lesions, including pancreatic ductal cancer and intraductal papillary mucinous neoplasm-derived cancer. Therefore, EVs secreted from these lesions into PJ can be promising biomarkers for early diagnosis. However, there are limited data from analysis of EVs in PJ samples. AIMS AND METHODS: We aimed to determine the stability of EVs in PJ collected using endoscopic naso-pancreatic drainage (ENPD) tubes as well as catheter during endoscopic retrograde cholangiography (ERCP), with or without the impact of positive protease activity, and optimize the EV isolation method. RESULTS: Size exclusion chromatography was found to be an optimal isolation method for EVs in PJ as it achieved higher recovery and purity of EVs compared with differential ultracentrifugation and polymer-based precipitation. Approximately 40% of the PJ samples collected during ERCP and more than 90% of those collected using ENPD tubes had positive protease activity. In vitro exposure to room temperature for less than 3 h was harmless to the structure of double-membrane EVs in PJ and the expression levels of TSG101, even with positive protease activity. CONCLUSIONS: We clarified the physiobiological status of EVs in PJ and optimized the EV isolation method using suitable PJ samples; these findings can be utilized to discover biomarkers for cancer diagnosis and elucidate their function.

Pathological and molecular diagnoses of early cancer with bile and pancreatic juice.

The dismal prognosis of pancreaticobiliary malignancies is mainly attributed to the extremely difficult detection of early-stage lesions, including intraepithelial neoplasia. To improve prognosis, several studies on the early detection of cancer have been conducted using bile and pancreatic juices for pathological or molecular analyses. One approach is liquid biopsy that includes information about the tumor, such as circulating tumor cells, circulating tumor DNA, microRNAs, and exosomes released by the tumor. Another approach is proteomics/metabolomics that reflects specific conditions in the tumor. These two approaches lead to artificial intelligence-based multiomics analyses that comprises genomics, proteomics/metabolomics, and transcriptomics. Based on the findings of molecular analysis, pathological analysis using immunohistochemical staining/fluorescence in situ hybridization has also been developed. Moreover, there have been reports of new methods/ingenuities for obtaining appropriate samples for the diagnosis of early-stage cancer. Here we review the knowledge on cutting-edge pathological and molecular analyses of bile and pancreatic juices, introduce some ingenuities in sampling and sample processing to promote effective clinical practice, and provide a basis for future studies.

Endoscopic approach in the diagnosis of high-grade pancreatic intraepithelial neoplasia.

Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) is essential for improving prognosis; however, diagnosing PDAC at an early stage is challenging. In patients with localized high-grade pancreatic intraepithelial neoplasia (HG-PanIN), whose tumorous lesion is undetectable on cross-sectional images such as computed tomography or magnetic resonance image, long-term survival is expected. Pancreatic cystic lesions or main pancreatic duct (MPD) dilatation are important indirect findings for the initial diagnosis of HG-PanIN. Magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasound (EUS) should play important roles in detecting abnormal image findings, such as local irregular MPD stenosis, caliber MPD changes, small cystic lesions, or branch duct dilatation. Additionally, EUS could detect hypoechoic areas around the MPD stenosis in some patients with HG-PanIN. Subsequently, endoscopic retrograde cholangiopancreatography (ERCP) and its associated pancreatic juice cytology, including serial pancreatic juice aspiration cytologic examination (SPACE) after placement of an endoscopic nasopancreatic drainage (ENPD) tube, may have high diagnostic accuracy for confirming the malignancy in HG-PanIN. Although ERCP and its associated pancreatic cytology, including SPACE, may be associated with post-ERCP pancreatitis (PEP), a recent randomized trial suggested that a 4-Fr ENPD tube may reduce the incidence of PEP. In the future, further prospective multicenter studies are required to establish a standard method of SPACE. Additionally, further studies for novel biomarkers could help to establish evolutionary methods with duodenal fluid and pancreatic juice for the early and accurate diagnosis of early-stage PDAC.

Pancreatobiliary Flow Dynamics: Association Between Bile and Pancreatic Juice Evaluated With Cine-Dynamic Magnetic Resonance Cholangiopancreatography Using Spatially Selective Inversion Recovery Pulse.

BACKGROUND: The physiological flow patterns and the reciprocal relationship between pancreatic juice and bile excretion dynamics have not been clearly elucidated by imaging. PURPOSE: To assess the physiological flow patterns of bile and pancreatic juice simultaneously in order to clarify the pancreatobiliary flow dynamics using cine-dynamic magnetic resonance cholangiopancreatography (MRCP) with a spatial selective inversion recovery (IR) pulse. STUDY TYPE: Retrospective. POPULATION: A total of 85 patients with physiologically normal pancreatobiliary flow without ductal dilatation (normal group) and 19 patients with dilated pancreatic duct. FIELD STRENGTH/SEQUENCE: A 3 T, fast spin echo sequence with IR pulse to nullify the signal of static pancreatic juice and bile. ASSESSMENT: The frequency and secretion grade of the antegrade and reverse flow of the pancreatic juice and bile on cine-dynamic MRCP were visually evaluated. Additionally, the reciprocal relationship between pancreatic juice and bile flow was evaluated based on its flow patterns. STATISTICAL TESTS: Spearman's rank correlation coefficient analysis and the Kruskal-Wallis and Mann-Whitney U tests were used. P values of <0.05 were considered to indicate statistical significance. RESULTS: In the normal group, the antegrade pancreatic juice flow and no bile flow pattern was most frequently observed (29%), followed by the no pancreatic juice flow and no bile flow pattern (23%), the antegrade pancreatic juice flow and antegrade bile flow pattern (22%), and the no pancreatic juice flow and reverse bile flow pattern (9%). The flow of the pancreatic juice and bile were synchronized with each other in 47%, while they were not in 53%. In the dilated pancreatic duct group, the mean secretion grade of the antegrade bile and pancreatic juice flow was significantly lower than in the normal group. DATA CONCLUSION: Cine-dynamic MRCP with a spatially selective IR pulse can visualize the variations of the physiological flow patterns of bile and pancreatic juice including 53% of unsynchronized patterns. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 5.

Intraoperative amylase level of pancreatic juice as a simple predictor of pancreatic fistula after pancreaticoduodenectomy.

INTRODUCTION: A soft remnant texture of the pancreas is commonly accepted as a risk factor for postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD). However, its assessment is subjective. The aim of this study was to evaluate the significance of intraoperative amylase level of the pancreatic juice as a risk factor of POPF after PD. METHOD: This study included 75 patients who underwent PD between November 2014 and April 2020 at Jikei University Hospital. We investigated the relationship between pancreatic texture, intraoperative amylase level of pancreatic juice, results of the pathological evaluations, and the incidence of POPF. RESULTS: Twenty-three patients (31%) developed POPF. The significant predictors of POPF were non-ductal adenocarcinoma (p < 0.01), soft pancreatic remnant (p < 0.01), high intraoperative blood loss (p < 0.01), high intraoperative amylase level of pancreatic juice (p < 0.01), and low pancreatic fibrosis (p < 0.01). Multivariate analysis revealed that the significant independent predictors of POPF were high intraoperative blood loss (p < 0.01) and high intraoperative amylase level of pancreatic juice (p = 0.02). Receiver operating characteristic (ROC) analysis showed that the cut-off value for the intraoperative amylase level of pancreatic juice was 2.17 × 105 IU/L (area under the curve = 0.726, sensitivity = 95.7%, and specificity = 50.0%) CONCLUSIONS: The intraoperative amylase level of pancreatic juice is a reliable objective predictor for POPF after PD.

MiR-10a in Pancreatic Juice as a Biomarker for Invasive Intraductal Papillary Mucinous Neoplasm by miRNA Sequencing.

New biomarkers are needed to further stratify the risk of malignancy in intraductal papillary mucinous neoplasm (IPMN). Although microRNAs (miRNAs) are expected to be stable biomarkers, they can vary owing to a lack of definite internal controls. To identify universal biomarkers for invasive IPMN, we performed miRNA sequencing using tumor-normal paired samples. A total of 19 resected tissues and 13 pancreatic juice samples from 32 IPMN patients were analyzed for miRNA expression by next-generation sequencing with a two-step normalization of miRNA sequence data. The miRNAs involved in IPMN associated with invasive carcinoma were identified from this tissue analysis and further verified with the pancreatic juice samples. From the tumor-normal paired tissue analysis of the expression levels of 2792 miRNAs, 20 upregulated and 17 downregulated miRNAs were identified. In IPMN associated with invasive carcinoma (INV), miR-10a-5p and miR-221-3p were upregulated and miR-148a-3p was downregulated when compared with noninvasive IPMN. When these findings were further validated with pancreatic juice samples, miR-10a-5p was found to be elevated in INV (p = 0.002). Therefore, three differentially expressed miRNAs were identified in tissues with INV, and the expression of miR-10a-5p was also elevated in pancreatic juice samples with INV. MiR-10a-5p is a promising additional biomarker for invasive IPMN.

Förster resonance energy transfer (FRET)-Labeled nanoprobe enables real-time diagnosis of pancreatic juice activation due to postoperative pancreatic fistula.

OBJECTIVES: Postoperative pancreatic fistula (POPF) subsequent to pancreatectomy often causes activation of pancreatic juice, resulting in serious complications. In POPF, the types of pancreatic juices found are active and inactive, and the identification of these two types of pancreatic juice greatly contributes to the development of postoperative management after pancreatectomy. This study reports favorable results of the clinical application of the Förster resonance energy transfer (FRET) nanoprobe that was independently developed to distinguish between the active and inactive types of pancreatic juice. METHODS: The FRET nanoprobe developed was a nanoprotein capsule. It exuded a red color when the capsule structure was maintained. When activated protease in the pancreatic juice acts on it, the capsules are reduced quantitatively and FRET is abolished, resulting in a change in color from red to green. Pancreatic juice activation can be measured by the FRET signal. A total of 117 drainage fluid samples from 16 postpancreatoduodenectomy cases were obtained and evaluated. RESULTS: The diagnosis of pancreatic juice activation was possible using the FRET signal with a cut-off value of 1.6. Pancreatic juice activation was not associated with drainage fluid amylase (AMY) levels. The results demonstrated that pancreatic juice was activated when drainage fluid was infected. CONCLUSION: The use of a FRET nanoprobe enabled real-time detection of the presence or absence of pancreatic juice activation in pancreatic fistula after pancreatic surgery. There was an adequate correlation between infection and pancreatic juice activation regardless of drain AMY levels.

Value of repeated cytology for intraductal papillary mucinous neoplasms of the pancreas with high risk potential of malignancy: Is it a promising method for monitoring a malignant transformation?

OBJECTIVES: The efficacy of and indications for cytological reexamination to detect malignant changes in branch duct type intraductal papillary mucinous neoplasms (BD-IPMNs) have not been studied in detail. We conducted a retrospective study to evaluate the efficacy and indications of cytological reexamination by using pancreatic juice (repeated cytology) for BD-IPMNs. METHODS: Forty-five patients who underwent repeated cytology after a diagnosis of benignancy by using initial cytology were recruited for this study. RESULTS: Thirty-eight patients, excluding 7 patients with lack of surveillance period after the final cytology, were classified into Malignancy (n = 13) and Benignancy groups (n = 25) on the bases of the findings from resected specimens or changes in BD-IPMNs after repeated cytology. The sensitivity and specificity to detect malignant changes in BD-IPMNs by using repeated cytology were 62% and 100%, respectively. For the 12 patients with mural nodules (MNs) ≥ 5 mm (67% of them were malignant), the sensitivity was 50%, whereas, for the 26 patients without MNs ≥ 5 mm (19% of them were malignant), it was 80%. In addition, malignant changes in BD-IPMNs after initial cytology occurred in 62% of the patients with changes in the MNs and 27% of the patients with an increase in the cyst size. CONCLUSION: Repeated cytology can play a role in the determination for surgery even after a diagnosis of benignancy by using initial cytology, especially for BD-IPMNs without MNs ≥5 mm. In addition, changes in the MNs or cyst size may be appropriate indications for repeated cytology.

Focal parenchymal atrophy of pancreas: An important sign of underlying high-grade pancreatic intraepithelial neoplasia without invasive carcinoma, i.e., carcinoma in situ.

OBJECTIVES: Diagnosing high-grade intraepithelial neoplasia without invasion, traditionally referred to as carcinoma in situ (CIS), is essential for improving prognosis. We examined the imaging findings of patients with and without CIS to identify significant aspects for the diagnosis of CIS. METHODS: Forty-six patients strongly suspected of early pancreatic cancer without nodule on imaging (CIS group, n = 27; non-malignant group, n = 19) were retrospectively evaluated according to ten factors of computed tomography/magnetic resonance imaging (CT/MRI), endoscopic ultrasonography (EUS), and endoscopic retrograde cholangiopancreatography (ERCP) using hierarchical cluster and univariate analyses. RESULTS: Two clusters were formed by hierarchical cluster analysis. One cluster consisted of 83.3% CIS cases with similar image findings such as focal pancreatic parenchymal atrophy (FPPA) on CT/MRI, main pancreatic duct (MPD) stricture surrounded by hypoechoic areas on EUS, and MPD stricture with upstream MPD dilation on ERCP. On univariate analysis, the CIS and non-malignant groups had FPPA on CT/MRI in 15 (55.6%) and 3 (15.8%) cases (p = 0.013), and MPD stricture surrounded by hypoechoic areas on EUS in 20 (74.1%) and 4 (21.1%) cases (p = 0.001), respectively. MPD stricture surrounded by hypoechoic areas was observed in 80% (12/15) of CIS cases with FPPA on CT/MRI and correlated with FPPA. Moreover, FPPA and MPD stricture surrounded by hypoechoic areas had histopathologically observed fibrosis or fat replacement due to pancreatic parenchymal atrophy. CONCLUSIONS: FPPA and MPD stricture surrounded by hypoechoic areas are significant findings for the diagnosis of CIS.

Focal Parenchymal Atrophy and Fat Replacement Are Clues for Early Diagnosis of Pancreatic Cancer with Abnormalities of the Main Pancreatic Duct.

Pancreatic cancer is one of the most dangerous solid tumors, but its early diagnosis is difficult. The abnormality of the main pancreatic duct (MPD), such as a single localized stricture and upstream dilatation, might be useful in the early detection of pancreatic cancer. However, these findings are often observed in benign inflammatory cases. This study aimed to clarify whether early pancreatic cancer presenting MPD abnormalities has characteristic features different from those of benign cases. This is a single-center, retrospective study. We analyzed 20 patients who underwent pancreatectomy presenting with a single, localized MPD stricture without identifiable masses on imaging: 10 patients with pancreatic ductal adenocarcinoma (cancer group; 6 with stage 0 and 4 with stage I) and 10 patients with benign strictures (benign group; 8 with inflammation and 2 with low-grade pancreatic intraepithelial neoplasms). Pancreatectomy was performed in these benign cases because high-grade intraepithelial neoplasm was suspected. Although the proportion of patients with diabetes mellitus tended to be higher in the cancer group (6/10) than that in the benign group (1/10) (P = 0.058), other clinical characteristics were not different between the groups. Preoperative cytological malignancies were detected in four patients in the cancer group (4/10) but not in the benign group (P = 0.09). Focal parenchymal atrophy and fat replacement were more frequently detected on computed tomography in the cancer group (7/10) than in the benign group (1/10) (P = 0.02). In conclusion, focal parenchymal atrophy and fat replacement may provide clues for the early diagnosis of pancreatic cancer.

Surgical strategy for intraductal papillary mucinous neoplasms of the pancreas.

The current treatment strategy for intraductal papillary mucinous neoplasms (IPMNs), based on the international consensus guideline, has been accepted widely. However, reported outcomes after surgical resection for IPMN show that once the tumor progresses to invasive intraductal papillary mucinous carcinoma (IPMC), recurrence is not uncommon. The surgical treatment for IPMN is invasive and sometimes followed by complications. Therefore, the best timing for resection might be at the point when high-grade dysplasia (HGD) is evident. According to previous reports, main duct type IPMN has a high malignant potential and its surgical resection is universally accepted, whereas, the incidence of HGD/invasive IPMC in branch duct and mixed type IPMNs is thought to be lower. In addition to mural nodules and a dilated main pancreatic duct, cytology and measurement of the carcinoembryonic antigen level in the pancreatic juice might be useful to differentiate HGD/invasive IPMC from low-grade dysplasia. The nomogram proposed recently to predict the risk of HGD/invasive IPMC in IPMN patients might help surgeons decide on the best treatment strategy, depending on the patient's age and general condition. Second resection for high-risk lesions in the remnant pancreas might improve the survival of IPMN patients.

Perforation of anastomotic peptic ulcer following pancreaticoduodenectomy: a report of three cases.

BACKGROUND: Perforation of a marginal peptic ulcer after pancreaticoduodenectomy (PD) can lead to severe conditions, although its clinical features have not been well reported. In this article, we present three cases of marginal peptic ulcer perforation after PD that we experienced in our institute and attempt to clarify its appropriate treatment and prevention. CASE PRESENTATION: Marginal ulcer perforation confirmed with computed tomography and/or surgical exploration occurred in 3 (1.8%) of 163 consecutive patients who underwent PD (including 160 patients who underwent a total or subtotal stomach-preserving procedure) at our institution. The three patients (one man and two women) had a median age of 77 (65-79) years. Two of these patients had a medical history of duodenal peptic ulcer. All three patients had biliary neoplasms. Two of the patients underwent subtotal stomach-preserving PD with antro-jejunal anastomosis, and the other patient underwent pylorus-preserving PD with duodenal jejunostomy. The perforation occurred with a sudden and severe onset of abdominal pain 34, 94, and 1204 days, respectively, after the PDs. At the time of the perforation, all of the patients had been withdrawn from postoperative prophylactic antipeptic ulcer agents, with the cessation periods ranging from 12 to 1008 days. In addition, all the patients were in fasting conditions for 1 to 13 days just before the perforation. Surgical treatment with direct suturing of the perforated ulcer was performed for two patients, while conservative therapy was performed for one patient. Their primary treatment courses were satisfactory. Chronic antisecretory agent therapy was prescribed for 562, 271, and 2370 days, respectively, from marginal ulcer perforation, and no ulcer recurrence was noted in any of the patients. CONCLUSIONS: Lack of antisecretory therapy and fasting were considered an essential cause of marginal peptic ulcer perforation after PD. In addition, unlike the native duodenum, the jejunal limb used for reconstruction to a preserved stomach may be at increased risk of ulceration. Chronic permanent administration of antisecretory agents and fasting avoidance are desirable for patients who have undergone stomach-preserving PD to prevent marginal ulcer perforation.