Advances in self-expandable metal stents for endoscopic ultrasound-guided interventions.

Endoscopic ultrasound (EUS)-guided interventions have evolved rapidly in recent years, with dedicated metal stents playing a crucial role in this process. Specifically, the invention of biflanged short metal-covered stents, including lumen-apposing metal stents (LAMS), and modifications in a variety of tubular self-expandable metal stents (SEMS), have led to innovations in EUS-guided interventions. LAMS or non-LAMS stents are commonly used in the EUS-guided drainage of pancreatic fluid collections, especially in cases of walled-off necrosis. Additionally, LAMS is commonly considered for drainage of the EUS-guided gallbladder or dilated common bile duct and EUS-guided gastroenterostomy. Fully or partially covered tubular SEMS with several new designs are being considered for EUS-guided biliary drainage. This review focuses on advances in SEMS for EUS-guided interventions and discusses related research results.

Revolutionizing outcomes: endoscopic ultrasound-guided gallbladder drainage using innovative electrocautery enhanced-lumen apposing metal stents for high-risk surgical patients.

This study retrospectively evaluated the outcomes of endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) using novel electrocautery-enhanced lumen-apposing metal stents (LAMS) in high-risk patients with acute cholecystitis (AC). Between January 1, 2021, and November 30, 2022, 58 high-risk surgical patients with AC underwent EUS-GBD with the novel electrocautery-enhanced LAMS. The technical success rate was 94.8% (55/58), with one case of duodenal perforation requiring surgery with complete stent migration and two of partial stent migration into the gallbladder. However, the clinical success rate was 100% (55/55). Recurrent AC occurred in 3.6% of the cases (2/55), managed with double pigtail plastic stents through the LAMS. Early AEs observed in 1.8% (1/55) due to stent obstruction. Late AEs occurred in 5.4% (3/55), including two cases of cholangitis and one of stent obstruction. For 33 patients followed over 6 months, LAMS maintenance was sustained in 30 cases. Two patients underwent double-pigtail plastic stent replacement after LAMS removal, and one underwent LAMS removal during surgery following tumor stage regression after chemotherapy for cholangiocarcinoma. The novel electrocautery-enhanced LAMS demonstrated high technical and clinical success rates in high-risk surgical patients with AC, maintaining effective gallbladder drainage with minimal AEs during long-term follow-up, thus highlighting its efficacy and safety in challenging patients.

Tailored hydration with lactated Ringer's solution for post-endoscopic retrograde cholangiopancreatography pancreatitis prevention: A randomized controlled trial.

OBJECTIVES: Aggressive hydration using lactated Ringer's solution (LRS) prevents post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). Concerns of this strategy are large volume and lengthy hydration. Our study aimed to evaluate the efficacy of tailored aggressive hydration (TAH) for PEP prevention. METHODS: In this prospective, multicenter, double-blinded, randomized trial conducted across three tertiary Korean hospitals, patients who underwent ERCP for the first-time were randomly assigned (1:1) to tailored standard hydration (TSH) and TAH groups. The TSH group received 1.5 mL/kg/h LRS during and after ERCP, whereas the TAH group was administered a 20 mL/kg bolus post-ERCP and 3 mL/kg/h during and after the procedure. Both groups were assessed for elevated serum amylase levels and pain 4-6 h after ERCP. If both were absent, hydration was discontinued. If either was present, hydration was continued at the original rate until 8 h. The primary endpoint was PEP development and was analyzed on an intention-to-treat analysis. RESULTS: A total of 344 patients were randomly assigned to treatment groups (171 to the TSH group and 172 to the TAH group). PEP was observed in 9.4% (16/171) in the TSH group and 3.5% (6/172) in the TAH group (relative risk 0.37, 95% confidence interval 0.15-0.93, p = 0.03). No difference was identified between the two groups in terms of PEP severity (p = 0.80) and complications related to volume overload (p = 0.32). CONCLUSIONS: TAH according to the presence of abdominal pain or elevated serum amylase levels at 4-6 h after ERCP is safe and prevents PEP development.

A comparison of novel electrocautery-enhanced lumen-apposing metal stents and plastic stents in EUS-guided drainage of infected walled-off necrosis: A multicenter randomized study.

BACKGROUND AND STUDY AIMS: Although lumen-apposing metal stents (LAMSs) have been increasingly used for walled-off necrosis (WON), their advantages over plastic stents (PS) in infected WON are unclear. We investigated the safety and efficacy of novel electrocautery-enhanced LAMS (EC-LAMS) for managing infected WON. PATIENTS AND METHODS: Patients who underwent endoscopic ultrasound-guided WON drainage were randomly assigned to the LAMS or PS groups. The primary outcome was the total number of direct endoscopic necrosectomy (DEN) procedures required to achieve clinical success. The secondary outcomes included technical success, clinical success, and adverse event occurrence. RESULTS: Forty-six patients were divided into the LAMS or PS groups (n=23 each). The total number of DEN procedures did not differ significantly between the PS (four procedures, interquartile range [IQR] 2.5-5.0) and LAMS groups (nine procedures, IQR: 8.0-9.0) (P=0.07). The LAMS group demonstrated a significantly higher clinical success rate than the PS group based on intention-to-treat analysis (100% vs. 73.9%, P=0.03) at 8 weeks but not at 4 weeks. No significant bleeding events were reported in the LAMS group, and one was reported in the PS group. CONCLUSIONS: We found no significant difference in the total number of DEN procedures between LAMS and PS for managing infected WON. The only statistically significant finding was a higher clinical success rate at 8 weeks for patients treated with EC-LAMS. The use of EC-LAMS did not result in any adverse events, such as bleeding or buried LAMS syndrome, within the study duration.

The role of PCSK9 in glomerular lipid accumulation and renal injury in diabetic kidney disease.

AIMS/HYPOTHESIS: Glomerular lipid accumulation is a defining feature of diabetic kidney disease (DKD); however, the precise underlying mechanism requires further elucidation. Recent evidence suggests a role for proprotein convertase subtilisin/kexin type 9 (PCSK9) in intracellular lipid homeostasis. Although PCSK9 is present in kidneys, its role within kidney cells and relevance to renal diseases remain largely unexplored. Therefore, we investigated the role of intracellular PCSK9 in regulating lipid accumulation and homeostasis in the glomeruli and podocytes under diabetic conditions. Furthermore, we aimed to identify the pathophysiological mechanisms responsible for the podocyte injury that is associated with intracellular PCSK9-induced lipid accumulation in DKD. METHODS: In this study, glomeruli were isolated from human kidney biopsy tissues, and glomerular gene-expression analysis was performed. Also, db/db and db/m mice were used to perform glomerular gene-expression profiling. We generated DKD models using a high-fat diet and low-dose intraperitoneal streptozocin injection in C57BL/6 and Pcsk9 knockout (KO) mice. We analysed cholesterol and triacylglycerol levels within the kidney cortex. Lipid droplets were evaluated using BODIPY staining. We induced upregulation and downregulation of PCSK9 expression in conditionally immortalised mouse podocytes using lentivirus and siRNA transfection techniques, respectively, under diabetic conditions. RESULTS: A significant reduction in transcription level of PCSK9 was observed in glomeruli of individuals with DKD. PCSK9 expression was also reduced in podocytes of animals under diabetic conditions. We observed significantly higher lipid accumulation in kidney tissues of Pcsk9 KO DKD mice compared with wild-type (WT) DKD mice. Additionally, Pcsk9 KO mouse models of DKD exhibited a significant reduction in mitochondria number vs WT models, coupled with a significant increase in mitochondrial size. Moreover, albuminuria and podocyte foot process effacement were observed in WT and Pcsk9 KO DKD mice, with KO DKD mice displaying more pronounced manifestations. Immortalised mouse podocytes exposed to diabetic stimuli exhibited heightened intracellular lipid accumulation, mitochondrial injury and apoptosis, which were ameliorated by Pcsk9 overexpression and aggravated by Pcsk9 knockdown in mouse podocytes. CONCLUSIONS/INTERPRETATION: The downregulation of PCSK9 in podocytes is associated with lipid accumulation, which leads to mitochondrial dysfunction, cell apoptosis and renal injury. This study sheds new light on the potential involvement of PCSK9 in the pathophysiology of glomerular lipid accumulation and podocyte injury in DKD.

Optical Tweezing Terahertz Probing for a Single Metal Nanoparticle.

Recently, extensive research has been reported on the detection of metal nanoparticles using terahertz waves, due to their potential for efficient and nondestructive detection of chemical and biological samples without labeling. Resonant terahertz nanoantennas can be used to detect a small amount of molecules whose vibrational modes are in the terahertz frequency range with high sensitivity. However, the positioning of target molecules is critical to obtaining a reasonable signal because the field distribution is inhomogeneous over the antenna structure. Here, we combine an optical tweezing technique and terahertz spectroscopy based on nanoplasmonics, resulting in extensive controllable tweezing and sensitive detection at the same time. We observed optical tweezing of a gold nanoparticle and detected it with terahertz waves by using a single bowtie nanoantenna. Furthermore, the calculations confirm that molecular fingerprinting is possible by using our technique. This study will be a prestep of biomolecular detection using gold nanoparticles in terahertz spectroscopy.

Current Diagnosis and Treatment of Acute Pancreatitis in Korea: A Nationwide Survey.

Background/Aims: : Acute pancreatitis (AP) is a leading cause of emergency hospitalization. We present the current diagnostic and therapeutic status of AP as revealed by analysis of a large multicenter dataset. Methods: : The medical records of patients diagnosed with AP between 2018 and 2019 in 12 tertiary medical centers in Korea were retrospectively reviewed. Results: : In total, 676 patients were included; of these, were 388 (57.4%) males, and the mean age of all patients was 58.6 years. There were 355 (52.5%), 301 (44.5%), and 20 (3.0%) patients with mild, moderate, and severe AP, respectively, as assessed by the revised Atlanta classification. The most common etiologies of AP were biliary issues (41.6%) and alcohol consumption (24.6%), followed by hypertriglyceridemia (6.8%). The etiology was not identified in 111 (16.4%) patients at the time of initial admission. The overall mortality rate was 3.3%, increasing up to 45.0% among patients with severe AP. Notably, 70.0% (14/20) of patients with severe AP and 81.5% (154/189) of patients with systemic inflammatory response syndrome had received <4 L per day during the initial 24 hours of admission. Only 23.8% (67/281) of acute biliary pancreatitis patients underwent cholecystectomy during their initial admission. In total, 17.8% of patients experienced recurrent attacks during follow-up. However, none of the patients with acute biliary pancreatitis experienced recurrent attacks if they had undergone cholecystectomy during their initial admission. Conclusions: : This study provides insights into the current status of AP in Korea, including its etiology, severity, and management. Results: reveal disparities between clinical guidelines and their practical implementation for AP treatment.

Practice guidelines for managing extrahepatic biliary tract cancers.

Backgrounds/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions: The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Comparison of long-term outcomes of endoscopic ultrasound-guided hepaticogastrostomy and choledochoduodenostomy for distal malignant biliary obstruction: a multicenter retrospective study.

Background: Endoscopic ultrasound-guided biliary drainage (EUS-BD), classified as choledochoduodenostomy (CDS) and hepaticogastrostomy (HGS), is a feasible and effective alternative for distal malignant biliary obstruction (MBO) in failed endoscopic retrograde cholangiopancreatography. However, the preferred technique for better outcomes has not yet been evaluated. Objectives: We compared the long-term outcomes between the techniques. Design: Retrospective comparative study. Methods: We reviewed consecutive patients who underwent EUS-CDS or EUS-HGS with transmural stent placement for distal MBO between 2009 and 2022. The primary outcome was the stent patency. The secondary outcomes were technical and clinical success, adverse events (AEs) of each technique, and independent risk factors for stent dysfunction. Results: In all, 115 patients were divided into EUS-CDS (n = 56) and EUS-HGS (n = 59) groups. Among them, technical success was achieved in 98.2% of EUS-CDS and 96.6% of EUS-HGS groups. Furthermore, clinical success was 96.4% in EUS-CDS and 88.1% in EUS-HGS groups, without significant difference (p = 0.200). The mean duration of stent patency for EUS-CDS was 770.3 days while that for EUS-HGS was 164.9 days (p = 0.010). In addition, the only independent risk factor for stent dysfunction was systematic treatment after EUS-BD [hazard ratio and 95% confidence interval 0.238 (0.066-0.863), p = 0.029]. The incidence of stent dysfunction of EUS-HGS was higher than EUS-CDS (35.1% versus 18.2%, 0.071), despite no significant differences even in late AEs. Conclusion: In distal MBO, EUS-CDS may be better than EUS-HGS with longer stent patency and fewer AEs. Furthermore, systematic treatment after EUS-BD is recommended for the improvement of stent patency.

Secretory Production of the Hericium erinaceus Laccase from Saccharomyces cerevisiae.

Mushroom laccases play a crucial role in lignin depolymerization, one of the most critical challenges in lignin utilization. Importantly, laccases can utilize a wide range of substrates, such as toxicants and antibiotics. This study isolated a novel laccase, named HeLac4c, from endophytic white-rot fungi Hericium erinaceus mushrooms. The cDNAs for this enzyme were 1569 bp in length and encoded a protein of 523 amino acids, including a 20 amino-acid signal peptide. Active extracellular production of glycosylated laccases from Saccharomyces cerevisiae was successfully achieved by selecting an optimal translational fusion partner. We observed that 5 and 10 mM Ca2+, Zn2+, and K+ increased laccase activity, whereas 5 mM Fe2+ and Al3+ inhibited laccase activity. The laccase activity was inhibited by the addition of low concentrations of sodium azide and L-cysteine. The optimal pH for the 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt was 4.4. Guaiacylglycerol-ß-guaiacyl ether, a lignin model compound, was polymerized by the HeLac4c enzyme. These results indicated that HeLac4c is a novel oxidase biocatalyst for the bioconversion of lignin into value-added products for environmental biotechnological applications.

Triplex glycan quantification by metabolic labeling with isotopically labeled glucose in yeast.

Mass spectrometry-based approaches encompass a powerful collection of tools for the analysis biological molecules, including glycans and glycoconjugates. Unlike most traditional bioanalytical methods focusing on these molecules, mass spectrometry is especially suited for multiplexing, by utilizing stable-isotope labeling. Indeed, stable isotope-based multiplexing can be regarded as the gold-standard approach in reducing noise and uncertainty in quantitative mass spectrometry and quantitative analyses generally. The increasing sophistication and depth of biological questions being asked continue to challenge the practitioners of mass spectrometry method development. To understand the biological relevance of glycans, many stable isotope labeling-based mass spectrometry methods have been developed. Based on the duplex MILPIG (metabolic isotope labeling of polysaccharides with isotopic glucose), we establish here a novel triplex isotope labeling method using baker's yeast as the model system. Two differentially isotope-labeled glucoses (medium: 1-13C1 and heavy: 1,2-13C2), in addition to natural abundance glucose (light), were successfully used to label each monosaccharide ring in N-linked glycans in three different cell culture conditions, that, after sample mixing, resulted in a predictable triplet spectrum amenable for relative quantitation. We demonstrate excellent accuracy and precision of relative quantitation for a 1:1:1 mixture of glycans labeled in such a fashion. In addition, we applied triplex MILPIG to interrogate differential N-glycan profiles in tunicamycin-treated and control yeast cells and show that different N-glycans respond differently to tunicamycin.

Diagnosis and Treatment of Perihilar Cholangiocarcinoma: A National Survey from the Korean Pancreatobiliary Association.

Background/Aims: Based on their anatomy, cholangiocarcinomas (CCAs) are classified into intrahepatic, hilar, and distal CCAs. Although the diagnosis and treatment of each type of CCA are thought to be different, real-world data studies on the current practice are limited. Therefore, this study was designed to capture the current practice of diagnosing and treating perihilar CCA in Korea. Methods: We conducted a survey using an online platform. The questionnaire consisted of 18 questions designed to evaluate the current practice of diagnosing and treating perihilar CCA in Korea. The targets of this survey were biliary endoscopists who are members of the Korean Pancreatobiliary Association. Results: In total, 119 biliary endoscopists completed the survey. Of the respondents, 89.9% thought that the use of the International Classification of Diseases, 11th Revision (ICD-11) system is necessary to classify CCA. Approximately half of the respondents would recommend surgery or chemotherapy until patients were 80 years of age. For the pathological diagnosis of CCA, endoscopic retrograde cholangiopancreatography with biopsy was the most preferred modality. Routine preoperative biliary drainage was performed by 44.5% of the respondents. For operable CCAs, 64.7% of the respondents preferred endoscopic biliary drainage using plastic stents. For palliative biliary drainage, 69.7% of the respondents used plastic stents. For palliative endoscopic biliary drainage using metal stents, 63% of the respondents preferred the stent-in-stent method. Conclusions: A new coding system using the ICD-11 is needed for classifying CCAs. Guidelines for diagnosing and treating CCA based on the clinical situation in Korea are needed.

Endoscopic Gallbladder Drainage Conversion versus Conservative Treatment Following Percutaneous Gallbladder Drainage in High-Risk Surgical Patients.

Background/Aims: There are no consensus guidelines for patients with acute cholecystitis undergoing percutaneous cholecystostomy who are unfit for interval cholecystectomy. The current study aimed to compare the clinical outcomes of endoscopic gallbladder drainage, i.e. conversion from percutaneous cholecystostomy (including endoscopic transpapillary gallbladder stenting and endoscopic ultrasound-guided gallbladder drainage), and conservative treatment after percutaneous cholecystostomy tube removal. Methods: This retrospective review included patients who underwent percutaneous cholecystostomy for acute cholecystitis between January 2017 and December 2020. Consecutive patients who underwent endoscopic gallbladder drainage or percutaneous cholecystostomy tube removal without interval cholecystectomy were included. Outcome measures included recurrent acute cholecystitis and unplanned readmission due to gallstone-related diseases. Results: During the study period, 238 patients were selected (63 underwent endoscopic gallbladder drainage conversion and 175 underwent conservative treatment). Patients who underwent endoscopic gallbladder drainage conversion had lower rates of recurrent acute cholecystitis (3 [4.76%] vs 31 [17.71%], p=0.012) and unplanned readmission due to gallstone-related diseases (6 [9.52%] vs 40 [22.86%], p=0.022) than those who underwent conservative treatment following percutaneous cholecystostomy tube removal. In the univariate and multivariate analyses, calculus cholecystitis (odds ratio, 13.75; 95% confidence interval, 1.83 to 102.83; p=0.011) and conversion of endoscopic gallbladder drainage (odds ratio, 0.23; 95% confidence interval, 0.06 to 0.78; p=0.019) were significant predictive factors for recurrent acute cholecystitis. Conclusions: Endoscopic gallbladder drainage conversion led to more favorable outcomes than conservative treatment after percutaneous cholecystostomy tube removal. Therefore, endoscopic gallbladder drainage conversion may be considered a promising treatment option for patients undergoing percutaneous cholecystostomy who are at a high surgical risk.

Quality indicators of endoscopic ultrasound in the pancreatobiliary system: a brief review of current guidelines.

Since its development, the use of endoscopic ultrasonography (EUS) in the pancreas and the biliary tract has become increasingly important. The accuracy of EUS varies depending on the experience of the endoscopist. Hence, quality control measures using appropriate indicators are required to reduce these variations. American Society for Gastrointestinal Endoscopy and European Society of Gastrointestinal Endoscopy have announced the EUS quality indicators. Here, we reviewed the quality indicators of the EUS procedure in the current published guidelines.

Miniscrews position for a tissue bone borne palatal C-expander affects the displacement pattern of nasomaxillary complex: a finite element study.

This study aimed to evaluate the difference in expansion patterns based on the position of miniscrews for a tissue-bone-borne palatal C-expander using a finite element method. Ten expansion models were examined, each representing a different position of miniscrews on the palate. Models A and B had miniscrews symmetrically placed 7 mm and 15 mm below the cementoenamel junction (CEJ), respectively. Models C to J had miniscrews positioned in a triangular manner at 7 mm and 15 mm below CEJ. Stress, displacement, angular changes of the bone and teeth, and changes in the nasomaxillary complex were measured using elastoplastic behavior models through static-nonlinear simulation employing an implicit method. The anterior and posterior parts of paramidpalatal suture area were identified as ANT, TPS-M, and TPS-L, and their ratio was assessed. Model A, which featured three miniscrews located 7 mm below the CEJ, exhibited the least molar inclination and the smallest amount of skeletal expansion. Model I, with two miniscrews placed between the first and second molars, demonstrated the greatest lateral displacement at point N on the nasal cavity wall, along with the smallest ratio of ANT to TPS-M or TPS-L. This finding suggests that the posterior expansion of the palate in relation to the anterior expansion was maximized. The results of this study indicate that strategic positioning of miniscrews is effective in achieving various expansion patterns based on the targeted correction areas within the nasomaxillary complex.

Comparing zero-profile and conventional cage and plate in anterior cervical discectomy and fusion using finite-element modeling.

Conventional cage and plate (CCP) implants usually used in ACDF surgery, do have limitations such as the development of postoperative dysphagia, adjacent segment degeneration, and soft tissue injury. To reduce the risk of these complications, zero-profile stand-alone cage were developed. We used finite-element modeling to compare the total von Mises stress applied to the bone, disc, endplate, cage and screw when using CCP and ZPSC implants. A 3-dimensional FE (Finite element) analysis was performed to investigate the effects of the CCP implant and ZPSC on the C3 ~ T1 vertebrae. We confirmed that the maximum von Mises stress applied with ZPSC implants was more than 2 times greater in the endplate than that applied with CCP implants. The 3D analysis of the ZPSC model von Mises stress measurements of screw shows areas of higher stress in red. Although using ZPSC implants in ACDF reduces CCP implant-related sequalae such as dysphagia, we have shown that greater von Mises stress is applied to the endplate, and screw when using ZPSC implants. This may explain the higher subsidence rate associated with ZPSC implant use in ACDF. When selecting an implant in ACDF, surgeons should consider patient characteristics and the advantages and disadvantages of each implant type.

Prevalence, natural progression, and clinical practices of upper gastrointestinal subepithelial lesions in Korea: a multicenter study.

BACKGROUND/AIMS: This study aimed to evaluate the prevalence and natural progression of subepithelial lesions (SELs) in the upper gastrointestinal (UGI) tract. METHODS: The medical records of patients with UGI SELs who underwent endoscopic screening at eight university hospitals between January and December 2010 were retrospectively investigated. The follow-up evaluations were performed until December 2016. RESULTS: UGI SELs were found in 1,044 of the 65,233 participants screened (endoscopic prevalence, 1.60%; the total number of lesions, 1,062; mean age, 55.1±11.2 years; men, 53.6%). The median follow-up period was 48 (range, 8-74) months. SELs were most frequently found in the stomach (63.8%) and had a mean size of 9.9±6.1 mm. Endoscopic ultrasonography (EUS) was performed in 293 patients (28.1%). The most common lesions were leiomyomas, followed by gastrointestinal stromal tumors (GISTs), and ectopic pancreas. The proportions of SELs with malignant potential according to size were 3% (<1 cm), 22% (1-2 cm), 27% (2-3 cm), and 38% (≥3 cm). In gastric SELs larger than 1 cm, resections were performed in 20 patients because of an increase in size, of which 12 were found to be GISTs. CONCLUSION: The prevalence of UGI SELs was 1.60%. Further, 23% of gastric SELs ≥1 cm were precancerous lesions, most followed by EUS and clinical decisions without initial pathological confirmation.

Annotation-Efficient Deep Learning Model for Pancreatic Cancer Diagnosis and Classification Using CT Images: A Retrospective Diagnostic Study.

The aim of this study was to develop a novel deep learning (DL) model without requiring large-annotated training datasets for detecting pancreatic cancer (PC) using computed tomography (CT) images. This retrospective diagnostic study was conducted using CT images collected from 2004 and 2019 from 4287 patients diagnosed with PC. We proposed a self-supervised learning algorithm (pseudo-lesion segmentation (PS)) for PC classification, which was trained with and without PS and validated on randomly divided training and validation sets. We further performed cross-racial external validation using open-access CT images from 361 patients. For internal validation, the accuracy and sensitivity for PC classification were 94.3% (92.8-95.4%) and 92.5% (90.0-94.4%), and 95.7% (94.5-96.7%) and 99.3 (98.4-99.7%) for the convolutional neural network (CNN) and transformer-based DL models (both with PS), respectively. Implementing PS on a small-sized training dataset (randomly sampled 10%) increased accuracy by 20.5% and sensitivity by 37.0%. For external validation, the accuracy and sensitivity were 82.5% (78.3-86.1%) and 81.7% (77.3-85.4%) and 87.8% (84.0-90.8%) and 86.5% (82.3-89.8%) for the CNN and transformer-based DL models (both with PS), respectively. PS self-supervised learning can increase DL-based PC classification performance, reliability, and robustness of the model for unseen, and even small, datasets. The proposed DL model is potentially useful for PC diagnosis.