Value of endoscopy for early diagnosis of pancreatic carcinoma

Variable Curvature Flexible Transducer for Abdominal Expandable Imaging

Expanding the imaging field of view (FOV) of medical ultrasound transducers will more effectively detect pathological behaviors of tissues or organs. Conventional rigid transducers can be realized by increasing the number of array elements or the curvature; however, the imaging aperture is fixed by the original size and shape during the manufacturing process. This article presented a 128-element, 3-MHz flexible curvature abdominal array (FCAA) with the goal of dynamically expanding the FOV within a 120° range. The piezoelectric stack was divided into small pitches through a double-cut process, and two-component viscoelastic substrates (TCVSs) were filled between adjacent array elements to generate tensile and compressive stresses during decomposition deformation. A 3-D-printed push-pull device provides sufficient mechanical support, resulting in a conformal minimum curvature radius of 46 mm. The innovative rigid-flexible composite backing layer was used to balance mechanical flexibility and high bandwidth (BW) of -6 dB to 67.6%. The results showed that the axial and lateral resolutions of the commercial phantom line target are 0.35 and 0.77 mm, respectively, and the axial and lateral resolutions of FOV 120° are 0.36 and 1.02 mm, respectively. The imaging performance of FCAA was verified by B-model imaging of the kidneys, intestines, uterus, and bladder of volunteers with a different body mass index (BMI). In addition, the 5-mm renal artery phantom verified the Doppler imaging function of FCAA. All the results demonstrated that FCPA has great potential clinical value in abdominal ultrasound and gynecological examination.

Pancreatic cancer: Future challenges and new perspectives for an early diagnosis

This editorial is a commentary on the case report by Furuya et al focusing on the challenging diagnosis of early pancreatic adenocarcinoma and new tools for an earlier diagnosis. Currently, pancreatic cancer still has a poor prognosis, mainly due to late diagnosis in an advanced stage. Two main precancerous routes have been identified as pathways to pancreatic adenocarcinoma: The first encompasses a large group of mucinous cystic lesions: intraductal papillary mucinous neoplasm and mucinous cystic neoplasm, and the second is pancreatic intraepithelial neoplasia. In the last decade the focus of research has been to identify high-risk patients, using advanced imaging techniques (magnetic resonance cholangiopancreatography or endoscopic ultrasonography) which could be helpful in finding "indirect signs" of early stage pancreatic lesions. Nevertheless, the survival rate still remains poor, and alternative screening methods are under investigation. Endoscopic retrograde cholangiopancreatography followed by serial pancreatic juice aspiration cytology could be a promising tool for identifying precursor lesions such as intraductal papillary mucinous neoplasm, but confirming data are still needed to validate its role. Probably a combination of cross-sectional imaging, endoscopic techniques (old and new ones) and genetic and biological biomarkers (also in pancreatic juice) could be the best solution to reach an early diagnosis. Biomarkers could help to predict and follow the progression of early pancreatic lesions. However, further studies are needed to validate their diagnostic reliability and to establish diagnostic algorithms to improve prognosis and survival in patients with pancreatic cancer.

Identification and analysis of pancreatic intraepithelial neoplasia: opportunities and challenges

Pancreatic intraepithelial neoplasia (PanIN) is the most common precursor lesion of pancreatic ductal adenocarcinoma (PDAC), which has poor prognosis with a short median overall survival of 6-12 months and a low 5-year survival rate of approximately 3%. It is crucial to remove PanIN lesions to prevent the development of invasive PDAC, as PDAC spreads rapidly outside the pancreas. This review aims to provide the latest knowledge on PanIN risk, pathology, cellular origin, genetic susceptibility, and diagnosis, while identifying research gaps that require further investigation in this understudied area of precancerous lesions. PanINs are classified into PanIN 1, PanIN 2, and PanIN 3, with PanIN 3 having the highest likelihood of developing into invasive PDAC. Differentiating between PanIN 2 and PanIN 3 is clinically significant. Genetic alterations found in PDAC are also present in PanIN and increase with the grade of PanIN. Imaging methods alone are insufficient for distinguishing PanIN, necessitating the use of genetic and molecular tests for identification. In addition, metabolomics technologies and miRNAs are playing an increasingly important role in the field of cancer diagnosis, offering more possibilities for efficient identification of PanIN. Although detecting and stratifying the risk of PanIN poses challenges, the combined utilization of imaging, genetics, and metabolomics holds promise for improving patient survival in this field.

Advances in Endoscopic Ultrasound in Pancreatic Cancer Screening, Diagnosis, and Palliative Care

Pancreatic cancer is a highly aggressive malignancy with a profoundly poor prognosis. Clinically, the condition most frequently manifests with symptoms including painless jaundice, abdominal discomfort, and back pain. Early diagnosis and the implementation of effective therapeutic strategies are critical for improving patient survival outcomes. However, merely 10-20% of patients are diagnosed at an early stage, with the majority presenting at advanced stages, often with metastasis. Consequently, early detection and intervention are crucial for enhancing prognosis. The widespread adoption of endoscopic ultrasonography (EUS) technology in recent years has significantly enhanced the diagnostic accuracy for pancreatic space-occupying lesions. EUS is increasingly recognized for its pivotal role in alleviating malignant biliary obstruction (MBO), gastric outlet obstruction (GOO), and refractory pain in advanced pancreatic cancer. This article aims to provide an overall review of the current applications of EUS in the diagnosis and treatment of pancreatic cancer, exploring its advantages and limitations in early screening, diagnosis, and palliative care. Furthermore, this review explores potential future directions in the field, aiming to provide valuable insights to inform and enhance the clinical management of pancreatic cancer.

Hyaluronic Acid-Modified and Doxorubicin-Loaded Au Nanorings for Dual-Responsive and Dual-Imaging Guided Targeted Synergistic Photothermal Chemotherapy Against Pancreatic Carcinoma

Introduction

Pancreatic carcinoma (PC) is a highly malignant digestive tumor. Nanotechnology-based minimally invasive techniques have been proposed to provide a new opportunity for PC treatment.

Methods

A minimally invasive nanoplatform (named HA/DOX-AuNRs) is fabricated by HA modifying and DOX loading Au nanorings (AuNR). Because of their complicated geometric structure and tunable localized surface plasmon resonance peak in the second near-infrared laser window (NIR-II window), HA/DOX-AuNRs exhibit fluorescence/photoacoustic and photothermal properties, dual-responsive DOX release, and tumor-targeting ability. HA/DOX-AuNRs are expected to improve the tumor therapeutic efficiency and reduce undesirable side effects through fluorescence/photoacoustic dual-imaging guided targeted synergetic photothermal chemotherapy under NIR-II irradiation.

Results

The morphological and physicochemical properties of HA/DOX-AuNRs are well-examined at first. The cytotoxicity, cellular uptake, and in vitro therapeutic effect of fluorescence/photoacoustic dual-imaging guided targeted synergetic photothermal chemotherapy are evaluated in Panc-1 cells. The in vivo biodistribution, anticancer effects, and systemic toxicity are investigated using PC xenograft models.

Discussion

HA/DOX-AuNRs significantly improve the therapeutic efficacy in a dual-responsive and dual-imaging guided targeted synergy.

Depictability of the upper gastrointestinal tract on forward‐viewing radial endoscopic ultrasonography versus standard upper esophagogastroduodenoscopy

Objectives

Esophagogastroduodenoscopy (EGD) is a widely used modality for investigating the upper gastrointestinal (GI) tract, similar to endoscopic ultrasonography (EUS) for the pancreaticobiliary system. A recent and novel forward‐viewing radial EUS has potential as an EGD. However, this potential has not yet been evaluated and reported in the literature. We compared the depictability of the upper GI tract on EUS using a standard EGD.

Methods

This was a prospective study in a single session in an identical patient and it was conducted at a single center.

Results

Sixty‐nine participants were enrolled in this study. A forward‐viewing radial EUS revealed equivalent visualizing performance compared with the standard EGD, except for the retroflex view of the three angular areas. Depiction scores of the anterior wall, lesser curvature, and posterior wall of the angulus in the retroflex view in the forward‐viewing radial EUS were 1.94 (95% confidence interval [CI], 1.36–2.52), 2.03 (95% CI, 1.48–2.58), and 1.93 (95% CI, 1.35–2.50), respectively. These scores were significantly lower compared with those of standard EGD scores of 2.97 (95% CI, 2.86–3.08), 2.97 (95% CI, 2.86–3.78), and 2.96 (95% CI, 2.83–3.09], respectively; p < 0.001). The rate of full‐mark score in these three angular areas was significantly lower in the forward‐viewing radial EUS than in the standard EGD (21/69, 30.4%; 23/69, 33.3%; 21/69, 30.4% vs. 67/69; 97.1%, 67/69; 97.1%, 66/69; 95.7%, p < 0.001 for all).

Conclusions

Although forward‐viewing radial EUS has the potential to simultaneously investigate the upper GI and pancreaticobiliary systems, it is too early to introduce it for this purpose.

Comparison of endoscopic ultrasonography with and without contrast enhancement for characterization of pancreatic tumors: a meta-analysis

Background and study aims  Endoscopic ultrasonography (EUS) is a reliable and efficient modality for detecting pancreatic tumors; however, plain EUS (P-EUS) is limited with respect to characterization of pancreatic tumors. Recently, the use of contrast-enhanced harmonic EUS (CH-EUS) has increased, and its utility for characterization of pancreatic tumors has been reported. This meta-analysis compares the diagnostic ability of P-EUS with that of CH-EUS for characterization of pancreatic tumors. Methods  A systematic meta-analysis of all potentially relevant articles in PubMed, the Cochrane library, and Google Scholar databases was performed. Fixed effects or random effects models were used to investigate pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio, with 95 % confidence intervals (CIs). Results  This meta-analysis included 719 patients who underwent CH-EUS and 723 who underwent P-EUS, from six eligible studies. The pooled estimates of sensitivity, specificity, and diagnostic odds ratio were 93 % (95 % CI, 0.90-0.95), 80 % (95 % CI, 0.75-0.85), and 57.9 (95 % CI, 25.9-130), respectively, for CH-EUS, and 86 % (95 % CI, 0.82-0.89), 59 % (95 % CI, 0.52-0.65), and 8.3 (95 % CI, 2.8-24.5) for P-EUS. The areas under the summary receiver operating characteristics curves for CH-EUS and P-EUS were 0.96 and 0.80, respectively. The diagnostic odds ratio for pancreatic cancer was 2.98 times higher on CH-EUS than on P-EUS ( P  = 0.03). Funnel plots demonstrated no publication bias. Conclusions  This meta-analysis demonstrates that CH-EUS has higher diagnostic accuracy for pancreatic cancer than P-EUS, and is thus a valuable tool for characterization of pancreatic tumors.

Emerging Role of Exosomal-Derived Long Noncoding RNAs in Human PDAC

Background

The incidence and mortality of pancreatic ductal adenocarcinoma (PDAC) are increasing recently. Most patients with PDAC are diagnosed at advanced stage because of the high invasiveness of cancer cells and the lack of typical early symptoms. Therefore, early diagnosis of PDAC is very important to improve the prognosis. Exosomes play crucial role in intercellular communication and deliver the contents to recipient cells to regulate their biological behaviors. Recent evidence suggests emerging role of exosomes in the carcinogenesis of a variety of cancers including PDAC. Long noncoding RNAs (LncRNAs) have been reported to be involved in the development of PDAC. It has been proved that LncRNAs have the potential to be biomarkers and therapeutic targets for PDAC. Moreover, increasing number of studies focus on the role of exosomal LncRNAs in PDAC.

Summary

In this review, we summarize the current status on our understanding of the role of exosomal-derived LncRNAs in the progression and metastasis of PDAC.

Key Messages

We focus on challenges in the potential of exosomal-derived LncRNAs as novel diagnostic and prognostic markers and therapeutic targets of PDAC. In addition, we provide an overview about the demonstrated important role of exosomal LncRNAs in the progression of PDAC.

Tissue harmonic versus contrast-enhanced harmonic endoscopic ultrasonography for the diagnosis of pancreatic tumors: Prospective multicenter study

OBJECTIVES

This prospective multicenter study aimed to assess and compare the accuracy of tissue harmonic endoscopic ultrasonography (TH-EUS) and contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for differentiating pancreatic carcinoma from other pancreatic tumors.

METHODS

Consecutive patients with solid pancreatic tumors were prospectively enrolled between August 2013 and December 2014. To assess the accuracy of TH-EUS and CH-EUS, we compared four parameters of TH-EUS (fuzzy edge, irregular periphery, hypoechogenicity, and heterogeneous internal echogenicity) and four parameters of CH-EUS (hypoenhancement and heterogeneous enhancement in the early and late phases, respectively) to investigate which parameter of each method was most suitable to diagnose pancreatic carcinomas. Interobserver agreement and the diagnostic ability of pancreatic carcinoma using TH-EUS and CH-EUS were assessed and compared.

RESULTS

A total of 204 patients were enrolled. For the diagnosis of pancreatic carcinoma, interobserver agreement by experts and nonexperts was 0.33-0.50 and 0.35-0.50 for TH-EUS, respectively, and 0.72-0.74 and 0.20-0.54 for CH-EUS, respectively. Irregular periphery was the most accurate diagnostic parameter among TH-EUS findings for differentiating pancreatic carcinomas, with sensitivity, specificity, and accuracy of 95.0%, 42.9%, and 78.9%, respectively. Late phase hypoenhancement was the most accurate diagnostic parameter among CH-EUS findings for differentiating pancreatic carcinomas, with sensitivity, specificity, and accuracy of 90.8%, 74.6%, and 85.8%, respectively. The accuracy of CH-EUS (late phase hypoenhancement) for diagnosis of pancreatic carcinoma was significantly higher than that of TH-EUS (irregular periphery) (p < 0.001).

CONCLUSION

In comparison with TH-EUS, CH-EUS increased the diagnostic ability and reproducibility for the diagnosis of pancreatic carcinoma. UMIN (000011124).

Individualized prognostic signature for pancreatic carcinoma validated by integrating immune-related gene pairs (IRGPs)

Increasingly attention is being given to immune molecules in pancreatic cancer. The purpose of this study was to understand the potential clinical application of immune-regulated genes (IRGs) in the stratification of prognosis and to facilitate the development of personalized prognostic information for pancreatic cancer patients. We systematically used public data to comprehensively analyze immune-regulated gene pair (IRGP) expression profiles and clinical data. In our study, IRGP signature was identified to predict the overall survival (OS) of pancreatic cancer patients. We suggested that immune genes are enriched in different risk groups. In the high-risk group, M1 macrophages and resting NK cells were significantly enriched, while the percentages of naïve B cells, resting dendritic cells, CD8 T cells and regulatory T cells (Tregs) were significantly higher in the low-risk group, and we verified these results with immunohistochemical experiments. Gene ontology (GO) analysis confirmed that the IRGP index (IRGPI) signature genes in the cohort were mostly party to sensory perception of a chemical stimulus and the adaptive immune response. The identification of these pathways provides a basis for studying the molecular mechanisms of IRGPI signaling to predict the prognosis of pancreatic cancer. Our study effectively constructed a robust IRGP signature with prognostic value for pancreatic cancer, presenting a conceivable method for deciding on a preoperative treatment.

A Novel Endoscopic Ultrasonography Imaging Technique for Depicting Microcirculation in Pancreatobiliary Lesions without the Need for Contrast-Enhancement: A Prospective Exploratory Study

Detective flow imaging endoscopic ultrasonography (DFI-EUS) provides a new method to image and detect fine vessels and low-velocity blood flow without using ultrasound contrast agents. The aim of this study was to evaluate the utility of DFI-EUS for pancreatobiliary lesions and lymph nodes. Between January 2019 and January 2020, 53 patients who underwent DFI-EUS, e-FLOW EUS, and contrast-enhanced EUS were enrolled. The ability of DFI-EUS and e-FLOW EUS to detect vessels was compared with that of contrast-enhanced EUS. This article describes the DFI technique along with our first experience of its use for vascular assessment of pancreatobiliary lesions. Vessels were imaged in 34 pancreatic solid lesions, eight intraductal papillary mucinous neoplasms (IPMNs), seven gall bladder lesions, and four swollen lymph nodes. DFI-EUS (91%) was significantly superior to e-FLOW EUS (53%) with respect to detection of vessels (p < 0.001) and for discrimination of mural nodules from mucous clots in IPMN and gallbladder lesions from sludge (p = 0.046). Thus, DFI-EUS has the potential to become an essential tool for diagnosis and vascular assessment of various diseases.

Recent advances of endoscopic retrograde cholangiopancreatography using balloon assisted endoscopy for pancreaticobiliary diseases in patients with surgically altered anatomy: Therapeutic strategy and management of difficult cases

Endoscopic retrograde cholangiopancreatography (ERCP) is an endoscopic modality established for diagnosis and treatment of pancreaticobiliary diseases. However ERCP in patients with surgically altered anatomy (SAA) has been difficult, and more invasive therapies have been primarily selected. The development of balloon assisted endoscopes (BAEs) innovatively facilitated ERCP in such patients. Recent advances of BAEs and other devices greatly contributed to increasing success of ERCP using BAEs (BAE-ERCP). Furthermore, interventions using Endoscopic Ultrasound (EUS-intervention) have been reported to be useful for pancreaticobiliary diseases in patients with SAA, which provide more options for endoscopic therapies and are also expected as a rescue therapy for difficult cases of BAE-ERCP. In order to thoroughly complete endoscopic treatment for pancreaticobiliary diseases with SAA, it is important to standardize the BAE-ERCP procedures based on the features of respective endoscopes and to establish a strategy for endoscopic treatment which includes analysis of BAE-ERCP difficult cases and selection of cases for rescue therapy. In addition, it is essential to be acquainted with the characteristics of possible adverse events of the procedure and to be able to deal with them for safe accomplishment of endoscopic treatment.

Early screening and diagnosis strategies of pancreatic cancer: a comprehensive review

Pancreatic cancer is a highly malignant digestive system tumor with a poor prognosis. Most pancreatic cancer patients are diagnosed at an advanced stage or even metastasis due to its highly aggressive characteristics and lack of typical early symptoms. Thus, an early diagnosis of pancreatic cancer is crucial for improving its prognosis. Currently, screening is often applied in high‐risk individuals to achieve the early diagnosis of pancreatic cancer. Fully understanding the risk factors of pancreatic cancer and pathogenesis could help us identify the high‐risk population and achieve early diagnosis and timely treatment of pancreatic cancer. Notably, accumulating studies have been undertaken to improve the detection rate of different imaging methods and the diagnostic accuracy of endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) which is the golden standard for pancreatic cancer diagnosis. In addition, there are currently no biomarkers with sufficient sensitivity and specificity for the diagnosis of pancreatic cancer to be applied in the clinic. As the only serum biomarker approved by the United States Food and Drug Administration, carbohydrate antigen 19‐9 (CA19‐9) is not recommended to be used in the early screening of pancreatic cancer because of its limited specificity. Recently, increasing numbers of studies focused on the discovering of novel serum biomarkers and exploring their combination with CA19‐9 in the detection of pancreatic cancer. Besides, the application of liquid biopsy involving circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), microRNAs (miRNAs), and exosomes in blood and biomarkers in urine, and saliva in pancreatic cancer diagnosis are drawing more and more attention. Furthermore, many innovative technologies such as artificial intelligence, computer‐aided diagnosis system, metabolomics technology, ion mobility spectrometry (IMS) associated technologies, and novel nanomaterials have been tested for the early diagnosis of pancreatic cancer and have shown promising prospects. Hence, this review aims to summarize the recent progress in the development of early screening and diagnostic methods, including imaging, pathological examination, serological examination, liquid biopsy, as well as other potential diagnostic strategies for pancreatic cancer.

Endoscopic Ultrasonography Diagnosis of Early Pancreatic Cancer

Early diagnosis of pancreatic cancer (PC) can improve patients’ prognosis. We aimed to investigate the utility of endoscopic ultrasonography (EUS) for the early diagnosis of PC. This study included 64 patients with PC at an early stage treated at Onomichi General Hospital between January 2007 and January 2020. Diagnostic procedures included contrast computed tomography (CT), magnetic resonance cholangiopancreatography, EUS fine-needle aspiration, and endoscopic retrograde cholangiopancreatography (ERCP) for pancreatic juice cytology. The mean age was 71.3 years. In all, 32 patients were stage 0, and 32 were stage I. As for image findings, the main pancreatic duct (MPD) stenosis was detected in several cases, although CT and MRCP seldom detected tumors. EUS had a high detection rate for stage 0 tumor lesions. The median observation period was 3.9 years. In cases with stage 0, the 1 year and 5 year survival rates were 100% and 78.9%, respectively. In cases with stage I, the 1 year and 5 year survival rates were 96.4% and 66.7%, respectively. EUS has the highest sensitivity among all imaging modalities for detecting small pancreatic tumors. Cases with MPD dilation or stenosis, especially with tumors that cannot be identified on CT and MRI, should have EUS performed. In some cases, EUS was not able to detect any tumor lesions, and ERCP-based pancreatic juice cytology should be useful for pathological diagnosis.

Single-session esophagogastroduodenoscopy and endoscopic ultrasound using a forward-viewing radial scan ultrasonic endoscope

BACKGROUND

Endoscopic ultrasound is useful for obtaining high-resolution images of pancreaticobiliary diseases, but is not readily available for physical checkups. In this study, we evaluated the safety and efficacy of single-session esophagogastroduodenoscopy and endoscopic ultrasound in the detection of upper-gastrointestinal and pancreaticobiliary diseases using a forward-viewing radial scan ultrasonic endoscope.

METHODS

A total of 148 patients who were scheduled for upper-gastrointestinal screening using an endoscope were prospectively included. All patients were examined by EUS in combination with EGD using a forward-viewing radial scan ultrasonic endoscope. The primary endpoint was the safety of the procedures. The secondary endpoints were the prevalence of diseases, the basal imaging capability of EUS, the procedure time, total dose of propofol, and the correlation between background factors and the prevalence of pancreatic disease. The imaging capability at each region was scored as 0 (invisible) to 2 (sufficient visualization to evaluate the organs).

RESULTS

Intraoperative hypotension occurred as an adverse event of intravenous anesthesia in one patient. There were 82 pancreaticobiliary findings and 165 upper-gastrointestinal findings (malignancy not included). Follicular lymphoma of the intra-abdominal lymph nodes was detected in one patient. The mean imaging scores of each section were 1.95 (pancreatic head and papilla), 2.0 (pancreatic body), 1.99 (pancreatic tail), and 1.89 (common bile duct and gallbladder). Age, history of diabetes mellitus, and smoking history were significantly associated with the prevalence of pancreatic diseases.

CONCLUSION

The simultaneous performance of EGD and EUS using a new ultrasonic endoscope is tolerable and safe for upper-gastrointestinal and pancreaticobiliary screening.