Endoscopic ultrasound guided fine needle aspiration for the diagnosis of pancreatic cystic neoplasms: a meta-analysis

Microbiome, metabolome, and ionome profiling of cyst fluids reveals heterogeneity in pancreatic cystic neoplasms

Pancreatic cystic neoplasms (PCNs) carry variable malignant potential, requiring precise clinical management. However, the heterogeneity and progression of PCNs remain poorly understood. This study analyzed the microbiome, metabolome, and ionome profiles of cyst fluids from 188 patients, including 165 with PCNs and 23 with other cyst types, using PacBio full-length 16S/ITS sequencing, LC-MS/MS, and ICP-MS. Bioinformatic analyses were performed, and metabolic enzyme and endoplasmic reticulum (ER) stress-related gene expression were examined using the PAAD TCGA dataset. PCNs were classified into distinct histopathological subtypes, including mucinous cystic lesions (MCLs) and serous cystic lesions (SCLs). MCLs demonstrated lower microbial diversity compared to SCLs, indicating microbial instability. Streptococcus and Staphylococcus were identified as key taxa in intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs), respectively. MCLs exhibited metabolic shifts towards lipid metabolism, while IPMNs showed distinct metabolic profiles potentially reflecting inflammation-related metabolic reprogramming. Ionic diversity varied among subtypes, with MCLs showing reduced diversity and IPMNs presenting broader ionic profiles. Palmitic acid (PA), a metabolite linked to Streptococcus, may contribute to pro-inflammatory metabolic alterations in IPMN. Our preliminary experiments demonstrated that co-culturing Streptococcus orails (S. orails) with ASAN-PaCa cells promoted their proliferation, accompanied by an elevation of PA levels in the supernatant. This integrative microbiome-metabolome-ionome analysis highlights histopathological heterogeneity among PCNs. While mechanistic associations remain to be fully defined, mucinous lesions may be more susceptible to microbe-driven metabolic disruption, with Streptococcus-associated lipid alterations as a potential contributing factor.

The World Health Organization Reporting System for Pancreaticobiliary Cytopathology: Review and Comparison to the Papanicolaou Society of Cytopathology System

CONTEXT.—

The World Health Organization (WHO) Reporting System for Pancreaticobiliary Cytopathology (WHO System) is the product of a joint venture between the World Health Organization, the International Academy of Cytology, and the International Agency for Research on Cancer. The WHO System revises the Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology (PSC System) and replaces the 6-tiered system with a 7-tiered system.

OBJECTIVE.—

To explain the WHO System and the differences with the PSC System.

DATA SOURCES.—

The WHO System and the PSC System of Reporting Pancreaticobiliary Cytopathology.

CONCLUSIONS.—

The diagnostic categories of the WHO System are "Insufficient/Inadequate/Nondiagnostic"; "Benign (Negative for Malignancy)"; "Atypical"; "Pancreaticobiliary Neoplasm, Low Risk/Low Grade (PaN-Low)"; "Pancreatic Neoplasm, High Risk/High Grade (PaN-High)"; "Suspicious for Malignancy"; and "Malignant." In the WHO System, the "benign" category includes both nonneoplastic and neoplastic lesions, so the "Neoplastic: Benign" category of the PSC system has been eliminated. Low-grade malignancies, pancreatic neuroendocrine tumors (PanNETs), and solid-pseudopapillary neoplasm (SPN) classified as "Neoplastic: Other" in the PSC System are classified as "Malignant" in the WHO System, leaving in the "Neoplasm" category intraductal lesions, which are divided into 2 new diagnostic categories: "Pancreaticobiliary Neoplasm (PaN)-Low Risk/Grade" and "PaN-High Risk/Grade." As with the PSC System, the WHO System advocates close correlation with imaging and encourages incorporation of ancillary testing into the final diagnosis, such as biochemical (carcinoembryonic antigen [CEA] and amylase) and molecular testing. The WHO System includes risk of malignancy per category, and reporting and diagnostic management options that recognize the variations in resources of low- and middle-income countries.

Endoscopic Ultrasound armamentarium for precise and early diagnosis of biliopancreatic lesions

The diagnostic paradigm for biliopancreatic lesions has been revolutionized by continuous advancements in endoscopic ultrasound (EUS) technologies and techniques. This review examines the expanding diagnostic toolkit available to clinicians, emphasizing innovations that have significantly enhanced precision and early detection capabilities. One of the most transformative advancements is the development of fine-needle biopsy (FNB) needles. Modern designs, including Franseen, and fork-tip configurations, have optimized tissue sampling, achieving diagnostic accuracies exceeding 90 % while minimizing the number of needle passes required. These innovations facilitate the acquisition of high-quality histological specimens suitable for comprehensive molecular profiling, paving the way for personalized therapeutic approaches. Concurrent advancements in sampling techniques have bolstered these needle design improvements. The fanning technique has been particularly effective, increasing diagnostic yields from 71 % to 88 %. Wet suction methods preserve tissue integrity better than traditional approaches, while standardized protocols for needle passes enhance procedural efficiency. For specimen evaluation, Rapid On-Site Evaluation (ROSE) offers 93 % sensitivity, while alternatives like Macroscopic On-Site Evaluation (MOSE) provide comparable accuracy while reducing dependency on specialized personnel and resources. Image enhancement technologies have markedly improved the ability to characterize lesions. Contrast Harmonic EUS (CH-EUS) is particularly effective in differentiating pancreatic cancer from other solid lesions, with meta-analyses confirming sensitivity and specificity of 94 % and 89 %, respectively. Its ability to detect lesions as small as 15 mm makes it invaluable for early diagnosis. In cystic lesions, CH-EUS excels in identifying malignant mural nodules, with diagnostic accuracies reaching 96 %. The integration of elastography and advanced digital imaging technologies has further expanded diagnostic capabilities. Strain elastography provides qualitative insights into tissue characteristics, while shear wave elastography offers quantitative measurements of stiffness, adding diagnostic precision. Similarly, technologies like detective flow imaging match the accuracy of contrast-enhanced techniques in pancreatic cancer detection and enhance vascular assessment. For cystic lesions, diagnostics have progressed beyond traditional fluid analysis. Techniques such as through-the-needle biopsy (TTNB) have improved diagnostic yields to 74 %, albeit with a modest risk of complications. Incorporating molecular markers and next-generation sequencing allows differentiation between cystic lesion subtypes and more accurate assessment of malignant potential. This array of diagnostic tools offers unprecedented potential for early and precise diagnosis of biliopancreatic lesions. Integrating these innovations into clinical practice requires careful consideration of their strengths and limitations. Future research should aim to standardize protocols and establish evidence-based algorithms for their combined use, with the ultimate goal of improving patient outcomes through earlier detection and tailored management of biliopancreatic pathologies.

Intracystic Glucose Measurement for On-Site Differentiation Between Mucinous and Non-Mucinous Pancreatic Cystic Lesions

BACKGROUND

Pancreatic cystic lesions (PCLs) are frequently detected incidentally and vary from benign to malignant. Accurate differentiation between mucinous (M-PCLs) and non-mucinous PCLs (NM-PCLs) is essential for appropriate management. This study aims to validate the accuracy of on-site glucose measurement using a glucometer with a cut-off of 50 mg/dL for distinguishing M-PCLs from NM-PCLs.

METHODS

In this prospective multicenter study, conducted at three European academic hospitals, patients who underwent endoscopic ultrasound-guided fine-needle aspiration for PCLs between 2019 and 2020 were included. On-site glucose measurement was performed using a conventional glucometer. Data on demographics, clinical features, EUS findings, and histopathology were collected.

RESULTS

Fifty patients were enrolled, with 37 having glucose levels < 50 mg/dL and 13 ≥ 50 mg/dL. M-PCLs were more common in the <50 mg/dL group (81%) compared to the ≥50 mg/dL group (23%, p < 0.001). The median CEA was higher in the <50 mg/dL group (146 ng/mL) than in the ≥50 mg/dL group (3 ng/mL, p = 0.047). On-site glucose testing < 50 mg/dl demonstrated a sensitivity of 93.2%, a specificity of 76.5%, and an accuracy of 89% for detecting M-PCLs with an AUC of 0.74 and an OR of 14.29 (p < 0.001). In comparison, CEA > 192 ng/mL had a sensitivity of 55.6%, a specificity of 87.5%, and an accuracy of 75.8% for M-PCLs, with an AUC of 0.65 and an OR of 4.44.

CONCLUSIONS

On-site glucose measurement using a glucometer with a cut-off of <50 mg/dL is a highly accurate, rapid, and cost-effective method for differentiating M-PCLs from NM-PCLs. Our results validate the glucose cut-off in a multicentric prospective cohort supporting its integration into standard diagnostic protocols for PCLs.

Optimal carcinoembryonic antigen (CEA) cutoff values in the diagnosis of neoplastic mucinous pancreatic cysts differ among assays

AIM

Pancreatic cyst fluid carcinoembryonic antigen (CEA) is a pivotal test in the diagnosis and management of neoplastic mucinous cysts (NMC) of the pancreas. Cyst fluid CEA levels of 192 ng/mL have been widely used to identify NMC. However, CEA values are unique to and significantly differ between individual assays with various optimal cutoffs reported in the literature for NMC. Here, we investigate the optimal CEA cut-off value of pancreatic cysts from two different assays to identify differences in thresholds.

METHODS

Pancreatic cyst fluid CEA levels, CEA assay platform (Beckman Dxl (BD) or Siemens Centaur XP (SC)), and clinical/pathological information were retrospectively collected. Cases were categorised into either NMC or non-NMC. Optimal CEA cut-off values were calculated via a receiver operator characteristic curve. Cut-off values were then identified separately by assay platform.

RESULTS

In total, 149 pancreatic cystic lesions with concurrent CEA values (SC: n=47; BD: n=102) were included. Histological correlation was available for 26 (17%) samples. The optimal CEA cut-off value for all samples at the study institution was 45.9 ng/mL (area under the curve (AUC)=86, Sn=85.7%, Sp=73.8%). When analysed separately by CEA assay, the cut-off values were 45.9 ng/mL (AUC=84.27, Sn=89.7%, Sp=71.4%) for BD and 24.4 ng/mL (AUC=77, Sn=81.8%, Sp=75%) for SC (p=0.48).

CONCLUSIONS

This study showed an optimal pancreas cyst CEA cut-off threshold of 45.9 ng/mL, which is lower than commonly cited literature with different cutoffs on the two separate platforms (BD: 45.9 ng/mL, SC: 24.4 ng/mL).

Imaging of pancreatic serous cystadenoma and common imitators

Pancreatic cystic neoplasms are lesions comprised of cystic components that show different biological behaviors, epidemiology, clinical manifestations, imaging features, and malignant potential and management. Benign cystic neoplasms include serous cystic neoplasms (SCAs). Other pancreatic cystic lesions have malignant potential, such as intraductal papillary mucinous neoplasms and mucinous cystic neoplasms. SCAs can be divided into microcystic (classic appearance), honeycomb, oligocystic/macrocystic, and solid patterns based on imaging appearance. They are usually solitary but may be multiple in von Hippel-Lindau disease, which may depict disseminated involvement. The variable appearances of SCAs can mimic other types of pancreatic cystic lesions, and cross-sectional imaging plays an important role in their differential diagnosis. Endoscopic ultrasonography has helped in improving diagnostic accuracy of pancreatic cystic lesions by guiding tissue sampling (biopsy) or cyst fluid analysis. Immunohistochemistry and newer techniques such as radiomics have shown improved performance for preoperatively discriminating SCAs and their mimickers.

Consensus statements on endoscopic ultrasound-guided tissue acquisition. Guidelines from the Asian Endoscopic Ultrasound Group

OBJECTIVES

This consensus was developed by the Asian EUS Group (AEG), who aimed to formulate a set of practice guidelines addressing various aspects of endoscopic ultrasound-guided tissue acquisition (EUS-TA).

METHODS

The AEG initiated the development of consensus statements and formed an expert panel comprising surgeons, gastroenterologists, and pathologists. Three online consensus meetings were conducted to consolidate the statements and votes. The statements were presented and discussed in the first two consensus meetings and revised according to comments. Final voting was conducted at a third consensus meeting. The Grading of Recommendations, Assessment, Development, and Evaluation system was adopted to define the strength of the recommendations and quality of evidence.

RESULTS

A total of 20 clinical questions and statements regarding EUS-TA were formulated. The committee recommended that fine-needle biopsy (FNB) needles be preferred over conventional fine-needle aspiration (FNA) needles for EUS-TA of subepithelial lesions. For solid pancreatic masses, rapid on-site evaluation is not routinely recommended when FNB needles are used. For dedicated FNB needles, fork-tip and Franseen-tip needles have essentially equivalent performance.

CONCLUSION

This consensus provides guidance for EUS-TA, thereby enhancing the quality of EUS-TA.

Diagnosis and Management of Pancreatic Cysts

As pancreatic cyst incidence rises, likely due to the ubiquitous increase in cross-sectional imaging, their management presents multiple challenges for both the practitioner and patient. It is critical that all pancreatic cysts are appropriately characterized, as treatment decisions depend on an accurate diagnosis. Diagnostic modalities such as cytology, biopsy, and cyst fluid biomarkers allow for definitive diagnosis of virtually all lesions. Some cysts, such as intraductal papillary mucinous neoplasms, mucinous cystic neoplasms, and cystic pancreatic endocrine neoplasms, have malignant potential and must be surveyed. Other cysts, such as serous cystadenomas and pancreatic fluid collections, do not have malignant potential. Surveillance strategies vary widely depending on cyst type and size and while multiple medical societies advocate surveillance, their published surveillance guidelines are heterogenous. Cysts with high-risk stigmata or worrisome features are usually resected, depending on the patient's surgical fitness. In patients unfit for resection, newer endoscopic ablative techniques are advocated. Controversial aspects regarding cyst management include whether surveillance can be stopped, how surveillance should be performed, and the extensive financial burden cyst management places on the health care system. Further study into the natural history of cystic lesions, including definitive determination of the rate of malignant transformation for each cyst type, is essential.

Endoscopic Ultrasound-Guided Through-the-Needle Biopsy: A Narrative Review of the Technique and Its Emerging Role in Pancreatic Cyst Diagnosis

Pancreatic cystic lesions (PCLs) pose a diagnostic challenge due to their increasing incidence and the limitations of cross-sectional imaging and endoscopic-ultrasound-guided fine-needle aspiration (EUS-FNA). EUS-guided through the needle biopsy (EUS-TTNB) has emerged as a promising tool for improving the accuracy of cyst type determination and neoplastic risk stratification. EUS-TTNB demonstrates superior diagnostic performance over EUS-FNA, providing critical preoperative information that can significantly influence patient management and reduce unnecessary surgeries. However, the procedure has risks, with an overall adverse event rate of approximately 9%. Preventive measures and further prospective studies are essential to optimize its safety and efficacy. This review highlights the potential of EUS-TTNB to enhance the diagnostic and management approaches for patients with PCLs. It examines the current state of EUS-TTNB, including available devices, indications, procedural techniques, specimen handling, diagnostic yield, clinical impact, and associated adverse events.

The World Health Organization Reporting System for Pancreaticobiliary Cytopathology: Overview and Summary

The recently published WHO Reporting System for Pancreaticobiliary Cytopathology (World Health Organization [WHO] System) is an international approach to the standardized reporting of pancreaticobiliary cytopathology, updating the Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology (PSC System). Significant changes were made to the categorization of benign neoplasms, intraductal neoplasms, mucinous cystic neoplasms, and malignant neoplasms considered low grade. Benign neoplasms, such as serous cystadenoma, categorized as Neoplastic: benign in the PSC system, are categorized as Benign/negative for malignancy in the WHO system. Pancreatic neuroendocrine tumor, solid-pseudopapillary neoplasm, and gastrointestinal stromal tumor, categorized as Neoplastic: other in the PSC system, are categorized as Malignant in the WHO System in accord with their classification in the 5th edition WHO Classification of Digestive System Tumours (2019). The two new categories of Pancreaticobiliary Neoplasm Low-risk/grade and Pancreaticobiliary Neoplasm High-risk/grade are mostly limited to intraductal neoplasms and mucinous cystic neoplasms. Low-risk/grade lesions are mucinous cysts, with or without low-grade epithelial atypia. High-risk/grade lesions contain neoplastic epithelium with high-grade epithelial atypia. Correlation with clinical, imaging, and ancillary studies remains a key tenet. The sections for each entity are written to highlight key cytopathological features and cytopathological differential diagnoses with the pathologist working in low resource setting in mind. Each section also includes the most pertinent ancillary studies useful for the differential diagnosis. Sample reports are provided for each category. Finally, the book provides a separate section with risk of malignancy and management recommendations for each category to facilitate decision-making for clinicians.

Clinical Perspectives on the Histomolecular Features of the Pancreatic Precursor Lesions: A Narrative Review

Pancreatic cancer (PC) is a lethal cancer with poor prognoses. Identifying and characterizing pancreatic cystic lesions (PCLs) in the early detection and follow-up plans is thought to help detect pancreatic malignancy. Besides, the molecular features of PCLs are thought to unravel potentials for targeted therapies. We present a narrative review of the existing literature on the role of PCLs in the early detection, risk stratification, and medical management of PC. High-grade intraductal papillary mucinous neoplasms (IPMN) and pancreatic intraepithelial neoplasia (PanIN) stage III are high-risk lesions for developing PC. These lesions often require thorough histomolecular characterization using endoscopic ultrasound (EUS), before a surgical decision is made. EUS is also useful in the risk assessment of PCLs with tentative plans-for instance, in branch-duct IPMNs (BD-IPMN)- where the final decision might change. Besides the operative decisions, recent improvements in the application of targeted therapies are expected to improve survival measures. Knowledge of molecular features has helped develop targeted therapies. In summary, the histomolecular characterization of PCLs is helpful in optimizing management plans in PC. Further improvements are still needed for the broad application of this knowledge in the clinical setting.

Fine-needle aspiration technique under endoscopic ultrasound guidance: A technical approach for RNA profiling of pancreatic neoplasms

BACKGROUND

Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) has been a longstanding challenge. The prognosis of patients with PDAC depends on the stage at diagnosis. It is necessary to identify biomarkers for the detection and differentiation of pancreatic tumors and optimize PDAC sample preparation procedures for DNA and RNA analysis. Most molecular studies are done using paraffin-embedded blocks; however, the integrity of DNA and RNA is often compromised in this format. Moreover, RNA isolated from human pancreatic tissue samples is generally of low quality, in part, because of the high concentration of endogenous pancreatic RNAse activity present.

AIM

To assess the potential of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to obtain specimens from pancreatic neoplasms for subsequent RNA molecular profiling, including next-generation sequencing (NGS).

METHODS

Thirty-four EUS-FNA samples were included in this study: PDAC (n = 15), chronic pancreatitis (n = 5), pancreatic cysts (n = 14), mucinous cysts (mucinous cystic neoplasia/intraductal papillary mucinous neoplasia) n = 7, serous cystic neoplasms n = 5, and pseudocysts n = 2. Cyst material consisted of cyst fluid and cyst wall samples obtained by through-the-needle biopsy (TTNB). Samples were stored at -80 °C until analysis. RNA purity (A260/230, A260/280 ratios), concentration, and integrity (RIN) were assessed. Real-time polymerase chain reaction was conducted on all samples, and small RNA libraries were prepared from solid mass samples.

RESULTS

RNA was successfully extracted from 29/34 (85%) EUS-FNA samples: 100% pancreatic adenocarcinoma samples, 100% chronic pancreatitis samples, 70% pancreatic fluid cyst samples, and 50% TTNB samples. The relative expression of GAPDH and HPRT were obtained for all successfully extracted RNA samples (n = 29) including low-quality RNA specimens. Low concentration and nonoptimal RIN values (no less than 3) of RNA extracted from EUS-FNA samples did not prevent NGS library preparation. The suitability of cyst fluid samples for RNA profiling varied. The quality of RNA extracted from mucinous cyst fluid had a median RIN of 7.7 (5.0-8.2), which was compatible with that from solid neoplasms [6.2 (0-7.8)], whereas the quality of the RNA extracted from all fluids of serous cystic neoplasms and TTNB samples had a RIN of 0.

CONCLUSION

The results demonstrate the high potential of EUS-FNA material for RNA profiling of various pancreatic lesions, including low-quality RNA specimens.

Fine-needle aspiration technique under endoscopic ultrasound guidance: A technical approach for RNA profiling of pancreatic neoplasms

BACKGROUND

Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) has been a longstanding challenge. The prognosis of patients with PDAC depends on the stage at diagnosis. It is necessary to identify biomarkers for the detection and differentiation of pancreatic tumors and optimize PDAC sample preparation procedures for DNA and RNA analysis. Most molecular studies are done using paraffin-embedded blocks; however, the integrity of DNA and RNA is often compromised in this format. Moreover, RNA isolated from human pancreatic tissue samples is generally of low quality, in part, because of the high concentration of endogenous pancreatic RNAse activity present.

AIM

To assess the potential of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to obtain specimens from pancreatic neoplasms for subsequent RNA molecular profiling, including next-generation sequencing (NGS).

METHODS

Thirty-four EUS-FNA samples were included in this study: PDAC (n = 15), chronic pancreatitis (n = 5), pancreatic cysts (n = 14), mucinous cysts (mucinous cystic neoplasia/intraductal papillary mucinous neoplasia) n = 7, serous cystic neoplasms n = 5, and pseudocysts n = 2. Cyst material consisted of cyst fluid and cyst wall samples obtained by through-the-needle biopsy (TTNB). Samples were stored at -80 °C until analysis. RNA purity (A260/230, A260/280 ratios), concentration, and integrity (RIN) were assessed. Real-time polymerase chain reaction was conducted on all samples, and small RNA libraries were prepared from solid mass samples.

RESULTS

RNA was successfully extracted from 29/34 (85%) EUS-FNA samples: 100% pancreatic adenocarcinoma samples, 100% chronic pancreatitis samples, 70% pancreatic fluid cyst samples, and 50% TTNB samples. The relative expression of GAPDH and HPRT were obtained for all successfully extracted RNA samples (n = 29) including low-quality RNA specimens. Low concentration and nonoptimal RIN values (no less than 3) of RNA extracted from EUS-FNA samples did not prevent NGS library preparation. The suitability of cyst fluid samples for RNA profiling varied. The quality of RNA extracted from mucinous cyst fluid had a median RIN of 7.7 (5.0-8.2), which was compatible with that from solid neoplasms [6.2 (0-7.8)], whereas the quality of the RNA extracted from all fluids of serous cystic neoplasms and TTNB samples had a RIN of 0.

CONCLUSION

The results demonstrate the high potential of EUS-FNA material for RNA profiling of various pancreatic lesions, including low-quality RNA specimens.

Contrast-enhanced guided endoscopic ultrasound procedures

Contrast-enhanced endoscopic ultrasound (CH-EUS) can overcome the limitations of endoscopic ultrasound-guided acquisition by identifying microvessels inside inhomogeneous tumours and improving the characterization of these tumours. Despite the initial enthusiasm that oriented needle sampling under CH-EUS guidance could provide better diagnostic yield in pancreatic solid lesions, further studies did not confirm the supplementary values in cases of tissue acquisition guided by CH-EUS. This review details the knowledge based on the available data on contrast-guided procedures. The indications for CH-EUS tissue acquisition include isoechoic EUS lesions with poor visible delineation where CH-EUS can differentiate the lesion vascularisation from the surrounding parenchyma and also the mural nodules within biliopancreatic cystic lesions, which occur in select cases. Additionally, the roles of CH-EUS-guided therapy in patients whose pancreatic fluid collections or bile ducts that have an echogenic content have indications for drainage, and patients who have nonvisualized vessels that need to be highlighted via Doppler EUS are presented. Another indication is represented if there is a need for an immediate assessment of the post-radiofrequency ablation of pancreatic neuroendocrine tumours, in which case CH-EUS can be used to reveal the incomplete tumour destruction.

Glucose and lactate levels are lower in EUS-aspirated cyst fluid of mucinous vs non-mucinous pancreatic cystic lesions

BACKGROUND

Distinguishing mucinous (M) pancreatic cystic neoplasms (PCNs) from non-mucinous (NM) is challenging but crucial. Low intracystic glucose level has shown diagnostic tool promise, however further investigation is needed to understand metabolic processes.

AIMS

To compare the diagnostic accuracy of intracystic glucose and CEA levels in a large cohort and explore lactate levels as potential marker.

METHODS

PCNs≥15 mm which underwent EUS-fine needle aspiration were prospectively enrolled. Glucose, CEA and lactate levels were measured. Diagnostic accuracy for M-PCN diagnosis was evaluated using surgical/cytology reports or multidisciplinary evaluations.

RESULTS

169 PCNs were included (64 % M-PCNs). Median intracystic glucose was significantly lower in M-PCNs (1 mg/dL) compared to NM-PCNs (101 mg/dL); mean intracystic CEA was significantly higher in M-PCNs (152.5 ng/mL) compared to NM-PCNs (0.3 ng/mL). ROC curve analysis revealed best glucose cut-off ≤58 mg/dL (accuracy 93.5 %) and CEA cut-off >2.5 ng/mL (accuracy 90.5 %) for M-PCNs. Intracystic lactates were significantly lower in M-PCNs correlating directly with glucose. Single glucose dosage evidenced best diagnostic accuracy respect markers combination.

CONCLUSION

Intracystic glucose demonstrated high diagnostic utility for M-PCNs differentiation, surpassing CEA. Lactate levels correlated with glucose, suggesting their uptake by M-PCNs cells. These findings contribute to a better metabolic landscape understanding glucose use as diagnostic marker.

Endoscopic Ultrasound-Guided Ablation of Premalignant Pancreatic Cysts and Pancreatic Cancer

Pancreatic cancer is on the rise and expected to become the second leading cause of cancer-related death by 2030. Up to a one-fifth of pancreatic cancers may arise from mucinous pancreatic cysts, which are frequently present in the general population. Currently, surgical resection is the only curative approach for pancreatic cancer and its cystic precursors. However, only a dismal proportion of patients are eligible for surgery. Therefore, novel treatment approaches to treat pancreatic cancer and precancerous pancreatic cysts are needed. Endoscopic ultrasound (EUS)-guided ablation is an emerging minimally invasive method to treat pancreatic cancer and premalignant pancreatic cysts. Different ablative modalities have been used including alcohol, chemotherapy agents, and radiofrequency ablation. Cumulative data over the past two decades have shown that endoscopic ablation of mucinous pancreatic cysts can lead to cyst resolution in a significant proportion of the treated cysts. Furthermore, novel data are emerging about the ability to endoscopically ablate early and locally advanced pancreatic cancer. In this review, we aim to summarize the available data on the efficacy and safety of the different EUS-ablation modalities for the management of premalignant pancreatic cysts and pancreatic cancer.

Value of Endoscopic Ultrasound-Guided Through-the-Needle Biopsy in Pancreatic Cystic Lesions. A Systematic Review and Meta-Analysis

BACKGROUND AND AIM

Endoscopic ultrasound-guided through-the-needle biopsy (EUS-TTNB) has been used over the past few years to increase diagnostic accuracy for pancreatic cystic lesions (PCLs). However, many concerns remain regarding its widespread use. This systematic review and meta-analysis aimed to pool the data from high-quality studies to evaluate the utility of EUS-TTNB in diagnosing PCLs.

METHODS

Electronic databases (PubMed, Embase, and Cochrane Library) from January 2010 through October 2022 were searched for publications addressing the diagnostic performance of EUS-TTNB in the diagnosis of pancreatic cystic lesions. Pooled proportions were calculated using fixed (inverse variance) and random-effects (DerSimonian-Laird) models.

RESULTS

The initial search identified 635 studies, of which 35 relevant articles were reviewed. We extracted data from 11 studies that met the inclusion criterion, comprising a total of 575 patients. Mean patient age was 62.25 years ± 6.12 with females constituting 61.39% of the study population. Pooled sensitivity of EUS-TTNB in differentiating a PCL as neoplastic or non-neoplastic was 76.60% (95% CI = 72.60-80. 30). For the same indication, EUS TTNB had a pooled specificity of 98.90% (95% CI = 93.80-100.00). The positive likelihood ratio was 10.28 (95% CI = 4.77-22.15), and the negative likelihood ratio was 0.26 (95% CI = 0.22-0.31). The pooled diagnostic odds ratio for EUS-TTNB in diagnosing PCLs as malignant/pre-malignant vs. non-malignant was 41.34 (95% CI = 17.42-98.08). Pooled adverse event rates were 3.04% (95% CI = 1.83-4.54) for pancreatitis, 4.02% (95% CI = 2.61-5.72) for intra-cystic bleeding, 0.94% (95% CI = 0.33-1.86) for fever, and 1.73% (95% CI = 0.85-2.91) for other minor events.

CONCLUSIONS

EUS-TTNB has good sensitivity with excellent specificity in accurately classifying PCLs as neoplastic or non-neoplastic. Adding EUS-TTNB to EUS-FNA increases the accuracy of EUS-guided approach in diagnosing PCLs. However, it could significantly increase the risk of post-procedural pancreatitis.

Endoscopic Interventions in Pancreatic Cystic Neoplasms

During the past two decades, there has been a significant evolution in endoscopic interventions in pancreatic cystic neoplasms (PCNs), ranging from diagnostic intervention (endoscopic ultrasound-guided through-the-needle biopsy [EUS-TTNB]) to therapeutic intervention (endoscopic ultrasound-guided pancreatic cystic ablation [EUS-PCA]). They have received attention as alternatives to conventional diagnostic and therapeutic modalities. EUS-TTNB can categorize PCN types accurately by providing histologic diagnoses that conventional diagnostic modalities cannot provide. As pancreatectomy entails high morbidities, EUS-PCA can be performed safely to treat PCNs in patients who refuse surgery or have high surgical risks.

A Review of Current Practices and Future Trends in Body Fluid Testing

BACKGROUND

Body fluid testing in the clinical chemistry laboratory is a cornerstone in the diagnostic workup of pathological effusions. Laboratorians may not be aware of the preanalytical workflows used in the collection of body fluids though the value is evident whenever processes change or issues arise. The analytical validation requirements can vary depending on the regulations dictated by the laboratories' jurisdiction and accreditor requirements. Much of analytical validation hinges on how useful testing is to clinical care. Usefulness of testing varies with how well established and incorporated the tests and interpretation are in practice guidelines.

CONTENT

Body fluid collections are depicted and described so clinical laboratorians have a basic appreciation of what specimens are submitted to the laboratory for testing. A review of validation requirements by major laboratory accreditation entities is presented. A review of the usefulness and proposed decision limits for common body fluid chemistry analytes is presented. Body fluid tests that show promise and those that are losing (or lost long ago) value are also reviewed.

SUMMARY

The total testing process from collection to result interpretation can be complicated and easily overlooked by the clinical laboratory. This review aims to improve the understanding and awareness of collections, validation, result interpretation, and provide an update on recent trends.

Anesthesia care provider sedation versus conscious sedation for endoscopic ultrasound-guided tissue acquisition: a retrospective cohort study

BACKGROUND/AIMS

We aimed to study the effects of sedation on endoscopic ultrasound-guided tissue acquisition.

METHODS

We conducted a retrospective study evaluating the role of sedation in endoscopic ultrasound-guided tissue acquisition by comparing two groups: anesthesia care provider (ACP) sedation and endoscopist-directed conscious sedation (CS).

RESULTS

Technical success was achieved in 219/233 (94.0%) in the ACP group and 114/136 (83.8%) in the CS group (p=0.0086). In multivariate analysis, the difference in technical success between the two groups was not significant (adjusted odds ratio [aOR], 0.5; 95% confidence interval [CI], 0.234-1.069; p=0.0738). A successful diagnostic yield was present in 146/196 (74.5%) in the ACP group and 66/106 (62.3%) in the CS group, respectively (p=0.0274). In multivariate analysis, the difference in diagnostic yield between the two groups was not significant (aOR, 0.643; 95% CI, 0.356-1.159; p=0.142). A total of 33 adverse events (AEs) were observed. The incidence of AEs was significantly lower in the CS group (5/33 CS vs. 28/33 ACP; OR, 0.281; 95% CI, 0.095-0.833; p=0.022).

CONCLUSION

CS provided equivalent technical success and diagnostic yield for malignancy in endoscopic ultrasound-guided tissue acquisition. Increased AEs were associated with anesthesia for the endoscopic ultrasound-guided tissue acquisition.

Absorbable cyst brushes

Cytobrushes are used for low-invasive sample collection and screening in multiple diseases, with a significant impact on early detection, prevention, and diagnosis. This study focuses on improving the safety of cell brushing in hard-to-reach locations by exploring brush construction from absorbable materials. We investigated the efficacy of loop brushes made of absorbable suture wires of Chirlac, Chirasorb, Monocryl, PDS II, Vicryl Rapid, Glycolon, and Catgut during their operation in conjunction with fine-needle aspiration in an artificial cyst model. PDS II brushes demonstrated the highest efficiency, while Monocryl and Catgut also provided a significant brushing effect. Efficient brushes portrayed higher flexural rigidity than their counterparts, and their efficiency was inversely proportional to their plastic deformation by the needle. Our results open avenues for safer cell biopsies in hard-to-reach locations by utilizing brushes composed of absorbable materials.

The Latest Advancements in Diagnostic Role of Endosonography of Pancreatic Lesions

Endosonography, a minimally invasive imaging technique, has revolutionized the diagnosis and management of pancreatic diseases. This comprehensive review highlights the latest advancements in endosonography of the pancreas, focusing on key technological developments, procedural techniques, clinical applications and additional techniques, which include real-time elastography endoscopic ultrasound, contrast-enhanced-EUS, EUS-guided fine-needle aspiration or EUS-guided fine-needle biopsy. EUS is well established for T-staging and N-staging of pancreaticobiliary malignancies, for pancreatic cyst discovery, for identifying subepithelial lesions (SEL), for differentiation of benign pancreaticobiliary disorders or for acquisition of tissue by EUS-guided fine-needle aspiration or EUS-guided fine-needle biopsy. This review briefly describes principles and application of EUS and its related techniques.

Pancreatic Cyst Fluid Analysis

Pancreatic cyst fluid analysis can help diagnose pancreatic cyst type and the risk of high-grade dysplasia and cancer. Recent evidence from molecular analysis of cyst fluid has revolutionized the field with multiple markers showing promise in accurate diagnosis and prognostication of pancreatic cysts. The availability of multi-analyte panels has great potential for more accurate prediction of cancer.

A brief review of the WHO reporting system for pancreaticobiliary cytopathology

The World Health Organization (WHO), the International Academy of Cytology, and the International Agency for Research on Cancer have developed an approach to standardized reporting of pancreaticobiliary cytopathology. The WHO Reporting System for Pancreaticobiliary Cytopathology (WHO System) revises the Papanicolaou Society of Cytopathology (PSC) System for Reporting Pancreaticobiliary Cytology published in 2015 and replaces the 6 PSC categories with 7 categories: "Insufficient/Inadequate/Nondiagnostic"; "Benign/Negative for malignancy"; "Atypical"; "Pancreaticobiliary neoplasm, low risk/grade (PaN-low)"; "Pancreatic neoplasm, high risk/grade (PaN-High)"; "Suspicious for malignancy"; and "Malignant". In the PSC system, there is a single category for "Neoplastic" lesions that includes 2 groups, 1 for benign neoplasms and 1 named "Neoplastic-other", dominated by premalignant intraductal neoplasms primarily intraductal papillary mucinous neoplasms and low-grade malignant neoplasms (pancreatic neuroendocrine tumors (PanNET) and solid pseudopapillary neoplasms (SPN). In the WHO System, benign neoplasms with virtually no risk of malignancy are included in the "Benign" category and low-grade malignancies (PanNET and SPN) are included in the "Malignant" category, as per the 5th edition of the WHO Classification of Digestive System Tumors, while the non-invasive pre-malignant lesions of the ducts are divided by the cytomorphological grade of the epithelium into PaN-low and PaN-high with distinctly different risks of malignancy. Within each category, key diagnostic cytopathologic features and the ancillary studies for diagnostic and prognostic evaluation, as well as the implications of diagnosis for patient care and management, are outlined. Reporting and diagnostic management options recognize the variations in the availability of diagnostic and prognostic ancillary testing modalities in low- and middle-income countries.

Blood-Based Biomarkers in the Diagnosis and Risk Stratification of Pancreatic Cysts

The use of blood-based biomarkers for the assessment of pancreatic cystic lesions is a rapidly growing field with incredible potential. CA 19-9 remains the only blood-based marker in common use, while many novel biomarkers are in early stages of development and validation. We highlight current work in the fields of proteomics, metabolomics, cell-free DNA/circulating tumor DNA, extracellular vesicles, and microRNA among others, as well as barriers to development and future directions in the work of blood-based biomarkers for pancreatic cystic lesions.

Endoscopic Imaging of Pancreatic Cysts

Pancreatic cystic lesions (PCLs) have been diagnosed with increasing frequency likely due to the widespread use of cross-sectional imaging. A precise diagnosis of the PCL is important because it helps identify patients in need of surgical resection and those who can undergo surveillance imaging. A combination of clinical and imaging findings as well as cyst fluid markers can help classify PCLs and guide management. This review focuses on endoscopic imaging of PCLs including endoscopic and endosonographic features and fine needle aspiration. We then review the role of adjunct techniques, such as microforceps, contrast-enhanced endoscopic ultrasound, pancreatoscopy, and confocal laser endomicroscopy.

CYSTIC PANCREATIC LESIONS: IMAGING VERSUS ANATOMOPATHOLOGICAL FINDINGS-HOW TO IMPROVE DIAGNOSTIC ACCURACY?

BACKGROUND

Pancreatic cystic lesions are a group of pancreatic neoplasms with different behavior and risk of malignancy. Imaging diagnosis and differentiation of these lesions remain a challenge.

AIMS

The aim of this study was to evaluate the agreement between computed tomography and/or magnetic resonance imaging and post-operative pathologic diagnoses of Pancreatic cystic lesions in a University Hospital of São Paulo State.

METHODS

A total of 39 patients with surgically diagnosed Pancreatic cystic lesions were enrolled, as a study cohort from 2009 to 2019. Preoperative radiological and final pathological diagnosis was correlated to measure computed tomography and/or magnetic resonance imaging diagnostic. Pancreatic adenocarcinoma, choledochal pancreatic cyst, mucinous cystadenoma, serous cystadenoma, intraductal papillary mucinous neoplasms, and pancreatic pseudocyst were classified as neoplastic cysts.

RESULTS

It was noted that 27 patients (69.23%) had preoperative computed tomography and magnetic resonance imaging, 11 patients (28.20%) had preoperative computed tomography only, and 1 patient had preoperative magnetic resonance imaging only. The values for diagnoses made only with computed tomography (p=0.47) and from the combination of computed tomography+magnetic resonance imaging (p=0.50) did also point to moderate agreement with the anatomopathological findings. The values pointed to a fair agreement for the diagnosis of mucinous cystadenoma (p=0.3), moderate agreement for intraductal papillary mucinous neoplasms (p= 0.41), good agreement for serous cystadenoma (p=0.79), and excellent agreement for choledochal pancreatic cyst (p=1), pancreatic pseudocyst (p=0.84), and Frantz tumor (p=1) (p<0.05).

CONCLUSIONS

The findings of computed tomography and/or magnetic resonance imaging have an equivalent diagnostic agreement with an anatomopathological diagnosis for differentiating benign from malignant Pancreatic cystic lesions and in suggesting a specific diagnosis. There is no statistical difference between the use of computed tomography alone and computed tomography+magnetic resonance imaging in the improvement of diagnostic accuracy.

Role of Endoscopic Ultrasound in the Evaluation of Pancreatic Cystic Neoplasms: A Concise Review

Pancreatic cystic lesions are being discovered as incidental lesions during cross-sectional imaging studies of the abdomen with increasing frequency. Endoscopic ultrasound is an important diagnostic modality for managing pancreatic cystic lesions. There are various types of pancreatic cystic lesions, from benign to malignant. Endoscopic ultrasound has a multifactorial role in delineating the morphology of pancreatic cystic lesions, ranging from fluid and tissue acquisition for analysis-fine needle aspiration and through-the-needle biopsy, respectively-to advanced imaging techniques, such as contrast-harmonic mode endoscopic ultrasound and EUS-guided needle-based confocal laser endomicroscopy. In this review, we will summarize and provide an update on the specific role of EUS in the management of pancreatic cystic lesions.

Diagnosis and Management of Pancreatic Cysts: A Comprehensive Review of the Literature

The prevalence of pancreatic cysts has been rising due to the widespread use of cross-sectional imaging (CT scan and MRI) of the abdomen. While most pancreatic cysts are benign and do not require treatment or surveillance, a significant minority are premalignant and rarely malignant. The risk stratification of these lesions is not straightforward, and individual risk assessment, cyst size, distribution, and alarming morphologic features (when present) can guide the next steps in management. Neoplastic pancreatic cysts are mucinous or non-mucinous. Endoscopic ultrasound with fine-needle aspiration is often required to classify pancreatic cysts into mucinous and non-mucinous cysts and to assess the malignant potential. Advances in endoscopic techniques (confocal laser endomicroscopy, microforceps biopsy) can provide a definitive diagnosis of pancreatic cysts in some cases; however, the use of these techniques involves a higher risk of adverse events.

Comparative Performance of Endoscopic Ultrasound-Based Techniques in Patients With Pancreatic Cystic Lesions: A Network Meta-Analysis

INTRODUCTION

Evidence on the comparative diagnostic performance of endoscopic ultrasound (EUS)-based techniques for pancreatic cystic lesions (PCLs) is limited. This network meta-analysis comprehensively compared EUS-based techniques for PCL diagnosis.

METHODS

A comprehensive literature search was performed for all comparative studies assessing the accuracy of 2 or more modalities for PCL diagnosis. The primary outcome was the diagnostic efficacy for mucinous PCLs. Secondary outcomes were the diagnostic efficacy for malignant PCLs, diagnostic success rate, and adverse event rate. A network meta-analysis was conducted using the ANOVA model to assess the diagnostic accuracy of each index.

RESULTS

Forty studies comprising 3,641 patients were identified. The network ranking of the superiority index for EUS-guided needle-based confocal laser endomicroscopy (EUS-nCLE) and EUS-guided through-the-needle biopsy (EUS-TTNB) were significantly higher than other techniques for differentiating mucinous PCLs; besides, EUS-TTNB was also the optimal technique in identifying malignant PCLs. The evidence was inadequate for EUS-nCLE diagnosing malignant PCLs and contrast-enhanced harmonic EUS diagnosing both mucinous and malignant PCLs. Glucose showed a high sensitivity but low specificity, and molecular analysis (KRAS, GNAS, and KRAS + GNAS mutations) showed a high specificity but low sensitivity for diagnosing mucinous PCLs. Satisfactory results were not obtained during the evaluation of the efficiency of pancreatic cyst fluid (PCF) biomarkers in detecting malignant PCLs.

DISCUSSION

For centers with relevant expertise and facilities, EUS-TTNB and EUS-nCLE were better choices for the diagnosis of PCLs. Further studies are urgently required for further improving PCF biomarkers and validating the diagnostic performance of the index techniques.

Pancreatic Cystic Neoplasms: Diagnosis and Management

Pancreatic cancer is one of the most lethal cancers, largely related to the difficulties with early detection, as it typically presents in later stages. Pancreatic cystic neoplasms (PCN) are commonly diagnosed as incidental findings on routine imaging. PCN is becoming more frequently detected with the increasing ease and frequency of obtaining cross-sectional images. Certain subtypes of pancreatic cysts have the potential to progress to malignancy, and therefore, clinicians are tasked with creating a patient-centered management plan. The decision of whether to undergo surgical resection or interval surveillance can be challenging given the criteria, including PCN size, pancreatic duct dilation, presence of a mural nodule, and clinical symptoms that play a potential role in risk stratification. Furthermore, the guidelines available from the major gastrointestinal societies all differ in their management recommendations. In this review, we detail an overview of the different types of PCNs and compare major guidelines for both diagnosis and management. We include emerging evidence for next-generation sequencing as well as confocal needle endomicroscopy to aid in the diagnosis and determination of malignancy potential and diagnosis.

Targeted next-generation sequencing of EUS-guided through-the-needle-biopsy sampling from pancreatic cystic lesions

BACKGROUND AND AIMS

Recent advances have introduced molecular subtyping of pancreatic cystic lesions (PCLs) as a possible amendment to the diagnostic algorithm. The study evaluated the feasibility and diagnostic accuracy of molecular analysis and subtyping of PCLs using the recently introduced EUS-guided through-the-needle-biopsy (TTNB) sampling.

METHODS

We prospectively included 101 patients in the study who presented with PCLs >15 mm in the largest cross-section. EUS-guided TTNB samples were obtained by a micro-biopsy forceps introduced through a 19-gauge needle. The TTNB samples were analyzed by next-generation sequencing (NGS) for point mutations in tumor suppressors and oncogenes using a 51-gene customized hotspot panel. Sensitivity and specificity were calculated with the histologic diagnosis as reference.

RESULTS

After initial microscopic evaluation of the samples, 91 patients had residual TTNB samples available for NGS. Of these, 49 harbored mutations, most frequently in KRAS and GNAS, reflecting an excess frequency of intraductal papillary mucinous neoplasms (IPMNs) in the study population. A sensitivity and specificity of 83.7% (95% confidence interval [CI], 70.3-92.7) and 81.8% (95% CI, 48.2-97.7), respectively, were demonstrated for the diagnosis of a mucinous cyst and 87.2% (95% CI, 74.2-95.2) and 84.6% (95% CI, 54.5-98.1) for the diagnosis of an IPMN.

CONCLUSIONS

Thus, molecular analysis of TTNB samples by NGS has high sensitivity and specificity for diagnosing mucinous cysts and IPMNs. Although the procedure comes with a risk of adverse events of 9.9%, TTNB samples are a robust alternative to cyst fluid for a combined histologic and molecular diagnosis of PCLs. (Clinical trial registration number: NCT03578445.).

The role of pancreatoscopy in the diagnostic work-up of intraductal papillary mucinous neoplasms: a systematic review and meta-analysis

BACKGROUND

Confirming the diagnosis, invasiveness, and disease extent of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas is challenging. The aim of this study was to summarize the literature on the efficacy and safety of peroral pancreatoscopy (POP) in the diagnosis of IPMN, including the impact of pre- and intraoperative POP on the management of IPMN.

METHODS

The EMBASE, Medline Ovid, Web of Science, Cochrane CENTRAL, and Google Scholar databases were systematically searched for articles. Eligible articles investigated cohorts of patients who underwent POP for (suspected) IPMN.

RESULTS

25 articles were identified and included in this review; with 22 of these reporting on the diagnostic yield of POP in IPMN and 11 reporting on the effect of pre- or intraoperative POP on clinical decision-making. Cannulation and observation rates, and overall diagnostic accuracy were high across all studies. Frequently reported visual characteristics of IPMN were intraductal fish-egg-like lesions, hypervascularity, and granular mucosa. Overall, the adverse event rate was 12 %, primarily consisting of post-endoscopic retrograde cholangiopancreatography pancreatitis, with a pooled rate of 10 %, mostly of mild severity. Regarding the impact of POP on clinical decision-making, POP findings altered the surgical approach in 13 %-62 % of patients.

CONCLUSION

POP is technically successful in the vast majority of patients with (suspected) IPMN, has a consistently high diagnostic accuracy, but an adverse event rate of 12 %. Data on intraoperative pancreatoscopy are scarce, but small studies suggest its use can alter surgical management. Future studies are needed to better define the role of POP in the diagnostic work-up of IPMN.

Pancreatic cyst fluid glucose: a rapid on-site diagnostic test for mucinous cysts

BACKGROUND

Pancreatic cystic fluid (PCF) analysis is frequently used for cyst diagnosis with carcinoembryonic antigen (CEA) being the most accepted biomarker. Low glucose levels in PCF were previously suggested as a marker for mucinous cysts. A bed-side glucometer is a point-of care, immediate, simple, and cheap method which requires a small volume of PCF.

OBJECTIVES

The aim of our study was to identify the optimal glucose cut-off level for identifying mucinous cysts, evaluate the diagnostic accuracy of glucose compared to CEA, and validate glucometry against reference laboratory biochemical analysis.

DESIGN

A single-center prospective cohort study.

METHODS

Consecutive patients aged 18 and older, who underwent pancreatic cyst evaluation, at the Tel Aviv Medical Center between 2016 and 2021 were analyzed. Cyst type was defined based on clinical, laboratory, and radiologic findings. Glucose was measured using laboratory biochemical analysis and two glucometers. Receiver operating characteristic analysis derived sensitivity, specificity, and accuracy were calculated and McNemar test was used to compare between methods.

RESULTS

One hundred and one PCF samples were evaluated. The areas under the receiver operating characteristics curve for identifying mucinous cysts using glucometer, glucose laboratory, and their combination were 0.88 (p < 0.001), 0.92 (p < 0.001), and 0.93 (p < 0.001), respectively. A glucose level of 87 mg/dL was identified as the optimal laboratory glucose threshold value to detect mucinous cyst with a sensitivity of 90.9%, specificity of 83.3%, and accuracy of 89.3, higher in comparison to cyst fluid CEA. Furthermore, PCF glucose levels had the strongest association with mucinous cysts.

CONCLUSION

Our findings suggest that PCF glucose level is more accurate than CEA for the diagnosis of mucinous cysts. Glucometry glucose level assessment demonstrated an excellent correlation with laboratory glucose measurements and may become a useful diagnostic test.

Clinical Utility of the Contrast-Enhanced Endoscopic Ultrasound Guided Fine Needle Aspiration in the Diagnosis of Pancreatic Cyst

Endoscopic ultrasound fine needle aspiration (EUS-FNA) cytology from an intracystic fluid is useful in the differentiation of pancreatic cysts, with low sensitivity, which increases when the solid component is targeted. The clinical utility of contrast-enhanced guided EUS-FNA (CH-EUS-FNA) in the solid component is not known. We aimed to assess the diagnostic value of CH-EUS-FNA in enhanced mural nodules and discrimination between different cysts using contrast-enhanced endoscopic ultrasound (CH-EUS). The prospective study recruited patients with pancreatic cysts with an unclear diagnosis. The CH-EUS was followed by CH-EUS-FNA. The final diagnosis was based on surgery or the correlation between clinical history, cross-sectional imaging, echoendoscopic morphology, cystic fluid analysis, and follow-up. Fifty-eight patients with pancreatic cysts were evaluated. The mucinous cysts had wall arterial enhancement more often than non- mucinous cysts (p < 0.0001), with 90.2% sensitivity and 70.6% specificity. The CH-EUS-FNA from cystic fluid and mural nodules identified mucinous cysts and malignancy with 82.4% and 84.2% sensitivity and 92% and 100% specificity. Twenty-one cysts had solid components, but only 13 were enhanced mural nodules on EUS assessment with conclusive cytology in all cases and malignancy in 76.9%. Contrast-enhanced endoscopic ultrasound should be completed in all PCN with solid components in order to avoid unnecessary EUS-FNA and to guide FNA for the identification of malignant cysts.

Utility of Cyst Fluid Carcinoembryonic Antigen in Differentiating Mucinous and Non-mucinous Pancreatic Cysts: An Updated Meta-Analysis

BACKGROUND

Mucinous pancreatic cysts are considered premalignant and managed differently compared to benign pancreatic cystic lesions. The aim of this updated meta-analysis is to assess the diagnostic accuracy of cyst carcinoembryonic antigen (CEA) in differentiating between mucinous and non-mucinous pancreatic cysts.

METHODS

Studies comparing the diagnostic accuracy of CEA (cutoff level of 192 ng/mL) in differentiating between mucinous and non-mucinous pancreatic cysts were searched in Medline, Ovid journals, Medline nonindexed citations, and Cochrane Central Register of Controlled Trials and Database of Systematic Reviews. Pooled estimates of diagnostic precision were calculated using random and fixed effects models.

RESULTS

Initial search identified 526 reference articles, of these 34 relevant articles were selected and reviewed. Data were extracted from 15 studies (n = 2063) which met the inclusion criteria. The pancreatic cystic fluid CEA level at a 192 ng/mL cutoff value had pooled specificity of 88.6% (95% CI 85.9-90.9) and pooled sensitivity was found to be 60.4% (95% CI 57.7-62.9). The pooled positive likelihood ratio was 4.5 (95% CI 2.9-6.9) and the pooled negative likelihood ratio was 0.45 (95% CI 0.38-0.52). The pooled diagnostic odds ratio, the odds of having mucinous cyst with elevated CEA, was 11.4 (95% CI 6.9-18.7). The P for chi-squared heterogeneity for all the pooled accuracy estimates was > 0.10.

CONCLUSIONS

This meta-analysis suggests that the cyst fluid CEA level at a 192 ng/mL cutoff value is highly specific in the diagnosis of mucinous cystic lesions with reasonable sensitivity.

Pancreatic Cystic Neoplasms

Early detection of high-risk pancreatic cystic lesions enables potentially curative surgical resection, and early detection of lesions without worrisome features may lead to appropriate surveillance. Regrettably, differentiating premalignant and malignant cysts from nonmalignant ones remains challenging. However, emerging additional diagnostic tools, including the needle biopsy with microforceps and needle-based confocal laser endomicroscopy, are of exciting potential along with cyst fluid analysis".

Quantitative Software Analysis of Endoscopic Ultrasound Images of Pancreatic Cystic Lesions

Endoscopic ultrasonography (EUS) is the most accurate imaging modality for the evaluation of different types of pancreatic cystic lesions. Our aim was to analyze EUS images of pancreatic cystic lesions using an image processing software. We specified the echogenicity of the lesions by measuring the gray value of pixels inside the selected areas. The images were divided into groups (serous cystic neoplasm /SCN/, intraductal papillary mucinous neoplasms and mucinous cystic neoplasms /Non-SCN/ and Pseudocyst) according to the pathology results of the lesions. Overall, 170 images were processed by the software: 81 in Non-SCN, 30 in SCN and 59 in Pseudocyst group. The mean gray value of the entire lesion in the Non-SCN group was significantly higher than in the SCN group (27.8 vs. 18.8; p < 0.0005). The area ratio in the SCN, Non-SCN and Pseudocyst groups was 57%, 39% and 61%, respectively; significantly lower in the Non-SCN group than in the SCN or Pseudocyst groups (p < 0.0005 and p < 0.0005, respectively). The lesion density was also significantly higher in the Non-SCN group compared to the SCN or Pseudocyst groups (4186.6/mm2 vs. 2833.8/mm2 vs. 2981.6/mm2; p < 0.0005 and p < 0.0005, respectively). The EUS image analysis process may have the potential to be a diagnostic tool for the evaluation and differentiation of pancreatic cystic lesions.

The molecular, immune features, and risk score construction of intraductal papillary mucinous neoplasm patients

Intraductal papillary mucinous neoplasm (IPMN) is a common pancreatic precancerous lesion, with increasing incidence in recent years. However, the mechanisms of IPMN progression into invasive cancer remain unclear. The mRNA expression data of IPMN/PAAD patients were extracted from the TCGA and GEO databases. First, based on GSE19650, we analyzed the molecular alterations, tumor stemness, immune landscape, and transcriptional regulation of IPMN progression. The results indicated that gene expression changed dramatically, specifically at the intraductal papillary-mucinous adenoma (IPMA) stage. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Kyoto Encyclopedia of Genes and Genomes (GSEA) pathway analyses showed that glycoprotein-related, cell cycle, and P53 pathways displayed the most significant changes during progression. With IPMN progression, tumor stemness increased continuously, and KRAS, ERBB3, RUNX1, and ELF3 are essential driver genes affecting tumor stemness. Motif analysis suggested that KLF4 may be a specific transcription factor that regulates gene expression in the IPMA stage, while MYB and MYBL1 control gene expression in the IPMC and invasive stages, respectively. Then, GSE19650 and GSE71729 transcriptome data were combined to perform the least absolute shrinkage and selection operator (LASSO) method and Cox regression analysis to develop an 11-gene prediction model (KCNK1, FHL2, LAMC2, CDCA7, GPX3, C7, VIP, HBA1, BTG2, MT1E, and LYVE1) to predict the prognosis of pancreatic cancer patients. The reliability of the model was validated in the GSE71729 and TCGA databases. Finally, 11 additional IPMN patients treated in our hospital were included, and the immune microenvironment changes during IPMN progression were analyzed by immunohistochemistry (IHC). IHC results suggest that Myeloid-derived suppressor cells (MDSCs) and macrophages may be key in the formation of immunosuppressive microenvironment of IPMN progression. Our study deepens our understanding of IPMN progression, especially the changes in the immune microenvironment. The findings of this work may contribute to the development of new therapeutic strategies for IPMN.

Exosomal glypican-1 is elevated in pancreatic cancer precursors and can signal genetic predisposition in the absence of endoscopic ultrasound abnormalities

BACKGROUND

Individuals within specific risk groups for pancreatic ductal adenocarcinoma (PDAC) [mucinous cystic lesions (MCLs), hereditary risk (HR), and new-late onset diabetes mellitus (NLOD)] represent an opportunity for early cancer detection. Endoscopic ultrasound (EUS) is a premium image modality for PDAC screening and precursor lesion characterization. While no specific biomarker is currently clinically available for this purpose, glypican-1 (GPC1) is overexpressed in the circulating exosomes (crExos) of patients with PDAC compared with healthy subjects or those harboring benign pancreatic diseases.

AIM

To evaluate the capacity of GPC1⁺ crExos to identify individuals at higher risk within these specific groups, all characterized by EUS.

METHODS

This cross-sectional study with a prospective unicentric cohort included 88 subjects: 40 patients with MCL, 20 individuals with HR, and 20 patients with NLOD. A control group (CG) was submitted to EUS for other reasons than pancreatic pathology, with normal pancreas and absence of hereditary risk factors (n = 8). The inclusion period was between October 2016 and January 2019, and the study was approved by the Ethics Committee of Centro Hospitalar Universitário de São João, Porto, Portugal. All patients provided written informed consent. EUS and blood tests for quantification of GPC1⁺ crExos by flow cytometry and carbohydrate antigen 19-9 (CA 19-9) levels by ELISA were performed in all subjects. EUS-guided tissue acquisition was done whenever necessary. For statistical analysis, SPSS^® 27.0 (IBM Corp., Armonk, NY, United States) version was used. All graphs were created using GraphPad Prism 7.00 (GraphPad Software, San Diego, CA, United States).

RESULTS

Half of MCLs harbored worrisome features (WF) or high-risk stigmata (HRS). Pancreatic abnormalities were detected by EUS in 10.0% and 35.0% in HR and NLOD individuals, respectively, all considered non-malignant and “harmless.” Median levels of GPC1⁺ crExos were statistically different: MCL [99.4%, interquartile range (IQR): 94.9%-99.8%], HR (82.0%, IQR: 28.9%-98.2%), NLOD (12.6%, IQR: 5.2%-63.4%), and CG (16.2%, IQR: 6.6%-20.1%) (P < 0.0001). Median levels of CA 19-9 were within the normal range in all groups (standard clinical cut-off of 37 U/mL). Within HR, individuals with a positive history of cancer had higher median levels of GPC1⁺ crExos (97.9%; IQR: 61.7%-99.5%), compared to those without (59.7%; IQR: 26.3%-96.4%), despite no statistical significance (P = 0.21). Pancreatic cysts with WF/HRS were statistically associated with higher median levels of GPC1⁺ crExos (99.6%; IQR: 97.6%-99.8%) compared to those without (96.5%; IQR: 81.3%-99.5%) (P = 0.011), presenting an area under the receiver operating characteristic curve value of 0.723 (sensitivity 75.0% and specificity 67.7%, using a cut-off of 98.5%; P = 0.012).

CONCLUSION

GPC1⁺ crExos may act as biomarker to support the diagnosis and stratification of PDAC precursor lesions, and in signaling individuals with genetic predisposition in the absence of EUS abnormalities.

Artificial intelligence for the detection of pancreatic lesions

PURPOSE

Pancreatic cancer is one of the most lethal neoplasms among common cancers worldwide, and PCLs are well-known precursors of this type of cancer. Artificial intelligence (AI) could help to improve and speed up the detection and classification of pancreatic lesions. The aim of this review is to summarize the articles addressing the diagnostic yield of artificial intelligence applied to medical imaging (computed tomography [CT] and/or magnetic resonance [MR]) for the detection of pancreatic cancer and pancreatic cystic lesions.

METHODS

We performed a comprehensive literature search using PubMed, EMBASE, and Scopus (from January 2010 to April 2021) to identify full articles evaluating the diagnostic accuracy of AI-based methods processing CT or MR images to detect pancreatic ductal adenocarcinoma (PDAC) or pancreatic cystic lesions (PCLs).

RESULTS

We found 20 studies meeting our inclusion criteria. Most of the AI-based systems used were convolutional neural networks. Ten studies addressed the use of AI to detect PDAC, eight studies aimed to detect and classify PCLs, and 4 aimed to predict the presence of high-grade dysplasia or cancer.

CONCLUSION

AI techniques have shown to be a promising tool which is expected to be helpful for most radiologists' tasks. However, methodologic concerns must be addressed, and prospective clinical studies should be carried out before implementation in clinical practice.

MicroRNAs as Indicators of Malignancy in Pancreatic Ductal Adenocarcinoma (PDAC) and Cystic Pancreatic Lesions

The dysregulation of microRNAs has recently been associated with cancer development and progression in pancreatic ductal adenocarcinoma (PDAC) and cystic pancreatic lesions. In solid pancreatic tumor tissue, the dysregulation of miR-146, miR-196a/b, miR-198, miR-217, miR-409, and miR-490, as well as miR-1290 has been investigated in tumor biopsies of patients with PDAC and was reported to predict cancer presence. However, the value of the predictive biomarkers may further be increased during clinical conditions suggesting cancer development such as hyperinsulinemia or onset of diabetes. In this specific context, the dysregulation of miR-486 and miR-196 in tumors has been observed in the tumor tissue of PDAC patients with newly diagnosed diabetes mellitus. Moreover, miR-1256 is dysregulated in pancreatic cancer, possibly due to the interaction with long non-coding RNA molecules that seem to affect cell-cycle control and diabetes manifestation in PDAC patients, and, thus, these three markers may be of special or “sentinel value”. In blood samples, Next-generation sequencing (NGS) has also identified a set of microRNAs (miR-20a, miR-31-5p, miR-24, miR-25, miR-99a, miR-185, and miR-191) that seem to differentiate patients with pancreatic cancer remarkably from healthy controls, but limited data exist in this context regarding the prediction of cancer presences and outcomes. In contrast to solid pancreatic tumors, in cystic pancreatic cancer lesions, as well as premalignant lesions (such as intraductal papillary neoplasia (IPMN) or mucinous-cystic adenomatous cysts (MCAC)), the dysregulation of a completely different expression panel of miR-31-5p, miR-483-5p, miR-99a-5p, and miR-375 has been found to be of high clinical value in differentiating benign from malignant lesions. Interestingly, signal transduction pathways associated with miR-dysregulation seem to be entirely different in patients with pancreatic cysts when compared to PDAC. Overall, the determination of these different dysregulation “panels” in solid tumors, pancreatic cysts, obtained via fine-needle aspirate biopsies and/or in blood samples at the onset or during the treatment of pancreatic diseases, seems to be a reasonable candidate approach for predicting cancer presence, cancer development, and even therapy responses.

Lower cyst fluid carcinoembryonic antigen cutoff is helpful in the differential diagnosis of mucinous versus non-mucinous pancreatic cysts

BACKGROUND AND AIM

Pancreatic cystic lesions (PCLs) are being diagnosed with increased frequency and have varying neoplastic potential. We conducted this multimodal, prospective study to evaluate  the role of tumor cytology and molecular markers to differentiate PCL subtypes.

METHODS

Consecutive undiagnosed patients with PCLs (n = 100, mean age: 50.37 years; 41% males) were prospectively studied. Cyst fluid carcinoembryonic antigen (CEA), CA19.9, CA125, CA72.4, and vascular endothelial growth factor-alpha (VEGF-α) levels were measured by quantitative enzyme-linked immunosorbent assay (ELISA) method. Mutational analysis of the KRAS gene (exon 2, Codon 12 and 13) and GNAS gene (Exon 8, Codon 201) were performed by Sanger's sequencing.

RESULTS

The mean cyst size was 4.32 ± 2.4 cm. Fluid cytology revealed definitive diagnosis in 21 (22.3%) patients. All malignant PCLs could be identified on cytology whereas 10/14 (71%) non-malignant mucinous PCLs could also be identified on cytology based on mucin staining. Among the tested tumor markers, cyst fluid CEA had the best diagnostic performance for differentiation between mucinous and non-mucinous PCLs (AUC 0.933 [95% CI 0.86-0.91]). At a cyst fluid CEA cutoff level of 45.0 ng/mL, the sensitivity, specificity, positive predictive value, and negative predictive value for differentiation between mucinous and non-mucinous cysts were 88.5%, 96.8%, 92.0%, and 95.3%, respectively (p &lt; 0.05). KRAS and GNAS mutation had no significant diagnostic benefit in comparison to fluid cytology and CEA levels.

CONCLUSIONS

Fluid CEA at a lower cutoff of 45 ng/mL is the most accurate marker to differentiate between mucinous and non-mucinous PCL. The KRAS and GNAS mutational analysis does not improve upon the diagnostic performance of fluid cytology and tumor markers.

Comparison of Society Guidelines for the Management and Surveillance of Pancreatic Cysts: A Review

IMPORTANCE

The identification of incidental pancreas cystic lesions (PCLs) has increased in recent decades with the expanded use and improved sensitivity of cross-sectional imaging. Because the overall risk of malignancy associated with PCLs is low, yet the relative morbidity of pancreatic surgery is high, evidence-based guidelines are necessary for appropriate surveillance and management. Therefore, this article provides a review of existing guidelines regarding surveillance and management of PCLs and highlights recent advances in the diagnostic evaluation of cysts and the postresection management of mucinous lesions.

OBSERVATIONS

There are 5 main guidelines related to the management of PCLs: the American Gastrointestinal Association (AGA) guidelines, the American College of Gastroenterology (ACG) guidelines, the American College of Radiology (ACR) recommendations, the European evidence-based guidelines, and the International Association of Pancreatology (IAP)/Fukuoka guidelines. These guidelines are based on retrospective studies that do not account or control for most tumor- and patient-specific factors. These guidelines also vary in scope, recommendations for surgical resection vs surveillance, as well as duration and type of follow-up.

CONCLUSIONS AND RELEVANCE

PCL guidelines should be viewed within the context of the data limitations on which they are based. PCL subtype-specific guidelines on surveillance and treatment are needed. In the future, the integration of cyst-specific genomic analysis, as well as evolutions in advanced diagnostic tools, such as cyst fluid next-generation sequencing and EUS-guided confocal laser endomicroscopy, may also better inform treatment guidelines. Owing to the current low-quality evidence on which many guidelines are based and the inherent morbidity of pancreas surgery, it is imperative that patients with PCLs are referred to institutions with advanced diagnostics and a multidisciplinary approach to patient surveillance and management.

Advances in the Diagnosis of Pancreatic Cystic Lesions

Pancreatic cystic lesions (PCLs) are a heterogenous group of lesions ranging from benign to malignant. There has been an increase in PCLs prevalence in recent years, mostly due to advances in imaging techniques, increased awareness of their existence and population aging. Reliable discrimination between neoplastic and non-neoplastic cystic lesions is paramount to ensuring adequate treatment and follow-up. Although conventional diagnostic techniques such as ultrasound (US), magnetic resonance imaging (MRI) and computer tomography (CT) can easily identify these lesions, assessing the risk of malignancy is limited. Endoscopic ultrasound (EUS) is superior to cross-sectional imaging in identifying potentially malignant lesions due to its high resolution and better imaging characteristics, and the advantage of allowing for cyst fluid sampling via fine-needle aspiration (FNA). More complex testing, such as cytological and histopathological analysis and biochemical and molecular testing of the aspirated fluid, can ensure an accurate diagnosis.

Intracystic Glucose Levels Appear Useful for Diagnosis of Pancreatic Cystic Lesions: A Systematic Review and Meta-Analysis

BACKGROUND

Carcinoembryonic antigen (CEA) in the pancreatic cystic fluid is the most important biomarker for differentiating mucinous from non-mucinous pancreatic cystic lesions (PCLs). However, recent studies have shown that glucose levels in pancreatic cystic fluid can discriminate mucinous from non-mucinous cysts.

AIMS

To perform a meta-analysis to determine the utility of intracystic fluid glucose of pancreatic mucinous cysts compared with intracystic CEA.

METHODS

We conducted a systematic review of the literature in the PubMed, OVID Medline, and Cochrane databases. This meta-analysis considers studies published up to October 2020.

RESULTS

Six studies comprising 506 patients were selected; 61.2% of the population was female. Of the 480 PCLs, 287 (59.7%) were mucinous. Pooled sensitivity and specificity of cystic fluid glucose levels for mucinous PCLs were 91% and 85%, respectively. The positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 6.33 and 0.11, respectively. Pooled diagnostic odds ratio (DOR) was 60.94. The pooled area under the summary receiver operating characteristic (SROC) curve was 0.959. Pooled sensitivity and specificity of pancreatic cystic fluid CEA levels were 61% and 93%. The PLR and NLR were 8.51 and 0.40, respectively. Pooled DOR was 23.52, and the pooled area under the SROC curve was 0.861.

CONCLUSION

Glucose has become a useful method and appears to be better than CEA for differentiating between mucinous PCLs and non-mucinous PCLs. We suggest that the analysis of glucose in PCLs be routinely performed for the differential diagnosis of these lesions.

Needle-based confocal laser endomicroscopy for diagnosis of pancreatic cystic lesions: a meta-analysis

BACKGROUND AND AIM

The role of needle-based confocal laser endomicroscopy (nCLE) in the diagnosis of pancreatic cystic lesions (PCLs) remains controversial. This study aimed to systematically evaluate the diagnostic accuracy and adverse effects of nCLE in the detection of pathological subtypes in patients with PCLs.

MATERIAL AND METHODS

We conducted a comprehensive literature search using MEDLINE, EMBASE, and Cochrane for identifying studies that reported the use of nCLE for PCLs diagnosis (dated prior to 10 October 2020). Studies with a sample size >10 were included. We used the QUADAS-2 criteria for quality evaluation. We first extracted the diagnostic rates and the information on adverse events (AEs) from the studies; then used STATA15.0 to calculate the variables, draw forest plots and summary receiver operating characteristic (SROC) curves; and finally, we completed subgroup analyses to explore the heterogeneity.

RESULTS

Overall, 299 article titles were identified after an initial search, and ten studies with 547 individuals with PCLs were included in the analysis. The pooled sensitivity, specificity, positive likelihood ratio, and pooled negative likelihood ratio of nCLE in detecting gastric disorders were 90%, 96%, 20.4, and 0.11, respectively. The pooled sensitivity and specificity showed a substantial heterogeneity. An ROC curve was constructed with an area under the curve (AUC) of 0.94. The overall AEs rate of pancreatitis was 2.7%.

CONCLUSIONS

We showed that nCLE had a relatively high sensitivity and specificity for diagnosing PCLs with a relatively low rate of AEs occurring. We suggest that nCLE has good diagnostic accuracy for PCLs.