Protein biomarkers in pancreatic juice and serum for identification of pancreatic cancer

Multimodal Pancreatic Cancer Detection Using Methylated DNA Biomarkers in Pancreatic Juice and Plasma CA 19-9: A Prospective Multicenter Study

BACKGROUND AND AIMS

In previous studies, methylated DNA markers (MDMs) have been identified in pancreatic juice (PJ) for detecting pancreatic ductal adenocarcinoma (PDAC). In this prospective multicenter study, the sensitivity and specificity characteristics of this panel of PJ-MDMs was evaluated standalone and in combination with plasma carbohydrate antigen 19-9 (CA 19-9).

METHODS

Paired PJ and plasma were assayed from 88 biopsy-proven treatment-naïve PDAC cases and 134 controls (53 with normal pancreas, 23 with chronic pancreatitis [CP], 58 with intraductal papillary mucinous neoplasm). Bisulfite-converted DNA from buffered PJ was analyzed using long-probe quantitative amplified signal assay targeting 14 MDMs (NDRG4, BMP3, TBX15, C13orf18, PRKCB, CLEC11A, CD1D, ELMO1, IGF2BP1, RYR2, ADCY1, FER1L4, EMX1, and LRRC4) and a reference gene (methylated B3GALT6). Logistic regression was used to fit the previously identified 3-MDM PJ panel (FER1L4, C13orf18, and BMP3). Discrimination accuracy was summarized using area under the receiver-operating characteristic curve (AUROC) with corresponding 95% confidence interval (CI).

RESULTS

Methylated FER1L4 had the highest individual AUROC of 0.83 (95% CI, 0.78-0.89). The AUROC for the 3-MDM PJ + plasma CA 19-9 model (0.95; 95% CI, 0.92-0.98) was higher than both the 3-MDM PJ panel (0.87; 95% CI, 0.82-0.92)) and plasma CA 19-9 alone (0.91; 95% CI, 0.87-0.96) (P = .0002 and .0135, respectively). At a specificity of 88% (95% CI, 81%-93%), the sensitivity of this model was 89% (95% CI, 80%-94%) for all PDAC stages and 83% (95% CI, 64%-94%) for stage I/II PDAC.

CONCLUSIONS

A panel combining PJ-MDMs and plasma CA 19-9 discriminates PDAC from both healthy and disease control groups with high accuracy. This provides support for combining PJ and blood-based biomarkers for enhancing diagnostic sensitivity and successful early PDAC detection.

Recommendations, evidence and sustainability of screening for pancreatic cancer in high-risk individuals

Pancreatic cancer is a highly lethal malignancy and is predicted to become the second leading cause of cancer-related deaths by 2030. Early detection significantly improves outcomes, but general population screening remains infeasible due to the low prevalence of the disease and lack of specific biomarkers. This review evaluates current recommendations for pancreatic cancer surveillance in high-risk individuals, synthesises evidence from recent studies and explores the sustainability of current imaging-based surveillance programmes. Challenges such as overdiagnosis, economic feasibility and disparities in access highlight the need for targeted, cost-effective strategies. Collaborative initiatives and consortia are needed to advance biomarker research and refine risk stratification. By integrating evidence-based recommendations with sustainable approaches, this review outlines pathways to improve early detection and reduce mortality from pancreatic cancer.

Pancreatic cancer surveillance: Risk stratification of individuals with a germline CDKN2A pathogenic variant

BACKGROUND

Individuals carrying a germline CDKN2A pathogenic variant (PV) are at a high risk of developing pancreatic ductal adenocarcinoma. Risk stratification could allow tailored surveillance.

OBJECTIVE

To develop a Fine-Gray prediction model for the risk of PDAC in carriers of a CDKN2A PV.

METHODS

Data from two large Dutch pancreatic cancer surveillance programs were used. A limited set of predictor variables were selected bsased on previous literature and the clinical expertise of the study group.

RESULTS

A total of 506 CDKN2A PV carriers were included, among whom we showed a substantial lifetime risk of PDAC (23%). The model identifies having a first-degree relative with PDAC (B = 0.7256) and a history of smoking (B = 0.4776) as significant risk factors. However, the model shows limited discrimination (c-statistic 0.64) and calibration.

CONCLUSION

Our study highlights the high lifetime risk of PDAC in carriers of a CDKN2A PV. While identifying significant risk factors such as family history of PDAC and smoking, our prediction model shows limited precision, highlighting the need for additional factors such as biomarkers to improve its clinical utility for tailored surveillance of high-risk individuals.

Bead-based spontaneous Raman codes for multiplex immunoassay

In the immunoassay process, for fulfilling the need to identify multiple analytes in a small amount of complex sample matrix, it is desirable to develop highly efficient and specific multiplex suspension array technology. Raman coding strategy offers an attractive solution to code the suspension arrays by simply combing narrow spectral bands with stable signal intensities through solid-phase synthesis on the resin beads. Based on this strategy, we report the bead-based spontaneous Raman codes for multiplex immunoassay. The study resulted in superior selectivity of the Raman-encoded beads for binding with single and multiple analytes, respectively. With the use of mixed types of Raman-encoded immunoassay beads, multiple targets in small amounts of samples were identified rapidly and accurately. By confirming the feasibility of bead-based spontaneous Raman codes for multiplex immunoassay, we anticipate this novel technology to be widely applied in the near future.

The role of endoscopic ultrasound in the detection of pancreatic lesions in high-risk individuals

Individuals at high risk of developing pancreatic ductal adenocarcinoma are eligible for surveillance within research programs. These programs employ periodic imaging in the form of magnetic resonance imaging/magnetic resonance cholangiopancreatography or endoscopic ultrasound for the detection of early cancer or high-grade precursor lesions. This narrative review discusses the role of endoscopic ultrasound within these surveillance programs. It details its overall strengths and limitations, yield, burden on patients, and how it compares to magnetic resonance imaging. Finally, recommendations are given when and how to incorporate endoscopic ultrasound in the surveillance of high-risk individuals.

Aspects and outcomes of surveillance for individuals at high-risk of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related deaths and is associated with a poor prognosis. The majority of these cancers are detected at a late stage, contributing to the bad prognosis. This underscores the need for novel, enhanced early detection strategies to improve the outcomes. While population-based screening is not recommended due to the relatively low incidence of PDAC, surveillance is recommended for individuals at high risk for PDAC due to their increased incidence of the disease. However, the outcomes of pancreatic cancer surveillance in high-risk individuals are not sorted out yet. In this review, we will address the identification of individuals at high risk for PDAC, discuss the objectives and targets of surveillance, outline how surveillance programs are organized, summarize the outcomes of high-risk individuals undergoing pancreatic cancer surveillance, and conclude with a future perspective on pancreatic cancer surveillance and novel developments.

Neutrophil Gelatinase-Associated Lipocalin for the Differentiation of Mucinous Pancreatic Cystic Lesions

Undetermined pancreatic cystic lesion (PCL) differentiation benefits from endoscopic ultrasound (EUS) based on morphology and cyst fluid analysis, but room for new biomarkers exists. Our aim was to assess the intracystic and serum diagnostic value of neutrophil gelatinase-associated lipocalin (Ngal) and interleukin 1 beta (IL-1β) for differentiation of PCLs. This prospective study included patients from one tertiary hospital, evaluated between April 2018 and May 2020. EUS fine-needle aspiration or pancreatic pseudocysts drainage was the source of PCL intracystic liquid. The final diagnosis was based on surgery or EUS results (morphology, cytology, glucose, and CEA-carcinoembryogenic antigen). The intracystic samples were tested for Ngal, IL-1β, glucose, and CEA, and serum for Ngal and IL-1β. We evaluated 63 cysts, 33 pseudocysts, and 30 non-inflammatory cysts. The diagnostic sensitivity and specificity for mucinous PCL was 70.8% and 92.3% for intracystic Ngal (cut-off: 500-800 ng/dL), without correlation with serum Ngal, no matter the inclusion of infected pseudocysts. After exclusion of infected pseudocysts, the sensitivity and specificity for glucose were 87% and 75%, respectively, and for CEA, they were 87.1%, and 96.8%, respectively. Intracystic Ngal shows promise in differentiating mucinous PCLs, but researchers need to conduct further studies to confirm its effectiveness. Intracystic IL-1β and serum Ngal made no diagnostic contribution.

Pancreatic Cancer-Secreted Proteins: Targeting Their Functions in Tumor Microenvironment

Pancreatic Ductal Adenocarcinoma (PDAC) is a ravaging disease with a poor prognosis, requiring a more detailed understanding of its biology to foster the development of effective therapies. The unsatisfactory results of treatments targeting cell proliferation and its related mechanisms suggest a shift in focus towards the inflammatory tumor microenvironment (TME). Here, we discuss the role of cancer-secreted proteins in the complex TME tumor-stroma crosstalk, shedding lights on druggable molecular targets for the development of innovative, safer and more efficient therapeutic strategies.

The additive value of CA19.9 monitoring in a pancreatic cyst surveillance program

BACKGROUND

Surveillance of pancreatic cysts focuses on the detection of (mostly morphologic) features warranting surgery. European guidelines consider elevated CA19.9 as a relative indication for surgery. We aimed to evaluate the role of CA19.9 monitoring for early detection and management in a cyst surveillance population.

METHODS

The PACYFIC-registry is a prospective collaboration that investigates the yield of pancreatic cyst surveillance performed at the discretion of the treating physician. We included participants for whom at least one serum CA19.9 value was determined by a minimum follow-up of 12 months.

RESULTS

Of 1865 PACYFIC participants, 685 met the inclusion criteria for this study (mean age 67 years, SD 10; 61% female). During a median follow-up of 25 months (IQR 24, 1966 visits), 29 participants developed high-grade dysplasia (HGD) or pancreatic cancer. At baseline, CA19.9 ranged from 1 to 591 kU/L (median 10 kU/L [IQR 14]), and was elevated (≥37 kU/L) in 64 participants (9%). During 191 of 1966 visits (10%), an elevated CA19.9 was detected, and these visits more often led to an intensified follow-up (42%) than those without an elevated CA19.9 (27%; p < 0.001). An elevated CA19.9 was the sole reason for surgery in five participants with benign disease (10%). The baseline CA19.9 value was (as continuous or dichotomous variable at the 37 kU/L threshold) not independently associated with HGD or pancreatic cancer development, whilst a CA19.9 of ≥ 133 kU/L was (HR 3.8, 95% CI 1.1-13, p = 0.03).

CONCLUSIONS

In this pancreatic cyst surveillance cohort, CA19.9 monitoring caused substantial harm by shortening surveillance intervals (and performance of unnecessary surgery). The current CA19.9 cutoff was not predictive of HGD and pancreatic cancer, whereas a higher cutoff may decrease false-positive values. The role of CA19.9 monitoring should be critically appraised prior to implementation in surveillance programs and guidelines.

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

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