Deleterious Germline Mutations Are a Risk Factor for Neoplastic Progression Among High-Risk Individuals Undergoing Pancreatic Surveillance

Familial Intraductal Papillary Mucinous Neoplasm Associated With the Germline MSH6 Missense Variant and Progression of Pancreatic cancer

OBJECTIVES

Intraductal papillary mucinous neoplasm (IPMN) in individuals with at least one first-degree relative with IPMN is defined as familial IPMN. However, few studies have reported on familial IPMN, its clinical characteristics, or the associated genetic factors.

MATERIALS AND METHODS

We report the case of a 58-year-old woman with multifocal IPMN and a mural nodule in the pancreatic body. The patient underwent a distal pancreatectomy and developed pancreatic head cancer 1 year and 6 months postoperatively. The patient had a family history of multifocal IPMN in her father. Therefore, a genetic predisposition to IPMN and pancreatic cancer was suspected. The patient was analyzed for germline variants, and the resected IPMN was subjected to immunohistochemical and somatic variant analyses.

RESULTS

Next-generation sequencing revealed a heterozygous germline missense variant in exon 5 of MSH6 (c.3197A>G; Tyr1066Cys). The pathogenicity of this variant of uncertain significance was suspected based on multiple in silico analyses, and the same MSH6 variant was identified in the patient's father's colonic adenoma. The mural nodule in the pancreatic body was pathologically diagnosed as a high-grade IPMN with ossification and somatic KRAS and PIK3CA variants.

CONCLUSIONS

This case revealed a possible genetic factor for familial IPMN development and presented interesting clinicopathological findings.

Germline Pathogenic Variants in Patients With Pancreatic and Periampullary Cancers

PURPOSE

Inherited cancer susceptibility is often not suspected in the absence of a significant cancer family history. Pathogenic germline variants in pancreatic cancer are well-studied, and routine genetic testing is recommended in the guidelines. However, data on rare periampullary cancers other than pancreatic cancer are insufficient. We compared the prevalence of germline susceptibility variants in patients with pancreatic cancer and nonpancreatic periampullary cancers.

MATERIALS AND METHODS

Six hundred and eight patients who had undergone pancreaticoduodenal resection at a tertiary referral hospital were studied, including 213 with pancreatic ductal adenocarcinoma, 172 with ampullary cancer, 154 with distal common bile duct cancer, and 69 with duodenal adenocarcinoma. Twenty cancer susceptibility and candidate susceptibility genes were sequenced, and variant interpretation was assessed by interrogating ClinVar and PubMed.

RESULTS

Pathogenic or likely pathogenic, moderate- to high-penetrant germline variants were identified in 46 patients (7.7%), including a similar percentage of patients with pancreatic (8.5%) and nonpancreatic periampullary cancer (7.1%). Low-penetrant variants were identified in an additional 11 patients (1.8%). Eighty-nine percent of the moderate- to high-penetrant variants involved the major cancer susceptibility genes BRCA2, ATM, BRCA1, CDKN2A, MSH2/MLH1, and PALB2; the remaining 11% involved other cancer susceptibility genes such as BRIP1, BAP1, and MSH6. Almost all pathogenic variant carriers had a family history of cancer.

CONCLUSION

Patients with pancreatic and nonpancreatic periampullary cancer have a similar prevalence of pathogenic cancer susceptibility variants. Germline susceptibility testing should be considered for patients with any periampullary cancer.

Biological functions of circRNA in regulating the hallmarks of gastrointestinal cancer (Review)

Circular RNA (circRNA) was first observed in the cytoplasm of eukaryotic cells in 1979, but it was not characterized in detail until 2012, when high‑throughput sequencing technology was more advanced and available. Consequently, the mechanism of circRNA formation and its biological function have been progressively elucidated by researchers. circRNA is abundant in eukaryotic cells and exhibits a certain degree of organization, timing and disease‑specificity. Additionally, it is poorly degradable, meeting the characteristics of an ideal clinical biomarker. In the present review, the recent research progress of circRNAs in digestive tract malignant tumors was primarily discussed. This included the roles, biological functions and clinical significance of circRNA, providing references for its research value and clinical potential in gastrointestinal cancer.

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.

Outcomes of a 3-Year Prospective Surveillance in Individuals at High Risk of Pancreatic Cancer

INTRODUCTION

Pancreatic cancer (PC) surveillance of high-risk individuals (HRI) is becoming more common worldwide, aiming at anticipating PC diagnosis at a preclinical stage. In 2015, the Italian Registry of Families at Risk of Pancreatic Cancer was created. We aimed to assess the prevalence and incidence of pancreatic findings, oncological outcomes, and harms 7 years after the Italian Registry of Families at Risk of Pancreatic Cancer inception, focusing on individuals with at least a 3-year follow-up or developing events before.

METHODS

HRI (subjects with a family history or mutation carriers with/without a family history were enrolled in 18 centers). They underwent annual magnetic resonance with cholangiopancreatography or endoscopic ultrasound (NCT04095195).

RESULTS

During the study period (June 2015-September 2022), 679 individuals were enrolled. Of these, 524 (77.2%) underwent at least baseline imaging, and 156 (29.8%) with at least a 3-year follow-up or pancreatic malignancy/premalignancy-related events, and represented the study population. The median age was 51 (interquartile range 16) years. Familial PC cases accounted for 81.4% of HRI and individuals with pathogenic variant for 18.6%. Malignant (n = 8) and premalignant (1 PanIN3) lesions were found in 9 individuals. Five of these 8 cases occurred in pathogenic variant carriers, 4 in familial PC cases (2 tested negative at germline testing and 2 others were not tested). Three of the 8 PC were stage I. Five of the 8 PC were resectable, 3 Stage I, all advanced cases being prevalent. The 1-, 2-, and 3-year cumulative hazard of PC was 1.7%, 2.5%, and 3%, respectively. Median overall and disease-free survival of patients with resected PC were 18 and 12 months (95% CI not computable). Considering HRI who underwent baseline imaging, 6 pancreatic neuroendocrine neoplasms (1 resected) and 1 low-yield surgery (low-grade mixed-intraductal papillary mucinous neoplasm) were also reported.

DISCUSSION

PC surveillance in a fully public health care system is feasible and safe, and leads to early PC or premalignant lesions diagnoses, mostly at baseline but also over time.

Protein biomarkers and alternatively methylated cell-free DNA detect early stage pancreatic cancer

OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) is commonly diagnosed at an advanced stage. Liquid biopsy approaches may facilitate detection of early stage PDAC when curative treatments can be employed.

DESIGN

To assess circulating marker discrimination in training, testing and validation patient cohorts (total n=426 patients), plasma markers were measured among PDAC cases and patients with chronic pancreatitis, colorectal cancer (CRC), and healthy controls. Using CA19-9 as an anchor marker, measurements were made of two protein markers (TIMP1, LRG1) and cell-free DNA (cfDNA) pancreas-specific methylation at 9 loci encompassing 61 CpG sites.

RESULTS

Comparative methylome analysis identified nine loci that were differentially methylated in exocrine pancreas DNA. In the training set (n=124 patients), cfDNA methylation markers distinguished PDAC from healthy and CRC controls. In the testing set of 86 early stage PDAC and 86 matched healthy controls, CA19-9 had an area under the receiver operating characteristic curve (AUC) of 0.88 (95% CI 0.83 to 0.94), which was increased by adding TIMP1 (AUC 0.92; 95% CI 0.88 to 0.96; p=0.06), LRG1 (AUC 0.92; 95% CI 0.88 to 0.96; p=0.02) or exocrine pancreas-specific cfDNA methylation markers at nine loci (AUC 0.92; 95% CI 0.88 to 0.96; p=0.02). In the validation set of 40 early stage PDAC and 40 matched healthy controls, a combined panel including CA19-9, TIMP1 and a 9-loci cfDNA methylation panel had greater discrimination (AUC 0.86, 95% CI 0.77 to 0.95) than CA19-9 alone (AUC 0.82; 95% CI 0.72 to 0.92).

CONCLUSION

A combined panel of circulating markers including proteins and methylated cfDNA increased discrimination compared with CA19-9 alone for early stage PDAC.

SMAD4 loss predicts worse overall and distant metastasis-free survival in patients with resected pancreatic adenocarcinoma

BACKGROUND

In select patients, pancreatic adenocarcinoma remains a local disease, yet there are no validated biomarkers to predict this behavior and who may benefit from aggressive local treatments. This study sought to determine if SMAD4 (mothers against decapentaplegic homolog 4) messenger RNA-sequencing (RNA-seq) expression is a robust method for predicting overall survival (OS) and distant metastasis-free survival (DMFS) in patients with resected pancreatic adenocarcinoma.

METHODS

Utilizing The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC), 322 patients with resected stage I-III pancreatic adenocarcinoma were identified. In TCGA, multivariable proportional hazards models were used to determine the association of SMAD4 genomic aberrations and RNA-seq expression with OS and DMFS. In the ICGC, analysis sought to confirm the predictive performance of RNA-seq via multivariable models and receiver operator characteristic curves.

RESULTS

In TCGA, the presence of SMAD4 genomic aberrations was associated with worse OS (hazard ratio [HR], 1.55; 95% CI, 1.00-2.40; p = .048) but not DMFS (HR, 1.33; 95% CI, .87-2.03; p = .19). Low SMAD4 RNA-seq expression was associated with worse OS (HR, 1.83; 95% CI, 1.17-2.86; p = .008) and DMFS (HR, 1.70; 95% CI, 1.14-2.54; p = .009). In the ICGC, increased SMAD4 RNA-seq expression correlated with improved OS (area under the curve [AUC], .92; 95% CI, .86-.94) and DMFS (AUC, .84; 95% CI, .82-.87).

CONCLUSIONS

In patients with resected pancreatic adenocarcinoma, SMAD4 genomic aberrations are associated with worse OS but do not predict for DMFS. Increased SMAD4 RNA-seq expression is associated with improved OS and DMFS in patients with resected pancreatic adenocarcinoma. This reproducible finding suggests SMAD4 RNA-seq expression may be a useful marker to predict metastatic spread.

Biological and clinical implications of early-onset cancers: A unique subtype

In recent years, the incidence of cancers is continuously increasing in young adults. Early-onset cancer (EOC) is usually defined as patients with cancers under the age of 50, and may represent a unique subgroup due to its special disease features. Overall, EOCs often initiate at a young age, present as a better physical performance but high degree of malignancy. EOCs also share common epidemiological and hereditary risk factors. In this review, we discuss several representative EOCs which were well studied previously. By revealing their clinical and molecular similarities and differences, we consider the group of EOCs as a unique subtype compared to ordinary cancers. In consideration of EOC as a rising threat to human health, more researches on molecular mechanisms, and large-scale, prospective clinical trials should be carried out to further translate into improved outcomes.

Are All Cysts Created Equal?: Pancreatic Cystic Neoplasms in Patients with Familial or Genetic Risk Factors for Pancreatic Cancer

Pancreatic cystic lesions (PCLs) have become more prevalent over time, particularly in asymptomatic individuals. Current screening guidelines for incidental PCLs offer a unified approach to surveillance and management, predicated on "worrisome features." Although PCLs are common in the general population, their prevalence may be higher in high-risk individuals (HRI, unaffected patients with specific familial and/or genetic risk factors). As more PCLs are diagnosed and more HRI identified, it is important to promote research that bridges data gaps and introduces nuance to risk assessment tools, ensuring tailoring of guidelines to the needs of HRI with varying pancreatic cancer risk factors.

Characteristics of familial pancreatic cancer families with additional colorectal carcinoma

Familial pancreatic cancer (FPC) is a rare hereditary tumor entity with broad phenotypic heterogeneity, including colorectal carcinoma (CRC) in some families. The underlying factors for this co-occurrence are still not well evaluated. FPC families in the National Case Collection of Familial Pancreatic Cancer with an additional occurrence of CRC were analyzed regarding the phenotype, genotype and recommendation for a clinical screening program. The total cohort of 272 FPC families included 30 (11%) families with at least one CRC case. The proportion of affected family members with PDAC was 16.1% (73/451) compared to 9.3% of family members with CRC (42/451, p < 0.01). Females were affected with PDAC in 49% (36/73) and CRC in 38% (16/42). The median age of PDAC was 63 compared to 66 years in CRC, whereas 8 (26.6%) of families had an early onset of PDAC and 2 (6.7%) of CRC. Seventeen families had 2 or more affected generations with PDAC and 6 families with CRC. Eleven (9.6%) of affected patients had both PDAC and CRC. Potentially causative germline mutations (2 ATM, 1 CDKN2a, 1 MLH1, 1 PALB2) were detected in 5 of 18 (27.7%) analyzed cases. These findings provide a step forward to include the phenotypic and genotypic characteristics of FPC-CRC families for the genetic counseling and management of these families. Nevertheless, results need to be verified in a larger patient cohort beforehand.

A non-mutated TROP2 fingerprint in cancer genetics

The advent of high throughput DNA sequencing is providing massive amounts of tumor-associated mutation data. Implicit in these analyses is the assumption that, by acquiring a series of hallmark changes, normal cells evolve along a neoplastic path. However, the lack of correlation between cancer risk and global exposure to mutagenic factors provides arguments against this model. This suggested that additional, non-mutagenic factors are at work in cancer development. A candidate determinant is TROP2, that stands out for its expression in the majority of solid tumors in human, for its impact on the prognosis of most solid cancers and for its role as driver of cancer growth and metastatic diffusion, through overexpression as a wild-type form. The Trop-2 signaling network encompasses CREB1, Jun, NF-κB, Rb, STAT1 and STAT3, through induction of cyclin D1 and MAPK/ERK. Notably, Trop-2-driven pathways vastly overlap with those activated by most functionally relevant/most frequently mutated RAS and TP53, and are co-expressed in a large fraction of individual tumor cases, suggesting functional overlap. Mutated Ras was shown to synergize with the TROP2-CYCLIND1 mRNA chimera in transforming primary cells into tumorigenic ones. Genomic loss of TROP2 was found to promote carcinogenesis in squamous cell carcinomas through modulation of Src and mutated Ras pathways. DNA methylation and TP53 status were shown to cause genome instability and TROP gene amplification, together with Trop-2 protein overexpression. These findings suggest that mutagenic and the TROP2 non-mutagenic pathways deeply intertwine in driving transformed cell growth and malignant progression of solid cancers.

Novel Insights Into Immunohistochemical Analysis For Acinar Cell Neoplasm of The Pancreas: Carboxypeptidase A2, Carboxypeptidase A1, and Glycoprotein 2

Acinar cell carcinoma (ACC) is a rare and highly malignant pancreatic tumor. Owing to histologic similarity, ACC is often difficult to distinguish from other solid medullary pancreatic tumors, particularly neuroendocrine neoplasm (NEN) and intraductal tubulopapillary neoplasm (ITPN). We aimed to identify new immunohistochemical markers commonly expressed in tumor cells with acinar cell differentiation and useful for both surgical and small biopsy specimens. Candidate molecules exclusively expressed in neoplastic or non-neoplastic acinar cells in pancreatic tissues with specific and available antibodies suitable for immunohistochemistry were selected. We selected carboxypeptidase A1 (CPA1), carboxypeptidase A2 (CPA2), and glycoprotein 2 (GP2), which were expressed in 100%, 100%, and 96% of cases, respectively, in ACC (n=27) or neoplasia with acinar cell differentiation, including mixed acinar-neuroendocrine carcinoma (n=9), mixed acinar-ductal carcinoma (n=3), pancreatoblastoma (n=4), and acinar cystic transformation (n=2), in the cytoplasm of tumor cells with a granular pattern. Both CPA2 and CPA1 were not expressed in any other tumors without acinar cell differentiation, including NEN (n=44), pancreatic ductal adenocarcinoma (n=44), and ITPN (n=4). GP2 was not expressed in these tumors except in rare cases, including 14% of NEN, 15% of intraductal papillary-mucinous neoplasm, 25% of intraductal oncocytic papillary neoplasm, 25% of ITPN, and 7% of pancreatic ductal adenocarcinoma, wherein a small proportion of tumor cells expressed GP2 in their apical cell membrane. NEN cases also showed cytoplasmic GP2 expression. Therefore, CPA2, CPA1, and potentially GP2 may act as ACC markers.

TP53 Gain-of-Function and Non-Gain-of-Function Mutations Are Associated With Differential Prognosis in Advanced Pancreatic Ductal Adenocarcinoma

PURPOSE

To examine the impact of TP53 gain-of-function (GOF) and non-GOF mutations on prognosis of advanced pancreatic ductal adenocarcinoma (PDAC) among patients with KRAS, CDKN2A, and SMAD4 comutations.

METHODS

This cohort included patients with locally advanced, recurrent, and de novo metastatic PDAC with next-generation sequencing performed from November 2017 to May 2022. We defined R175H, R248W, R248Q, R249S, R273H, R273L, and R282W as GOF and all other p53 mutations (mutp53) as non-GOF. We used Cox regression modeling to examine the association between GOF and non-GOF mutp53 and overall survival (OS), adjusting for demographics, performance status, Charlson comorbidity index, receipt of chemotherapy, and KRAS, CDKN2A, and SMAD4 comutations.

RESULTS

Of 893 total eligible patients, 68.5% had tumors with mutp53, 90.1% had KRAS mutations (mutKRAS), 44.7% had CDKN2A mutations (mutCDKN2A), and 17.0% had SMAD4 mutations. Among patients with mutp53, 121 had GOF and 491 had non-GOF. GOF mutp53 was associated with worse OS than non-GOF mutp53 (hazard ratio [HR], 1.27; 95% CI, 1.02 to 1.59) and wild-type p53 (wtp53; HR, 1.24; 95% CI, 0.98 to 1.57), whereas non-GOF was not associated with worse OS than wtp53 (HR, 0.95; 95% CI, 0.80 to 1.13). In addition, mutKRAS was associated with worse OS than wild-type KRAS in patients with mutCDKN2A (HR, 1.57; 95% CI, 0.88 to 2.80) but not in patients with wild-type CDKN2A (HR, 1.03; 95% CI, 0.76 to 1.39).

CONCLUSION

GOF and non-GOF mutp53 were associated with differential prognosis in advanced PDAC. The adverse effect of mutKRAS on OS appeared to be primarily driven by patients with mutCDKN2A. Our results provide new insight that could be helpful for prognostic stratification in clinical practice and for aiding future clinical trial designs.

Diagnostic value of combining preoperative inflammatory markers ratios with CA199 for patients with early-stage pancreatic cancer

BACKGROUND

An early diagnosis of pancreatic cancer (PC) is extremely difficult because of the lack of sensitive liquid biopsy methods and effective biomarkers. We attempted to evaluate whether circulating inflammatory marker could complement CA199 for the detection of early-stage PC.

METHODS

We enrolled 430 patients with early-stage PC, 287 patients with other pancreatic tumors (OPT), and 401 healthy controls (HC). The patients and HC were randomly divided into a training set (n = 872) and two testing sets (n₁ = 218, n₂ = 28). The receiver operating characteristic (ROC) curves were investigated to evaluate the diagnostic performance of circulating inflammatory markers ratios, CA199, and combinations of the markers ratios in the training set, which would then be validated in the two testing sets.

RESULTS

Circulating fibrinogen, neutrophils, and monocytes in patients with PC were significantly higher while circulating albumin, prealbumin, lymphocytes, and platelets of patients with PC were significantly lower compared to those of HC and OPT (all P < 0.05). The fibrinogen-to-albumin (FAR), fibrinogen-to-prealbumin (FPR), neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR), monocyte-to-lymphocyte (MLR), and fibrinogen-to-lymphocyte (FLR) ratios were significantly higher while the prognostic nutrition index values (PNI) were lower in patients with PC than in HC and OPT (all P < 0.05). Combining the FAR, FPR, and FLR with CA199 exhibited the best diagnostic value for distinguishing patients with early-stage PC from HC with an area under the curve (AUC) of 0.964, and for distinguishing patients with early-stage PC from OPT with an AUC of 0.924 in the training sets. In the testing set, compared with HC, the combination markers had powerful efficiency for PC with an AUC 0.947 and AUC 0.942 when comparing PC with OPT. The AUC was 0.915 for the combination of CA199, FAR, FPR, and FLR for differentiating between patients with pancreatic head cancer (PHC) and other pancreatic head tumors (OPHT), and 0.894 for differentiating between patients with pancreatic body and tail cancer (PBTC) and other pancreatic body and tail tumors (OPBTT).

CONCLUSION

A combination of FAR, FPR, FLR, and CA199 may serve as a potential non-invasive biomarker for differentiating early-stage PC from HC and OPT, especially early-stage PHC.

Pancreatic Cancer: Changing Epidemiology and New Approaches to Risk Assessment, Early Detection, and Prevention

Pancreatic cancer usually results in poor survival with limited options for treatment, as most affected individuals present with advanced disease. Early detection of preinvasive pancreatic neoplasia and identifying molecular therapeutic targets provide opportunities for extending survival. Although screening for pancreatic cancer is currently not recommended for the general population, emerging evidence indicates that pancreatic surveillance can improve outcomes for individuals in certain high-risk groups. Changes in the epidemiology of pancreatic cancer, experience from pancreatic surveillance, and discovery of novel biomarkers provide a roadmap for new strategies for pancreatic cancer risk assessment, early detection, and prevention.

Screening for pancreatic cancer has the potential to save lives, but is it practical?

INTRODUCTION

Most patients with pancreatic cancer present with advanced stage, incurable disease. However, patients with high-grade precancerous lesions and many patients with low-stage disease can be cured with surgery, suggesting that early detection has the potential to improve survival. While serum CA19.9 has been a long-standing biomarker used for pancreatic cancer disease monitoring, its low sensitivity and poor specificity have driven investigators to hunt for better diagnostic markers.

AREAS COVERED

This review will cover recent advances in genetics, proteomics, imaging, and artificial intelligence, which offer opportunities for the early detection of curable pancreatic neoplasms.

EXPERT OPINION

From exosomes, to circulating tumor DNA, to subtle changes on imaging, we know much more now about the biology and clinical manifestations of early pancreatic neoplasia than we did just five years ago. The overriding challenge, however, remains the development of a practical approach to screen for a relatively rare, but deadly, disease that is often treated with complex surgery. It is our hope that future advances will bring us closer to an effective and financially sound approach for the early detection of pancreatic cancer and its precursors.

Novel p.G250A Mutation Associated with Chronic Pancreatitis Highlights Misfolding-Prone Region in Carboxypeptidase A1 (CPA1)

Inborn mutations in the digestive protease carboxypeptidase A1 (CPA1) gene may be associated with hereditary and idiopathic chronic pancreatitis (CP). Pathogenic mutations, such as p.N256K, cause intracellular retention and reduced secretion of CPA1, accompanied by endoplasmic reticulum (ER) stress, suggesting that mutation-induced misfolding underlies the phenotype. Here, we report the novel p.G250A CPA1 mutation found in a young patient with CP. Functional properties of the p.G250A mutation were identical to those of the p.N256K mutation, confirming its pathogenic nature. We noted that both mutations are in a catalytically important loop of CPA1 that is stabilized by the Cys248-Cys271 disulfide bond. Mutation of either or both Cys residues to Ala resulted in misfolding, as judged by the loss of CPA1 secretion and intracellular retention. We re-analyzed seven previously reported CPA1 mutations that affect this loop and found that all exhibited reduced secretion and caused ER stress of varying degrees. The magnitude of ER stress was proportional to the secretion defect. Replacing the naturally occurring mutations with Ala (e.g., p.V251A for p.V251M) restored secretion, with the notable exception of p.N256A. We conclude that the disulfide-stabilized loop of CPA1 is prone to mutation-induced misfolding, in most cases due to the disruptive nature of the newly introduced side chain. We propose that disease-causing CPA1 mutations exhibit abolished or markedly reduced secretion with pronounced ER stress, whereas CPA1 mutations with milder misfolding phenotypes may be associated with lower disease risk or may not be pathogenic at all.

Concordance of EUS and MRI/MRCP findings among high-risk individuals undergoing pancreatic cancer screening

BACKGROUND/OBJECTIVES

Surveillance with endoscopic ultrasonography (EUS) and MRI/magnetic retrograde cholangiopancreatography (MRCP) is recommended for individuals at high risk for pancreatic cancer. We sought to characterize the findings of these surveillance exams and define the level of concordance between these two modalities.

METHODS

173 asymptomatic high-risk individuals (HRIs) meeting criteria for pancreatic cancer surveillance underwent EUS, MRI/MRCP, or both between 2008 and 2021. Clinical records were reviewed in all cases.

RESULTS

HRIs underwent an average of 3.6 ± 3.2 surveillance exams over a period of 3.3 ± 3.5 years. Abnormalities including intraductal papillary mucinous neoplasms (IPMNs), solid lesions, and parenchymal irregularities were identified in 50.9% (n = 88). Four of these abnormalities (2.3%) had worrisome features, defined by cyst size, thickened/enhancing cyst walls, rapid growth rate, or change in main pancreatic duct diameter. All four worrisome lesions were seen on both MRI/MRCP and EUS. No pancreatic cancers were detected. Baseline EUS and MRI/MRCP exams were compared in 106 patients for concordance, and most (n = 66, 62.3%) were concordant. High levels of concordance were specifically observed for a dilated main pancreatic duct (p < 0.01) and cystic lesions >5 mm (p = 0.01). Among discordant cases, most (30/40; 75%) involved abnormal tissue heterogeneity seen primarily on EUS. None of these discordant lesions ultimately developed worrisome features.

CONCLUSIONS

Worrisome pancreatic lesions were uncommon in our high-risk pancreatic cancer population and were detected by both EUS and MRI/MRCP. There was mild discordance with respect to less worrisome findings, but these discrepancies were not associated with any adverse clinical outcomes.

The Multicenter Cancer of Pancreas Screening Study: Impact on Stage and Survival

PURPOSE

To report pancreas surveillance outcomes of high-risk individuals within the multicenter Cancer of Pancreas Screening-5 (CAPS5) study and to update outcomes of patients enrolled in prior CAPS studies.

METHODS

Individuals recommended for pancreas surveillance were prospectively enrolled into one of eight CAPS5 study centers between 2014 and 2021. The primary end point was the stage distribution of pancreatic ductal adenocarcinoma (PDAC) detected (stage I v higher-stage). Overall survival was determined using the Kaplan-Meier method.

RESULTS

Of 1,461 high-risk individuals enrolled into CAPS5, 48.5% had a pathogenic variant in a PDAC-susceptibility gene. Ten patients were diagnosed with PDAC, one of whom was diagnosed with metastatic PDAC 4 years after dropping out of surveillance. Of the remaining nine, seven (77.8%) had a stage I PDAC (by surgical pathology) detected during surveillance; one had stage II, and one had stage III disease. Seven of these nine patients with PDAC were alive after a median follow-up of 2.6 years. Eight additional patients underwent surgical resection for worrisome lesions; three had high-grade and five had low-grade dysplasia in their resected specimens. In the entire CAPS cohort (CAPS1-5 studies, 1,731 patients), 26 PDAC cases have been diagnosed, 19 within surveillance, 57.9% of whom had stage I and 5.2% had stage IV disease. By contrast, six of the seven PDACs (85.7%) detected outside surveillance were stage IV. Five-year survival to date of the patients with a screen-detected PDAC is 73.3%, and median overall survival is 9.8 years, compared with 1.5 years for patients diagnosed with PDAC outside surveillance (hazard ratio [95% CI]; 0.13 [0.03 to 0.50], P = .003).

CONCLUSION

Most pancreatic cancers diagnosed within the CAPS high-risk cohort in the recent years have had stage I disease with long-term survival.

Serum Carboxypeptidase Activity and Genotype-Stratified CA19-9 to Detect Early-Stage Pancreatic Cancer

BACKGROUND AND AIMS

Serum diagnostic markers of early-stage pancreatic ductal adenocarcinoma (PDAC) are needed, especially for stage I disease. As tumors grow and cause pancreatic atrophy, markers derived from pancreatic parenchyma such as serum carboxypeptidase A (CPA) activity lose diagnostic performance. We evaluated, with CA19-9, serum CPA as a marker of early pancreatic cancer.

METHODS

Serum CPA activity levels were measured in 345 controls undergoing pancreatic surveillance, divided into 2 sets, set 1 being used to establish a reference range. Variants within the CPA1 locus were sought for their association with pancreatic CPA1 expression to determine if such variants associated with serum CPA levels. A total of 190 patients with resectable PDAC were evaluated.

RESULTS

Among controls, those having 1 or more minor alleles of CPA1 variants rs6955723 or rs2284682 had significantly higher serum CPA levels than did those without (P = .001). None of the PDAC cases with pancreatic atrophy had an elevated CPA. Among 122 PDAC cases without atrophy, defining serum CPA diagnostic cutoffs by a subject's CPA1 variants yielded a diagnostic sensitivity of 18% at 99% specificity (95% confidence interval [CI], 11.7-26) (vs 11.1% sensitivity using a uniform diagnostic cutoff); combining CPA with variant-stratified CA19-9 yielded a sensitivity of 68.0% (95% CI, 59.0-76.2) vs 63.1% (95% CI, 53.9- 71.7) for CA19-9 alone; and among stage I PDAC cases, diagnostic sensitivity was 51.9% (95% CI, 31.9-71.3) vs 37.0% (95% CI, 19.4-57.6) for CA19-9 alone. In the validation control set, the variant-stratified diagnostic cutoff yielded a specificity of 98.2%.

CONCLUSION

Serum CPA activity has diagnostic utility before the emergence of pancreatic atrophy as a marker of localized PDAC, including stage I disease.

Familial Pancreatic Cancer

Individuals at increased risk of developing pancreatic cancer, including those with a significant family history of the disease and those with pancreatic cancer susceptibility gene variants, can benefit from pancreas surveillance. Most pancreatic cancers diagnosed during surveillance are early-stage and such patients can achieve long-term survival. Determining who should undergo pancreas surveillance is still a work-in-progress, but the main tools clinicians use to estimate an individual's risk of pancreatic cancer are patient's age, the extent of their family history of pancreatic cancer, and whether or not they have a pancreatic cancer susceptibility gene mutation.

Aberrant APOBEC3C expression induces characteristic genomic instability in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a well-known lethal and heterogeneous disease. Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC) is an important mutagenic driver that has seldom been investigated in PDAC. Therefore, this study investigated the significance of APOBEC3C in PDAC. First, cytosine deamination-associated mutation signatures were identified in the PDAC cohorts from TCGA and Fudan University Shanghai Cancer Center (FUSCC) datasets, and C > X-enriched kataegis regions were identified in the FUSCC cohort (12 to 27 counts per sample). Patients were stratified according to APOBEC3C expression, and high APOBEC3C expression was found to correlate with a higher motif enrichment score of 5’-CC-3’ and an elevated kataegis count within PCSK5 and NES genes. Second, we compared APOBEC expression in PDAC and normal pancreatic tissues and found that APOBEC3C was substantially upregulated in PDAC. APOBEC3C-overexpressing cell lines were generated to substantiate the effects of APOBEC3C on PDAC genome, including alterations in single-nucleotide variant (SNV) classes (higher proportion of C > T conversions) and the formation of kataegis regions (newly occurring kataegis regions detected in ACHE and MUC6 genes). Three different PDAC cohorts (FUSCC, TCGA, and QCMG) were analysed to evaluate the prognostic value of APOBEC3C, and APOBEC3C overexpression predicted shorter survival. Finally, the APOBEC3C overexpression correalted with the PDAC tumour microenvironment (TME) remodelling, APOBEC3C expression was associated with the invasion of CD4 + T lymphocytes and CD8 + T lymphocytes (cytotoxic T lymphocytes, CTLs), indicating enhanced immune activity and validating the practicality of APOBEC3C for guiding immunotherapy.

Is Biannual Surveillance for Pancreatic Cancer Sufficient in Individuals With Genetic Syndromes or Familial Pancreatic Cancer?

BACKGROUND

Individuals with a family history of pancreatic adenocarcinoma (PC) or with a germline mutation in a PC susceptibility gene are at increased risk of developing PC. These high-risk individuals (HRIs) may benefit from PC surveillance.

METHODS

A PC surveillance program was developed to evaluate the detection of premalignant lesions and early-stage PCs using biannual imaging and to determine whether locally advanced or metastatic PCs develop despite biannual surveillance. From January 2013 to April 2020, asymptomatic HRIs were enrolled and followed with alternating MRI and endoscopic ultrasound every 6 months.

RESULTS

Of 75 HRIs, 43 (57.3%) had a germline mutation in a PC susceptibility gene and 32 (42.7%) had a familial pancreatic cancer (FPC) pedigree. Branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) were identified in 26 individuals (34.7%), but only 2 developed progressive lesions. One patient with Peutz-Jeghers syndrome (PJS) developed locally advanced PC arising from a BD-IPMN. Whole-genome sequencing of this patient's PC and of a second patient with PJS-associated PC from the same kindred revealed biallelic inactivation of STK11 in a KRAS-independent manner. A review of 3,853 patients from 2 PC registries identified an additional patient with PJS-associated PC. All 3 patients with PJS developed advanced PC consistent with the malignant transformation of an underlying BD-IPMN in <6 months. The other surveillance patient with a progressive lesion had FPC and underwent resection of a mixed-type IPMN that harbored polyclonal KRAS mutations.

CONCLUSIONS

PC surveillance identifies a high prevalence of BD-IPMNs in HRIs. Patients with PJS with BD-IPMNs may be at risk for accelerated malignant transformation.

Long-term yield of pancreatic cancer surveillance in high-risk individuals

OBJECTIVE

We aimed to determine the long-term yield of pancreatic cancer surveillance in hereditary predisposed high-risk individuals.

DESIGN

From 2006 to 2019, we prospectively enrolled asymptomatic individuals with an estimated 10% or greater lifetime risk of pancreatic ductal adenocarcinoma (PDAC) after obligatory evaluation by a clinical geneticist and genetic testing, and subjected them to annual surveillance with both endoscopic ultrasonography (EUS) and MRI/cholangiopancreatography (MRI/MRCP) at each visit.

RESULTS

366 individuals (201 mutation-negative familial pancreatic cancer (FPC) kindreds and 165 PDAC susceptibility gene mutation carriers; mean age 54 years, SD 9.9) were followed for 63 months on average (SD 43.2). Ten individuals developed PDAC, of which four presented with a symptomatic interval carcinoma and six underwent resection. The cumulative PDAC incidence was 9.3% in the mutation carriers and 0% in the FPC kindreds (p<0.001). Median PDAC survival was 18 months (range 1-32). Surgery was performed in 17 individuals (4.6%), whose pathology revealed 6 PDACs (3 T1N0M0), 7 low-grade precursor lesions, 2 neuroendocrine tumours <2 cm, 1 autoimmune pancreatitis and in 1 individual no abnormality. There was no surgery-related mortality. EUS detected more solid lesions than MRI/MRCP (100% vs 22%, p<0.001), but less cystic lesions (42% vs 83%, p<0.001).

CONCLUSION

The diagnostic yield of PDAC was substantial in established high-risk mutation carriers, but non-existent in the mutation-negative proven FPC kindreds. Nevertheless, timely identification of resectable lesions proved challenging despite the concurrent use of two imaging modalities, with EUS outperforming MRI/MRCP. Overall, surveillance by imaging yields suboptimal results with a clear need for more sensitive diagnostic markers, including biomarkers.

Role of artificial intelligence in early detection and screening for pancreatic adenocarcinoma

Pancreatic adenocarcinoma remains to be one of the deadliest malignancies in the world despite treatment advancement over the past few decades. Its low survival rates and poor prognosis can be attributed to ambiguity in recommendations for screening and late symptom onset, contributing to its late presentation. In the recent years, artificial intelligence (AI) as emerged as a field to aid in the process of clinical decision making. Considerable efforts have been made in the realm of AI to screen for and predict future development of pancreatic ductal adenocarcinoma. This review discusses the use of AI in early detection and screening for pancreatic adenocarcinoma, and factors which may limit its use in a clinical setting.

Standardization of EUS imaging and reporting in high-risk individuals of pancreatic adenocarcinoma: consensus statement of the Pancreatic Cancer Early Detection Consortium

BACKGROUND AND AIMS

Pancreatic ductal adenocarcinoma is an aggressive disease most often diagnosed after local progression or metastatic dissemination, precluding resection and resulting in a high mortality rate. For individuals with elevated personal risk of the development of pancreatic cancer, EUS is a frequently used advanced imaging and diagnostic modality. However, variability in the expertise and definition of EUS findings exists among gastroenterologists, as well as a lack of standardized reporting of relevant findings at the time of examination. Adoption of standardized EUS reporting, using a universally accepted and agreed on terminology, is needed.

METHODS

A consensus statement designed to create a standardized reporting template was authored by a multidisciplinary group of experts in pancreatic diseases that includes gastroenterologists, radiologists, surgeons, oncologists, and geneticists. This statement was developed using a modified Delphi process as part of the Pancreatic Cancer Early Detection Consortium, and >75% agreement was required to reach consensus.

RESULTS

We identified reporting elements and present standardized reporting templates for EUS indications, procedural data, EUS image capture, and descriptors of findings, tissue sampling, and postprocedural assessment of adequacy.

CONCLUSIONS

Adoption of this standardized EUS reporting template should improve consistency in clinical decision-making for individuals with elevated risk of pancreatic cancer by providing complete and accurate reporting of pancreatic abnormalities. Standardization will also help to facilitate research and clinical trial design by using clearly defined and consistent imaging descriptions, thus allowing for comparison of results across different centers.

Late-Stage Pancreatic Cancer Detected During High-Risk Individual Surveillance: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Identification and resection of successful targets, that is, T₁ N₀M₀ pancreatic ductal adenocarcinoma (PDAC) and high-grade precursors during surveillance of high-risk individuals (HRIs) confers improved survival. Late-stage PDACs refer to T_2-4 N₀M₀ and nodal or distant metastatic PDAC stages diagnosed during the follow-up phase of HRI surveillance. This study aimed to quantify late-stage PDACs during HRI surveillance and identify associated clinicoradiologic factors.

METHODS

A systematic search (PROSPERO:CRD42018117189) from Cochrane Library, Embase, Google Scholar, Medline, PubMed, Scopus, and Web of Science was last performed on April 18, 2021. Only original HRI surveillance manuscripts that specified follow-up strategies were included, and studies with only baseline information were excluded. Cumulative incidences of advanced neoplasia: high-grade precursors and all PDACs, and surveillance-detected/interval late-stage PDACs were calculated through random-effects model. Incidence of late-stage PDACs underwent metaregression to identify association with HRI clinicoradiologic features. Publication bias was assessed through the funnel plot and Egger's regression line.

RESULTS

Thirteen original surveillance studies included 2169 HRIs followed over 7302.72 patient-years. Cumulative incidence of advanced neoplasia and late-stage PDACs was 3.3 (95% confidence interval [CI]: 0.6-7.4) and 1.7 (95% CI: 0.2-4.0) per 1000 patient-years, respectively. Late-stage PDACs lacked significant association with surveillance imaging, baseline pancreatic morphology, study location, genetic background, gender, or age. Limited information on diagnostic error, symptoms, timing of presentation, lesion site, and surveillance adherence precluded formal meta-analysis.

CONCLUSION

A sizeable proportion of late-stage PDACs were detected during follow-up. Their incidence lacked association with baseline clinicoradiologic features. Further causal investigation of stage-based outcomes is warranted for overall improvement in HRI surveillance.

Alterations in the Duodenal Fluid Microbiome of Patients With Pancreatic Cancer

BACKGROUND & AIMS

The tumor microbiome of patients with pancreas ductal adenocarcinoma (PDAC) includes bacteria normally present in the upper gastrointestinal tract. If the predominant source of intratumoral bacteria in patients with PDAC is retrograde migration from the duodenum, duodenal fluid could be a representative biospecimen for determining microbiome profiles of patients with PDAC or at risk of developing PDAC.

METHODS

We performed a case-control study comparing bacterial and fungal (16S and 18S rRNA) profiles of secretin-stimulated duodenal fluid collections from 308 patients undergoing duodenal endoscopy including 134 normal pancreas control subjects, 98 patients with pancreatic cyst(s) and 74 patients with PDAC.

RESULTS

Alterations in duodenal fluid microbiomes with diminished alpha diversity were significantly associated with age >70 and proton pump inhibitor use. Patients with PDAC had significantly decreased duodenal microbial alpha diversity compared with age-matched control subjects with normal pancreata and those with pancreatic cyst(s). There was evidence of enrichment of Bifidobacterium genera in the duodenal fluid of patients with PDAC compared with control subjects and those with pancreatic cyst(s). There were also enrichment of duodenal fluid Fusobacteria and Rothia bacteria among patients with PDAC with short-term survival. Duodenal fluid microbiome profiles were not significantly different between control subjects and patients with pancreatic cyst(s).

CONCLUSION

Patients with PDAC have alterations in their duodenal fluid microbiome profiles compared with patients with pancreatic cysts and those with normal pancreata. ClinicalTrials.gov, Number: NCT02000089.

ATM: Functions of ATM Kinase and Its Relevance to Hereditary Tumors

Ataxia-telangiectasia mutated (ATM) functions as a key initiator and coordinator of DNA damage and cellular stress responses. ATM signaling pathways contain many downstream targets that regulate multiple important cellular processes, including DNA damage repair, apoptosis, cell cycle arrest, oxidative sensing, and proliferation. Over the past few decades, associations between germline ATM pathogenic variants and cancer risk have been reported, particularly for breast and pancreatic cancers. In addition, given that ATM plays a critical role in repairing double-strand breaks, inhibiting other DNA repair pathways could be a synthetic lethal approach. Based on this rationale, several DNA damage response inhibitors are currently being tested in ATM-deficient cancers. In this review, we discuss the current knowledge related to the structure of the ATM gene, function of ATM kinase, clinical significance of ATM germline pathogenic variants in patients with hereditary cancers, and ongoing efforts to target ATM for the benefit of cancer patients.

Pancreatic Cancer Surveillance and Novel Strategies for Screening

Individuals with a genetic susceptibility to pancreatic ductal adenocarcinoma (PDAC) may benefit from surveillance to increase the likelihood of early detection. Currently, candidates for surveillance are identified based on genetic test results and family history of PDAC, and surveillance is accomplished through imaging of the pancreas (endoscopic ultrasound or MRI). Novel methods that incorporate personalized risk, biomarkers, and radiomics are being investigated in an attempt to improve identification of at-risk individuals and to increase detection of precursor and early-stage lesions.

Comparisons of Outcomes Between Adolescent and Young Adult with Older Patients After Radical Resection of Pancreatic Ductal Adenocarcinoma by Propensity Score Matching: A Single-Center Study

Purpose

Adolescent and young adult (AYA) pancreatic ductal adenocarcinoma (PDAC) occurs in patients below 40 years old. Whether AYA patients have worse outcomes compared with older patients is still controversial. The purpose of this study is to compare the outcomes of AYA patients and older patients after radical surgery for PDAC.

Methods

A single-center, retrospective, cohort study was conducted in patients who underwent radical surgery for PDAC in Xiangya Hospital Central South University from January 2007 to December 2019. The clinicopathological data and results of patients with PDAC were collected and analyzed retrospectively. They were divided into AYA group and older group based on age (<40, AYA group; ≥40, older group). Based on all the considered covariates except age, we estimated 1:2 case propensity score matching (PSM).

Results

A total of 1033 cases were enrolled, 46 cases (4.45%) in the AYA group. Both before and after PSM, the AYA patients have a higher preoperative CA19-9 than the older patients (P < 0.001) and (P < 0.001). Pathological results showed that AYA group had a higher microvascular invasion rate (P < 0.001 and P = 0.045) than older group. The median time of overall survival (OS) in AYA group and older group were 13 months (95% CI = 11.50-14.50) and 14 months (95% CI = 13.50-14.50), respectively. Additionally, AYA group have a worse 2-year OS rate than older group (8.70% vs 25.23%, P = 0.011 and 8.70% vs 25.00%, P = 0.023). According to the Log rank test, AYA group have a worse cumulative OS rate than older group (P = 0.002) and (P = 0.030), respectively.

Conclusion

PDAC might be more aggressive in AYA, and the cumulative OS after radical PDAC surgery in AYA patients is worse than that in older patients.

Endoplasmic stress-inducing variants in CPB1 and CPA1 and risk of pancreatic cancer: A case-control study and meta-analysis

Gene variants that encode pancreatic enzymes with impaired secretion can induce pancreatic acinar endoplasmic reticulum (ER) stress, cellular injury and pancreatitis. The role of such variants in pancreatic cancer risk has received little attention. We compared the prevalence of ER stress-inducing variants in CPA1 and CPB1 in patients with pancreatic ductal adenocarcinoma (PDAC cases), enrolled in the National Familial Pancreas Tumor Registry, to their prevalence in noncancer controls in the Genome Aggregation Database (gnomAD). Variants of unknown significance were expressed and variants with reduced secretion assessed for ER stress induction. In vitro assessments were compared with software predictions of variant function. Protein variant software was used to assess variants found in only one gnomAD control ("n-of-one" variants). A meta-analysis of prior PDAC case/control studies was also performed. Of the 1385 patients with PDAC, 0.65% were found to harbor an ER stress-inducing variant in CPA1 or CPB1, compared to 0.17% of the 64 026 controls (odds ratio [OR]: 3.80 [1.92-7.51], P = .0001). ER stress-inducing variants in the CPA1 gene were identified in 4 of 1385 PDAC cases vs 77 of 64 026 gnomAD controls (OR: 2.4 [0.88-6.58], P = .087), and variants in CPB1 were detected in 5 of 1385 cases vs 33 of 64 026 controls (OR: 7.02 [2.74-18.01], P = .0001). Meta-analysis demonstrated strong associations for pancreatic cancer and ER-stress inducing variants for both CPA1 (OR: 3.65 [1.58-8.39], P < .023) and CPB1 (OR: 9.51 [3.46-26.15], P < .001). Rare variants in CPB1 and CPA1 that induce ER stress are associated with increased odds of developing pancreatic cancer.

AGR2-Dependent Nuclear Import of RNA Polymerase II Constitutes a Specific Target of Pancreatic Ductal Adenocarcinoma in the Context of Wild-Type p53

BACKGROUND & AIMS

Promoted by pancreatitis, oncogenic KrasG12D triggers acinar cells' neoplastic transformation through acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia. Anterior gradient 2 (Agr2), a known inhibitor of p53, is detected at early stage of pancreatic ductal adenocarcinoma (PDAC) development. RNA polymerase II (RNAPII) is a key nuclear enzyme; regulation of its nuclear localization in mammalian cells represents a potential therapeutic target.

METHODS

A mouse model of inflammation-accelerated KrasG12D-driven ADM and pancreatic intraepithelial neoplasia development was used. Pancreas-specific Agr2 ablation was performed to access its role in pancreatic carcinogenesis. Hydrophobic hexapeptides loaded in liposomes were developed to disrupt Agr2-RNAPII complex.

RESULTS

We found that Agr2 is up-regulated in ADM-to-pancreatic intraepithelial neoplasia transition in inflammation and KrasG12D-driven early pancreatic carcinogenesis. Genetic ablation of Agr2 specifically blocks this metaplastic-to-neoplastic process. Mechanistically, Agr2 directs the nuclear import of RNAPII via its C-terminal nuclear localization signal, undermining the ATR-dependent p53 activation in ADM lesions. Because Agr2 binds to the largest subunit of RNAPII in a peptide motif-dependent manner, we developed a hexapeptide to interfere with the nuclear import of RNAPII by competitively disrupting the Agr2-RNAPII complex. This novel hexapeptide leads to dysfunction of RNAPII with concomitant activation of DNA damage response in early neoplastic lesions; hence, it dramatically compromises PDAC initiation in vivo. Moreover, the hexapeptide sensitizes PDAC cells and patient-derived organoids harboring wild-type p53 to RNAPII inhibitors and first-line chemotherapeutic agents in vivo. Of note, this therapeutic effect is efficient across various cancer types.

CONCLUSIONS

Agr2 is identified as a novel adaptor protein for nuclear import of RNAPII in mammalian cells. Also, we provide genetic evidence defining Agr2-dependent nuclear import of RNAPII as a pharmaceutically accessible target for prevention and treatment in PDAC in the context of wild-type p53.

Inherited Pancreatic Cancer Syndromes and High-Risk Screening

Pancreatic cancer is the third leading cause of cancer death in the United States, with a 5-year survival rate of 9%. Individuals with inherited pancreatic cancer syndromes are at an increased risk for developing pancreatic cancer and may benefit from pancreatic cancer surveillance with the goal to detect and intervene on early-stage cancer or high-risk precursor lesions. Given the screening implications for family members and therapeutic implications for probands, all patients diagnosed with pancreatic cancer are recommended to undergo germline genetic testing.

Hereditary pancreatic cancer

Pancreatic cancer is associated with both family and hereditary cancer syndromes. Multigene panel testing for pancreatic cancer detected the germline variants BRCA1/2, PALB2, ATM, TP53, MLH1, STK11/LKB1, APC, CDKN2A, and SPINK1/PRSS1 as high-risk genes. A latest genome-wide association study revealed the common, but low-risk germline variants in pancreatic cancer patients. Active pancreatic surveillance using magnetic resonance imaging and endoscopic ultrasound is recommended for high-risk individuals who have a family history of pancreatic cancer or harbor these germline pathogenic variants to improve the detection rate and prognosis of pancreatic cancer. Since poly-ADP-ribose polymerase (PARP) inhibitor has been shown to be effective in improving the prognosis of BRCA-positive pancreatic cancer as well as hereditary breast and ovarian cancer syndrome, PARP inhibitor therapy is currently being applied as precision medicine to pancreatic cancer patients harboring the BRCA1/2 germline variant. This review highlights the importance of surveillance for germline pathogenic variants in pancreatic cancer and is expected to lead to improvements in the diagnosis and prevention of pancreatic cancer as well as facilitate the development of effective therapeutic strategies and precision medicine.

Early detection of pancreatic cancer: current state and future opportunities

PURPOSE OF REVIEW

Pancreatic ductal adenocarcinoma (PDAC) is third leading cause of cancer death in the United States, a lethal disease with no screening strategy. Although diagnosis at an early stage is associated with improved survival, clinical detection of PDAC is typically at an advanced symptomatic stage when best in class therapies have limited impact on survival.

RECENT FINDINGS

In recent years this status quo has been challenged by the identification of novel risk factors, molecular markers of early-stage disease and innovations in pancreatic imaging. There is now expert consensus that screening may be pursued in a cohort of individuals with increased likelihood of developing PDAC based on genetic and familial risk.

SUMMARY

The current review summarizes the known risk factors of PDAC, current knowledge and recent observations pertinent to early detection of PDAC in these risk groups and outlines future approaches that will potentially advance the field.

The Role of Inherited Pathogenic CDKN2A Variants in Susceptibility to Pancreatic Cancer

ABSTRACT

CDKN2A is cell cycle negative regulator, and the role of CDKN2A in the development of pancreatic ductal adenocarcinoma, which continues to be a lethal cancer, is well-established. Somatic loss of CDKN2A is considered one of the major drivers of pancreatic tumorigenesis. CDKN2A gene is one of the pancreatic cancer susceptibility gene; in addition to melanoma, pathogenic germline CDKN2A variants have been identified in up to 3.3% patients with pancreatic ductal adenocarcinoma depending on family history of disease. Carriers of a known pathogenic germline CDKN2A variant have up to a 12.3-fold increased risk of developing pancreatic cancer. Recently, several studies have demonstrated the benefit of clinical surveillance in patients with pathogenic germline CDKN2A variants. Therefore, identification of patients with a pathogenic germline CDKN2A variant is important for screening of at-risk relatives for pancreatic cancer. It has the potential to lead to the detection of early, potentially curable pancreatic cancer and precursor neoplasms, and reduce mortality. Furthermore, patients with a germline pathogenic CDKN2A variant and somatic loss of CDKN2A may benefit in the future from treatment with targeted therapies, such as a CDK4/6 inhibitor.

Significant detection of new germline pathogenic variants in Australian Pancreatic Cancer Screening Program participants

BACKGROUND

The Australian Pancreatic Cancer Screening Program (APCSP) offers endoscopic ultrasound surveillance for individuals at increased risk of pancreatic ductal adenocarcinoma (PDAC) with all participants requiring assessment by a Familial Cancer Service before or after study enrolment.

METHODS

Individuals aged 40-80 years (or 10 years younger than the earliest PDAC diagnosis) were eligible for APCSP study entry if they had 1) ≥ two blood relatives with PDAC (at least one of first-degree association); 2) a clinical or genetic diagnosis of Hereditary Pancreatitis or Peutz-Jeghers syndrome irrespective of PDAC family history; or 3) a known PDAC predisposition germline pathogenic variant (BRCA2, PALB2, CDKN2A, or Lynch syndrome) with ≥one PDAC-affected first- or second-degree relative. Retrospective medical record review was conducted for APCSP participants enrolled at the participating Australian hospitals from January 2011 to December 2019. We audited the genetic investigations offered by multiple Familial Cancer Services who assessed APCSP participants according to national guidelines, local clinical protocol and/or the availability of external research-funded testing, and the subsequent findings. Descriptive statistical analysis was performed using Microsoft Excel.

RESULTS

Of 189 kindreds (285 participants), 50 kindreds (71 participants) had a known germline pathogenic variant at enrolment (BRCA2 n = 35, PALB2 n = 6, CDKN2A n = 3, STK11 n = 3, PRSS1 n = 2, MLH1 n = 1). Forty-eight of 136 (35%) kindreds with no known germline pathogenic variant were offered mutation analysis; 89% was clinic-funded, with increasing self-funded testing since 2016. The relatively low rates of genetic testing performed reflects initial strict criteria for clinic-funded genetic testing. New germline pathogenic variants were detected in five kindreds (10.4%) after study enrolment (BRCA2 n = 3 kindreds, PALB2 n = 1, CDKN2A n = 1). Of note, only eight kindreds were reassessed by a Familial Cancer Service since enrolment, with a further 21 kindreds identified as being suitable for reassessment.

CONCLUSION

Germline pathogenic variants associated with PDAC were seen in 29.1% of our high-risk cohort (55/189 kindreds; 82/285 participants). Importantly, 10.4% of kindreds offered genetic testing were newly identified as having germline pathogenic variants, with majority being BRCA2. As genetic testing standards evolve rapidly in PDAC, 5-yearly reassessment of high-risk individuals by Familial Cancer Services is warranted.

Germline sequence analysis of RABL3 in a large series of pancreatic ductal adenocarcinoma patients reveals no evidence of deleterious variants

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with a 5-year survival rate of less than 10%. Individuals with a pathogenic germline variant in a pancreatic cancer susceptibility gene are at an increased risk of developing pancreatic cancer. Understanding the inherited genetic basis of pancreatic tumor development provides a unique opportunity to improve patient care and outcomes. For example, relatives of a patients with PDAC who have a pathogenic germline variant in a pancreatic cancer susceptibility gene are eligible for disease surveillance where cancers may be detected early, and 5-year survival greatly improved. Furthermore, for some patients with PDAC and a pathogenic germline variant in a pancreatic cancer susceptibility gene, their tumors may be susceptible to specific anti-cancer therapies. Recently, RABL3 was identified as a pancreatic cancer susceptibility gene. To validate these findings and inform clinical translation, we determined the prevalence of deleterious RABL3 variants in a large cohort of 1037 patients with PDAC that had undergone either whole genome or whole exome germline sequencing. We identified two synonymous variants and four missense variants classified as variants of unknown significance. We found no pathogenic RABL3 variants, indicating that the maximum prevalence of such variants in patients with PDAC is less than 0.36% (minor allele frequency 0, 97.5% one-sided confidence interval: 0-0.0036). This finding has important implications for germline genetic testing of patients with PDAC.

The molecular biology of pancreatic adenocarcinoma: translational challenges and clinical perspectives

Pancreatic cancer is an increasingly common cause of cancer mortality with a tight correspondence between disease mortality and incidence. Furthermore, it is usually diagnosed at an advanced stage with a very dismal prognosis. Due to the high heterogeneity, metabolic reprogramming, and dense stromal environment associated with pancreatic cancer, patients benefit little from current conventional therapy. Recent insight into the biology and genetics of pancreatic cancer has supported its molecular classification, thus expanding clinical therapeutic options. In this review, we summarize how the biological features of pancreatic cancer and its metabolic reprogramming as well as the tumor microenvironment regulate its development and progression. We further discuss potential biomarkers for pancreatic cancer diagnosis, prediction, and surveillance based on novel liquid biopsies. We also outline recent advances in defining pancreatic cancer subtypes and subtype-specific therapeutic responses and current preclinical therapeutic models. Finally, we discuss prospects and challenges in the clinical development of pancreatic cancer therapeutics.

Combinations of Low-Frequency Genetic Variants Might Predispose to Familial Pancreatic Cancer

Familial pancreatic cancer (FPC) is an established but rare inherited tumor syndrome that accounts for approximately 5% of pancreatic ductal adenocarcinoma (PDAC) cases. No major causative gene defect has yet been identified, but germline mutations in predisposition genes BRCA1/2, CDKN2A and PALB2 could be detected in 10–15% of analyzed families. Thus, the genetic basis of disease susceptibility in the majority of FPC families remains unknown. In an attempt to identify new candidate genes, we performed whole-genome sequencing on affected patients from 15 FPC families, without detecting BRCA1/2, CDKN2A or PALB2 mutations, using an Illumina based platform. Annotations from CADD, PolyPhen-2, SIFT, Mutation Taster and PROVEAN were used to assess the potential impact of a variant on the function of a gene. Variants that did not segregate with pancreatic disease in respective families were excluded. Potential predisposing candidate genes ATM, SUFU, DAB1, POLQ, FGFBP3, MAP3K3 and ACAD9 were identified in 7 of 15 families. All identified gene mutations segregated with pancreatic disease, but sometimes with incomplete penetrance. An analysis of up to 46 additional FPC families revealed that the identified gene mutations appeared to be unique in most cases, despite a potentially deleterious ACAD9 Ala326Thr germline variant, which occurred in 4 (8.7%) of 46 FPC families. Notably, affected PDAC patients within a family carried identical germline mutations in up to three different genes, e.g., DAB1, POLQ and FGFBP3. These results support the hypothesis that FPC is a highly heterogeneous polygenetic disease caused by low-frequency or rare variants.

Recent Trends in the Incidence and Survival of Stage 1A Pancreatic Cancer: A Surveillance, Epidemiology, and End Results Analysis

BACKGROUND

Rapid access to pancreatic imaging and regular pancreatic surveillance may help identify stage I pancreatic cancer. We investigated recent trends in the stage of newly diagnosed pancreatic ductal adenocarcinoma (PDACs), age at diagnosis, and survival.

METHODS

Trends in age-adjusted incidence of stage IA PDAC between 2004 and 2016 were determined from the National Cancer Institute's Surveillance, Epidemiology and End Results database. All tests were two-sided.

RESULTS

The incidence of stage IA PDAC cases diagnosed increased statistically significantly from 2004 to 2016 (annual percent change = 14.5, 95% confidence interval [CI] = 11.4 to 17.7; P < .001). During the study period, average age at diagnosis for stage IA and IB casesAQ3 declined by 3.5 years (95% CI = 1.2 to 5.9; P = .004) and 5.5 years (95% CI = 3.4 to 7.6; P < .001), whereas average age increased for higher-stage cases (by 0.6 to 1.4 years). Among stage IA cases, the proportion of blacks was smaller (10.2% vs 12.5%), and the proportion of other non-Caucasians was higher compared with higher-stage cases (11.9% vs 8.4%; P < .001). Stage IA cases were more likely to carry insurance (vs Medicaid or none) than higher-stage cases (cases aged younger than 65 years; odds ratio = 2.45, 95% CI = 1.96 to 3.06; P < .001). The 5-year overall survival for stage IA PDAC improved from 44.7% (95% CI = 31.4 to 63.7) in 2004 to 83.7% (95% CI = 78.6% to 89.2%) in 2012; 10-year survival improved from 36.7% (95% CI = 24.1 to 55.8) in 2004 to 49.0% (95% CI = 37.2% to 64.6%) in 2007.

CONCLUSIONS

In recent years, the proportion of patients diagnosed with stage IA PDAC has increased, their average age at diagnosis has decreased, and their overall survival has improved. These trends may be the result of improved early diagnosis and early detection.

Artificial Intelligence and Early Detection of Pancreatic Cancer: 2020 Summative Review

ABSTRACT

Despite considerable research efforts, pancreatic cancer is associated with a dire prognosis and a 5-year survival rate of only 10%. Early symptoms of the disease are mostly nonspecific. The premise of improved survival through early detection is that more individuals will benefit from potentially curative treatment. Artificial intelligence (AI) methodology has emerged as a successful tool for risk stratification and identification in general health care. In response to the maturity of AI, Kenner Family Research Fund conducted the 2020 AI and Early Detection of Pancreatic Cancer Virtual Summit (www.pdac-virtualsummit.org) in conjunction with the American Pancreatic Association, with a focus on the potential of AI to advance early detection efforts in this disease. This comprehensive presummit article was prepared based on information provided by each of the interdisciplinary participants on one of the 5 following topics: Progress, Problems, and Prospects for Early Detection; AI and Machine Learning; AI and Pancreatic Cancer-Current Efforts; Collaborative Opportunities; and Moving Forward-Reflections from Government, Industry, and Advocacy. The outcome from the robust Summit conversations, to be presented in a future white paper, indicate that significant progress must be the result of strategic collaboration among investigators and institutions from multidisciplinary backgrounds, supported by committed funders.

High Detection Rates of Pancreatic Cancer Across Stages by Plasma Assay of Novel Methylated DNA Markers and CA19-9

PURPOSE

We have previously identified tissue methylated DNA markers (MDMs) associated with pancreatic ductal adenocarcinoma (PDAC). In this case-control study, we aimed to assess the diagnostic performance of plasma MDMs for PDAC.

EXPERIMENTAL DESIGN

Thirteen MDMs (GRIN2D, CD1D, ZNF781, FER1L4, RYR2, CLEC11A, AK055957, LRRC4, GH05J042948, HOXA1, PRKCB, SHISA9, and NTRK3) were identified on the basis of selection criteria applied to results of prior tissue experiments and assays were optimized in plasma. Next, 340 plasma samples (170 PDAC cases and 170 controls) were assayed using target enrichment long-probe quantitative amplified signal method. Initially, 120 advanced-stage PDAC cases and 120 healthy controls were used to train a prediction algorithm at 97.5% specificity using random forest modeling. Subsequently, the locked algorithm derived from the training set was applied to an independent blinded test set of 50 early-stage PDAC cases and 50 controls. Finally, data from all 340 patients were combined, and cross-validated.

RESULTS

The cross-validated area under the receiver operating characteristic curve (AUC) for the training set was 0.93 (0.89-0.96) for the MDM panel alone, 0.91 (95% confidence interval, 0.87-0.96) for carbohydrate antigen 19-9 (CA19-9) alone, and 0.99 (0.98-1) for the combined MDM-CA19-9 panel. In the test set of early-stage PDAC, the AUC for MDMs alone was 0.84 (0.76-0.92), CA19-9 alone was 0.87 (0.79-0.94), and combined MDM-CA19-9 panel was 0.90 (0.84-0.97) significantly better compared with either MDMs alone or CA19-9 alone (P = 0.0382 and 0.0490, respectively). At a preset specificity of 97.5%, the sensitivity for the combined panel in the test set was 80% (28%-99%) for stage I disease and 82% (68%-92%) for stage II disease. Using the combined datasets, the cross-validated AUC was 0.9 (0.86-0.94) for the MDM panel alone and 0.89 for CA19-9 alone (0.84-0.93) versus 0.97 (0.94-0.99) for the combined MDM-CA19-9 panel (P ≤ 0.0001). Overall, cross-validated sensitivity of MDM-CA19-9 panel was 92% (83%-98%), with an observed specificity of 92% at the preset specificity of 97.5%.

CONCLUSIONS

Plasma MDMs in combination with CA19-9 detect PDAC with significantly higher accuracy compared with either biomarker individually.

The Management of Peutz-Jeghers Syndrome: European Hereditary Tumour Group (EHTG) Guideline

The scientific data to guide the management of Peutz–Jeghers syndrome (PJS) are sparse. The available evidence has been reviewed and discussed by diverse medical specialists in the field of PJS to update the previous guideline from 2010 and formulate a revised practical guideline for colleagues managing PJS patients. Methods: Literature searches were performed using MEDLINE, Embase, and Cochrane. Evidence levels and recommendation strengths were assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). A Delphi process was followed, with consensus being reached when ≥80% of the voting guideline committee members agreed. Recommendations and statements: The only recent guidelines available were for gastrointestinal and pancreatic management. These were reviewed and endorsed after confirming that no more recent relevant papers had been published. Literature searches were performed for additional questions and yielded a variable number of relevant papers depending on the subject addressed. Additional recommendations and statements were formulated. Conclusions: A decade on, the evidence base for recommendations remains poor, and collaborative studies are required to provide better data about this rare condition. Within these restrictions, multisystem, clinical management recommendations for PJS have been formulated.

Elevated hemoglobin A1c is associated with the presence of pancreatic cysts in a high-risk pancreatic surveillance program

Background

Emerging evidence demonstrates that surveillance of individuals at high-risk (HRIs) of developing pancreatic adenocarcinoma allows for identification and treatment of resectable tumors with improved survival. Population-based data suggest that hyperglycemia may be present up to three years before the development of pancreatic cancer. We investigated whether elevated hemoglobin A1c (HbA1c) is associated with the development of pancreatic cysts in a pancreatic surveillance program.

Methods

We performed a retrospective study of HRIs who underwent pancreatic surveillance at a single institution between May 2013 and March 2019, according to published criteria. We collected demographic information, clinical data including HbA1c, and imaging results. We compared data using univariable and multivariable analyses. Our primary outcome was the presence of pancreatic cysts on initial surveillance in patients with elevated HbA1c.

Results

Ninety-eight patients underwent surveillance imaging via EUS or MRCP and seventy-four patients met inclusion criteria. Thirty patients were found to have cysts on initial imaging. Older age (p < 0.01) and HbA1c in the prediabetic range or higher (p = 0.01) were associated with the presence of cysts or solid lesions on univariable analysis. After controlling for confounders, age (aOR 9.08, 95% CI 2.29–36.10), and HbA1c > 5.7% (aOR 5.82, 95% CI 1.50–22.54) remained associated with presence of cysts and solid lesions in HRIs. In patients with cysts or solid lesions there was a strong association between increased age and elevated HbA1c (p < 0.01).

Conclusion

HRIs with elevated HbA1c were more likely to have pancreatic cysts compared to individuals with lower HbA1c on initial imaging in a pancreatic surveillance program. These findings may help tailor the surveillance protocols for those at increased risk of developing pancreatic adenocarcinoma.

The genetics of ductal adenocarcinoma of the pancreas in the year 2020: dramatic progress, but far to go

The publication of the "Pan-Cancer Atlas" by the Pan-Cancer Analysis of Whole Genomes Consortium, a partnership formed by The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC), provides a wonderful opportunity to reflect on where we stand in our understanding of the genetics of pancreatic cancer, as well as on the opportunities to translate this understanding to patient care. From germline variants that predispose to the development of pancreatic cancer, to somatic mutations that are therapeutically targetable, genetics is now providing hope, where there once was no hope, for those diagnosed with pancreatic cancer.