Familial Pancreatic Cancer: Current Perspectives

Identification of RAD17 as a candidate cancer predisposition gene in families with histories of pancreatic and breast cancers

BACKGROUND

Among the 10% of pancreatic cancers that occur in a familial context, around a third carry a pathogenic variant in a cancer predisposition gene. Genetic studies of pancreatic cancer predisposition are limited by high mortality rates amongst index patients and other affected family members. The genetic risk for pancreatic cancer is often shared with breast cancer susceptibility genes, most notably BRCA2, PALB2, ATM and BRCA1. Therefore, we hypothesized that additional shared genetic etiologies might be uncovered by studying families presenting with both breast and pancreatic cancer.

METHODS

Focusing on a multigene panel of 276 DNA Damage Repair (DDR) genes, we performed next-generation sequencing in a cohort of 41 families with at least three breast cancer cases and one pancreatic cancer. When the index patient with pancreatic cancer was deceased, close relatives (first or second-degree) affected with breast cancer were tested (39 families).

RESULTS

We identified 27 variants of uncertain significance in DDR genes. A splice site variant (c.1605 + 2T > A) in the RAD17 gene stood out, as a likely loss of function variant. RAD17 is a checkpoint protein that recruits the MRN (MRE11-RAD50-NBS1) complex to initiate DNA signaling, leading to DNA double-strand break repair.

CONCLUSION

Within families with breast and pancreatic cancer, we identified RAD17 as a novel candidate predisposition gene. Further genetic studies are warranted to better understand the potential pathogenic effect of RAD17 variants and in other DDR genes.

Use of multi-gene panels in patients at high risk of hereditary digestive cancer: position statement of AEG, SEOM, AEGH and IMPaCT-GENÓMICA consortium

This position statement, sponsored by the Asociación Española de Gastroenterología, the Sociedad Española de Oncología Médica, the Asociación Española de Genética Humana and the IMPaCT-Genómica Consortium aims to establish recommendations for use of multi-gene panel testing in patients at high risk of hereditary gastrointestinal and pancreatic cancer. To rate the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We reached a consensus among experts using a Delphi method. The document includes recommendations on clinical scenarios where multi-gene panel testing is recommended in colorectal cancer, polyposis syndromes, gastric and pancreatic cancer, as well as the genes to be considered in each clinical scenario. Recommendations on the evaluation of mosaicisms, counseling strategies in the absence of an index subject and, finally, constitutional analysis after identification of pathogenic tumor variants are also made.

Joint Linkage and Association Analysis Using GENEHUNTER-MODSCORE with an Application to Familial Pancreatic Cancer

INTRODUCTION

Joint linkage and association (JLA) analysis combines two disease gene mapping strategies: linkage information contained in families and association information contained in populations. Such a JLA analysis can increase mapping power, especially when the evidence for both linkage and association is low to moderate. Similarly, an association analysis based on haplotypes instead of single markers can increase mapping power when the association pattern is complex.

METHODS

In this paper, we present an extension to the GENEHUNTER-MODSCORE software package that enables a JLA analysis based on haplotypes and uses information from arbitrary pedigree types and unrelated individuals. Our new JLA method is an extension of the MOD score approach for linkage analysis, which allows the estimation of trait-model and linkage disequilibrium (LD) parameters, i.e., penetrance, disease-allele frequency, and haplotype frequencies. LD is modeled between alleles at a single diallelic disease locus and up to three diallelic test markers. Linkage information is contributed by additional multi-allelic flanking markers. We investigated the statistical properties of our JLA implementation using extensive simulations, and we compared our approach to another commonly used single-marker JLA test. To demonstrate the applicability of our new method in practice, we analyzed pedigree data from the German National Case Collection for Familial Pancreatic Cancer (FaPaCa).

RESULTS

Based on the simulated data, we demonstrated the validity of our JLA-MOD score analysis implementation and identified scenarios in which haplotype-based tests outperformed the single-marker test. The estimated trait-model and LD parameters were in good accordance with the simulated values. Our method outperformed another commonly used JLA single-marker test when the LD pattern was complex. The exploratory analysis of the FaPaCa families led to the identification of a promising genetic region on chromosome 22q13.33, which can serve as a starting point for future mutation analysis and molecular research in pancreatic cancer.

CONCLUSION

Our newly proposed JLA-MOD score method proves to be a valuable gene mapping and characterization tool, especially when either linkage or association information alone provide insufficient power to identify the disease-causing genetic variants.

Pancreatic Cancer and the Family Connection: The Role of Advanced Practitioners in Screening and Educating Genetically At-Risk Individuals

Pancreatic cancer is the third leading cause of cancer deaths in the United States. It has a 95% mortality rate within 5 years of the initial diagnosis. Pancreatic ductal adenocarcinoma is the most commonly diagnosed histotype. The average age at diagnosis is 70 years. Familial forms of pancreatic cancer have been associated with pathogenic variants in predisposing genes, including ATM, BRCA1, BRCA2, PALB2, CDKN2A, STK11, MLH1, and MSH2. Collecting information on the patient's family history may serve as a primary tool to screen an individual's risk for familial pancreatic cancer. More advanced screening options for individuals at risk include endoscopic ultrasonography, magnetic resonance imaging, and magnetic resonance cholangiopancreatography. Due to pancreatic cancer's high mortality rate, routine screening of individuals at risk for developing familial pancreatic cancer may result in early diagnosis and improved survivability. This review aims to characterize the genetic risk factors associated with pancreatic cancer and recognize available screening options for at-risk individuals.

Racial and Gender Disparities Among Obese Patients With Pancreatic Cancer: A Trend Analysis in the United States

BACKGROUND

Pancreatic cancer (PC) is the third leading cause of cancer death. Obesity can increase the risk of PC by up to 50%. Studies have shown racial and gender disparities in PC, however, there is a paucity of such information in obese PC patients.

AIM

The aim of this study was to: (1) evaluate the incidence and prevalence of obesity among PC patients in the United States over the last 15 years, and (2) determine if variation exists in the demographic of obese PC patients over the last 15 years. It is hoped that this information could be used to assist in primary prevention and early detection of PC.

METHODS

A population-based retrospective analysis in IBM Explorys, a pooled, national, deidentified database of 63 million patients from 300 hospitals in the United States. Patient populations were identified using SNOMED and ICD codes. Cochrane-Armitage testing was performed to analyze trends in obesity among PC. Subgroup analysis for gender, age, race, and mortality rate were assessed.

RESULTS

The percentage of obese patients with PC increased over the 15-year period (2.5% to 8.5%, P <0.0001). Rates of obesity among PC patients increased among females ( P =0.0004), individuals under age 65 years ( P =0.0002), and all races, but especially for African Americans ( P =0.0007) and those in minority groups.

CONCLUSION

Awareness of disparities in PC and applying targeted care to those at increased risk are essential to improve future outcomes, including increased health care access and recruitment in research studies for minority groups.

Circulating Cell-Free Nucleic Acids as Biomarkers for Diagnosis and Prognosis of Pancreatic Cancer

A lack of reliable early diagnostic tools represents a major challenge in the management of pancreatic cancer (PCa), as the disease is often only identified after it reaches an advanced stage. This highlights the urgent need to identify biomarkers that can be used for the early detection, staging, treatment monitoring, and prognosis of PCa. A novel approach called liquid biopsy has emerged in recent years, which is a less- or non-invasive procedure since it focuses on plasmatic biomarkers such as DNA and RNA. In the blood of patients with cancer, circulating tumor cells (CTCs) and cell-free nucleic acids (cfNAs) have been identified such as DNA, mRNA, and non-coding RNA (miRNA and lncRNA). The presence of these molecules encouraged researchers to investigate their potential as biomarkers. In this article, we focused on circulating cfNAs as plasmatic biomarkers of PCa and analyzed their advantages compared to traditional biopsy methods.

Pancreatic Cancer Surveillance in Carriers of a Germline Pathogenic Variant in CDKN2A

Three percent of patients with pancreatic ductal adenocarcinoma (PDAC) present a germline pathogenic variant (GPV) associated with an increased risk of this tumor, CDKN2A being one of the genes associated with the highest risk. There is no clear consensus on the recommendations for surveillance in CDKN2A GPV carriers, although the latest guidelines from the International Cancer of the Pancreas Screening Consortium recommend annual endoscopic ultrasound (EUS) or magnetic resonance imaging (MRI) regardless of family history. Our aim is to describe the findings of the PDAC surveillance program in a cohort of healthy CDKN2A GPV heterozygotes. This is an observational analysis of prospectively collected data from all CDKN2A carriers who underwent screening for PDAC at the high-risk digestive cancer clinic of the “Hospital Clínic de Barcelona” between 2013 and 2021. A total of 78 subjects were included. EUS or MRI was performed annually with a median follow-up of 66 months. Up to 17 pancreatic findings were described in 16 (20.5%) individuals under surveillance, although most of them were benign. No significant precursor lesions were identified, but an early PDAC was detected and treated. While better preventive strategies are developed, we believe that annual surveillance with EUS and/or MRI in CDKN2A GPV heterozygotes may be beneficial.

Familial pancreatic cancer

Pancreatic cancer (PC) carries a poor prognosis with an overall 5-year survival of less than 10%. Early diagnosis, though cumbersome, is essential to allow complete surgical resection. Therefore, primary and secondary prevention are critical to reduce the incidence and to potentially prevent mortality. Given a relatively low lifetime risk of developing PC, identification of high-risk individuals is crucial to allow identification of pre-malignant lesions and small, localized tumors. Although 85-90% of PC cases are sporadic, we could consider risk stratification for the 5-10% of patients with a family history and the 3-5% of cases due to inherited genetic syndromes. These high-risk populations should be considered for screening and surveillance of PC. MRI/MRCP and EUS are the preferred modalities, due to their high sensitivity in lesion detection. Surveillance should be personalized, considering genetics and family history, and assessment of risk factors that may increase cancer risk. Screening programs should be limited to tertiary referral center, with high-volumes and adequate facilities to manage these patients.

Hereditary cancer syndromes

Hereditary cancer syndromes (HCSs) are arguably the most frequent category of Mendelian genetic diseases, as at least 2% of presumably healthy subjects carry highly-penetrant tumor-predisposing pathogenic variants (PVs). Hereditary breast-ovarian cancer and Lynch syndrome make the highest contribution to cancer morbidity; in addition, there are several dozen less frequent types of familial tumors. The development of the majority albeit not all hereditary malignancies involves two-hit mechanism, i.e. the somatic inactivation of the remaining copy of the affected gene. Earlier studies on cancer families suggested nearly fatal penetrance for the majority of HCS genes; however, population-based investigations and especially large-scale next-generation sequencing data sets demonstrate that the presence of some highly-penetrant PVs is often compatible with healthy status. Hereditary cancer research initially focused mainly on cancer detection and prevention. Recent studies identified multiple HCS-specific drug vulnerabilities, which translated into the development of highly efficient therapeutic options.

Proteomics biomarker discovery for individualized prevention of familial pancreatic cancer using statistical learning

BACKGROUND

The low five-year survival rate of pancreatic ductal adenocarcinoma (PDAC) and the low diagnostic rate of early-stage PDAC via imaging highlight the need to discover novel biomarkers and improve the current screening procedures for early diagnosis. Familial pancreatic cancer (FPC) describes the cases of PDAC that are present in two or more individuals within a circle of first-degree relatives. Using innovative high-throughput proteomics, we were able to quantify the protein profiles of individuals at risk from FPC families in different potential pre-cancer stages. However, the high-dimensional proteomics data structure challenges the use of traditional statistical analysis tools. Hence, we applied advanced statistical learning methods to enhance the analysis and improve the results' interpretability.

METHODS

We applied model-based gradient boosting and adaptive lasso to deal with the small, unbalanced study design via simultaneous variable selection and model fitting. In addition, we used stability selection to identify a stable subset of selected biomarkers and, as a result, obtain even more interpretable results. In each step, we compared the performance of the different analytical pipelines and validated our approaches via simulation scenarios.

RESULTS

In the simulation study, model-based gradient boosting showed a more accurate prediction performance in the small, unbalanced, and high-dimensional datasets than adaptive lasso and could identify more relevant variables. Furthermore, using model-based gradient boosting, we discovered a subset of promising serum biomarkers that may potentially improve the current screening procedure of FPC.

CONCLUSION

Advanced statistical learning methods helped us overcome the shortcomings of an unbalanced study design in a valuable clinical dataset. The discovered serum biomarkers provide us with a clear direction for further investigations and more precise clinical hypotheses regarding the development of FPC and optimal strategies for its early detection.

Pesticides and pancreatic adenocarcinoma: A transversal epidemiological, environmental and mechanistic narrative review

Pancreatic adenocarcinoma (PA) incidence is rising worldwide, especially in France. The evolution of known risk factors such as tobacco smoking, obesity, type 2 diabetes, chronic pancreatitis, or constitutional mutations is not sufficient to explain this trend. Pesticides are known risk factors in other malignancies. Previous studies have outlined pesticides' influence in PA, such as dichlorodiphenyltrichloroethane as plausible risk factors. The general population is directly or indirectly exposed to pesticides through air, food or water. Some of these chemicals may accumulate in the body all along lifetime and may harm carriers. The toxic mixing effects of these chemicals are not well documented. Several hypotheses have been put forward to explain how pesticides can induce indirect (fatty pancreas, induced diabetes) or direct (oxidative stress, cell damage) carcinogenesis in pancreatic cells through inflammation. A strong corpus exists acknowledging pesticides as a PA risk factor. However, published studies do not provide a sufficient level of evidence to prove causality and current prospective case-control studies are still ongoing.

Screening of pancreatic cancer: Target population, optimal timing and how?

Pancreatic cancer patients usually present at a late stage due to subtle clinical manifestations. One of the most predictive prognostic factors in pancreatic cancer is the pancreatic cancer stage at diagnosis; therefore, early diagnosis is essential. Until now, pancreatic cancer screening has not become a standard practice for the general population due to the low incidence. In current circumstances, targeting individuals with a high risk of pancreatic cancer may be more rational. Several screening modalities for pancreatic cancer have also become debatable topics. Therefore, this article will review current evidence and recommendations regarding pancreatic screening cancer protocol in general and in high-risk populations.

Surgical management of familial pancreatic cancer: a systematic review of the literature

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is the third most common cause of cancer-related mortality. The fact that the vast majority of patients with PDAC are diagnosed at an advanced stage highlights the need of early diagnosis. As hereditary factors are associated with approximately 5% of all PDAC cases, a screening programme to these high-risk individuals (HRI) has been proposed. The aim of screening methods is to identify selected group of patients with morphological abnormalities at an early stage, in order to be treated promptly. In this study, we evaluate the surgical outcomes and the appropriateness of pancreatic resection in HRIs who were selected for screening.

METHODS

A systematic literature search of the PubMed, Embase, and Cochrane databases was performed. The clinicopathological features were recorded and evaluated.

RESULTS

Six studies were selected for data collection. A total number of 77 patients were identified. Twenty-one patients had a germline mutation, with CDKN2A being the most prominent one (15.6%). Distal pancreatectomy was the most common surgical procedure (42.8%), followed by pancreaticoduodenectomy (33.8%). The mean disease-free survival was 23.6 months and tumour recurrence occurred in 9 patients (11.7%). Disease-specific mortality was 17.8%, while overall mortality was 19.5%. The most frequently reported postoperative diagnosis was PDAC (28 cases, 38.9%), followed by IPMN (23 cases, 31.9%), whereas high-grade PanIN lesions were found in 13 patients (18.1%).

CONCLUSION

High-risk individuals for pancreatic cancer, who are eventually operated may have a relatively uneventful postoperative course, however the oncological outcomes are comparable to the general population.

Current status of inherited pancreatic cancer

Background

It is estimated that about 10% of pancreatic cancer cases have a genetic background. People with a familial predisposition to pancreatic cancer can be divided into 2 groups. The first is termed hereditary pancreatic cancer, which occurs in individuals with a known hereditary cancer syndrome caused by germline single gene mutations (e.g., BRCA1/2, CDKN2A). The second is considered as familial pancreatic cancer, which is associated with several genetic factors responsible for the more common development of pancreatic cancer in certain families, but the precise single gene mutation has not been found.

Aim

This review summarizes the current state of knowledge regarding the risk of pancreatic cancer development in hereditary pancreatic cancer and familial pancreatic cancer patients. Furthermore, it gathers the latest recommendations from the three major organizations dealing with the prevention of pancreatic cancer in high-risk groups and explores recent guidelines of scientific societies on screening for pancreatic cancers in individuals at risk for hereditary or familial pancreatic cancer.

Conclusions

In order to improve patients’ outcomes, authors of current guidelines recommend early and intensive screening in patients with pancreatic cancer resulting from genetic background. The screening should be performed in excellence centers. The scope, extent and cost-effectiveness of such interventions requires further studies.

Resistance to Gemcitabine in Pancreatic Ductal Adenocarcinoma: A Physiopathologic and Pharmacologic Review

Pancreatic ductal adenocarcinoma (PDAC) is a very aggressive tumor with a poor prognosis and inadequate response to treatment. Many factors contribute to this therapeutic failure: lack of symptoms until the tumor reaches an advanced stage, leading to late diagnosis; early lymphatic and hematic spread; advanced age of patients; important development of a pro-tumoral and hyperfibrotic stroma; high genetic and metabolic heterogeneity; poor vascular supply; a highly acidic matrix; extreme hypoxia; and early development of resistance to the available therapeutic options. In most cases, the disease is silent for a long time, andwhen it does become symptomatic, it is too late for ablative surgery; this is one of the major reasons explaining the short survival associated with the disease. Even when surgery is possible, relapsesare frequent, andthe causes of this devastating picture are the low efficacy ofand early resistance to all known chemotherapeutic treatments. Thus, it is imperative to analyze the roots of this resistance in order to improve the benefits of therapy. PDAC chemoresistance is the final product of different, but to some extent, interconnected factors. Surgery, being the most adequate treatment for pancreatic cancer and the only one that in a few selected cases can achieve longer survival, is only possible in less than 20% of patients. Thus, the treatment burden relies on chemotherapy in mostcases. While the FOLFIRINOX scheme has a slightly longer overall survival, it also produces many more adverse eventsso that gemcitabine is still considered the first choice for treatment, especially in combination with other compounds/agents. This review discusses the multiple causes of gemcitabine resistance in PDAC.

Familial Predisposition and Genetic Risk Factors Associated with Pancreatic Cancer

Pancreatic cancer (PC) is a highly lethal cancer and projected to be the second leading cause of cancer death by 2030. Multigene panel testing has facilitated the identification of germline variants associated with an increased risk of PC. Precision treatment has led to improved outcomes for patients with these findings. Because of these improved outcomes as well as the implications for at-risk family members who may benefit from additional cancer screening, the NCCN recommends universal genetic testing for newly diagnosed PC patients. This review describes the most common heritable conditions associated with PC and those who may benefit from screening.

Prevalence of Germline Pathogenic Variants in Cancer Predisposing Genes in Czech and Belgian Pancreatic Cancer Patients

Simple Summary

We performed genetic analysis of 53 cancer predisposing genes in Belgian and Czech pancreatic cancer patients. In known pancreatic cancer predisposing genes, a high mutation detection ratio was observed in patients with multiple primary tumors and/or a family history of pancreatic or breast, ovarian or colon cancer or melanoma. BRCA1, BRCA2, and ATM were most frequently affected. Pathogenic variants in cancer predisposition genes for which the association with pancreatic cancer has not been firmly established, were less frequent, except for CHEK2. This observation warrants further analyses in other populations. To accurately determine risk associations our study highlights the importance of using a geographically-matched control population.

Abstract

(1) Background: The proportion and spectrum of germline pathogenic variants (PV) associated with an increased risk for pancreatic ductal adenocarcinoma (PDAC) varies among populations. (2) Methods: We analyzed 72 Belgian and 226 Czech PDAC patients by multigene panel testing. The prevalence of pathogenic variants (PV) in relation to personal/family cancer history were evaluated. PDAC risks were calculated using both gnomAD-NFE and population-matched controls. (3) Results: In 35/298 (11.7%) patients a PV in an established PDAC-predisposition gene was found. BRCA1/2 PV conferred a high risk in both populations, ATM and Lynch genes only in the Belgian subgroup. PV in other known PDAC-predisposition genes were rarer. Interestingly, a high frequency of CHEK2 PV was observed in both patient populations. PV in PDAC-predisposition genes were more frequent in patients with (i) multiple primary cancers (12/38; 32%), (ii) relatives with PDAC (15/56; 27%), (iii) relatives with breast/ovarian/colorectal cancer or melanoma (15/86; 17%) but more rare in sporadic PDAC (5/149; 3.4%). PV in homologous recombination genes were associated with improved overall survival (HR = 0.51; 95% CI 0.34–0.77). (4) Conclusions: Our analysis emphasizes the value of multigene panel testing in PDAC patients, especially in individuals with a positive family cancer history, and underlines the importance of population-matched controls for risk assessment.

Clinical features of patients with pancreatic ductal adenocarcinoma with a history of other primary malignancies: A retrospective analysis

Patients with pancreatic ductal adenocarcinoma (PDAC) that have a history of other primary malignancies are not well documented. The current study therefore aimed to evaluate the clinicopathological characteristics of patients with PDAC with or without a history of other primary malignancies. A total of 102 patients with surgically treated PDAC that presented with or without a history of other primary malignancies were retrospectively analyzed. A total of 25 patients (24.5%) had a history of other primary malignancies (age, with history of other primary malignancy vs. without, 74.2 vs. 68.9 years; P=0.005) and the reason for consultation (P<0.001) differed significantly between the groups with a history of other primary malignancies [HoM(+)] and without a history of other primary malignancies [HoM(-)]. Incidental indications during malignancy follow-up was the most common reason for the diagnosis of PDAC in the HoM(+) group. Conversely, there were no significant differences in the resectability (P=0.645), complete resection rate (P=0.774) and final stage (P=0.474) between the two groups. Disease-free survival was also not significantly different between the two groups (P=0.184). However, overall survival was significantly poorer in the HoM(+) group compared with the HoM(-) group (P=0.003). A history of other primary malignancies was also an independent predictor of poor overall survival (hazard ratio, 2.416; 95% confidence interval, 1.324-4.406; P=0.004). In conclusion, patients with PDAC and a history of other primary malignancies had significantly poorer overall survival than their counterparts, despite no differences in disease-free survival.

Somatic Mutation Profiling in the Liquid Biopsy and Clinical Analysis of Hereditary and Familial Pancreatic Cancer Cases Reveals KRAS Negativity and a Longer Overall Survival

Simple Summary

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis. KRAS mutations occur in up to 95% of cases and render the tumor resistant to many types of therapy. Therefore, these patients are treated with traditional cytotoxic agents, according to guidelines. The familial or hereditary form of the disease accounts for up to 10–15% of cases. We hypothesized that hereditary and Familial Pancreatic Cancer cases (H/FPC) have a distinct tumor specific mutation profile due to the presence of pathogenic germline mutations and we used circulating free DNA (cfDNA) in plasma to assess this hypothesis. H/FPC cases were mainly KRAS mutation negative and harbored tumor specific mutations that are potential treatment targets in the clinic. Thus, we conclude that cases with a hereditary or familial background can be treated with newer and more effective agents that may ultimately improve their overall survival.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) presents many challenges in the clinic and there are many areas for improvement in diagnostics and patient management. The five-year survival rate is around 7.2% as the majority of patients present with advanced disease at diagnosis that is treatment resistant. Approximately 10–15% of PDAC cases have a hereditary basis or Familial Pancreatic Cancer (FPC). Here we demonstrate the use of circulating free DNA (cfDNA) in plasma as a prognostic biomarker in PDAC. The levels of cfDNA correlated with disease status, disease stage, and overall survival. Furthermore, we show for the first time via BEAMing that the majority of hereditary or familial PDAC cases (around 84%) are negative for a KRAS somatic mutation. In addition, KRAS mutation negative cases harbor somatic mutations in potentially druggable genes such as KIT, PDGFR, MET, BRAF, and PIK3CA that could be exploited in the clinic. Finally, familial or hereditary cases have a longer overall survival compared to sporadic cases (10.2 vs. 21.7 months, respectively). Currently, all patients are treated the same in the clinic with cytotoxic agents, although here we demonstrate that there are different subtypes of tumors at the genetic level that could pave the way to personalized treatment.

Interpreting Sequence Variation in PDAC-Predisposing Genes Using a Multi-Tier Annotation Approach Performed at the Gene, Patient, and Cohort Level

We investigated germline variation in pancreatic ductal adenocarcinoma (PDAC) predisposition genes in 535 patients, using a custom-built panel and a new complementary bioinformatic approach. Our panel assessed genes belonging to DNA repair, cell cycle checkpoints, migration, and preneoplastic pancreatic conditions. Our bioinformatics approach integrated annotations of variants by using data derived from both germline and somatic references. This integrated approach with expanded evidence enabled us to consider patterns even among private mutations, supporting a functional role for certain alleles, which we believe enhances individualized medicine beyond classic gene-centric approaches. Concurrent evaluation of three levels of evidence, at the gene, sample, and cohort level, has not been previously done. Overall, we identified in PDAC patient germline samples, 12% with mutations previously observed in pancreatic cancers, 23% with mutations previously discovered by sequencing other human tumors, and 46% with mutations with germline associations to cancer. Non-polymorphic protein-coding pathogenic variants were found in 18.4% of patient samples. Moreover, among patients with metastatic PDAC, 16% carried at least one pathogenic variant, and this subgroup was found to have an improved overall survival (22.0 months versus 9.8; p=0.008) despite a higher pre-treatment CA19-9 level (p=0.02). Genetic alterations in DNA damage repair genes were associated with longer overall survival among patients who underwent resection surgery (92 months vs. 46; p=0.06). ATM alterations were associated with more frequent metastatic stage (p = 0.04) while patients with BRCA1 or BRCA2 alterations had improved overall survival (79 months vs. 39; p=0.05). We found that mutations in genes associated with chronic pancreatitis were more common in non-white patients (p<0.001) and associated with longer overall survival (52 months vs. 26; p=0.004), indicating the need for greater study of the relationship among these factors. More than 90% of patients were found to have variants of uncertain significance, which is higher than previously reported. Furthermore, we generated 3D models for selected mutant proteins, which suggested distinct mechanisms underlying their dysfunction, likely caused by genetic alterations. Notably, this type of information is not predictable from sequence alone, underscoring the value of structural bioinformatics to improve genomic interpretation. In conclusion, the variation in PDAC predisposition genes appears to be more extensive than anticipated. This information adds to the growing body of literature on the genomic landscape of PDAC and brings us closer to a more widespread use of precision medicine for this challenging disease.

Inherited predisposition to pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is projected to be the second leading cause of cancer death in the US by 2030. There are multiple germline pathogenic variants and cancer syndromes associated with an increased risk of PDAC. Precision treatment, informed by germline genetic testing and molecular tumor analysis, can optimize therapeutic regimens and outcomes for those diagnosed with PDAC. As a result, the National Comprehensive Cancer Network currently recommends genetic testing for all newly diagnosed PDAC patients given the clinical implications for treatment but also for the identification of at-risk family members who can benefit from pancreatic cancer screening and other cancer prevention strategies. This article reviews inherited risk factors for the development of PDAC and current screening strategies for the early detection of PDAC in high-risk populations.

Identification of New Genes Involved in Germline Predisposition to Early-Onset Gastric Cancer

The genetic cause for several families with gastric cancer (GC) aggregation is unclear, with marked relevance in early-onset patients. We aimed to identify new candidate genes involved in GC germline predisposition. Whole-exome sequencing (WES) of germline samples was performed in 20 early-onset GC patients without previous germline mutation identified. WES was also performed in nine tumor samples to analyze the somatic profile using SigProfilerExtractor tool. Sequencing germline data were filtered to select those variants with plausible pathogenicity, rare frequency and previously involved in cancer. Then, a manual filtering was performed to prioritize genes according to current knowledge and function. These genetic variants were prevalidated with Integrative Genomics Viewer 2.8.2 (IGV). Subsequently, a further selection step was carried out according to function and information obtained from tumor samples. After IGV and selection step, 58 genetic variants in 52 different candidate genes were validated by Sanger sequencing. Among them, APC, FAT4, CTNND1 and TLR2 seem to be the most promising genes because of their role in hereditary cancer syndromes, tumor suppression, cell adhesion and Helicobacter pylori recognition, respectively. These encouraging results represent the open door to the identification of new genes involved in GC germline predisposition.

Research Progress of Pancreas-Related Microorganisms and Pancreatic Cancer

Pancreatic cancer is one of the most common digestive system cancers. Early diagnosis is difficult owing to the lack of specific symptoms and reliable biomarkers. The cause of pancreatic cancer remains ambiguous. Smoking, drinking, new-onset diabetes, and chronic pancreatitis have been proven to be associated with the occurrence of pancreatic cancer. In recent years, a large number of studies have clarified that a variety of microorganisms colonized in pancreatic cancer tissues are also closely related to the occurrence and development of pancreatic cancer, and the specific mechanisms include inflammatory induction, immune regulation, metabolism, and microenvironment changes caused by microorganism. The mechanism of action of the pancreatic colonized microbiome in the tumor microenvironment, as well as immunotherapy approaches require further study in order to find more evidence to explain the complex relationship between the pancreatic colonized microbiome and PDAC. Relevant studies targeting the microbiome may provide insight into the mechanisms of PDAC development and progression, improving treatment effectiveness and overall patient prognosis. In this article, we focus on the research relating to the microorganisms colonized in pancreatic cancer tissues, including viruses, bacteria, and fungi. We also highlight the microbial diversity in the occurrence, invasion, metastasis, treatment, and prognosis of pancreatic cancer in order to elucidate its significance in the early diagnosis and new therapeutic treatment of pancreatic cancer, which urgently need to be improved in clinical practice. The elimination or increase in diversity of the pancreatic microbiome is beneficial for prolonging the survival of PDAC patients, improving the response to chemotherapy drugs, and reducing tumor burden. The colonization of microorganisms in the pancreas may become a new hotspot in the diagnosis and treatment of pancreatic cancer.

Should This Patient Be Screened for Pancreatic Cancer? : Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Because pancreatic cancer is typically advanced at the time of diagnosis, it has a very low 5-year survival rate and may become the second leading cause of cancer death in the United States. A screening program to find early-stage pancreatic cancer is needed but has been challenging to develop because of the lack of an effective screening test. In 2019, the U.S. Preventive Services Task Force performed an evidence review and updated its guidance, confirming its 2004 "D" recommendation against routine screening for average-risk patients. Here, 2 experts review the updated guideline and recent evidence and discuss whether a patient with a family history of pancreatic cancer should undergo screening.

Can Elderly Patients With Pancreatic Cancer Gain Survival Advantages Through More Radical Surgeries? A SEER-Based Analysis

Background and Aims

In recent years, the best treatment method for pancreatic cancer in elderly patients has remained controversial. Surgery is the main treatment modality for pancreatic cancer. This study aimed to determine whether elderly patients with pancreatic cancer can gain survival advantages through more active and radical surgical treatment and evaluate the best treatment method and potential prognostic factors.

Methods

From the Surveillance, Epidemiology, and End Results program (SEER) database, 10,557 elderly patients (aged ≥65 years) with pancreatic cancer were included as Cohort 1, and Propensity Score Matching (PSM) evaluation was performed to generate Cohort 2 (424 pairs). Overall Survival (OS) and Cause-Specific Survival (CSS) were determined using Kaplan-Meier survival curves, and differences were assessed using the Log-rank test. Multivariate logistic regression analysis and the forest plot of hazard ratio (HR) was made to assess the association between potential prognostic factors, including surgery and different surgical methods, and survival in elderly patients.

Results

We identified 10,557 eligible patients with pancreatic cancer, who formed Cohort 1. The total OS and CSS in the surgery group were significantly higher than those in the non-surgery group (P < 0.001). Age, stage (AJCC 8th), grade, lymph node metastasis, radiation, chemotherapy, and surgical methods were independent factors affecting the prognosis of elderly patients. In Cohort 2, Total pancreatectomy (Total PT) had the lowest risk ratio (HR = 0.31, P < 0.001) and longest median CSS (18.000 months), while Extension Total pancreatectomy (Ex-Total PT, HR = 0.34, P < 0.001) showed the lower median CSS (17.000 months) and median OS (14.000 months). Partial pancreatectomy (Partial PT, HR = 0.46, P < 0.001) showed the lowest median CSS (13.000 months) and median OS (12.000 months), although they were still higher than the median CSS (6.000 months) and median OS (5.000 months) in the non-surgery group.

Conclusions

Based on the SEER database, surgical treatment is an independent prognostic factor in elderly patients with pancreatic cancer. Compared with other surgical methods, Total PT can offer elderly patients the best survival advantages. However, Ex-Total PT, a more radical method, does not seem to be the best treatment option for the survival and benefit of elderly patients.

Genetic Counseling for Hereditary Gastric and Pancreatic Cancer in High-Risk Gastrointestinal Cancer Clinics: An Effective Strategy

The identification of high-risk groups of gastric (GC) and pancreatic adenocarcinoma (PC) due to a hereditary basis could imply a benefit in the affected families by establishing personalized preventive strategies. We aimed at assessing the diagnostic yield of GC/PC hereditary syndromes in individuals evaluated based on specific clinical criteria. In total, 77 unrelated individuals (45 from GC group/32 from PC group) were recruited: 51 (66.2%) cancer diagnosis ≤60 years, 3 (4%) with personal history of GC/PC and other cancer and 23 (29.8%) due to family history. Immunohistochemical analysis of DNA mismatch repair proteins was performed in 38 (49.3%) available tumors, being pathological in one (2%) GC. A genetic analysis was performed if clinical criteria of hereditary syndrome were fulfilled, identifying a mutation in 10/22 (45.5%) families [7/16 (43.7%) with GC and 3/6 (50%) with PC] and 19 (24.7%) fulfilled criteria of familial cancer. Diagnosis of cancer <40 years and personal history of other cancers were independent risk factors of a hereditary syndrome [OR:11.3 (95%IC 1.9–67); p = 0.007 and OR:17.4 (95% IC 2.5–119.9); p = 0.004; respectively]. The selection of patients based on clinical criteria leads to high diagnostic yield, detecting a causative germline mutation in almost half of the cases; therefore, both meticulous genetic counseling and use of multi-gen panels is crucial.