Familial pancreatic cancer

Pancreatic cancer risk to siblings of probands in bilineal cancer settings

PURPOSE

Pancreatic cancer (PC) risk is increased in families, but PC risk and risk perception have been understudied when both parents have cancer.

METHODS

An unbiased method defining cancer triads (proband with PC and both parents with cancer) in a prospective registry estimated risk of PC to probands' siblings in triad group 1 (no parent with PC), group 2 (1 parent with PC), and group 3 (both parents with PC). We estimated standardized incidence ratios (SIRs) using a Surveillance, Epidemiology, and End Results (SEER) reference. We also estimated the risk when triad probands carried germline pathogenic/likely pathogenic variants in any of the 6 PC-associated genes (ATM, BRCA1, BRCA2, CDKN2A, MLH1, and TP53). PC risk perception/concern was surveyed in siblings and controls.

RESULTS

Risk of PC was higher (SIR = 3.5; 95% CI = 2.2-5.2) in 933 at-risk siblings from 297 triads. Risk increased by triad group: 2.8 (95% CI = 1.5-4.5); 4.5 (95% CI = 1.6-9.7); and 21.2 (95% CI = 4.3-62.0). SIR in variant-negative triads was 3.0 (95% CI = 1.6-5.0), whereas SIR in variant-positive triads was 10.0 (95% CI = 3.2-23.4). Siblings' perceived risk/concern of developing PC increased by triad group.

CONCLUSION

Sibling risks were 2.8- to 21.2-fold higher than that of the general population. Positive variant status increased the risk in triads. Increasing number of PC cases in a triad was associated with increased concern and perceived PC risk.

Beyond BRCA: The Emerging Significance of DNA Damage Response and Personalized Treatment in Pancreatic and Prostate Cancer Patients

The BRCA1/2 germline and/or somatic pathogenic variants (PVs) are key players in the hereditary predisposition and therapeutic response for breast, ovarian and, more recently, pancreatic and prostate cancers. Aberrations in other genes involved in homologous recombination and DNA damage response (DDR) pathways are being investigated as promising targets in ongoing clinical trials. However, DDR genes are not routinely tested worldwide. Due to heterogeneity in cohort selection and dissimilar sequencing approaches across studies, neither the burden of PVs in DDR genes nor the prevalence of PVs in genes in common among pancreatic and prostate cancer can be easily quantified. We aim to contextualize these genes, altered in both pancreatic and prostate cancers, in the DDR process, to summarize their hereditary and somatic burden in different studies and harness their deficiency for cancer treatments in the context of currently ongoing clinical trials. We conclude that the inclusion of DDR genes, other than BRCA1/2, shared by both cancers considerably increases the detection rate of potentially actionable variants, which are triplicated in pancreatic and almost doubled in prostate cancer. Thus, DDR alterations are suitable targets for drug development and to improve the outcome in both pancreatic and prostate cancer patients. Importantly, this will increase the detection of germline pathogenic variants, thereby patient referral to genetic counseling.

SEOM-GETTHI clinical guideline for the practical management of molecular platforms (2021)

The improvement of molecular alterations in cancer as well as the development of technology has allowed us to bring closer to clinical practice the determination of molecular alterations in the diagnosis and treatment of cancer. The use of multidetermination platforms is spreading in most Spanish hospitals. The objective of these clinical practice guides is to review their usefulness, and establish usage guidelines that guide their incorporation into clinical practice.

Pancreatic Cancer with Mutation in BRCA1/2, MLH1, and APC Genes: Phenotype Correlation and Detection of a Novel Germline BRCA2 Mutation

Pancreatic ductal adenocarcinoma (PDAC) is the seventh leading cause of cancer death worldwide; most of cases are sporadic, however about 5% to 10% report a hereditary predisposition. Several hereditary syndromes have been associated with familial pancreatic cancer (FPC) onset, including hereditary breast and ovarian cancer syndrome (HBOC), Lynch syndrome (LS), Familial atypical multiple mole melanoma (FAMMM), Familial adenomatous polyposis (FAP), Li-Fraumeni syndrome (LFS), Peutz-Jeghers syndrome (PJS), and Hereditary pancreatitis (HP).The aim of this study was to determine the mutational status of a cohort of 56 HBOC families, 7 LS families, 3 FAP and FAMMM families, and 1 LFS family with at least one case of PDAC. Mutation analysis of BRCA1/2, ATM, CHEK2, PALB2, RAD51C, RAD51D, NBN, CDH1, TP53, MLH1, MSH2, MSH6, and PMS2 genes, showedmutation in BRCA1/2, MLH1, and APC genes. We founda high mutation rate in patients belong HBOC and LS families, with a percentage of 28.6% in both syndromes and prevalence in HBOC of BRCA2 mutations with one case of double mutation in BRCA2 gene. In FAP family, we found a pathogenic mutation in APC gene in 1/3 families. We observed an early onset of PDAC and a lower survival in PDAC patients belonging to mutated families, while no evidence of possible pancreatic cancer cluster regions was found. Moreover, we identified a novel BRCA2 germline mutation, c.5511delT (p.Phe1837LeufsX3), not reported in any database, that segregated with disease in HBOC patients. Mutational analysis was extended to family membersof mutated patients, both healthy and cancer affected, which revealed 23 unaffected family members that inherited the proband's mutation. Although correlative by its nature, the presence of a BRCA mutation in PDAC patients may have benefits in terms of optimized treatment and longer outcome.

Predictive factors of survival in patients with borderline resectable pancreatic cancer who received neoadjuvant therapy

BACKGROUND/OBJECTIVES

This study aimed to develop the prognostic score (PS) based on clinical factors to stratify the prognosis in borderline resectable pancreatic cancer (BRPC) patients treated with neoadjuvant therapy (NAT).

METHODS

This retrospective study included 57 BRPC patients who received NAT between April 2012 and December 2017. A score was assigned to each prognostic factor available before and after NAT, according to their β coefficients.

RESULTS

Multivariate analysis identified the following six prognostic factors, and scores were assigned as follows: being a familial PC patient (HR 4.98, p = 0.029), post-NAT CA19-9 ≥37 U/ml (HR 3.08, p = 0.020), reduction rate of CA19-9 <70% (HR 3.71, p = 0.008), pre-NAT neutrophil-to-lymphocyte ratio ≥2.8 (HR 4.32, p = 0.003), and non-resection (HR 3.98, p = 0.009) were scored as 1; and post-NAT albumin-to-globulin ratio <1.33 (HR 8.31, p < 0.001) was scored as 2. The PS was calculated by summing the scores assigned to each prognostic factor. Patients were then classified into three risk groups (low- [0-1 points], moderate- [2-3 points], and high-risk [4-6 points] groups). Median overall survival in the low-, moderate-, and high-risk groups were not reached, 37.5 months, and 11.8 months, respectively, and there were significant differences in survival among the three groups (p < 0.01 in each group).

CONCLUSIONS

This study showed that the PS may be useful for predicting the prognosis of BRPC patients treated with NAT.

Functional neuroanatomy of arithmetic in monolingual and bilingual adults and children

Prior studies on the brain bases of arithmetic have not focused on (or even described) their participants' language backgrounds. Yet, unlike monolinguals, early bilinguals have the capacity to solve arithmetic problems in both of their two languages. This raises the question whether this ability, or any other experience that comes with being bilingual, affects brain activity for arithmetic in bilinguals relative to monolinguals. Here, we used functional magnetic resonance imaging to compare brain activity in 44 English monolinguals and 44 Spanish-English early bilinguals, during the solving of arithmetic problems in English. We used a factorial design to test for a main effect of bilingual Language Experience. Based on the known modulating roles of arithmetic operation and age, we used two arithmetic tasks (addition and subtraction) and studied two age groups (adults and children). When collapsing across operations and age, we found broad bilateral activation for arithmetic in both the monolingual group and the bilingual group. However, an analysis of variance revealed that there was no effect of Language Experience, nor an interaction of Language Experience with Operation or Age Group. Bayesian analyses within regions of interest chosen for their role in arithmetic further supported the finding of no effect of Language Experience on brain activity underlying arithmetic. We conclude that early bilingualism does not influence the functional neuroanatomy of simple arithmetic.

Treatment opportunities and future perspectives for pancreatic cancer patients with germline BRCA1-2 pathogenic variants

Personalized treatments and predictive biomarkers of pancreatic cancer (PDAC) are still lacking. Recently germline mutations in BRCA 1 and 2 genes, leading to homologous repair deficiency, have emerged as new targets for more specific and effective therapies, exploiting the increased susceptibility to platinum salts and PARP inhibitors. In addition to BRCA, pathogenic variants in PALB2 and in other genes involved in the DNA damage response pathway (DDR) represent potential targets, as well as their respective somatic alterations. This enlarged molecularly-selected population sharing the BRCAness phenotype, is expected to show a higher sensibility to a number of DNA damaging agents and DDR inhibitors. However, the possibility of new therapeutic opportunities for DDR defective PDAC patients has to face the lack of solid evidence about the proper type and timing of targeted-treatments, the potential combination strategies and most importantly, the lack of informations on the functional impact of each specific pathogenic variant on the DDR pathway. This review summarizes the current and near-future options for the clinical management of PDAC patients harboring a DDR deficiency, analyzing the state of the art of the indications of platinum salts and other cytotoxic agents in the advanced and early stage PDAC, the development of PARP inhibitors and the rational for new combinations with immunotherapy and cycle checkpoint inhibitors, as well as the strategy to overcome the development of resistance over treatments.

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.

A systematic review of the prevalence of germline pathogenic variants in patients with pancreatic cancer

The genetics of pancreatic ductal adenocarcinoma (PDAC) is complex with patients reported to harbor germline pathogenic variants (PVs) in many different genes. PDAC patients with familial pancreatic cancer (FPC) are more likely to carry germline PVs but there is no consensus main gene involved in FPC. We performed a systematic review of publications from PubMed and Scopus reporting PVs in patients with FPC, sporadic pancreatic cancer (SPC) and unselected cohorts of PDAC patients undergoing genetic testing and calculated a cumulative prevalence of PVs for each gene evaluated across these three groups of patients. When available, variants in the selected publications were reclassified according to the American College of Medical Genetics and Genomics classification system and used for prevalence calculations if classified as pathogenic or likely pathogenic. We observed an increased prevalence of PVs in FPC compared to SPC or unselected PDAC patients for most of the 41 genes reported. The genes with the highest prevalence of carriers of PVs in FPC were ATM, BRCA2, and CDKN2A. BRCA2 and ATM showed the highest prevalence of PVs in both SPC and unselected PDAC cohorts. Several genes with the highest prevalence of PVs are involved in breast and ovarian cancer suggesting strong overlap with underlying genetics in these disorders but no single gene was predominant. More research is needed to further understand the risk of PDAC associated with these many diverse genes.

Cohort profile and heritability assessment of familial pancreatic cancer: a nation-wide study

BACKGROUND

Familial Pancreatic Cancer (FPC) is responsible for up to 10% of all cases of pancreatic ductal adenocarcinoma (PDAC). Individuals predisposed for FPC have an estimated lifetime risk of 16-39% of developing PDAC. While heritability of PDAC has been estimated to be 36% in a Nordic twin study, no heritability estimate specific on FPC has been reported.

METHODS

A national cohort of Danish families with predisposition for FPC is currently included in a screening program for PDAC at Odense University Hospital. Family members included in the screening program were interviewed for pedigree data including: cases of PDAC among first-degree relatives (FDRs) and number of affected/unaffected siblings. Heritability for FPC in the predisposed families was assessed by doubling the estimated intra-class correlation coefficient (ICC) from a random intercept logistic model fitted to data on FDRs.

RESULTS

Among families with predisposition for FPC, 83 cases of PDAC were identified. The median age at diagnosis of PDAC was 66 years, and median time from diagnosis to death was 7.6 months. A total of 359 individuals were found as unaffected FDRs of the 83 PDAC cases. The retrieved FDRs included a total of 247 individuals in sibship and 317 individuals in parent-offspring relatedness. We estimated an ICC of 0.25, corresponding to a narrow sense additive heritability estimate of 0.51 in the FPC family cohort.

CONCLUSION

We have established a nation-wide cohort of FPC families to facilitate clinical and genetic studies on FPC. The estimated heritability of 51% prominently underlines a strong genetic background of FPC.

Screening for pancreatic cancer: a review for general clinicians

Pancreatic cancer (PC) is an exceptionally lethal malignancy with increasing incidence and mortality worldwide. One of the principal challenges in the treatment of PC is that the diagnosis is usually made at a late stage when potentially curative surgical resection is no longer an option. General clinicians including internists and family physicians are well positioned to identify high-risk individuals and refer them to centers with expertise in PC screening and treatment where screening modalities can be employed. Here, we provide an up-to-date review of PC precursor lesions, epidemiology, and risk factors to empower the general clinician to recognize high-risk patients and employ risk reduction strategies. We also review current screening guidelines and modalities and preview progress that is being made to improve screening tests and biomarkers. It is our hope that this review article will empower the general clinician to understand which patients need to be screened for PC, strategies that may be used to reduce PC risk, and which screening modalities are available in order to diminish the lethality of PC.

Pancreas in Hereditary Syndromes: Cross-sectional Imaging Spectrum

A wide spectrum of hereditary syndromes predispose patients to distinct pancreatic abnormalities, including cystic lesions, recurrent pancreatitis, ductal adenocarcinoma, nonductal neoplasms, and parenchymal iron deposition. While pancreatic exocrine insufficiency and recurrent pancreatitis are common manifestations in cystic fibrosis and hereditary pancreatitis, pancreatic cysts are seen in von Hippel-Lindau disease, cystic fibrosis, autosomal dominant polycystic kidney disease, and McCune-Albright syndrome. Ductal adenocarcinoma can be seen in many syndromes, including Peutz-Jeghers syndrome, familial atypical multiple mole melanoma syndrome, Lynch syndrome, hereditary breast and ovarian cancer syndrome, Li-Fraumeni syndrome, and familial pancreatic cancer syndrome. Neuroendocrine tumors are commonly seen in multiple endocrine neoplasia type 1 syndrome and von Hippel-Lindau disease. Pancreatoblastoma is an essential component of Beckwith-Wiedemann syndrome. Primary hemochromatosis is characterized by pancreatic iron deposition. Pancreatic pathologic conditions associated with genetic syndromes exhibit characteristic imaging findings. Imaging plays a pivotal role in early detection of these conditions and can positively affect the clinical outcomes of those at risk for pancreatic malignancies. Awareness of the characteristic imaging features, imaging-based screening protocols, and surveillance guidelines is crucial for radiologists to guide appropriate patient management. ^©RSNA, 2021.

Comprehensive analysis of DNA damage repair genes reveals pathogenic variants beyond BRCA and suggests the need for extensive genetic testing in pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) is a major cause of cancer death. In an effort to improve treatment strategies and outcomes, DNA damage repair (DDR) pathways have been introduced as a new target in PC and in other cancers, through the exploitation of synthetic lethality. Furthermore, genes involved in DDR are among the major determinants of cancer susceptibility. In addition to the well-known BRCA1 and BRCA2 genes, a plethora of other targets in the same pathways are now emerging.

METHODS

We analyzed samples from 60 patients, affected by PC and already tested for BRCA, using a panel with 24 other cancer susceptibility genes.

RESULTS

We detected 8 pathogenic or likely pathogenic mutations (13.3% of samples analyzed), 4 of which were found in non-BRCA genes (2 in ATM, 1 each in PALB2 and RAD50). Furthermore, 4 pathogenic or likely pathogenic mutations were found in patients without a personal or familial history of cancer.

CONCLUSIONS

Our results suggest that genetic testing with a comprehensive gene panel should be perfomed in all patients with PC, in order to allow screening for PC and other gene-related cancers in all at risk family members and to assess patients' eligibility for emerging therapeutic options.

BRCA mutated pancreatic cancer: A change is coming

Pancreatic cancer remains a leading cause of cancer-related death with few available therapies for advanced disease. Recently, patients with germline BRCA mutations have received increased attention due to advances in the management of BRCA mutated ovarian and breast tumors. Germline BRCA mutations significantly increase risk of developing pancreatic cancer and can be found in up to 8% of patients with sporadic pancreatic cancer. In patients with germline BRCA mutations, platinum-based chemotherapies and poly (ADP-ribose) polymerase inhibitors are effective treatment options which may offer survival benefits. This review will focus on the molecular biology, epidemiology, and management of BRCA-mutated pancreatic cancer. Furthermore, we will discuss future directions for this area of research and promising active areas of research.

The implication of liquid biopsies to predict chemoresistance in pancreatic cancer

Pancreatic cancer is one of the most aggressive diseases among solid tumors. Most patients are diagnosed with advanced or metastatic disease and are characterized by poor chemosensitivity. Therefore, earlier diagnosis and novel therapeutic possibilities for pancreatic cancer patients are urgently needed. Liquid biopsy is an emerging technology that allows the noninvasive sampling of tumor material. Nowadays, liquid biopsy has shown promising results as diagnostic, prognostic and predictive biomarkers, but it has not yet been universally adopted into regular use by clinicians. In this review, we describe different components of liquid biopsy, especially circulating tumor cells, circulating tumor DNA and exosomes and their potential clinical utility for pancreatic cancer patients.

A rare germline CDKN2A variant (47T>G; p16-L16R) predisposes carriers to pancreatic cancer by reducing cell cycle inhibition

Germline mutations in CDKN2A, encoding the tumor suppressor p16, are responsible for a large proportion of familial melanoma cases and also increase risk of pancreatic cancer. We identified four families through pancreatic cancer probands that were affected by both cancers. These families bore a germline missense variant of CDKN2A (47T>G), encoding a p16-L16R mutant protein associated with high cancer occurrence. Here, we investigated the biological significance of this variant. When transfected into p16-null pancreatic cancer cells, p16-L16R was expressed at lower levels than wild-type (WT) p16. In addition, p16-L16R was unable to bind CDK4 or CDK6 compared with WT p16, as shown by coimmunoprecipitation assays and also was impaired in its ability to inhibit the cell cycle, as demonstrated by flow cytometry analyses. In silico molecular modeling predicted that the L16R mutation prevents normal protein folding, consistent with the observed reduction in expression/stability and diminished function of this mutant protein. We isolated normal dermal fibroblasts from members of the families expressing WT or L16R proteins to investigate the impact of endogenous p16-L16R mutant protein on cell growth. In culture, p16-L16R fibroblasts grew at a faster rate, and most survived until later passages than p16-WT fibroblasts. Further, western blotting demonstrated that p16 protein was detected at lower levels in p16-L16R than in p16-WT fibroblasts. Together, these results suggest that the presence of a CDKN2A (47T>G) mutant allele contributes to an increased risk of pancreatic cancer as a result of reduced p16 protein levels and diminished p16 tumor suppressor function.

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.

Lead-Time Trajectory of CA19-9 as an Anchor Marker for Pancreatic Cancer Early Detection

BACKGROUND & AIMS

There is substantial interest in liquid biopsy approaches for cancer early detection among subjects at risk, using multi-marker panels. CA19-9 is an established circulating biomarker for pancreatic cancer; however, its relevance for pancreatic cancer early detection or for monitoring subjects at risk has not been established.

METHODS

CA19-9 levels were assessed in blinded sera from 175 subjects collected up to 5 years before diagnosis of pancreatic cancer and from 875 matched controls from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. For comparison of performance, CA19-9 was assayed in blinded independent sets of samples collected at diagnosis from 129 subjects with resectable pancreatic cancer and 275 controls (100 healthy subjects; 50 with chronic pancreatitis; and 125 with noncancerous pancreatic cysts). The complementary value of 2 additional protein markers, TIMP1 and LRG1, was determined.

RESULTS

In the PLCO cohort, levels of CA19-9 increased exponentially starting at 2 years before diagnosis with sensitivities reaching 60% at 99% specificity within 0 to 6 months before diagnosis for all cases and 50% at 99% specificity for cases diagnosed with early-stage disease. Performance was comparable for distinguishing newly diagnosed cases with resectable pancreatic cancer from healthy controls (64% sensitivity at 99% specificity). Comparison of resectable pancreatic cancer cases to subjects with chronic pancreatitis yielded 46% sensitivity at 99% specificity and for subjects with noncancerous cysts, 30% sensitivity at 99% specificity. For prediagnostic cases below cutoff value for CA19-9, the combination with LRG1 and TIMP1 yielded an increment of 13.2% in sensitivity at 99% specificity (P = .031) in identifying cases diagnosed within 1 year of blood collection.

CONCLUSION

CA19-9 can serve as an anchor marker for pancreatic cancer early detection applications.

Germinal BRCA1-2 pathogenic variants (gBRCA1-2pv) and pancreatic cancer: epidemiology of an Italian patient cohort

OBJECTIVE

Germline BRCA1-2 pathogenic variants (gBRCApv) increase the risk of pancreatic cancer and predict for response to platinating agents and poly(ADP-ribose) polymerase inhibitors. Data on worldwide gBRCApv incidence among pancreatic ductal adenocarcinoma (PDAC) patients are sparse and describe a remarkable geographic heterogeneity. The aim of this study is to analyze the epidemiology of gBRCApv in Italian patients.

MATERIALS AND METHODS

Patients of any age with pancreatic adenocarcinoma, screened within 3 months from diagnosis for gBRCApv in Italian oncologic centers systematically performing tests without any selection. For the purposes of our analysis, breast, ovarian, pancreas, and prostate cancer in a patient's family history was considered as potentially BRCA-associated. Patients or disease characteristics were examined using the χ2 test or Fisher's exact test for qualitative variables and the Student's t-test or Mann-Whitney test for continuous variables, as appropriate.

RESULTS

Between June 2015 and May 2020, 939 patients were tested by 14 Italian centers; 492 (52%) males, median age 62 years (range 28-87), 569 (61%) metastatic, 273 (29%) with a family history of potentially BRCA-associated cancers. gBRCA1-2pv were found in 76 patients (8.1%; 9.1% in metastatic; 6.4% in non-metastatic). The gBRCA2/gBRCA1 ratio was 5.4 : 1. Patients with gBRCApv were younger compared with wild-type (59 versus 62 years, P = 0.01). The gBRCApv rate was 17.1% among patients <40 years old, 10.4% among patients 41-50 years old, 9.2% among patients 51-60 years old, 6.7% among patients aged 61-70 years, and 6.2% among patients >70 years old (none out of 94 patients >73 years old). gBRCApv frequency in 845 patients <74 years old was 9%. Patients with/without a family history of potentially BRCA-associated tumors had 14%/6% mutations.

CONCLUSION

Based on our findings of a gBRCApv incidence higher than expected in a real-life series of Italian patients with incident PDAC, we recommend screening all PDAC patients <74 years old, regardless of family history and stage, due to the therapeutic implications and cancer risk prevention in patients' relatives.

The influence of familial pancreatic cancer on postoperative outcome in pancreatic cancer: relevance to adjuvant chemotherapy

BACKGROUND

Familial pancreatic cancer (FPC) is defined as a family in which at least two first-degree relatives have pancreatic cancer (PC). The prognostic significance of PC in an FPC family after surgery is not fully understood.

METHODS

This was a retrospective study of 427 patients who underwent pancreatectomy for pancreatic ductal adenocarcinoma between January 2008 and December 2016. PC patients who also had at least one first-degree relative with PC were defined as FPC patients. The associations between recurrence and clinicopathological characteristics were analyzed for both FPC and non-FPC patients.

RESULTS

FPC patients accounted for 31 of the 427 (7.3%) patients. Recurrence occurred in 72.1% of the total cohort and in 87.1% of the 31 FPC patients. Multivariate analysis showed that being an FPC patient was an independent predictor for relapse-free survival (RFS) (hazard ratio [HR] 1.52, P = 0.038). Although univariate analysis revealed that being an FPC patient was significantly associated with poorer overall survival (OS) (P < 0.001), multivariate analysis showed that being an FPC patient was not an independent predictor for OS (P = 0.164). Dichotomization of the 427 patients into those who received (n = 317: 17 FPC and 300 non-FPC patients) and did not receive (n = 110: 14 FPC and 96 non-FPC patients) adjuvant chemotherapy revealed that being an FPC patient was an independent predictor for RFS (HR 2.50, P < 0.001) and OS (HR 2.30, P = 0.003) only for patients who received adjuvant chemotherapy.

CONCLUSIONS

This study has shown that being an FPC patient is a significant prognostic indicator for PC patients who undergo resection and receive adjuvant chemotherapy.

The Impact of Clinical and Pathological Features on Intraductal Papillary Mucinous Neoplasm Recurrence After Surgical Resection: Long-Term Follow-Up Analysis

OBJECTIVE

This study aimed to identify risk factors for recurrence after pancreatic resection for intraductal papillary mucinous neoplasm (IPMN).

SUMMARY BACKGROUND DATA

Long-term follow-up data on recurrence after surgical resection for IPMN are currently lacking. Previous studies have presented mixed results on the role of margin status in risk of recurrence after surgical resection.

METHODS

A total of 126 patients that underwent resection for noninvasive IPMN were followed for a median of 9.5 years. Dedicated pathological and radiological reviews were performed to correlate clinical and pathological features (including detailed pathological features of the parenchymal margin) with recurrence after surgical resection. In addition, in a subset of 32 patients with positive margins, we determined the relationship between the margin and original IPMN using driver gene mutations identified by next-generation sequencing.

RESULTS

Family history of pancreatic cancer and high-grade IPMN was identified as risk factors for recurrence in both uni- and multivariate analysis (adjusted hazard ratio 3.05 and 1.88, respectively). Although positive margin was not significantly associated with recurrence in our cohort, the size and grade of the dysplastic focus at the margin were significantly correlated with recurrence in margin-positive patients. Genetic analyses showed that the neoplastic epithelium at the margin was independent from the original IPMN in at least 9 of 32 cases (28%). The majority of recurrences (74%) occurred after 3 years, and a significant minority (32%) occurred after 5 years.

CONCLUSION

Sustained postoperative surveillance for all patients is indicated, particularly those with risk factors such has family history and high-grade dysplasia.

A Transcriptome-Wide Association Study Identifies Candidate Susceptibility Genes for Pancreatic Cancer Risk

Pancreatic cancer is among the most well-characterized cancer types, yet a large proportion of the heritability of pancreatic cancer risk remains unclear. Here, we performed a large transcriptome-wide association study to systematically investigate associations between genetically predicted gene expression in normal pancreas tissue and pancreatic cancer risk. Using data from 305 subjects of mostly European descent in the Genotype-Tissue Expression Project, we built comprehensive genetic models to predict normal pancreas tissue gene expression, modifying the UTMOST (unified test for molecular signatures). These prediction models were applied to the genetic data of 8,275 pancreatic cancer cases and 6,723 controls of European ancestry. Thirteen genes showed an association of genetically predicted expression with pancreatic cancer risk at an FDR ≤ 0.05, including seven previously reported genes (INHBA, SMC2, ABO, PDX1, RCCD1, CFDP1, and PGAP3) and six novel genes not yet reported for pancreatic cancer risk [6q27: SFT2D1 OR (95% confidence interval (CI), 1.54 (1.25-1.89); 13q12.13: MTMR6 OR (95% CI), 0.78 (0.70-0.88); 14q24.3: ACOT2 OR (95% CI), 1.35 (1.17-1.56); 17q12: STARD3 OR (95% CI), 6.49 (2.96-14.27); 17q21.1: GSDMB OR (95% CI), 1.94 (1.45-2.58); and 20p13: ADAM33 OR (95% CI): 1.41 (1.20-1.66)]. The associations for 10 of these genes (SFT2D1, MTMR6, ACOT2, STARD3, GSDMB, ADAM33, SMC2, RCCD1, CFDP1, and PGAP3) remained statistically significant even after adjusting for risk SNPs identified in previous genome-wide association study. Collectively, this analysis identified novel candidate susceptibility genes for pancreatic cancer that warrant further investigation. SIGNIFICANCE: A transcriptome-wide association analysis identified seven previously reported and six novel candidate susceptibility genes for pancreatic cancer risk.

A Transcriptome-Wide Association Study Identifies Novel Candidate Susceptibility Genes for Pancreatic Cancer

BACKGROUND

Although 20 pancreatic cancer susceptibility loci have been identified through genome-wide association studies in individuals of European ancestry, much of its heritability remains unexplained and the genes responsible largely unknown.

METHODS

To discover novel pancreatic cancer risk loci and possible causal genes, we performed a pancreatic cancer transcriptome-wide association study in Europeans using three approaches: FUSION, MetaXcan, and Summary-MulTiXcan. We integrated genome-wide association studies summary statistics from 9040 pancreatic cancer cases and 12 496 controls, with gene expression prediction models built using transcriptome data from histologically normal pancreatic tissue samples (NCI Laboratory of Translational Genomics [n = 95] and Genotype-Tissue Expression v7 [n = 174] datasets) and data from 48 different tissues (Genotype-Tissue Expression v7, n = 74-421 samples).

RESULTS

We identified 25 genes whose genetically predicted expression was statistically significantly associated with pancreatic cancer risk (false discovery rate < .05), including 14 candidate genes at 11 novel loci (1p36.12: CELA3B; 9q31.1: SMC2, SMC2-AS1; 10q23.31: RP11-80H5.9; 12q13.13: SMUG1; 14q32.33: BTBD6; 15q23: HEXA; 15q26.1: RCCD1; 17q12: PNMT, CDK12, PGAP3; 17q22: SUPT4H1; 18q11.22: RP11-888D10.3; and 19p13.11: PGPEP1) and 11 at six known risk loci (5p15.33: TERT, CLPTM1L, ZDHHC11B; 7p14.1: INHBA; 9q34.2: ABO; 13q12.2: PDX1; 13q22.1: KLF5; and 16q23.1: WDR59, CFDP1, BCAR1, TMEM170A). The association for 12 of these genes (CELA3B, SMC2, and PNMT at novel risk loci and TERT, CLPTM1L, INHBA, ABO, PDX1, KLF5, WDR59, CFDP1, and BCAR1 at known loci) remained statistically significant after Bonferroni correction.

CONCLUSIONS

By integrating gene expression and genotype data, we identified novel pancreatic cancer risk loci and candidate functional genes that warrant further investigation.

Building towards Precision Oncology for Pancreatic Cancer: Real-World Challenges and Opportunities

The advent of next-generation sequencing (NGS) has provided unprecedented insight into the molecular complexity of pancreatic ductal adenocarcinoma (PDAC). This has led to the emergence of biomarker-driven treatment paradigms that challenge empiric treatment approaches. However, the growth of sequencing technologies is outpacing the development of the infrastructure required to implement precision oncology as routine clinical practice. Addressing these logistical barriers is imperative to maximize the clinical impact of molecular profiling initiatives. In this review, we examine the evolution of precision oncology in PDAC, spanning from germline testing for cancer susceptibility genes to multi-omic tumor profiling. Furthermore, we highlight real-world challenges to delivering precision oncology for PDAC, and propose strategies to improve the generation, interpretation, and clinical translation of molecular profiling data.

Negative Regulation of Serine Threonine Kinase 11 (STK11) through miR-100 in Head and Neck Cancer

BACKGROUND

Serine Threonine Kinase 11 (STK11), also known as LKB1, is a tumor suppressor gene that regulates several biological processes such as apoptosis, energetic metabolism, proliferation, invasion, and migration. During malignant progression, different types of cancer inhibit STK11 function by mutation or epigenetic inactivation. In Head and Neck Cancer, it is unclear what mechanism is involved in decreasing STK11 levels. Thus, the present work aims to determine whether STK11 expression might be regulated through epigenetic or post-translational mechanisms.

METHODS

Expression levels and methylation status for STK11 were analyzed in 59 cases of head and neck cancer and 10 healthy tissue counterparts. Afterward, we sought to identify candidate miRNAs exerting post-transcriptional regulation of STK11. Then, we assessed a luciferase gene reporter assay to know if miRNAs directly target STK11 mRNA. The expression levels of the clinical significance of mir-100-3p, -5p, and STK11 in 495 HNC specimens obtained from the TCGA database were further analyzed. Finally, the Kaplan-Meier method was used to estimate the prognostic significance of the miRNAs for Overall Survival, and survival curves were compared through the log-rank test.

RESULTS

STK11 was under-expressed, and its promoter region was demethylated or partially methylated. miR-17-5p, miR-106a-5p, miR-100-3p, and miR-100-5p could be negative regulators of STK11. Our experimental data suggested evidence that miR-100-3p and -5p were over-expressed in analyzed tumor patient samples. Luciferase gene reporter assay experiments showed that miR-100-3p targets and down-regulates STK11 mRNA directly. With respect to overall survival, STK11 expression level was significant for predicting clinical outcomes.

CONCLUSION

This is, to our knowledge, the first report of miR-100-3p targeting STK11 in HNC. Together, these findings may support the importance of regulation of STK11 through post-transcriptional regulation in HNC and the possible contribution to the carcinogenesis process in this neoplasia.

Early detection of pancreatic cancer

PURPOSE OF REVIEW

Pancreatic cancer is the third leading cause of cancer death and with a dismal 5-year survival of 10%. Poor survival of pancreatic cancer is mostly due to its presentation and diagnosis at a late stage. The present article aims to update clinicians with recent progress in the field of early detection of pancreatic cancer.

RECENT FINDINGS

Pancreatic cancer screening is not recommended in the general population due to its low prevalence. In this review, we discuss high-risk groups for pancreatic cancer, including inherited predisposition to pancreatic cancer, new-onset diabetes, mucinous pancreatic cyst, and chronic pancreatitis. We discuss methods of enrichment of high-risk groups with clinical models using electronic health records and biomarkers. We also discuss improvements in imaging modalities and emerging role of machine learning and artificial intelligence in the field of imaging and biomarker to aid in early identification of pancreatic cancer.

SUMMARY

There are still vast challenges in the field of early detection of pancreatic cancer. We need to develop noninvasive prediagnostic validated biomarkers for longitudinal surveillance of high-risk individuals and imaging modalities that can identify pancreatic cancer early.

Multidisciplinary standards of care and recent progress in pancreatic ductal adenocarcinoma

Despite tremendous gains in the molecular understanding of exocrine pancreatic cancer, the prognosis for this disease remains very poor, largely because of delayed disease detection and limited effectiveness of systemic therapies. Both incidence rates and mortality rates for pancreatic cancer have increased during the past decade, in contrast to most other solid tumor types. Recent improvements in multimodality care have substantially improved overall survival, local control, and metastasis-free survival for patients who have localized tumors that are amenable to surgical resection. The widening gap in prognosis between patients with resectable and unresectable or metastatic disease reinforces the importance of detecting pancreatic cancer sooner to improve outcomes. Furthermore, the developing use of therapies that target tumor-specific molecular vulnerabilities may offer improved disease control for patients with advanced disease. Finally, the substantial morbidity associated with pancreatic cancer, including wasting, fatigue, and pain, remains an under-addressed component of this disease, which powerfully affects quality of life and limits tolerance to aggressive therapies. In this article, the authors review the current multidisciplinary standards of care in pancreatic cancer with a focus on emerging concepts in pancreatic cancer detection, precision therapy, and survivorship.

Informing patients about their mutation tests: CDKN2A c.256G>A in melanoma as an example

Background

When germline mutations are suspected as causal in cancer, patient DNA may be sequenced to detect variants in relevant genes. If a particular mutation has not been reported in reliable family studies, genetic counselors are facing a dilemma of appropriately informing patients. Many sequencing facilities provide an interpretation of the findings based on the available sequence databases or on prediction tools that are curated from bioinformatics and mechanistic datasets. The counseling dilemma is exacerbated if the pedigree data are not informative but the in silico predictions suggest pathogenicity.

Methods

We present here a real world example of the c.256G > A CDKN2A variant, which was detected in one melanoma patient where two siblings were diagnosed with melanoma in situ. We investigated a detailed family history of the affected siblings in order to survey probability of the cancer risks within the context to this mutation.

Results

This c.256G > A CDKN2A variant was detected in one of the brothers and in the melanoma-free mother while the other brother in the family tested negative. The variant had been previously described in one patient from a melanoma family. In the family under investigation, the mother’s 16 first-and second-degree relatives had survived past the median onset age for melanoma and none presented melanoma. We tested the variant using multiple bioinformatic tools that all predicted deleteriousness of the variant. The genetic counseling report to the melanoma patient stated that the CDKN2A variant was ‘likely pathogenic’ and the disease was defined as ‘likely hereditary melanoma’.

Conclusions

The pedigree data showed at the most a low penetrance variant, which, if taken into consideration, might have altered the provided diagnosis. When dealing with ‘practically’ unknown variants the counselors would be advised to incorporate a detailed family history rather than basing predictions on functionality provided by sequencing facilities.

Epigenetic Landscape in Pancreatic Ductal Adenocarcinoma: On the Way to Overcoming Drug Resistance?

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive solid malignancies due to the rapid rate of metastasis and high resistance to currently applied cancer therapies. The complex mechanism underlying the development and progression of PDAC includes interactions between genomic, epigenomic, and signaling pathway alterations. In this review, we summarize the current research findings on the deregulation of epigenetic mechanisms in PDAC and the influence of the epigenome on the dynamics of the gene expression changes underlying epithelial–mesenchymal transition (EMT), which is responsible for the invasive phenotype of cancer cells and, therefore, their metastatic potential. More importantly, we provide an overview of the studies that uncover potentially actionable pathways. These studies provide a scientific basis to test epigenetic drug efficacy in synergy with other anticancer therapies in future clinical trials, in order to reverse acquired therapy resistance. Thus, epigenomics has the potential to generate relevant new knowledge of both a biological and clinical impact. Moreover, the potential, hurdles, and challenges of predictive biomarker discoveries will be discussed, with a special focus on the promise of liquid biopsies.

BRCA testing in a genomic diagnostics referral center during the COVID-19 pandemic

The first person-to-person transmission of the 2019-novel coronavirus in Italy on 21 February 2020 led to an infection chain that represents one of the largest known COVID-19 outbreaks outside Asia. Hospitals have been forced to reorganized their units in response to prepare for an unforeseen healthcare emergency. In this context, our laboratory (Molecular and Genomic Diagnostics Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS) re-modulated its priorities by temporarily interrupting most of the molecular tests guaranteeing only those considered “urgent” and not postponable. In particular, this paper details changes regarding the execution of germline BRCA (gBRCA) testing in our laboratory. A substantial reduction in gBRCA testing (about 60%) compared to the first 2 months of the current year was registered, but the requests have not been reset. The requesting physicians were mainly gynaecologists and oncologists. These evidences further emphasize the new era of gBRCA testing in the management of cancer patients and confirms definitively the integration of gBRCA testing/Next Generation Sequencing (NGS) into clinical oncology. Finally, a re-organization of gBRCA testing in our Unit, mainly related to delayed and reduced arrival of tests was necessary, ensuring, however, a high-quality standard and reliability, mandatory for gBRCA testing in a clinical setting.

Proteostasis Dysregulation in Pancreatic Cancer

The most common form of pancreatic cancer, pancreatic ductal adenocarcinoma (PDAC), has a dismal 5-year survival rate of less than 5%. Radical surgical resection, in combination with adjuvant chemotherapy, provides the best option for long-term patient survival. However, only approximately 20% of patients are resectable at the time of diagnosis, due to locally advanced or metastatic disease. There is an urgent need for the identification of new, specific, and more sensitive biomarkers for diagnosis, prognosis, and prediction to improve the treatment options for pancreatic cancer patients. Dysregulation of proteostasis is linked to many pathophysiological conditions, including various types of cancer. In this review, we report on findings relating to the main cellular protein degradation systems, the ubiquitin-proteasome system (UPS) and autophagy, in pancreatic cancer. The expression of several components of the proteolytic network, including E3 ubiquitin-ligases and deubiquitinating enzymes, are dysregulated in PDAC, which accounts for approximately 90% of all pancreatic malignancies. In the future, a deeper understanding of the emerging role of proteostasis in pancreatic cancer has the potential to provide clinically relevant biomarkers and new strategies for combinatorial therapeutic options to better help treat the patients.

Hereditary and Sporadic Pancreatic Ductal Adenocarcinoma: Current Update on Genetics and Imaging

Pancreatic ductal adenocarcinoma (PDAC) is a genetically heterogeneous, biologically aggressive malignancy with a uniformly poor prognosis. While most pancreatic cancers arise sporadically, a small subset of PDACs develop in patients with hereditary and familial predisposition. Detailed studies of the rare hereditary syndromes have led to identification of specific genetic abnormalities that contribute to malignancy. For example, germline mutations involving BRCA1, BRCA2, PRSS1, and mismatch repair genes predispose patients to PDAC. While patients with Lynch syndrome develop a rare "medullary" variant of adenocarcinoma, intraductal papillary mucinous tumors are observed in patients with McCune-Albright syndrome. It is now well established that PDACs originate via a multistep progression from microscopic and macroscopic precursors due to cumulative genetic abnormalities. Improved knowledge of tumor genetics and oncologic pathways has contributed to a better understanding of tumor biology with attendant implications on diagnosis, management, and prognosis. In this article, the genetic landscape of PDAC and its precursors will be described, the hereditary syndromes that predispose to PDAC will be reviewed, and the current role of imaging in screening and staging assessment, as well as the potential role of molecular tumor-targeted imaging for evaluation of patients with PDAC and its precursors, will be discussed. Keywords: Abdomen/GI, Genetic Defects, Oncology, Pancreas Supplemental material is available for this article. © RSNA, 2020.

PARP inhibitors in pancreatic cancer: molecular mechanisms and clinical applications

Pancreatic cancer is a highly lethal disease with a poor prognosis, and existing therapies offer only limited effectiveness. Mutation gene sequencing has shown several gene associations that may account for its carcinogenesis, revealing a promising research direction. Poly (ADP-ribose) polymerase (PARP) inhibitors target tumor cells with a homologous recombination repair (HRR) deficiency based on the concept of synthetic lethality. The most prominent target gene is BRCA, in which mutations were first identified in breast cancer and ovarian cancer. PARP inhibitors can trap the PARP-1 protein at a single-stranded break/DNA lesion and disrupt its catalytic cycle, ultimately leading to replication fork progression and consequent double-strand breaks. For tumor cells with BRCA mutations, HRR loss would result in cell death. Pancreatic cancer has also been reported to have a strong relationship with BRCA gene mutations, which indicates that pancreatic cancer patients may benefit from PARP inhibitors. Several clinical trials are being conducted and have begun to yield results. For example, the POLO (Pancreatic Cancer Olaparib Ongoing) trial has demonstrated that the median progression-free survival was observably longer in the olaparib group than in the placebo group. However, PARP inhibitor resistance has partially precluded their use in clinical applications, and the major mechanism underlying this resistance is the restoration of HRR. Therefore, determining how to use PARP inhibitors in more clinical applications and how to avoid adverse effects, as well as prognosis and treatment response biomarkers, require additional research. This review elaborates on future prospects for the application of PARP inhibitors in pancreatic cancer.

A comprehensive analysis of candidate genes in familial pancreatic cancer families reveals a high frequency of potentially pathogenic germline variants

BACKGROUND

The 5-year survival rate of patients with pancreatic ductal adenocarcinoma (PDAC) is around 5% due to the fact that the majority of patients present with advanced disease that is treatment resistant. Familial pancreatic cancer (FPC) is a rare disorder that is defined as a family with at least two affected first degree relatives, with an estimated incidence of 4%-10%. The genetic basis is unknown in the majority of families although around 10%-13% of families carry germline mutations in known genes associated with hereditary cancer and pancreatitis syndromes.

METHODS

Panel sequencing was performed of 35 genes associated with hereditary cancer in 43 PDAC cases from families with an apparent hereditary pancreatic cancer syndrome.

FINDINGS

Pathogenic variants were identified in 19% (5/26) of PDAC cases from pure FPC families in the genes MLH1, CDKN2A, POLQ and FANCM. Low frequency potentially pathogenic VUS were also identified in 35% (9/26) of PDAC cases from FPC families in the genes FANCC, MLH1, PMS2, CFTR, APC and MUTYH. Furthermore, an important proportion of PDAC cases harboured more than one pathogenic, likely pathogenic or potentially pathogenic VUS, highlighting the multigene phenotype of FPC.

INTERPRETATION

The genetic basis of familial or hereditary pancreatic cancer can be explained in 21% of families by previously described hereditary cancer genes. Low frequency variants in other DNA repair genes are also present in 35% of families which may contribute to the risk of pancreatic cancer development.

FUNDING

This study was funded by the Instituto de Salud Carlos III (Plan Estatal de I + D + i 2013-2016): ISCIII (PI09/02221, PI12/01635, PI15/02101 and PI18/1034) and co-financed by the European Development Regional Fund ''A way to achieve Europe'' (ERDF), the Biomedical Research Network in Cancer: CIBERONC (CB16/12/00446), Red Temática de investigación cooperativa en cáncer: RTICC (RD12/0036/0073) and La Asociación Española contra el Cáncer: AECC (Grupos Coordinados Estables 2016).

Familial Pancreatic Cancer and Surveillance of High-Risk Individuals

Family history of pancreatic cancer (PC) is a risk factor for PC development, and the risk level correlates with the number of affected families. A case of PC with ≥1 PC cases in the first-degree relative is broadly defined as familial pancreatic cancer (FPC) and accounts for 5% to 10% of total PC cases. FPC possesses several epidemiological, genetic and clinicopathological aspects that are distinct from those of conventional PCs. In Western countries, FPC registries have been established since the 1990s, and high-risk individuals are screened to detect early PCs. For the pharmacotherapy of FPC, especially in cases with germline pathogenic BRCA mutations, regimens using platinum and poly (ADP-ribose) polymerase inhibitor have recently been studied for their effectiveness. To date, the concept of FPC has prevailed in Western countries, and it has begun to infiltrate into Eastern countries. As the genetic background and environmental conditions vary in association with ethnicity and living area, we need to establish our own FPC registries and accumulate data in Asian countries.

Murine models for familial pancreatic cancer: Histopathology, latency and drug sensitivity among cancers of Palb2, Brca1 and Brca2 mutant mouse strains

Alterations of the PALB2 tumor suppressor gene have been identified in familial breast, ovarian and pancreatic cancer cases. PALB2 cooperates with BRCA1/2 proteins through physical interaction in initiation of homologous recombination, in maintenance of genome integrity following DNA double-strand breaks. To determine if the role of PALB2 as a linker between BRCA1 and BRCA2 is critical for BRCA1/2-mediated tumor suppression, we generated Palb2 mouse pancreatic cancer models and compared tumor latencies, phenotypes and drug responses with previously generated Brca1/2 pancreatic cancer models. For development of Palb2 pancreatic cancer, we crossed conditional Palb2 null mouse with mice carrying the Kras^G12D; p53^R270H; Pdx1-Cre (KPC) constructs, and these animals were observed for pancreatic tumor development. Individual deletion of Palb2, Brca1 or Brca2 genes in pancreas per se using Pdx1-Cre was insufficient to cause tumors, but it reduced pancreata size. Concurrent expression of mutant Kras^G12D and p53^R270H, with tumor suppressor inactivated strains in Palb2-KPC, Brca1-KPC or Brca2-KPC, accelerated pancreatic ductal adenocarcinoma (PDAC) development. Moreover, most Brca1-KPC and some Palb2-KPC animals developed mucinous cystic neoplasms with PDAC, while Brca2-KPC and KPC animals did not. 26% of Palb2-KPC mice developed MCNs in pancreata, which resemble closely the Brca1 deficient tumors. However, the remaining 74% of Palb2-KPC animals developed PDACs without any cysts like Brca2 deficient tumors. In addition, the number of ADM lesions and immune cells infiltrations (CD3⁺ and F/480⁺) were significantly increased in Brca1-KPC tumors, but not in Brca2-KPC tumors. Interestingly, the level of ADM lesions and infiltration of CD3⁺ or F/480⁺ cells in Palb2-KPC tumors were intermediate between Brca1-KPC and Brca2-KPC tumors. As expected, disruption of Palb2 and Brca1/2 sensitized tumor cells to DNA damaging agents in vitro and in vivo. Altogether, Palb2-KPC PDAC exhibited features observed in both Brca1-KPC and Brca2-KPC tumors, which could be due to its role, as a linker between Brca1 and Brca2.

McCune Albright syndrome is a genetic predisposition to intraductal papillary and mucinous neoplasms of the pancreas associated pancreatic cancer in relation with GNAS somatic mutation - a case report

RATIONALE

Intraductal papillary and mucinous neoplasms of the pancreas (IPMN) are preneoplastic lesions diagnosed with an increasing incidence. Recently, several groups have described, in up to 70% of IPMN, activating mutations of the G-protein alpha stimulatory sub-unit (Gsα subunit) gene (GNAS). GNAS-activating somatic, post-zygotic, mutations are also associated with McCune-Albright syndrome (MCAS) characterized by fibrous dysplasia, precocious puberty, and café-au-lait spots.

PATIENT CONCERNS

We herein report a patient with McCune Albright Syndrome that presented with malignant IPMN and underwent pancreatic resection.

DIAGNOSES AND INTERVENTIONS

Leucocyte and duodenum juice DNA analysis, endoscopically collected from secretin-stimulated pancreatic juice revealed the same (GNAS) activating mutation also found in the invasive pancreatic colloid adenocarcinoma arising from intestinal subtype IPMN.

OUTCOMES

Thirty months after surgery, the patient was alive with recurrence (bone only metastasis).

LESSONS

In this observation, we show that MCAS should be view as a new genetic predisposition to IPMN associated pancreatic cancer, and consequently a targeted screening in this high-risk population might be proposed.

The intricate relationship between diabetes, obesity and pancreatic cancer

Pancreatic cancer is one of the leading determinants of global cancer mortality, and its incidence is predicted to increase, to become in 2030 the second most common cause of cancer-related death. Obesity and diabetes are recognized risk factors for the development of pancreatic cancer. In the last few decades an epidemic of diabetes and obesity has been spreading worldwide, forewarning an increase in incidence of pancreatic cancer. This review considers the most recent literature, covering the multiple molecular axis linking these three pathologies, aiming to draw a more comprehensive view of pancreatic cancer for a better theragnostic stratification of the population.

Pancreatic cancer and melanoma related perceptions and behaviors following disclosure of CDKN2A variant status as a research result

PURPOSE

This study examined whether participants who learned research results related to a germline CDKN2A variant known to be associated with increased risk of pancreatic cancer and malignant melanoma would pursue confirmatory testing and cancer screening, share the genetic information with health care providers and family, and change risk perceptions.

METHODS

Participants were pancreas research registry enrollees whose biological sample was tested in a research laboratory for the variant. In total, 133 individuals were invited to learn a genetic research result and participate in a study about the disclosure process. Perceived cancer risk, screening intentions, and behaviors were assessed predisclosure, immediately postdisclosure, and six months postdisclosure.

RESULTS

Eighty individuals agreed to participate and 63 completed the study. Immediately postdisclosure, carriers reported greater intentions to undergo pancreatic cancer and melanoma screening (p values ≤0.024). Seventy-three percent of carriers (47.5% noncarriers) intended to seek confirmatory testing within six months and 20% (2.5% noncarriers) followed through. All participants shared results with ≥1 family member. More carriers shared results with their health care provider than noncarriers (p = 0.028).

CONCLUSION

Recipients of cancer genetic research results may not follow through with recommended behaviors (confirmatory testing, screening), despite stated intentions. The research result disclosure motivated follow-up behaviors among carriers more than noncarriers.

Surveillance of Individuals with a Family History of Pancreatic Cancer and Inherited Cancer Syndromes: A Strategy for Detecting Early Pancreatic Cancers

A family history of pancreatic cancer (PC) is a risk factor of PC, and risk levels increase as affected families grow in number and/or develop PC at younger ages. Familial pancreatic cancer (FPC) is defined as a client having at least two PC cases in a first degree relatives. In the narrow sense, FPC does not include some inherited cancer syndromes that are known to increase the risks of PC, such as Peutz-Jeghers syndrome (PJS), hereditary pancreatitis (HP), hereditary breast ovarian cancer syndrome (HBOC), and so on. FPC accounts for 5%-10% of total PC diagnoses and is marked by several features in genetic, epidemiological, and clinicopathological findings that are similar to or distinct from conventional PC. Recent advances in genetic medicine have led to an increased ability to identify germline variants of cancer-associated genes. To date, high-risk individuals (HRIs) in many developed countries, including FPC kindreds and inherited cancer syndromes, are screened clinically to detect and treat early-stage PC. This article highlights the concept of FPC and the most recent data on its detection.

[Pancreatic ductal adenocarcinoma]

Pancreatic ductal adenocarcinoma represents the most common malignant tumor of the pancreas. Despite substantial research efforts and gradual diagnostic and therapeutic improvements, its prognosis remains dismal. In accordance with the current German, European, and US guidelines, this CME-article provides a comprehensive review of the disease. In addition, selected up-to-date aspects of epidemiology, etiopathology, genetics, and basic principles of diagnostics and therapy including potential future therapeutic options are discussed.

Referral frequency, attrition rate, and outcomes of germline testing in patients with pancreatic adenocarcinoma

Hereditary predisposition is estimated to account for 10% of all pancreatic cancer cases. However, referral patterns and clinical workflow for germline testing in this disease differ significantly by institution, and many at-risk patients may not undergo appropriate counseling and testing. We undertook an analysis of patients diagnosed with pancreatic cancer (PDAC) who were referred to the Clinical Genetics program of a high-volume academic center over a 3-year period to assess referral frequency, evaluate the yield of germline testing in this selected patient cohort, and elucidate the reasons individuals did not undergo recommended germline testing. Medical records of patients with PDAC referred for genetic counseling between January 2015 and October 2017 were reviewed for demographic, medical/family history, and disease-specific data. If testing did not occur, reasons were documented. Genetic test results were categorized as negative, variants of unknown significance, or established pathogenic mutations. Descriptive statistics included means with standard deviations; associations were analyzed with t test and Fisher's exact test. 32% (137 of 432) of PDAC patients were referred for genetic counseling, but only 64% attended their appointment and 60% ultimately underwent germline testing. Common reasons for attrition included worsening disease severity, lack of patient follow-up, insurance concerns, and logistic/travel challenges. Pathogenic germline mutations were detected in 20% (16 of 82) of patients tested, distributed across races/ethnicities, and significantly associated with younger age and positive family history of breast cancer. PDAC patients frequently do not undergo genetic counseling/germline testing despite appropriate referrals, highlighting a need to develop streamlined processes to engage more patients in testing, especially those with high-risk features.

A region-based gene association study combined with a leave-one-out sensitivity analysis identifies SMG1 as a pancreatic cancer susceptibility gene

Pancreatic adenocarcinoma (PC) is a lethal malignancy that is familial or associated with genetic syndromes in 10% of cases. Gene-based surveillance strategies for at-risk individuals may improve clinical outcomes. However, familial PC (FPC) is plagued by genetic heterogeneity and the genetic basis for the majority of FPC remains elusive, hampering the development of gene-based surveillance programs. The study was powered to identify genes with a cumulative pathogenic variant prevalence of at least 3%, which includes the most prevalent PC susceptibility gene, BRCA2. Since the majority of known PC susceptibility genes are involved in DNA repair, we focused on genes implicated in these pathways. We performed a region-based association study using the Mixed-Effects Score Test, followed by leave-one-out characterization of PC-associated gene regions and variants to identify the genes and variants driving risk associations. We evaluated 398 cases from two case series and 987 controls without a personal history of cancer. The first case series consisted of 109 patients with either FPC (n = 101) or PC at ≤50 years of age (n = 8). The second case series was composed of 289 unselected PC cases. We validated this discovery strategy by identifying known pathogenic BRCA2 variants, and also identified SMG1, encoding a serine/threonine protein kinase, to be significantly associated with PC following correction for multiple testing (p = 3.22x10-7). The SMG1 association was validated in a second independent series of 532 FPC cases and 753 controls (p<0.0062, OR = 1.88, 95%CI 1.17-3.03). We showed segregation of the c.4249A>G SMG1 variant in 3 affected relatives in a FPC kindred, and we found c.103G>A to be a recurrent SMG1 variant associating with PC in both the discovery and validation series. These results suggest that SMG1 is a novel PC susceptibility gene, and we identified specific SMG1 gene variants associated with PC risk.

Next-Generation Sequencing in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is lethal, and the majority of patients present with locally advanced or metastatic disease that is not amenable to cure. Thus, with surgical resection being the only curative modality, it is critical that disease is identified at an earlier stage to allow the appropriate therapy to be applied. Unfortunately, a specific biomarker for early diagnosis has not yet been identified; hence, no screening process exists. Recently, high-throughput screening and next-generation sequencing (NGS) have led to the identification of novel biomarkers for many disease processes, and work has commenced in PDAC. Genomic data generated by NGS not only have the potential to assist clinicians in early diagnosis and screening, especially in high-risk populations, but also may eventually allow the development of personalized treatment programs with targeted therapies, given the large number of gene mutations seen in PDAC. This review introduces the basic concepts of NGS and provides a comprehensive review of the current understanding of genetics in PDAC as related to discoveries made using NGS.