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Familial adenomatous polyposis (FAP) is an autosomal dominant syndrome responsible for 1% of colorectal cancers (CRCs). Up to 90% of classic FAPs are caused by inactivating mutations in APC, and mosaicism has been previously reported in 20% of de novo cases, usually linked to milder phenotypic manifestations. This study aimed to explore the prevalence of mosaicism in 11 unsolved cases of classic FAP and to evaluate the diagnostic yield of somatic testing. Paired samples of colorectal polyps, tumors, and/or mucosa were analyzed using a custom next-generation sequencing panel targeting 15 polyposis and CRC-predisposing genes. Whenever possible, the extension of mosaicism to blood or sperm was also examined. Of 11 patients with classic adenomatous polyposis, a mosaic pathogenic variant in APC was identified in 7 (64%). No other altered genes were identified. In two of seven patients (29%), mosaicism was found restricted to colonic tissues, whereas in five of seven patients (71%), it was extended to the blood. Germline affectation was confirmed in one patient. We report the first analysis at a somatic level of 15 genes associated with CRC susceptibility, which highlights the role of APC mosaicism in classic FAP etiology. The results further reinforce the importance of testing target tissues when blood test results are negative.

Purpose To identify predictors of patient acceptance of non-in-person cancer genetic visits before and after the COVID-19 pandemic and assess the preferences of health-care professionals. Methods Prospective multicenter cohort study (N = 578, 1 February 2018–20 April 2019) and recontacted during the COVID-19 lockdown in April 2020. Health-care professionals participated in May 2020. Association of personality traits and clinical factors with acceptance was assessed with multivariate analysis. Results Before COVID-19, videoconference was more accepted than telephone-based visits (28% vs. 16% pretest, 30% vs. 19% post-test). Predictors for telephone visits were age (pretest, odds ratio [OR] 10-year increment = 0.79; post-test OR 10Y = 0.78); disclosure of panel testing (OR = 0.60), positive results (OR = 0.52), low conscientiousness group (OR = 2.87), and post-test level of uncertainty (OR = 0.93). Predictors for videoconference were age (pretest, OR 10Y = 0.73; post-test, OR 10Y = 0.75), educational level (pretest: OR = 1.61), low neuroticism (pretest, OR = 1.72), and post-test level of uncertainty (OR = 0.96). Patients’ reported acceptance for non-in-person visits after COVID-19 increased to 92% for the pretest and 85% for the post-test. Health-care professionals only preferred non-in-person visits for disclosure of negative results (83%). Conclusion These new delivery models need to recognize challenges associated with age and the psychological characteristics of the population and embrace health-care professionals’ preferences.

RNA analyses are a potent tool to identify spliceogenic effects of DNA variants, although they are time-consuming and cannot always be performed. We present splicing assays of 20 variants that represent a variety of mutation types in 10 hereditary cancer genes and attempt to incorporate these results into American College of Medical Genetics and Genomics (ACMG) classification guidelines. Sixteen single-nucleotide variants, 3 exon duplications, and 1 single-exon deletion were selected and prioritized by in silico algorithms. RNA was extracted from short-term lymphocyte cultures to perform RT-PCR and Sanger sequencing, and allele-specific expression was assessed whenever possible. Aberrant transcripts were detected in 14 variants (70%). Variant interpretation was difficult, especially comparing old classification standards to generic ACMG guidelines and a proposal was devised to weigh functional analyses at RNA level. According to the ACMG guidelines, only 12 variants were reclassified as pathogenic/likely pathogenic because the other two variants did not gather enough evidence. This study highlights the importance of RNA studies to improve variant classification. However, it also indicates the challenge of incorporating these results into generic ACMG guidelines and the need to refine these criteria gene specifically. Nevertheless, 60% of variants were reclassified, thus improving genetic counseling and surveillance for carriers of these variants.

Context Lynch syndrome (LS) is the most common inherited colorectal and endometrial cancer syndrome, caused by germline mutations in DNA mismatch repair (MMR) genes. It is also characterized by an increased risk of other tumors with lower prevalence, such as adrenal cortical carcinoma (ACC), an endocrine tumor with an incidence of Evidence Acquisition The objective of this study is to determine the prevalence of ACC in a Spanish LS cohort and their molecular and histological characteristics. This retrospective study includes 634 patients from 220 LS families registered between 1999 and 2018. Evidence Synthesis During the follow-up period, 3 patients were diagnosed with ACC (0.47%); all were carriers of a MSH2 germline mutation. The 3 ACC patients presented loss of expression of MSH2 and MSH6 proteins. One tumor analysis showed loss of heterozygosity of the MSH2 wildtype allele. Our findings support previous data that considered ACC as a LS spectrum tumor. Conclusion MMR protein immunohistochemistry screening could be an efficient strategy to detect LS in patients with ACC.

Colorectal (CRC) and endometrial cancer (EC) are the most common types of cancer in Lynch syndrome (LS). Risk reducing surgeries (RRS) might impact cancer incidence and mortality. Our objectives were to evaluate cumulative incidences of CRC, gynecological cancer and all-cause mortality after RRS in LS individuals.Retrospective analysis of 976 LS carriers from a single-institution registry. Primary endpoints were cumulative incidence at 75 years of cancer (metachronous CRC in 425 individuals; EC and ovarian cancer (OC) in 531 individuals) and all-cause mortality cumulative incidence, comparing extended (ES) vs. segmental surgery (SS) in the CRC cohort and risk reducing gynecological surgery (RRGS) vs. surveillance in the gynecological cohort.Cumulative incidence at 75 years of metachronous CRC was 12.5% vs. 44.7% (RRS in LS reduces the incidence of metachronous CRC and gynecological neoplasms, also indicating a reduction in all-cause mortality cumulative incidence in females undergoing RRGS.

RNA analyses are a potent tool to identify spliceogenic effects of DNA variants, although they are time-consuming and cannot always be performed. We present splicing assays of 20 variants that represent a variety of mutation types in 10 hereditary cancer genes and attempt to incorporate these results into American College of Medical Genetics and Genomics (ACMG) classification guidelines. Sixteen single-nucleotide variants, 3 exon duplications, and 1 single-exon deletion were selected and prioritized by in silico algorithms. RNA was extracted from short-term lymphocyte cultures to perform RT-PCR and Sanger sequencing, and allele-specific expression was assessed whenever possible. Aberrant transcripts were detected in 14 variants (70%). Variant interpretation was difficult, especially comparing old classification standards to generic ACMG guidelines and a proposal was devised to weigh functional analyses at RNA level. According to the ACMG guidelines, only 12 variants were reclassified as pathogenic/likely pathogenic because the other two variants did not gather enough evidence. This study highlights the importance of RNA studies to improve variant classification. However, it also indicates the challenge of incorporating these results into generic ACMG guidelines and the need to refine these criteria gene specifically. Nevertheless, 60% of variants were reclassified, thus improving genetic counseling and surveillance for carriers of these variants.

Síndrome de Lynch; Panell de gens del càncer; Epimutació Síndrome de Lynch; Panel de genes del cáncer; Epimutación Lynch syndrome; Cancer genes panel; Epimutation The causal mechanism for cancer predisposition in Lynch-like syndrome (LLS) remains unknown. Our aim was to elucidate the constitutional basis of mismatch repair (MMR) deficiency in LLS patients throughout a comprehensive (epi)genetic analysis. One hundred and fifteen LLS patients harboring MMR-deficient tumors and no germline MMR mutations were included. Mutational analysis of 26 colorectal cancer (CRC)-associated genes was performed. Pathogenicity of MMR variants was assessed by splicing and multifactorial likelihood analyses. Genome-wide methylome analysis was performed by the Infinium Human Methylation 450K Bead Chip. The multigene panel analysis revealed the presence of two MMR gene truncating mutations not previously found. Of a total of 15 additional MMR variants identified, five -present in 6 unrelated individuals- were reclassified as pathogenic. In addition, 13 predicted deleterious variants in other CRC-predisposing genes were found in 12 probands. Methylome analysis detected one constitutional MLH1 epimutation, but no additional differentially methylated regions were identified in LLS compared to LS patients or cancer-free individuals. In conclusion, the use of an ad-hoc designed gene panel combined with pathogenicity assessment of variants allowed the identification of deleterious MMR mutations as well as new LLS candidate causal genes. Constitutional epimutations in non-LS-associated genes are not responsible for LLS. This work was funded by the Spanish Ministry of Economy and Competitiveness and cofunded by FEDER funds -a way to build Europe- (grants SAF2012-33636, SAF2015-68016-R and SAF2016-80888-R), CIBERONC, RTICC Network (RD12/0036/0031 and RD12/0036/0008), the Spanish Association Against Cancer (AECC) (080253), the Government of Catalonia (grant 2014SGR338, 2017SGR1282 and PERIS SLT002/16/0037), Fundación Mutua Madrileña (grant AP114252013). We thank CERCA Programme for institutional support. ED was supported by a grant from the Spanish Ministry of Economy and Competitiveness. The AECC fellowship to MG-A. AF was supported by a grant from the Catalonian Health Department (SLT002/16/00409). FM was supported by CIBERONC. The Mexican National Council for Science and Technology (CONACyT) fellowship to GV.

We read with interest the work by Yan et al published in Gut .1 The serrated (hyperplastic) polyposis syndrome (SPS) is a heterogeneous disease defined by the presence of multiple serrated polyps throughout the colon,2 causing an increased risk (16%) of colorectal cancer (CRC).3 By performing whole-exome sequencing in 20 SPS families, Gala et al identified a germline mutation, c.338C>A (p.R113*), in the RING-type E3 ubiquitin ligase RNF43, an inhibitor of the Wnt pathway, in two independent families.4 The c.394C>T (p.R132*) mutation was subsequently identified in two SPS-affected members of one family, supporting a causal role in SPS.5 In the study by Yan et al whole-exome sequence analysis of four SPS families identified a deleterious germline mutation, c.953–1G>A (p.E318fs), in six members of one family, five fulfilling the WHO criteria for SPS.1 Buchanan et al assessed the mutation status of RNF43 in 74 selected SPS families, identifying two rare missense variants, c.443C>G (p.A148G) and c.640C>G (p.L214V), predicted deleterious by in silico algorithms, in two families. No carriers of p.R113* or p.R132* were detected in 221 additional patients with SPS.6 Mutation screening of RNF43 was carried out by Sanger sequencing in …

The multifactorial likelihood analysis method has demonstrated utility for quantitative assessment of variant pathogenicity for multiple cancer syndrome genes. Independent data types currently incorporated in the model for assessing BRCA1 and BRCA2 variants include clinically calibrated prior probability of pathogenicity based on variant location and bioinformatic prediction of variant effect, co-segregation, family cancer history profile, co-occurrence with a pathogenic variant in the same gene, breast tumor pathology, and case-control information. Research and clinical data for multifactorial likelihood analysis were collated for 1,395 BRCA1/2 predominantly intronic and missense variants, enabling classification based on posterior probability of pathogenicity for 734 variants: 447 variants were classified as (likely) benign, and 94 as (likely) pathogenic; and 248 classifications were new or considerably altered relative to ClinVar submissions. Classifications were compared with information not yet included in the likelihood model, and evidence strengths aligned to those recommended for ACMG/AMP classification codes. Altered mRNA splicing or function relative to known nonpathogenic variant controls were moderately to strongly predictive of variant pathogenicity. Variant absence in population datasets provided supporting evidence for variant pathogenicity. These findings have direct relevance for BRCA1 and BRCA2 variant evaluation, and justify the need for gene-specific calibration of evidence types used for variant classification., Ohio State University Comprehensive Cancer Center Barretos Cancer Hospital. Grant Number: FINEP ‐ CT‐INFRA (02/2010) Breast Cancer Foundation of New Zealand Canadian Institutes of Health Research. Grant Number: PSR‐SIIRI‐701 Cancer Research UK. Grant Numbers: C8197/A16565, C5047/A8384, C1281/A12014, C12292/A11174, C1287/A10710, C1287/A10118, C1287/A16563, C5047/A10692, C5047/A15007 Department of Defence, USA. Grant Number: W81XWH‐10‐1‐0341 Helsinki University Hospital Research fund Scientific Foundation Asociación Española Contra el Cáncer Leiden University Medical Centre. Grant Number: Grant 30.925 Generalitat de Catalunya. Grant Numbers: PERIS_MedPerCan, URDCat, 2017SGR1282, 2017SGR496 Royal Society of New Zealand Cancer Council Victoria Netherlands Organization for Scientific Research (NWO). Grant Number: Grant 017.008.022 Breast Cancer Research Foundation Cancer Foundation of Western Australia EU H2020. Grant Number: 634935 Fundación Mutua Madrileña Seventh Framework Programme. Grant Numbers: 634935, 223175, 633784 Cancer Council South Australia Government of Galicia. Grant Number: Consolidation and structuring program: IN607B Cancer Council Tasmania Italian Association of Cancer Research. Grant Number: 15547 Queensland Cancer Fund AstraZeneca National Institute of Health (USA). Grant Numbers: 1U19 CA148065‐01, CA128978, CA192393, 1U19 CA148537, P50 CA1162091, CA116167, 1U19 CA148112 Newcastle University Dutch Cancer Society KWF. Grant Numbers: KWF/Pink Ribbon‐11704, UL2012‐5649 National Institute for Health Research. Grant Number: Manchester Biomedical Research centre (IS‐BRC‐1215 National Council of Technological and Scientific Development (CNPq) Instituto de Salud Carlos III. Grant Numbers: FIS PI15/00355, FIS PI13/01711, CIBERONC, FIS PI16/01218, PI16/00563 French National Institute of Cancer National Breast Cancer Foundation National Health and Medical Research Council. Grant Numbers: ID1061778, ID1104808 Carlos III National Health Centro de Investigación Biomédica en Red de Enferemdades Raras. Grant Number: ACCI 2016: ER17P1AC7112/2018 Cancer Council NSW Deutsche Krebshilfe. Grant Numbers: (#110837, #70111850 Fondazione Pisa. Grant Number: Grant “Clinical characterization of BRCA 1/2 Mis

Background: Colorectal (CRC) and endometrial cancer (EC) are the most common types of cancer in Lynch syndrome (LS). Risk reducing surgeries (RRS) might impact cancer incidence and mortality. Our objectives were to evaluate cumulative incidences of CRC, gynecological cancer and all-cause mortality after RRS in LS individuals. Methods: Retrospective analysis of 976 LS carriers from a single-institution registry. Primary endpoints were cumulative incidence at 75 years of cancer (metachronous CRC in 425 individuals, EC and ovarian cancer (OC) in 531 individuals) and all-cause mortality cumulative incidence, comparing extended (ES) vs. segmental surgery (SS) in the CRC cohort and risk reducing gynecological surgery (RRGS) vs. surveillance in the gynecological cohort. Results: Cumulative incidence at 75 years of metachronous CRC was 12.5% vs. 44.7% (p = 0.04) and all-cause mortality cumulative incidence was 38.6% vs. 55.3% (p = 0.31), for ES and SS, respectively. Cumulative, incidence at 75 years was 11.2% vs. 46.3% for EC (p = 0.001) and 0% vs. 12.7% for OC (p N/A) and all-cause mortality cumulative incidence was 0% vs. 52.7% (p N/A), for RRGS vs. surveillance, respectively. Conclusions: RRS in LS reduces the incidence of metachronous CRC and gynecological neoplasms, also indicating a reduction in all-cause mortality cumulative incidence in females undergoing RRGS.

In a proportion of patients presenting mismatch repair (MMR)-deficient tumors, no germline MMR mutations are identified, the so-called Lynch-like syndrome (LLS). Recently, MMR-deficient tumors have been associated with germline mutations in POLE and MUTYH or double somatic MMR events. Our aim was to elucidate the molecular basis of MSH2-deficient LS-suspected cases using a comprehensive analysis of colorectal cancer (CRC)-associated genes at germline and somatic level. Fifty-eight probands harboring MSH2-deficient tumors were included. Germline mutational analysis of MSH2 (including EPCAM deletions) and MSH6 was performed. Pathogenicity of MSH2 variants was assessed by RNA analysis and multifactorial likelihood calculations. MSH2 cDNA and methylation of MSH2 and MSH6 promoters were studied. Matched blood and tumor DNA were analyzed using a customized next generation sequencing panel. Thirty-five individuals were carriers of pathogenic or probably pathogenic variants in MSH2 and EPCAM. Five patients harbored 4 different MSH2 variants of unknown significance (VUS) and one had 2 novel MSH6 promoter VUS. Pathogenicity assessment allowed the reclassification of the 4 MSH2 VUS and 6 probably pathogenic variants as pathogenic mutations, enabling a total of 40 LS diagnostics. Predicted pathogenic germline variants in BUB1, SETD2, FAN1 and MUTYH were identified in 5 cases. Three patients had double somatic hits in MSH2 or MSH6, and another 2 had somatic alterations in other MMR genes and/or proofreading polymerases. In conclusion, our comprehensive strategy combining germline and somatic mutational status of CRC-associated genes by means of a subexome panel allows the elucidation of up to 86% of MSH2-deficient suspected LS tumors.

Neurofibromatosis type 2 (NF2) is an autosomal-dominant disorder affecting about 1:33 000 newborns, mainly characterized by the development of tumors of the nervous system and ocular abnormalities. Around 85% of germline NF2 mutations are point mutations. Among them, ∼25% affect splicing and are associated with a variable disease severity. In the context of our NF2 Multidisciplinary Clinics, we have identified a patient fulfilling clinical criteria for the disease and exhibiting a severe phenotype. The patient carries a deep intronic mutation (g. 74409T>A, NG_009057.1) that produces the insertion of a cryptic exon of 167pb in the mature mRNA between exons 13 and 14, resulting in a truncated merlin protein (p.Pro482Profs*39). A mutation-specific antisense phosphorodiamidate morpholino oligomer was designed and used in vitro to effectively restore normal NF2 splicing in patient-derived primary fibroblasts. In addition, merlin protein levels were greatly recovered after morpholino treatment, decreasing patient's fibroblasts in vitro proliferation capacity and restoring cytoeskeleton organization. To our knowledge, this is the first NF2 case caused by a deep intronic mutation in which an in vitro antisense therapeutic approximation has been tested. These results open the possibility of using this approach in vivo for this type of mutation causing NF2.

La Neurofibromatosis tipo 2 (NF2) es una enfermedad minoritaria hereditaria caracterizada por la presentación progresiva de múltiples tumores, especialmente Schwanomas Vestibulares Bilaterales, a partir de la segunda década de vida. Su tratamiento con cirugía o radioterapia no evita la pérdida de audición. El pronóstico es complicado y los pacientes deben enfrentarse al progresivo deterioro de su calidad de vida. Un estudio cualitativo a través de la historia de vida de nuestra informante clave nos permite explorar y comprender su vivencia, afecta de Neurofibromatosis tipo II (NF2), así como conocer sus necesidades y aprender de sus recursos adaptativos.Neurofibromatosis type 2 (NF2) is a minority hereditary disease characterized by the development of multiple tumours, especially bilateral vestibular schwannomas, in young adults. Treatments with surgery or radiotherapy are performed to delay hearing loss. The prognosis is complicated and patients face the deterioration of their quality of life. A qualitative study through our key subject's life allows us to explore and understand her experience, as a NF2 sufferer, to identify her needs and to learn about her adaptive measures.

Background and aims: Individuals with tumours showing mismatch repair (MMR) deficiency not linked to germline mutations or somatic methylation of MMR genes have been recently referred as having lynch-like syndrome' (LLS). The genetic basis of these LLS cases is unknown. MUTYH-associated polyposis patients show some phenotypic similarities to Lynch syndrome patients. The aim of this study was to investigate the prevalence of germline MUTYH mutations in a large series of LLS patients. Methods: Two hundred and twenty-five probands fulfilling LLS criteria were included in this study. Screening of MUTYH recurrent mutations, whole coding sequencing and a large rearrangement analysis were undertaken. Age, sex, clinical, pathological and molecular characteristics of tumours including KRAS mutations were assessed. Results: We found a prevalence of 3.1% of MAP syndrome in the whole series of LLS (7/225) and 3.9% when only cases fulfilling clinical criteria were considered (7/178). Patients with MUTYH biallelic mutations had more adenomas than monoallelic (P = 0.02) and wildtype patients (P < 0.0001). Six out of nine analysed tumours from six biallelic MUTYH carriers harboured KRAS-p.G12C mutation. This mutation was found to be associated with biallelic MUTYH germline mutation when compared with reported series of unselected colorectal cancer cohorts (P < 0.0001). Conclusions: A proportion of unexplained LLS cases is caused by biallelic MUTYH mutations. The obtained results further justify the inclusion of MUTYH in the diagnostic strategy for Lynch syndrome-suspected patients. (C) 2014 Elsevier Ltd. All rights reserved.

e17071Background: Since the approval of the PARP inhibitor olaparib, the TFGT indications for OC have dramatically increased. Furthermore, several guidelines include genetic testing for all non-muc...

La Neurofibromatosis tipo 2 (NF2) es una enfermedad minoritaria hereditaria caracterizada por la presentación progresiva de múltiples tumores, especialmente Schwanomas Vestibulares Bilaterales, a partir de la segunda década de vida. Su tratamiento con cirugía o radioterapia no evita la pérdida de audición. El pronóstico es complicado y los pacientes deben enfrentarse al progresivo deterioro de su calidad de vida. Un estudio cualitativo a través de la historia de vida de nuestra informante clave nos permite explorar y comprender su vivencia, afecta de Neurofibromatosis tipo II (NF2), así como conocer sus necesidades y aprender de sus recursos adaptativos. Neurofibromatosis type 2 (NF2) is a minority hereditary disease characterized by the development of multiple tumours, especially bilateral vestibular schwannomas, in young adults. Treatments with surgery or radiotherapy are performed to delay hearing loss. The prognosis is complicated and patients face the deterioration of their quality of life. A qualitative study through our key subject's life allows us to explore and understand her experience, as a NF2 sufferer, to identify her needs and to learn about her adaptive measures.