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

Monoallelic PMS2 germline mutations cause 5-15% of Lynch syndrome, a midlife cancer predisposition, whereas biallelic PMS2 mutations cause approximately 60% of constitutional MMR deficiency (CMMRD), a rare childhood cancer syndrome. Recently improved DNA and RNA-based strategies are applied to overcome problematic PMS2 mutation analysis due to the presence of pseudogenes and frequent gene conversion events. Here, we determined PMS2 mutation detection yield and mutation spectrum in a nationwide cohort of 396 probands. Furthermore, we studied concordance between tumor IHC/ MSI (immunohistochemistry/ microsatellite-instability) profile and mutation carrier state. Overall, we found 52 different pathogenic PMS2 variants explaining 121 Lynch syndrome and nine CMMRD patients. In vitro MMR assays suggested pathogenicity for three missense variants. Ninety-one PMS2 mutation carriers (70%) showed isolated loss of PMS2 in their tumors, for 31 (24%) no or inconclusive IHC was available, and eight carriers (6%) showed discordant IHC (presence of PMS2 or loss of both MLH1 and PMS2). Ten cases with isolated PMS2 loss (10%; 10/97) harbored MLH1 mutations. We confirmed that recently improved mutation analysis provides a high yield of PMS2 mutations in patients with isolated loss of PMS2 expression. Application of universal tumor pre-screening methods will however miss some PMS2 germline mutation carriers. This article is protected by copyright. All rights reserved.

Lynch syndrome (LS) patients are at high risk of developing colorectal cancer (CRC). Phenotypic variability might in part be explained by common susceptibility loci identified in Genome Wide Association Studies (GWAS). Previous studies focused mostly on MLH1, MSH2 and MSH6 carriers, with conflicting results. We aimed to determine the role of GWAS SNPs in PMS2 mutation carriers. A cohort study was performed in 507 PMS2 carriers (124 CRC cases), genotyped for 24 GWAS SNPs, including SNPs at 11q23.1 and 8q23.3. Hazard ratios (HRs) were calculated using a weighted Cox regression analysis to correct for ascertainment bias. Discrimination was assessed with a concordance statistic in a bootstrap cross-validation procedure. Individual SNPs only had non-significant associations with CRC occurrence with HRs lower than 2, although male carriers of allele A at rs1321311 (6p21.31) may have increased risk of CRC (HR = 2.1, 95% CI 1.2–3.0). A polygenic risk score (PRS) based on 24 HRs had an HR of 2.6 (95% CI 1.5–4.6) for the highest compared to the lowest quartile, but had no discriminative ability (c statistic 0.52). Previously suggested SNPs do not modify CRC risk in PMS2 carriers. Future large studies are needed for improved risk stratification among Lynch syndrome patients. Electronic supplementary material The online version of this article (10.1007/s10689-017-0061-3) contains supplementary material, which is available to authorized users.

Annual MRI and mammography is recommended for BRCA1/2 mutation carriers to reduce breast cancer mortality. Less intensive screening is advised ≥60 years, although effectiveness is unknown. We identified BRCA1/2 mutation carriers without bilateral mastectomy before age 60 to determine for whom screening ≥60 is relevant, in the Rotterdam Family Cancer Clinic and HEBON: a nationwide prospective cohort study. Furthermore, we compared tumour stage at breast cancer diagnosis between different screening strategies in BRCA1/2 mutation carriers ≥60. Tumours >2 cm, positive lymph nodes, or distant metastases at detection were defined as "unfavourable." Of 548 BRCA1/2 mutation carriers ≥60 years in 2012, 395 (72%) did not have bilateral mastectomy before the age of 60. Of these 395, 224 (57%) had a history of breast or other invasive carcinoma. In 136 BRCA1/2 mutation carriers, we compared 148 breast cancers (including interval cancers) detected ≥60, of which 84 (57%) were first breast cancers. With biennial mammography 53% (30/57) of carcinomas were detected in unfavourable stage, compared to 21% (12/56) with annual mammography (adjusted odds ratio: 4·07, 95% confidence interval [1.79-9.28], p = 0.001). With biennial screening 40% of breast cancers were interval cancers, compared to 20% with annual screening (p = 0.016). Results remained significant for BRCA1 and BRCA2 mutation carriers, and first breast cancers separately. Over 70% of 60-year old BRCA1/2 mutation carriers remain at risk for breast cancer, of which half has prior cancers. When life expectancy is good, continuation of annual breast cancer screening of BRCA1/2 mutation carriers ≥60 is worthwhile.

1539Background: Advances in massively parallel sequencing technologies have made multigene panels affordable and have revolutionized genetic testing for hereditary breast and ovarian cancer. Throug...

Background & Aims Colorectal cancer surveillance guidelines rely on clinicohistologic features of adenomas. Unfortunately, in common practice, recording of these features lacks precision and uniformity, which might hamper appropriate follow-up decisions. Confocal laser endomicroscopy (CLE) is a novel technology that allows real-time in vivo microscopy of the mucosa and provides accurate histopathology. The aims of this study were (1) to define and validate differential features of adenomatous and nonadenomatous colorectal polyps by chromoendoscopy-guided CLE (C-CLE) and (2) to assess predictive value of this technique for diagnosis of colorectal neoplasia. Methods Patients at risk for colorectal cancer were prospectively investigated by using CLE. During extubation, fluorescein 10% was used in conjunction with acriflavine hydrochloride 0.05% to characterize global tissue architecture as well as cytonuclear features of colorectal epithelium. Ex vivo histology was used as gold standard. Reproducibility tests were performed. Results In total, 116 colorectal polyps from 72 patients were examined. Ex vivo histology showed 68 adenomas, 6 invasive carcinomas, 30 hyperplastic polyps, and 12 inflammatory polyps. C-CLE of adenomas revealed lack of epithelial surface maturation, crypt budding, altered vascular pattern, and loss of cell polarity. In contrast, C-CLE of nonadenomatous polyps revealed epithelial surface maturation, and minor abnormalities of crypt architecture and of vascular pattern, and maintained cell polarity. Adenoma dysplasia score reliably discriminated high-grade dysplasia from low-grade dysplasia (accuracy, 96.7%). Interobserver agreement was high (K coefficients: pathologist, 0.92; endomicroscopist, 0.88). In vivo histology predicted ex vivo data with sensitivity of 97.3%, specificity of 92.8%, and accuracy of 95.7%. Conclusions C-CLE accurately discriminates adenomatous from nonadenomatous colorectal polyps and enables evaluation of degree of dysplasia during ongoing endoscopy. This technology might offer considerable potential to ultimately fine-tune surveillance programs, particularly in high-risk groups.

Several studies have shown that counselees do not experience psychopathological levels of distress after DNA test result disclosure. However, it has not systematically been studied whether the absence of psychopathology also means that counselees do not want to receive help. Their self-reported request for help may be related not only with psychopathology/distress but also with other psychological needs (e.g., surgery decisions), genetics-specific needs (e.g., feeling vulnerable/stigmatized), and existential concerns (e.g., meaning in life).Questionnaires were filled in by Dutch cancer patients, before and after disclosure of BRCA1/2 test results for hereditary breast/ovarian cancer: pathogenic mutation results (n = 30), uninformative results (n = 202), or unclassified variants (n = 16). Newly developed questions measured request for help, psychopathology was estimated with factor analyses on distress/psychopathology instruments, and several validated questionnaires measured other needs/concerns.One-third of all counselees who reported a request for psychological help had actually received help. The level of psychopathology correlated between 0.34 and 0.44 with this self-reported need-for-help. Other needs, genetics-specific distress, and existential concerns correlated strongly/moderately with the counselees' self-reported need-for-help. Examples of other needs were intention to undergo surgery, inaccuracy of their interpretation, the impact of cancer, and family communication difficulties. Genetics-specific distress was for instance feeling vulnerable to develop cancer, stigma, and lack of mastery. Existential concerns were, among others, lack of purpose in life, low self-acceptance, and an unfulfilled wish for certainty.The request for help is related to multiple factors. Referral to psychosocial professionals may be improved by not only discussing psychopathology during genetic-counseling sessions but also by other needs and existential concerns. Questions about other needs and existential issues may be added to psychological screening instruments.

Contains fulltext : 89059.pdf (Publisher’s version ) (Closed access) BACKGROUND Li-Fraumeni syndrome (LFS) is a rare autosomal dominant cancer predisposition syndrome. Most families fulfilling the classical diagnostic criteria harbour TP53 germline mutations. However, TP53 germline mutations may also occur in less obvious phenotypes. As a result, different criteria are in use to decide which patients qualify for TP53 mutation analysis, including the LFS, Li-Fraumeni-like (LFL) and Chompret criteria. We investigated which criteria for TP53 mutation analysis resulted in the highest mutation detection rate and sensitivity in Dutch families. We describe the tumour spectrum in TP53-positive families and calculated tumour type specific relative risks. METHOD A total of 180 Dutch families referred for TP53 mutation analysis were evaluated. Tumour phenotypes were verified by pathology reports or clinical records. RESULTS A TP53 germline mutation was identified in 24 families. When the Chompret criteria were used 22/24 mutations were detected (sensitivity 92%, mutation detection rate 21%). In LFS and LFL families 18/24 mutations were found (sensitivity 75%). The two mutations detected outside the 'Chompret group' were found in a child with rhabdomyosarcoma and a young woman with breast cancer. In the mutation carriers, in addition to the classical LFS tumour types, colon and pancreatic cancer were also found significantly more often than in the general population. CONCLUSION We suggest TP53 mutation testing for all families fulfilling the Chompret criteria. In addition, TP53 mutation testing can be considered in the event of childhood sarcoma and breast cancer before 30 years. In addition to the risk for established LFS tumour types, TP53-positive individuals may also have an elevated risk for pancreatic and colon cancer. 01 juni 2010

Contains fulltext : 80314.pdf (Publisher’s version ) (Closed access) The use of pre-implantation genetic diagnosis (PGD) for hereditary cancer is subject to on-going debate, particularly among professionals. This study evaluates the attitude towards PGD and attitude-associated characteristics of those concerned: family members with a hereditary cancer predisposition. Forty-eight Von Hippel-Lindau and 18 Li-Fraumeni Syndrome families were identified via the 9 family cancer clinics in the Netherlands. In total, 216 high risk family members and partners were approached, of whom 179 (83%) completed a self-report questionnaire. Of the high risk family members, 35% expressed a positive attitude towards PGD. Those with a current desire to have children were significantly more likely to have a positive attitude: 48% would consider the use of PGD. No other sociodemographic, medical or psychosocial variables were associated significantly with a positive attitude. The most frequently reported advantage of PGD is the avoidance of a possible pregnancy termination. Uncertainty about late effects was the most frequently reported disadvantage. These results indicate that approximately half of those contemplating a future pregnancy would consider the use of PGD. The actual uptake, however, is expected to be lower. There is no indication that psychosocial factors affect interest in PGD.

A rapid and easy method to screen for aberrant cDNA would be a very useful diagnostic tool in genetics since a fraction of the DNA variants found affect RNA splicing. The currently used RT-PCR methods require new primer combinations to study each variant that might affect splicing. Since MLPA is routinely used to detect large genomic deletions and successfully detected exon skipping events in Duchenne muscular dystrophy in cDNA, we performed a pilot study to evaluate its value for BRCA1 cDNA. The effect of puromycin, DNase I and two different DNA cleaning protocols were tested in the RNA analysis of lymphocyte cultures. We used two samples from unrelated families with two different BRCA1 exon deletion events, two healthy unrelated controls and six samples from hereditary breast/ovarian cancer syndrome (HBOC) patients without BRCA1/2 mutations. Using RNA treated with DNase I and cleaned in a column system from puromycin-treated fractions, we were able to identify the two BRCA1 deletions. Additional HBOC patients did not show additional splice events. However, we were not able to get reproducible results. Therefore, the cDNA-MLPA technique using kit BRCA1 P002 is in our hands currently not reliable enough for routine RNA analysis and needs further optimization.