Irma Kluijt

The yield of first-time endoscopic ultrasonography in screening individuals at a high risk of developing pancreatic cancer

OBJECTIVES:Approximately 10–15% of all pancreatic cancers (PCs) may be hereditary in origin. We investigated the use of endoscopic ultrasonography (EUS) for the screening of individuals at high risk for developing PC. In this paper the results of first-time screening with EUS are presented.METHODS:Those eligible for screening in this study were first-degree family members of affected individuals from familial pancreatic cancer (FPC) families, mutation carriers of PC-prone hereditary syndromes, individuals with Peutz–Jeghers syndrome, and mutation carriers of other PC-prone hereditary syndromes with clustering (≥2 cases per family) of PC. All individuals were asymptomatic and had not undergone EUS before.RESULTS:Forty-four individuals (M/F 18/26), aged 32–75 years underwent screening with EUS. Thirteen were from families with familial atypical multiple-mole melanoma (FAMMM), 21 with FPC, 3 individuals were diagnosed with hereditary pancreatitis, 2 were Peutz–Jeghers patients, 3 were BRCA1 and 2 were BRCA2 mutation carriers with familial clustering of PC, and 1 individual had a p53 mutation. Three (6.8%) patients had an asymptomatic mass lesion (12, 27, and 50 mm) in the body (n=2) or tail of the pancreas. All lesions were completely resected. Pathology showed moderately differentiated adenocarcinomas with N1 disease in the two patients with the largest lesions. EUS showed branch-type intraductal papillary mucinous neoplasia (IPMN) in seven individuals.CONCLUSIONS:Screening of individuals at a high risk for PC with EUS is feasible and safe. The incidence of clinically relevant findings at first screening is high with asymptomatic cancer in 7% and premalignant IPMN-like lesions in 16% in our series. Whether screening improves survival remains to be determined, as does the optimal screening interval with EUS.

TP53 germline mutation testing in 180 families suspected of Li–Fraumeni syndrome: mutation detection rate and relative frequency of cancers in different familial phenotypes

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.

Risks of Less Common Cancers in Proven Mutation Carriers With Lynch Syndrome

PURPOSE Patients with Lynch syndrome are at high risk for colon and endometrial cancer, but also at an elevated risk for other less common cancers. The purpose of this retrospective cohort study was to provide risk estimates for these less common cancers in proven carriers of pathogenic mutations in the mismatch repair (MMR) genes MLH1, MSH2, and MSH6. PATIENTS AND METHODS Data were pooled from the German and Dutch national Lynch syndrome registries. Seven different cancer types were analyzed: stomach, small bowel, urinary bladder, other urothelial, breast, ovarian, and prostate cancer. Age-, sex- and MMR gene-specific cumulative risks (CRs) were calculated using the Kaplan-Meier method. Sex-specific incidence rates were compared with general population incidence rates by calculating standardized incidence ratios (SIRs). Multivariate Cox regression analysis was used to estimate the impact of sex and mutated gene on cancer risk. RESULTS The cohort comprised 2,118 MMR gene mutation carriers (MLH1, n = 806; MSH2, n = 1,004; MSH6, n = 308). All cancers were significantly more frequent than in the general population. The highest risks were found for male small bowel cancer (SIR, 251; 95% CI, 177 to 346; CR at 70 years, 12.0; 95% CI, 5.7 to 18.2). Breast cancer showed an SIR of 1.9 (95% CI, 1.4 to 2.4) and a CR of 14.4 (95% CI, 9.5 to 19.3). MSH2 mutation carriers had a considerably higher risk of developing urothelial cancer than MLH1 or MSH6 carriers. CONCLUSION The sex- and gene-specific differences of less common cancer risks should be taken into account in cancer surveillance and prevention programs for patients with Lynch syndrome.

Genetic Testing in Li-Fraumeni Syndrome: Uptake and Psychosocial Consequences

PURPOSE Li-Fraumeni syndrome (LFS) is a hereditary cancer syndrome, characterized by a high risk of developing cancer at various sites and ages. To date, limited clinical benefits of genetic testing for LFS have been demonstrated, and there are concerns about the potential adverse psychosocial impact of genetic testing for LFS. In this study, we evaluated the uptake of genetic testing and the psychosocial impact of undergoing or not undergoing a genetic test for LFS. PATIENTS AND METHODS In total, 18 families with a p53 germline mutation in the Netherlands were identified. Eligible family members were invited to complete a self-report questionnaire assessing motives for undergoing or not undergoing genetic testing, LFS-related distress and worries, and health-related quality of life. RESULTS Uptake of presymptomatic testing was 55% (65 of 119). Of the total group, 23% reported clinically relevant levels of LFS-related distress. Carriers were not significantly more distressed than noncarriers or than those with a 50% risk who did not undergo genetic testing. Those with a lack of social support were more prone to report clinically relevant levels of distress (odds ratio, 1.3; 95% CI, 1.0 to 1.5). CONCLUSION Although preventive and treatment options for LFS are limited, more than half of the family members from known LFS families choose to undergo presymptomatic testing. An unfavorable genetic test result, in general, does not cause adverse psychological effects. Nonetheless, it is important to note that a substantial proportion of individuals, irrespective of their carrier status, exhibit clinically relevant levels of distress which warrant psychological support.

CDH1-related hereditary diffuse gastric cancer syndrome : Clinical variations and implications for counseling

CDH1 mutation carriers have a strongly increased risk of developing gastric cancer (GC) and lobular breast cancer (LBC). Clinical data of GC cases and surgical and histological data of prophylactic gastrectomies and mastectomies of all 10 Dutch CDH1 mutation families were collected. In vitro functional assays were performed to analyze the nature of the newly found missense mutation c.1748T>G (p.Leu583Arg). Ten different CDH1 mutations were found. Functional assays gave strong arguments for the pathogenic nature of the p.Leu583Arg mutation. The pedigrees comprised 36 GC cases (mean age 40 years, range 20–72 years) and one LBC case. Twenty‐nine/37 carriers alive, aged 18–61 years, underwent prophylactic gastrectomy. Invasive GC‐foci and premalignant abnormalities were detected in 2 and 25 patients, respectively. In four patients GC/signetring cell (SRC) foci were diagnosed at preoperative gastroscopy. Long‐standing presence of SRCs without progression to invasive carcinoma was shown in two others. Multifocal LBC/LCIS was found in the two prophylactic mastectomy specimens. Clefts of lip and/or palate (CL/P) were reported in seven individuals from three families. The age at onset and aggressiveness of GC is highly variable, which has to be included in counseling on planning prophylactic gastrectomies. The incidence of LBC is expected to increase and prophylactic mastectomy needs to be considered. The relationship between CL/P and CDH1 needs further study to inform future parents from hereditary diffuse gastric cancer (HDGC) families adequately.

An α‐E‐catenin (CTNNA1) mutation in hereditary diffuse gastric cancer

Diffuse gastric cancers typically present as late‐stage tumours and, as a result, the 5 year survival rate is poor. Some gastric cancers are hereditary and these tend to be of the diffuse type; 30–40% of hereditary diffuse gastric cancers (HDGCs) can be explained by defective germline alleles of E‐cadherin (CDH1), but for the remaining families the factors driving susceptibility remain unknown. We had access to a large HDGC pedigree with no obvious mutation in CDH1, and applied exome sequencing to identify new genes involved in gastric cancer. We identified a germline truncating allele of α‐E‐catenin (CTNNA1) that was present in two family members with invasive diffuse gastric cancer and four in which intramucosal signet ring cells were detected as part of endoscopic surveillance. The remaining CTNNA1 allele was silenced in the two diffuse gastric cancers from the family that were available for screening, and this was also true for signet ring cells identified in endoscopic biopsies. Since α‐E‐catenin functions in the same complex as E‐cadherin, our results call attention to the broader signalling network surrounding these proteins in HDGC. We also detected somatic mutations in one tumour and found substantial overlap with genes mutated in sporadic gastric cancer, including PIK3CA, ARID1A, MED12 and MED23.

A multicentre comparative prospective blinded analysis of EUS and MRI for screening of pancreatic cancer in high-risk individuals.

Objective Endoscopic ultrasonography (EUS) and MRI are promising tests to detect precursors and early-stage pancreatic ductal adenocarcinoma (PDAC) in high-risk individuals (HRIs). It is unclear which screening technique is to be preferred. We aimed to compare the efficacy of EUS and MRI in their ability to detect clinically relevant lesions in HRI. Design Multicentre prospective study. The results of 139 asymptomatic HRI (>10-fold increased risk) undergoing first-time screening by EUS and MRI are described. Clinically relevant lesions were defined as solid lesions, main duct intraductal papillary mucinous neoplasms and cysts ≥10 mm. Results were compared in a blinded, independent fashion. Results Two solid lesions (mean size 9 mm) and nine cysts ≥10 mm (mean size 17 mm) were detected in nine HRI (6%). Both solid lesions were detected by EUS only and proved to be a stage I PDAC and a multifocal pancreatic intraepithelial neoplasia 2. Of the nine cysts ≥10 mm, six were detected by both imaging techniques and three were detected by MRI only. The agreement between EUS and MRI for the detection of clinically relevant lesions was 55%. Of these clinically relevant lesions detected by both techniques, there was a good agreement for location and size. Conclusions EUS and/or MRI detected clinically relevant pancreatic lesions in 6% of HRI. Both imaging techniques were complementary rather than interchangeable: contrary to EUS, MRI was found to be very sensitive for the detection of cystic lesions of any size; MRI, however, might have some important limitations with regard to the timely detection of solid lesions.

CHEK2*1100delC homozygosity is associated with a high breast cancer risk in women

Background Mutations in the CHEK2 gene confer a moderately increased breast cancer risk. The risk for female carriers of the CHEK2*1100delC mutation is twofold increased. Breast cancer risk for carrier women is higher in a familial breast cancer setting which is due to coinheritance of additional genetic risk factors. This study investigated the occurrence of homozygosity for the CHEK2*1100delC allele among familial breast cancer cases and the associated breast cancer risk. Methods and results Homozygosity for the CHEK2*1100delC allele was identified in 8/2554 Dutch independent familial non-BRCA1/2 breast cancer cases. The genotype relative risk for breast cancer of homozygous and heterozygous familial breast cancer cases was 101.34 (95% CI 4.47 to 121 000) and 4.04 (95% CI 0.88 to 21.0), respectively. Female homozygotes appeared to have a greater than twofold increased breast cancer risk compared to familial CHEK2*1100delC heterozygotes (p=0.044). These results and the occurrence of multiple primary tumours in 7/10 homozygotes indicate a high cancer risk in homozygous women from non-BRCA1/2 families. Conclusions Intensive breast surveillance is therefore justified in these homozygous women. It is concluded that diagnostic testing for biallelic mutations in CHEK2 is indicated in non-BRCA1/2 breast cancer families, especially in populations with a relatively high prevalence of deleterious mutations in CHEK2.

Colorectal Cancer in the Family: Psychosocial Distress and Social Issues in the Years Following Genetic Counselling

BackgroundThis study examined: (1) levels of cancer-specific distress more than one year after genetic counselling for hereditary nonpolyposis colorectal cancer (HNPCC); (2) associations between sociodemographic, clinical and psychosocial factors and levels of distress; (3) the impact of genetic counselling on family relationships, and (4) social consequences of genetic counselling.MethodsIn this cross-sectional study, individuals who had received genetic counselling for HNPCC during 1986–1998 completed a self-report questionnaire by mail.Results116 individuals (81% response rate) completed the questionnaire, on average 4 years after the last counselling session. Of all respondents, 6% had clinically significant levels of cancer-specific distress (Impact of Event Scale, IES). Having had contact with a professional psychosocial worker for cancer risk in the past 10 years was significantly associated with higher levels of current cancer specific distress. Only a minority of the counselees reported any adverse effects of genetic counselling on: communication about genetic counselling with their children (9%), family relationships (5%), obtaining life insurance (8%), choice or change of jobs (2%), and obtaining a mortgage (2%).ConclusionOn average, four years after genetic counselling for HNPCC, only a small minority of counselled individuals reports clinically significant levels of distress, or significant family or social problems.

Familial gastric cancer: guidelines for diagnosis, treatment and periodic surveillance

Hereditary diffuse gastric cancer (HDGC) is a relatively rare disorder, with a mutated CDH1 gene as the only known cause. Carriers of a germline mutation in CDH1 have a lifetime risk of >80% of developing diffuse gastric cancer. As periodic gastric surveillance is of limited value in detecting early stages of HDGC, prophylactic gastrectomy is advised for this patient group. Little is known about other types of familial gastric cancer. The Dutch working group on hereditary gastric cancer has formulated guidelines for various aspects of medical management for families and individuals at high risk of developing gastric cancer, including criteria for referral, classification, diagnostics, and periodic gastric surveillance. These guidelines are not limited to HDGC and are therefore partially complementary to the guidelines on hereditary diffuse gastric cancer of the international gastric cancer linkage consortium (IGCLC 2010). In order to optimize the care and increase the knowledge on hereditary gastric cancer it is important to centralize medical care for these patients. National and international collaboration is warranted to improve the quality of research by increasing the size of study cohorts.