Paediatric polyposis syndromes: burden of disease and current concepts.

PURPOSE OF REVIEW: Polyposis syndromes are rare but significant entities that often present during childhood and adolescence. Polyposis syndromes should remain high on the differential diagnoses for any child presenting with rectal bleeding, protein-losing enteropathy or intussusception in the setting of multiple polyps in the gastrointestinal tract. There are three primary paediatric polyposis syndromes: Juvenile polyposis syndrome (JPS), Familial adenomatous polyposis (FAP) and Peutz-Jeghers syndrome (PJS). This review will cover recent guidelines for these conditions and advances in genetic testing. RECENT FINDINGS: The first set of paediatric guidelines were released in 2019 by the European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) for FAP, JPS and PJS. Even with advances in genetic testing, a significant proportion of patients with polyposis syndromes have no identifiable genetic mutations. Recent research has shown that polyps behave differently in patients with and without disease-causing variants, emphasizing the role of genetic testing in the diagnosis and management of polyposis syndromes. SUMMARY: Polyposis syndromes in the paediatric population are growing due to increased recognition and advances in genetic testing. A timely diagnosis and surveillance of a paediatric polyposis syndrome are pivotal for the management of disease burden and early identification of cancers within the gastrointestinal tract and beyond. Paediatricians, paediatric gastroenterologists, paediatric oncologists and paediatric surgeons should be familiar with the presentation and comorbidities of polyposis syndromes in children and adolescents. Further research into genotype-phenotype correlations is needed to tailor the care for paediatric patients with polyposis syndromes.

Guidelines for the management of hereditary colorectal cancer from the British Society of Gastroenterology (BSG)/Association of Coloproctology of Great Britain and Ireland (ACPGBI)/United Kingdom Cancer Genetics Group (UKCGG).

Heritable factors account for approximately 35% of colorectal cancer (CRC) risk, and almost 30% of the population in the UK have a family history of CRC. The quantification of an individual's lifetime risk of gastrointestinal cancer may incorporate clinical and molecular data, and depends on accurate phenotypic assessment and genetic diagnosis. In turn this may facilitate targeted risk-reducing interventions, including endoscopic surveillance, preventative surgery and chemoprophylaxis, which provide opportunities for cancer prevention. This guideline is an update from the 2010 British Society of Gastroenterology/Association of Coloproctology of Great Britain and Ireland (BSG/ACPGBI) guidelines for colorectal screening and surveillance in moderate and high-risk groups; however, this guideline is concerned specifically with people who have increased lifetime risk of CRC due to hereditary factors, including those with Lynch syndrome, polyposis or a family history of CRC. On this occasion we invited the UK Cancer Genetics Group (UKCGG), a subgroup within the British Society of Genetic Medicine (BSGM), as a partner to BSG and ACPGBI in the multidisciplinary guideline development process. We also invited external review through the Delphi process by members of the public as well as the steering committees of the European Hereditary Tumour Group (EHTG) and the European Society of Gastrointestinal Endoscopy (ESGE). A systematic review of 10 189 publications was undertaken to develop 67 evidence and expert opinion-based recommendations for the management of hereditary CRC risk. Ten research recommendations are also prioritised to inform clinical management of people at hereditary CRC risk.

Hereditary breast cancer: an update on risk assessment and genetic testing in 2015.

The last 5 years have brought significant innovation and advancement in the genetics of breast cancer. This clinical opinion aims to summarize and update current approaches to the care of women at risk for a hereditary predisposition to breast cancer. Implications of the BRCA mutation and several other hereditary syndromes will be discussed. Risk assessment and criteria for referral to cancer genetic professionals as well as high-risk screening and prophylactic options will be reviewed. Finally, the newly available genetic cancer panels and implications of mutations in some of these lesser known genes will be discussed. As the field of cancer genetics continues to evolve, the education of medical students, residents, and faculty will be paramount to identify appropriate candidates for genetic counseling and testing in conjunction with cancer genetic professionals.

High Resolution Melting analysis as a rapid and efficient method of screening for small mutations in the STK11 gene in patients with Peutz-Jeghers syndrome.

BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare hereditary syndrome characterized by the occurrence of hamartomatous polyps in the gastrointestinal tract, mucocutaneous pigmentation and increased risk of cancer in multiple internal organs. Depending on the studied population, its incidence has been estimated to range from 1:200 000 even up to 1:50 000 births. Being an autosomal disease, PJS is caused in most cases by mutations in the STK11 gene. METHODS: The majority of causative DNA changes identified in patients with PJS are small mutations and, therefore, developing a method of their detection is a key aspect in the advancement of genetic diagnostics of PJS patients. We designed 13 pairs of primers, which amplify at the same temperature and enable examination of all coding exons of the STK11 gene by the HRM analysis. RESULTS: In our group of 41 families with PJS small mutations of the STK11 gene were detected in 22 families (54%). In the remaining cases all of the coding exons were sequenced. However, this has not allowed to detect any additional mutations. CONCLUSIONS: The developed methodology is a rapid and cost-effective screening tool for small mutations in PJS patients and makes it possible to detect all the STK11 gene sequence changes occurring in this group.

Psychosocial impact of Peutz-Jeghers Syndrome.

Peutz-Jeghers Syndrome (PJS) is an autosomal dominant inherited cancer predisposition syndrome and gastrointestinal hamartomatous polyposis syndrome characterized by the presence of distinct perioral freckling. To date, we have not found any tool that specifically assesses the psychosocial impact of PJS on patients. We developed a PJS quality of life questionnaire using expert opinions of 3 cancer genetic counselors and a survey of patients with PJS through recruitment of participants involved in a support group over the internet. We measured and compared our questionnaire results to the widely used Center for Epidemiologic Studies and Depression Scale (CES-D) and the Short Form 36 (SF-36). We recruited 38 patients for our study. Volunteers were mailed a consent form, the self-administered CES-D, SF-36 and our developed PJS questionnaire and were instructed to return the completed questionnaires by mail. Results showed that PJS patients suffer from mild depression even though physically they did not feel impacted by their condition compared to the general population. However, having PJS caused them to alter many important life decisions. The PJS Questionnaire correlated with data obtained from analysis of CES-D, as well as the SF-36. More uniquely, it provided specific information regarding the burden of disease and quality of life in patients affected with Peutz-Jeghers syndrome. Its ability to do so for other polyposis syndrome populations remains to be studied. These results are important in developing plan of care for these patients regarding genetic counseling and surveillance strategies for PJS patients.

Hereditary colorectal cancer syndromes: molecular genetics, genetic counseling, diagnosis and management.

Hereditary forms of colorectal cancer, as is the case with virtually all forms of hereditary cancer, show extensive phenotypic and genotypic heterogeneity, a phenomenon discussed throughout this special issue of Familial Cancer. Clearly, the family physician, oncology specialist, genetic counselor, and cancer geneticist must know fully the complexity of hereditary cancer syndromes, their differential diagnosis, in order to establish a diagnosis, direct highly-targeted surveillance and management, and then be able to communicate effectively with the molecular geneticist so that an at-risk patient's DNA can be tested in accord with the syndrome of concern. Thus, a family with features of the Lynch syndrome will merit microsatellite instability testing, consideration for immunohistochemistry evaluation, and mismatch repair gene testing, while, in contrast, a patient with FAP will require APC testing. However, other germline mutations, yet to be identified, may be important should testing for these mutations prove to be absent and, therein, unrewarding to the patient. Nevertheless, our position is that if the patient's family history is consistent with one of these syndromes, but a mutation is not found in the family, we still recommend the same surveillance and management strategies for patients from families with an established cancer-causing germline mutation. Our purpose in this paper is to provide a concise coverage of the major hereditary colorectal cancer syndromes, to discuss genetic counseling, molecular genetic evaluation, highly targeted surveillance and management, so that cancer control can be maximized for these high hereditary cancer risk patients.

Peutz-Jeghers syndrome and screening for pancreatic cancer.

BACKGROUND: Cancer risk, including pancreatic, is high in those with Peutz-Jeghers syndrome (PJS). It has been suggested that such patients should undergo screening for pancreatic cancer. METHODS: The risk of pancreatic cancer in PJS, pancreatic screening and potential screening strategies were reviewed. Cost-effectiveness was assessed according to American Gastroenterology Association guidelines and a risk stratification model proposed by the European Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer. RESULTS: The risk of pancreatic cancer is increased in PJS but screening would cost over US 35,000 dollars per life saved. Risk stratification reduces cost by 100,000 dollars and costs fall to 50,000 dollars per life saved if deaths from other forms of cancer are avoided. CONCLUSION: Screening should be performed only on a research basis to evaluate the benefit and cost-effectiveness in high-risk groups.

[Current concepts in the genetics of hereditary and sporadic colorectal cancer and the role of genetics in clinical practice: sporadic and IBD-associated colorectal tumors, significance of genetic tests in diagnosis, prognosis and assessment of chemotherapy outcome]. / A hereditaer és sporadikus colorectalis daganatok genetikája és a genetikai ismeretek jelentosége a mindennapi gyakorlatban: sporadikus és IBD-asszociált colorectalis tumorok, illetve a genetikai vizsgálatok jelentosége a diagnózisban, prognózisban és a kemoterápiára adott válasz megítélésében.

There has been a major improvement in our understanding in the area of the genetics of CRC in the last decade. Reason for this is partly that CRC has a strong hereditary trait and premalignant lesions are frequent and easily accessible. In the 1990-ies the mutations responsible for the adenoma-carcinoma sequence were discovered on after the other. In the second part of the review the authors discuss the genetic background of sporadic and IBD associated colorectal cancers as well as the role of genetics in the diagnosis, prognosis and prediction of therapy. Chromosomal instability (85%) and microsatellite instability with or without change in DNA methylation (15%) are the main mechanisms involved in the pathogenesis of sporadic colorectal cancers. It became evident that no ultimate mutations exist. Most of neoplasms are genetically heterogeneous, independent pathways and simultaneous tumorigenesis may exist within the same organ, also in the colon. Gene expression profile, clinical phenotype and prognosis may also vary according to the location. Similar genetic mutations may be found in IBD associated colorectal cancers, however, the typical sequence and importance of mutations is different. In future, fecal DNA testing may be an important screening tool for colorectal cancer; however, its routine use is still limited by its low sensitivity. Similarly, genetic investigation may play an increasing role in the prediction of prognosis, therapy and complication of chemotherapy. A more distant goal may be the individualization of the therapy.

Breast and ovarian cancer genetics and prevention.

Inherited breast and ovarian cancers account for 10% of all breast and ovarian cancers. Relative to sporadic breast and ovarian cancers, these cancers tend to occur at an earlier age and grow more aggressively. Women with BRCA1 and BRCA2 mutations (BRCA1/2 mutation) have a 65% to 85% cumulative lifetime risk of developing invasive breast cancer and a 15% to 65% cumulative lifetime risk of developing invasive ovarian cancer. Identification of patients with the mutation is therefore crucial, because preventive measures such as prophylactic bilateral mastectomy, prophylactic bilateral salpingpo-oophorectomy and chemoprevention with Tamoxifen can prevent breast and ovarian cancer. Likewise, genetic counseling prior to testing is important, considering the major impact of the test results on an individual's life.

Genetic testing for cancer predisposition.

Clinical cancer genetics is becoming an integral part of the care of cancer patients. This review describes the clinical aspects, genetics, and clinical genetic management of most of the major hereditary cancer susceptibility syndromes. Multiple endocrine neoplasia type 2, von Hippel-Lindau disease, and familial adenomatous polyposis are examples of syndromes for which genetic testing to identify at-risk family members is considered the standard of care. Genetic testing for these syndromes is sensitive and affordable, and it will change medical management. Cancer genetic counseling and testing is probably beneficial in other syndromes, such as the hereditary breast cancer syndromes, hereditary nonpolyposis colorectal cancer syndrome, Peutz-Jeghers syndrome, and juvenile polyposis. There are also hereditary cancer syndromes for which testing is not yet available and/or is unlikely to change medical management, including Li-Fraumeni syndrome and hereditary malignant melanoma. Thorough medical care requires the identification of families likely to have a hereditary cancer susceptibility syndrome for referral to cancer genetics professionals.