Hereditary Cancer in Clinical Practice最新文献

The recognition of dominantly inherited micro-satellite instable (MSI) cancers caused by pathogenic variants in one of the four mismatch repair (MMR) genes MSH2, MLH1, MSH6 and PMS2 has modified our understanding of carcinogenesis. Inherited loss of function variants in each of these MMR genes cause four dominantly inherited cancer syndromes with different penetrance and expressivities: the four Lynch syndromes. No person has an "average sex "or a pathogenic variant in an "average Lynch syndrome gene" and results that are not stratified by gene and sex will be valid for no one. Carcinogenesis may be a linear process from increased cellular division to localized cancer to metastasis. In addition, in the Lynch syndromes (LS) we now recognize a dynamic balance between two stochastic processes: MSI producing abnormal cells, and the host's adaptive immune system's ability to remove them. The latter may explain why colonoscopy surveillance does not reduce the incidence of colorectal cancer in LS, while it may improve the prognosis. Most early onset colon, endometrial and ovarian cancers in LS are now cured and most cancer related deaths are after subsequent cancers in other organs. Aspirin reduces the incidence of colorectal and other cancers in LS. Immunotherapy increases the host immune system's capability to destroy MSI cancers. Colonoscopy surveillance, aspirin prevention and immunotherapy represent major steps forward in personalized precision medicine to prevent and cure inherited MSI cancer.

Introduction: We present a case of a male patient with neurofibromatosis type 1 diagnosed with pancreatic divisum and several gastrointestinal tumors. A 55-year-old man was admitted to the hospital with recurrent chronic pancreatitis, indicating a large mass in the ampulla. In addition, genetic testing revealed two unique germline mutations in the neurofibromin (NF1) gene, and their potential interaction in promoting cancer was further investigated.

Conclusion: The first similar case was reported in 2020. The current case was distinct from other cases since an additional two NF1 mutations were found in the patient. In conjunction with prior case reports, our findings imply that genetic testing in patients diagnosed with neurofibromatosis type 1 could be helpful in the development of effective treatments.

Background: Familial pancreatic cancer touches families through a genetic susceptibility to developing this neoplasia. Genetic susceptibility is assessed via family history, genetic testing, or both. Individuals with two or more first-degree relatives or three or more relatives of any degree diagnosed with pancreatic cancer are considered at elevated risk. Following a diagnosis of familial pancreatic cancer, patients and families face uncertainty and anxiety about the future. Psychosocial effects of a pancreatic cancer diagnosis on families include fear, concerns about personal health, and how lifestyle may impact the risk of developing pancreatic cancer.

Case presentation: A 66-year-old male was diagnosed with pancreatic ductal adenocarcinoma stage IIB, T3, N1, M0. A genetic referral was made due to a history of multiple cases of pancreatic cancer within the patient's family. Genetic testing revealed the patient had a pathogenic variant in the ATM gene that is associated with an increased risk for pancreatic cancer development. The patient's one adult child was offered testing due to the autosomal dominant pattern of inheritance for this variant. The adult child was found to have the same pathogenic variant. She expressed fear for her future and her child's future health and longevity. Discussing a case study allows us to capture the multi-faceted relationship between the disease, the affected individuals, and their families. Examining the psychosocial stresses and concerns when there is a pancreatic cancer diagnosis in the family is essential to provide holistic care to patients and families.

Conclusions: The psychosocial effects of FPC may be overwhelming for patients and families. Healthcare providers can offer education, support, and referrals to appropriate services to help families cope through stages of evaluation, diagnosis, and treatment of FPC.

Background: WNT signaling is pivotal in embryogenesis and tissue homeostasis. Aberrant WNT signaling, due to mutations in components of this pathway, contributes to the development and progression of human cancers, including colorectal cancer. AXIN2, encoded by the AXIN2 gene, is a key negative regulator and target of the canonical WNT signaling pathway. Germline mutations in AXIN2 are associated with absence of permanent teeth (hypo- and oligodontia) and predisposition to gastrointestinal polyps and cancer. The limited number of patients makes an accurate genotype-phenotype analysis currently challenging.

Case presentation: We present the case of a 55-year-old male with colorectal polyposis and hypodontia. Genetic testing confirmed a novel frameshift germline mutation in exon 8 of the AXIN2 gene. In addition, we provide an updated overview of germline AXIN2 mutations reported in literature.

Conclusions: Although the number of missing teeth is less severe in our patient than in some previously reported cases, our findings provide additional evidence that missing teeth and gastrointestinal neoplasia are associated with rare pathogenic AXIN2 germline mutations.

Background: High-risk surveillance for patients with Li-Fraumeni syndrome (LFS) has shown a stage shift and improved overall survival, but is demanding. Our objective was to evaluate surveillance adherence in a population of patients with LFS presenting for high-risk care.

Methods: A retrospective analysis of surveillance adherence of adult patients with LFS at a single institution was performed. Adherence was defined by the duration from initial University of Virginia (UVA) LFS clinic visit to the time of first missed surveillance test. Two-sample t-tests and ANOVA tests were used to identify factors associated with duration of adherence.

Results: A total of 42 patients were evaluated in the UVA LFS clinic between 2017 and 2021. Of these, 21 patients met inclusion criteria. At the time of review, 6 patients (29%) were up to date with high-risk surveillance recommendations. The mean duration of adherence was 17 months. Female sex was found to be associated with longer duration of adherence (mean 21 mo vs. 3.5 mo for males, p = 0.02). A personal history or active diagnosis of cancer was also associated with increased adherence (p = 0.02). However, neither age (p = 0.89), geography (p = 0.84), or known family history of LFS (p = 0.08) were associated with duration of adherence.

Conclusion: Female sex as well as a personal history of cancer were associated with longer duration of adherence to recommended high-risk surveillance among patients with LFS. Identification of barriers to surveillance will be essential moving forward to increase adherence and promote early detection of cancer, thereby reducing the morbidity and mortality of LFS.

Backgrounds: This study aimed to evaluate the changes in the rates of genetic counseling and genetic testing as well as the diagnosis rate of Lynch syndrome (LS)-associated colorectal cancer before and after multistep approach with multidisciplinary team in Japanese.

Methods: In September 2016, we started universal screening for LS by mismatch repair protein immunohistochemistry and prospectively collected the records. Following patient interviews, we started multistep approach with multidisciplinary team (MA) in January 2020. MA consists of six surgeons, one genetic counselor, one medical geneticist, and six pathologists. MA is set up to compensate for patients' lack of knowledge about genetic diseases and make case selection for elderly colorectal cancer patients with deficient mismatch repair (dMMR). MA is designed as a system that could be performed by a small number of medical genetic specialists. A total of 522 patients were included during the study duration, 323 and 199 patients in the pre-MA (P-MA) and MA groups, respectively.

Results: The frequency of dMMR in all patients was 10.0%. The patient interview results indicated a significant lack of patient education regarding genetic diseases. The rates of genetic counseling and genetic testing was significantly higher in MA group than in P-MA group (genetic counseling: MA 34.6% vs. P-MA 7.7%, p = 0.04; genetic testing: MA 30.8% vs. P-MA 3.8%, p = 0.02). Moreover, the diagnosis rate of LS-associated colorectal cancer was significantly higher in MA group (2.5%) than in P-MA group (0.3%) (P = 0.03). In addition, MA could be performed without problems despite the small number of medical and human genetics specialists.

Conclusions: MA has achieved appropriate pickup of suspected hereditary colorectal cancer patients and complemented the lack of knowledge about genetic diseases. The introduction of MA increased LS-associated colorectal cancer after universal screening. MA is an appropriate LS screening protocol for Japanese patients who lag behind in medical and human genetics education.

Background: Synchronous endometrial and ovarian cancer (SEOC) accounts for 50-70% of all synchronous gynecology cancers in women. Approximately 14% of SEOC cases are caused by Lynch syndrome (LS). The widespread introduction of "universal screening" at LS (all cases with CRC and all EC cases diagnosed before age 60 should be tested for MMR deficiency) has led to an increasing number of suspected LS cases- MMR-deficient tumors without germline mutation in the MMR genes. These cases are attributed to the so-called Lynch-like syndrome (LLS).

Case presentation: We present a case of LLS with a detected germline, likely pathogenic variant in the WRN gene. The proband was a woman diagnosed with SEOC at the age of 51 years. Histology of both tumors (endometrium and ovary) was endometroid and showed loss of MLH1 and PMS protein expression. Genetic testing by next generation sequencing (NGS) detected a germline mutation (in the heterozygous state) in the WRN gene - c.4109del, p.(Asn1370ThrfsTer23) in the proband.

Conclusions: The presented case contributes to the etiology of LLS and confirms the need for specific genetic testing, together with genetic counseling, in hereditary cancer syndromes. The use of combined information from clinicians, pathologists, genetic counselors, and data from NGS testing for cancer predisposition, clinical surveillance, and follow-up management in women with gynecology cancers, especially SEOC, could be improved.

Background: Juvenile Polyposis Syndrome (JPS) is an autosomal dominant condition with hamartomatous polyps in the gastrointestinal tract, associated with an increased risk of gastrointestinal malignancy. Disease causing variants (DCVs) in BMPR1a or SMAD4 account for 45-60% of JPS cases, with BMPR1a DCVs accounting for 17-38% of JPS cases. Within those with either a BMPR1a or SMAD4 DCV, there is phenotypic variability in location of polyps, risk of malignancy and extra-intestinal manifestations with limited published reports of gene-phenotype association or genotype-phenotype correlation. We aimed to identify any gene-phenotype association or genotype-phenotype correlation in BMPR1a to inform surveillance recommendations, and gene-specific modification to the ACMG classification of pathogenicity of DCVs.

Methods: A literature search was performed through EMBASE, MEDLINE and PubMed. Studies that were included explored BMPR1a DCV-related JPS or contiguous deletion of PTEN and BMPR1a. Data was also drawn from the BMPR1a specific databases on LOVD and ClinVar.

Results: There were 211 DCVs in BMPR1a identified, 82 from patients with JPS in the literature, and 17 from LOVD and 112 from ClinVar classified as pathogenic or likely pathogenic. These included missense, nonsense and frameshift variants and large deletions, occurring across all functional domains of the gene. Unlike in SMAD4 carriers, gastric polyposis and malignancy were not identified in our review in BMPR1a carriers, but colonic polyposis and malignancy occurred in carriers of either BMPR1a or SMAD4 DCVs. Those with contiguous deletion of PTEN and BMPR1a can present with JPS of infancy, with a severe phenotype of GI bleeding, diarrhoea, exudative enteropathy and rectal prolapse. No specific BMPR1a genotype-phenotype correlation could be ascertained including by variant type or functional domain.

Conclusion: Phenotypic characteristics cannot be used to inform variant location in BMPR1a. However, the phenotypic characteristics of BMPR1a DCV carriers, being almost exclusively related to the colon and rectum, can assist in pathogenicity assessment of BMPR1a variants. Given these findings, we propose that carriers of BMPR1a DCVs should only require surveillance for colorectal polyps and malignancy, and that surveillance for gastric polyps and malignancy may be unnecessary. However variant location within BMPR1a does not support differential surveillance recommendations.

A founder variant is a genetic alteration, that is inherited from a common ancestor together with a surrounding chromosomal segment, and is observed at a high frequency in a defined population. This founder effect occurs as a consequence of long-standing inbreeding of isolated populations. For high-risk cancer predisposition genes, such as BRCA1/2, the identification of founder variants in a certain population could help designing customized cost-effective cancer screening panels. This advantage has been best utilized in designing a customized breast cancer BRCA screening panel for the Ashkenazi Jews (AJ) population, composed of the three BRCA founder variants which account for approximately 90% of identified BRCA alterations. Indeed, the high prevalence of pathogenic BRCA1/2 variants among AJ (~ 2%) has additionally contributed to make population-based screening cost-effective in comparison to family-history-based screening. In Jordan there are multiple demographic characteristics supporting the proposal of a founder effect. A high consanguinity rate of ~ 57% in the nineties of the last century and ~ 30% more recently is a prominent factor, in addition to inbreeding which is often practiced by different sub-populations of the country.This review explains the concept of founder effect, then applies it to analyze published Jordanian BRCA variants, and concludes that nine pathogenic (P) and likely pathogenic (LP) BRCA2 variants together with one pathogenic BRCA1 variant are potential founder variants. Together they make up 43% and 55% of all identified BRCA1/2 alterations in the two largest studied cohorts of young patients and high-risk patients respectively. These variants were identified based on being recurrent and either specific to ethnic groups or being novel. In addition, the report highlights the required testing methodologies to validate these findings, and proposes a health economic evaluation model to test cost-effectiveness of a population-based customized BRCA screening panel for the Jordanian population. The aim of this report is to highlight the potential utilization of founder variants in establishing customized cancer predisposition services, in order to encourage more population-based genomic studies in Jordan and similar populations.