Hereditary Cancer in Clinical Practice最新文献

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.

BRCA1 and BRCA2 mutations contribute to both breast cancer and ovarian cancer worldwide. In Poland approximately 4% of patients with breast cancers and 10% of patients with ovarian cancer carry a mutation in BRCA1. The majority of mutations consist of three founder mutations. A rapid inexpensive test for these three mutations can be used to screen all Polish adults at a reasonable cost. In the region of Pomerania of North-western Poland nearly half a million tests have been performed, in large part through engaging family doctors and providing ready access to testing through the Pomeranian Medical University. The following commentary provides a history of genetic testing for cancer in Pomerania and the current approach to facilitating access to genetic testing at the Cancer Family Clinic for all adults living in the region.

Background: Lynch syndrome (LS) is not considered part of childhood cancer predisposition syndromes.

Case presentation: Analysis of a pediatric osteosarcoma (OS) displayed hypermutation (16.8), alternative lengthening of telomeres (ALT), loss of PMS2 expression in tumor tissue (retained in non-neoplastic cells), PMS2 loss of heterozygosity (LOH), and high-degree of microsatellite instability (MSI) tested by PCR. A heterozygous duplication c.1076dup p.(Leu359Phefs*6) in exon 10 of NM_000535.6:PMS2 was detected by SNV analysis in peripheral blood, confirming diagnosis of LS in the patient. The tumor molecular features suggest LS-associated development of OS. In a second case, whole-genome sequencing identified a heterozygous SNV c.1 A > T p.? in exon 1 of PMS2 in tumor and germline material of a girl with ependymoma. Tumor analysis displayed evidence for ALT and low mutational burden (0.6), PMS2 expression was retained, MSI was low. Multiplex ligation-dependent probe amplification identified no additional PMS2 variant and germline MSI testing did not reveal increased gMSI ratios in the patient´s lymphocytes. Thus, CMMRD was most closely excluded and our data do not suggest that ependymoma was related to LS in the child.

Conclusions: Our data suggest that the LS cancer spectrum may include childhood cancer. The importance of LS in pediatric cancers necessitates prospective data collection. Comprehensive molecular workup of tumor samples is necessary to explore the causal role of germline genetic variants.

The end of each chromosome consists of a DNA region termed the telomeres. The telomeres serve as a protective shield against degradation of the coding DNA sequence, as the DNA strand inevitably ‒ with each cell division ‒ is shortened. Inherited genetic variants cause telomere biology disorders when located in genes (e.g. DKC1, RTEL1, TERC, TERT) playing a role in the function and maintenance of the telomeres. Subsequently patients with telomere biology disorders associated with both too short or too long telomeres have been recognized. Patients with telomere biology disorders associated with short telomeres are at increased risk of dyskeratosis congenita (nail dystrophy, oral leukoplakia, and hyper- or hypo-pigmentation of the skin), pulmonary fibrosis, hematologic disease (ranging from cytopenia to leukemia) and in rare cases very severe multiorgan manifestations and early death. Patients with telomere biology disorders associated with too long telomeres have in recent years been found to confer an increased risk of melanoma and chronic lymphocytic leukemia. Despite this, many patients have an apparently isolated manifestation rendering telomere biology disorders most likely underdiagnosed. The complexity of telomere biology disorders and many causative genes makes it difficult to design a surveillance program which will ensure identification of early onset disease manifestation without overtreatment.

Background: The study purpose is to compare outcomes associated with completion of genetic testing between telemedicine and in-person gastrointestinal cancer risk assessment appointments during the COVID-19 pandemic.

Methods: Data was collected on patients with scheduled appointments between July 2020 and June 2021 in a gastrointestinal cancer risk evaluation program (GI-CREP) that utilized both telemedicine and in-person visits throughout the COVID-19 pandemic, and a survey was administered.

Results: A total of 293 patients had a GI-CREP appointment scheduled and completion rates of in-person versus telemedicine appointments were similar. Individuals diagnosed with cancer and those with Medicaid insurance had lower rates of appointment completion. Although telehealth was the preferred visit modality, there were no differences in recommending genetic testing nor in the consent rate for genetic testing between in-person and telemedicine visits. However, of patients who consented for genetic testing, more than three times more patients seen via telemedicine did not complete genetic testing compared to those seen in-person (18.3% versus 5.2%, p = 0.008). Furthermore, telemedicine visits had a longer turnaround time for genetic test reporting (32 days versus 13 days, p < 0.001).

Conclusions: Compared to in-person GI-CREP appointments, telemedicine was associated with lower rates of genetic testing completion, and longer turnaround time for results.

Background: Although Singapore is one of the highest vaccinated countries in the world, vaccine hesitancy remains in a subpopulation, including individuals with cancer predisposition syndromes. At the Cancer Genetics Service National Cancer Centre Singapore, we see patients with germline genetic alterations, most being BRCA1/2 pathogenic/likely pathogenic variant (PV/LPV) carriers. While reported safe for cancer patients, there are limited studies addressing the safety profile and outcomes of COVID-19 vaccination among individuals with germline PV/LPV in cancer predisposition genes such as BRCA1/2. This study aims to evaluate the outcomes of COVID-19 vaccination among germline PV/LPV carriers in BRCA1/2.

Methods: We conducted a phone call survey of COVID-19 vaccination uptake and toxicity in a prospective cohort of 189 participants with germline BRCA1/2 PV/LPV between 1st Sept 2021 and 30th Sept 2021. We collected demographics data including gender, race, age, history of cancer, types of cancer, and number of cancers. Statistical difference in baseline demographics between responders with history of cancer and those without were assessed using Chi-square, Fisher's exact and independent t-test analysis. Logistic regression was used to evaluate effect of demographics on the occurrence of post-vaccination side effects.

Results: Among 189 BRCA1/2 PV/LPV carriers responded, 97 carried PV/LPV in BRCA1 and 92 in BRCA2. Majority were vaccinated (89.5%) and had completed the two-dose vaccine schedule, with 7 (4.1%) received only one dose. The most common post-vaccination side effects was myalgia (56.5%) followed by fever (40.2%), headache (16.3%) and fatigue (11.2%). There were no major severe side events. Evaluation by logistic regression showed that the occurrence of side effects was not affected by PV/LPV gene (BRCA1 or BRCA2), gender, race, age or history of cancer.

Conclusion: The post-vaccination side effects profile among individuals with germline PV/LPV in BRCA1/2 is consistent with the Singaporean general population, hence recommendations for COVID-19 vaccination for these individuals should not differ from non-carriers and should be encouraged by their healthcare providers.