bims-lifras Biomed News
on Li-Fraumeni syndrome
Issue of 2020‒03‒29
ten papers selected by
Joanna Zawacka-Pankau



  1. Blood Adv. 2020 Mar 24. 4(6): 1131-1144
      First reported in 1999, germline runt-related transcription factor 1 (RUNX1) mutations are a well-established cause of familial platelet disorder with predisposition to myeloid malignancy (FPD-MM). We present the clinical phenotypes and genetic mutations detected in 10 novel RUNX1-mutated FPD-MM families. Genomic analyses on these families detected 2 partial gene deletions, 3 novel mutations, and 5 recurrent mutations as the germline RUNX1 alterations leading to FPD-MM. Combining genomic data from the families reported herein with aggregated published data sets resulted in 130 germline RUNX1 families, which allowed us to investigate whether specific germline mutation characteristics (type, location) could explain the large phenotypic heterogeneity between patients with familial platelet disorder and different HMs. Comparing the somatic mutational signatures between the available familial (n = 35) and published sporadic (n = 137) RUNX1-mutated AML patients showed enrichment for somatic mutations affecting the second RUNX1 allele and GATA2. Conversely, we observed a decreased number of somatic mutations affecting NRAS, SRSF2, and DNMT3A and the collective genes associated with CHIP and epigenetic regulation. This is the largest aggregation and analysis of germline RUNX1 mutations performed to date, providing a unique opportunity to examine the factors underlying phenotypic differences and disease progression from FPD to MM.
    DOI:  https://doi.org/10.1182/bloodadvances.2019000901
  2. Am Soc Clin Oncol Educ Book. 2020 Mar;40 1-12
      Secondary sarcomas are a subset of sarcomas that occur in patients with prior cancer diagnoses and are associated with environmental or genetic factors. Although secondary sarcomas are rare in general, there are predisposing factors that can substantially increase this risk in certain populations. Herein, we review the environmental factors with the strongest association of sarcoma risk, including chemical exposure, certain viruses, cytotoxic and immunosuppressive agents, chronic edema, and radiation exposure. Additionally, the most common genetic disorders that carry a predisposition for sarcoma development will be discussed, including hereditary retinoblastoma (RB), Li-Fraumeni syndrome (LFS), neurofibromatosis type 1 (NF1), and DICER1 syndrome. Although treatment does not generally differ for sporadic versus secondary sarcomas, awareness of the risk factors can alter therapeutic strategies to minimize risk, aid prompt diagnosis by increasing clinical suspicion, and allow for appropriate surveillance and genetic counseling for those patients with cancer predisposition syndromes.
    DOI:  https://doi.org/10.1200/EDBK_280985
  3. Front Oncol. 2020 ;10 295
      Objective: Despite several nationwide cohort studies of germline BRCA1/2 mutations and several small cohort studies of somatic BRCA1/2 mutations in Chinese epithelial ovarian cancer (EOC) patients, little is known about the impact of these findings on survival outcomes in this population. In this study of 172 retrospectively recruited Chinese EOC patients, germline and somatic BRCA1/2 mutations and their value for predicting survival outcomes were evaluated. Methods: Unselected patients who visited the study center from January 1, 2011, to January 1, 2015, were recruited and asked to provide peripheral blood samples for this study if they were pathologically confirmed to have primary EOC. All patients received staging surgeries or debulking surgeries involving systemic platinum-based chemotherapy, and the patients were then followed up to December 1, 2017. DNA was extracted from formalin-fixed, paraffin-embedded (FFPE) sections and peripheral blood and sequenced for somatic and germline testing, respectively. The demographic and clinicopathological characteristics of the patients were collected to analyze the distribution of BRCA mutations in subgroups. Survival outcomes were compared among various BRCA mutation statuses using univariate and multivariate models. Results: In 58 (33.7%) patients, 63 variants were identified, including variants of unknown significance (VUS) in 18 patients (10.5%) and pathogenic or likely pathogenic variants in a partially overlapping set of 41 patients (23.8%). Germline BRCA mutations, somatic BRCA mutations, BRCA1 mutations in general, and BRCA2 mutations in general were found in 35 (20.3%), 7 (4.1%), 28 (16.3%), and 13 (7.6%) patients, respectively. Five recurrent mutations were identified. Personal and family cancer histories as well as hereditary breast and ovarian cancer (HBOC) criteria were associated with deleterious BRCA mutations both overall and in the germline specifically, whereas only age at diagnosis of EOC was associated with somatic BRCA mutations. In univariate and Cox regression analyses, patients with BRCA1/2 mutations in general had significant improvements in progression-free survival (PFS) and overall survival (OS). Conclusions: In Chinese EOC patients, the distributions and risk factors associated with germline and somatic BRCA1/2 mutations were similar to those previously reported in international studies. Deleterious BRCA mutations in general were associated with improved survival outcomes in this cohort.
    Keywords:  BRCA mutations; epithelial ovarian cancer; germline mutations; overall survival; progression-free survival; somatic mutations
    DOI:  https://doi.org/10.3389/fonc.2020.00295
  4. Gynecol Obstet Invest. 2020 Mar 23. 1-8
      OBJECTIVE: Germline BRCA mutation rates in the Latina population are yet to be well described. We aimed to quantitate the rates of referral for genetic testing in qualifying women and testing completion rates in a population of women presenting for gynecologic oncology care. Results were then stratified by ethnic/racial background.METHODS: Charts of new patients evaluated at a comprehensive cancer center in Southern California were reviewed. Patients qualifying for genetic testing in accordance with NCCN Guidelines version 1.2017 for breast and/or ovarian cancer genetic assessment were identified. The actual rates of prescriptions for genetic testing placed, testing completion rates, test results, as well as patients' family history were abstracted. Data were analyzed with chi-square tests.
    RESULTS: Five hundred and seventy-two of 2,053 patients met testing criteria, and 256/572 (45%) were prescribed testing in accordance with the guidelines. By ethnicity, testing was prescribed in 44% of Non-Hispanic White (NHW), 44% of Latina, 46% of African-American, and 60% of Asian (p = 0.6) patients. Testing was completed in 65% of NHW, 66% of Latina, 65% of African-American, and 67% of Asian patients (p = 0.97). Completion rates were low overall: 28% of those who met testing criteria were tested (p = 0.85). Pathogenic BRCA mutations were found in 29% of NHW and 21% of Latina, 45% of African-American, and 20% of Asian patients (p = 0.4).
    CONCLUSIONS: There was no difference by ethnicity in rates of testing prescription, completion, or presence of BRCA mutations. Overall, testing rates were suboptimal. BRCA mutations were found in large percentage of Latinas (21%). Further studies are underway to identify barriers to testing prescriptions and completion for Latina women.
    Keywords:  BRCA mutations; Genetic testing; Racial disparities
    DOI:  https://doi.org/10.1159/000506108
  5. Fam Cancer. 2020 Mar 21.
      A 14-year-old male presented with abdominal pain. Imaging illustrated a left-sided adrenal mass; he underwent a left nephrectomy, confirming an extra-adrenal PGL. Germline genetic testing revealed a heterozygous, likely pathogenic mutation in the SDHB gene. The patient's family subsequently underwent genetic testing; his mother and sister were both positive for the familial SDHB mutation. Cascade testing for the proband's maternal aunt and maternal grandparents was negative for the familial mutation. SNP genotyping was used to confirm relationships. This is the second reported case of a de novo SDHB gene mutation and the first reported case of a confirmed de novo mutation in a patient who was not the initial proband. As SDHB-associated PGLs and PCCs are expected to be more aggressive and malignant, it is imperative to identify patients with SDHB mutations early. Given that many patients with germline mutations have no family history of PGL of PCC, the possibility of de novo mutations must be considered. Further studies are needed to determine the rate of de novo mutation in SDHB and other SDH-complex genes. Up to 41% of patients with paragangliomas (PGL) or pheochromocytomas (PCC) have an identifiable hereditary cancer predisposition syndrome. Mutations in 12 genes are known to increase the risk of PGL and/or PCC; however, the de novo rate is mostly unknown. Only one case report exists of a de novo SDHB mutation. We present the second case of a family with a de novo SDHB mutation.
    Keywords:  Extra-adrenal; Hereditary; Paraganglioma; Pheochromocytoma; SDHB; de novo
    DOI:  https://doi.org/10.1007/s10689-020-00174-5
  6. J Clin Oncol. 2020 Mar 24. JCO1902808
      PURPOSE: Recently developed clinical guidelines suggest that men in families with specific cancer syndromes, such as hereditary breast and ovarian cancer (HBOC), consider genetic testing, especially in the setting of aggressive disease. However, although a family history (FH) of the same disease among close relatives is an established risk factor for prostate cancer (PC), a direct comparison of PC risk for men with each syndrome in a single population is needed.METHODS: The Utah Population Database was used to identify 619,630 men, age ≥ 40 years, who were members of a pedigree that included at least 3 consecutive generations. Each man was evaluated for FH of hereditary PC (HPC), HBOC, and Lynch syndrome (LS) and for his own PC status. PC occurrences (N = 36,360) were classified into one or more subtypes: early onset (EO), lethal, and/or clinically significant. Relative risks (RRs) associated with each subtype, adjusted for important covariables, were calculated in STATA using a modified Poisson regression with robust error variances to obtain corresponding RR CIs for each FH definition.
    RESULTS: An FH of HPC conveyed the greatest relative risk for all PC subtypes combined (RR, 2.30; 95% CI, 2.22 to 2.40), followed by HBOC and LS (both with 1 < RR < 2 and statistically significant). The strongest risks associated with FH were observed for EO disease in all pedigree types, consistent with the contribution of genetic factors to disease occurrence.
    CONCLUSION: In this large, population-based, family database, the risk of PC varied by cancer FH and was most strongly associated with EO disease. These results are critically valuable in understanding and targeting high-risk populations that would benefit from genetic screening and enhanced surveillance.
    DOI:  https://doi.org/10.1200/JCO.19.02808
  7. Front Genet. 2020 ;11 142
      Retinoblastoma (Rb) is a primary intraocular malignant tumor that occurs primarily in children, and results from loss-of-function mutations in the RB transcriptional corepressor 1 (RB1) gene. Genetic testing forms the basis of genetic counseling for affected families, as well as for clinical management of this disease. The aim of this study was to identify germline RB1 mutations and correlate the identified mutations with the clinical features of Rb patients. Genomic DNA was isolated from peripheral blood of 180 unrelated Rb patients and their parents (118 unilaterally and 62 bilaterally affected probands). Mutations in the RB1 gene, including the promoter region and exons 1-27 with flanking intronic sequences, were identified by Sanger sequencing. The samples with negative sequencing results were further subjected to methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) to detect gross deletions or duplications. Sixty-three distinct mutations were identified in 75 of the 180 (41.7%) probands. Of the 75 patients carrying RB1 mutations, 56 developed bilateral Rb, while 19 developed unilateral Rb. The total detection rates for bilateral and unilateral Rb were 90.3% (56/62) and 16.1% (19/118), respectively. Among the 75 patients, the spectrum of mutation types comprised 29.3% (22/75) nonsense mutations, 22.7% (17/75) splicing mutations, 17.3% (13/75) small insertions/deletions, 16.0% (12/75) large deletions/duplications, and 13.3% (10/75) missense mutations, while only 1% (1/75) of the mutations were in the promoter region of the RB1 gene. Age at diagnosis was significantly different (p < 0.01) between patients with positive and negative test results for germline RB1 mutations. A c.2359C > T mutation (p.R787X) was identified in identical twins, but one child was affected bilaterally and the other unilaterally. Of the five patients with deletion of the entire RB1 gene, the deletion of two patients was inherited from unaffected parents. In conclusion, in this study, we provide a comprehensive spectrum of RB1 germline mutations in Chinese Rb patients, and describe the correlations among RB1 mutations, age at diagnosis, and laterality; moreover, we report that the clinical features of individuals carrying an identical mutation in the RB1 gene were highly variable, indicating that the pathogenesis of Rb is more complicated than currently believed.
    Keywords:  RB1; clinical features; germline mutations; large deletion/duplication; retinoblastoma
    DOI:  https://doi.org/10.3389/fgene.2020.00142
  8. Fam Cancer. 2020 Mar 21.
      In this study we aim to determine the prevalence of the recently identified pathogenic BRCA1 variant c.-107A > T in the south-east German population. This variant causes the epigenetic silencing of the BRCA1 promotor and has been detected in two independent families from the UK without a germline BRCA1 or BRCA2 pathogenic variant. A total of 3297 individuals with suspicion of hereditary breast and ovarian cancer and fulfilling the clinical criteria necessary for genetic testing in Germany were analyzed for presence of the variant by a Kompetitive Allele-Specific PCR (KASP) assay or direct Sanger sequencing. Since we did not detect an individual carrying the variant we conclude that BRCA1 c.-107A > T is not a common variant in the south-east German population.
    Keywords:  5´UTR; BRCA1; KASP; c.-107A > T
    DOI:  https://doi.org/10.1007/s10689-020-00175-4
  9. Can Urol Assoc J. 2020 Mar 23.
      INTRODUCTION: Guidelines are available to assist providers in identifying patients with renal cell carcinoma (RCC) that may benefit from genetic counselling, however, the evidence for these recommendations lacks support from the literature and controversy remains as to who should be referred. We aimed to delineate risk factors associated with a positive genetic test in a real-life cohort of patients with RCC referred to a regional medical genetics unit for evaluation of a hereditary kidney cancer syndrome.METHODS: Patients with a diagnosis of RCC referred to Maritime Medical Genetics Service (Nova Scotia, Canada) from 2006-2017 were reviewed using retrospective data. The primary outcome was identification of clinical features that were associated with a positive test result. Logistic regression models were used for analysis.
    RESULTS: A total of 135 patients were referred to medical genetics for evaluation; 102 patients were evaluated, 75 underwent testing, and 74 were included in the final analysis. Five patients tested positive: three Birt Hogg Dube, one Cowden syndrome, and one Von Hippel Lindau. Presence of dermatological lesions (specifically fibrofolliculomas) and more than two high-risk features were the only predictors of a positive test result.
    CONCLUSIONS: The presence of dermatological lesions and more than two high-risk features are the only predictors of a positive test result in patients with a suspected hereditary kidney cancer syndrome. These findings are not reflected in current guidelines, and the clinical implementation of our results may improve the identification of high-risk patients for genetic counselling.
    DOI:  https://doi.org/10.5489/cuaj.6264
  10. J Hum Genet. 2020 Mar 18.
      BRCA1/2 genetic testing to use PARP inhibitor for breast cancer has a possibility of the "secondary finding" among the younger nonaffected family members of the patient, which turns them into at-risk for hereditary breast cancer. Proper understanding of the background of the hereditary cancer is now required for appropriate acceptance of the risk. Therefore, we investigated the level of knowledge and attitudes of younger women on hereditary breast cancer in Japan. Study subject was Japanese university women between 20 and 30 years of age, without medical history of breast cancer. We conducted the anonymous self-answering questionnaire to them. We received responses from 353 women. The levels of knowledge, awareness, and interest were relatively high. Women with a family history of breast cancer were less likely to undergo testing than women without (92.8% vs. 74.5%, p < 0.001). The rates of positive response toward risk-reducing mastectomy (RRM) and risk-reducing salpingo-oophorectomy (RRSO) was significantly high for medical majors compared with that for other majors (RRM: medical 71.6% vs. science 54.5% vs. humanities 53.8%, p = 0.008, RRSO: 35.4% vs. 36.3% vs. 48.4%, p = 0.027). Approximately half of respondents answered that they would hesitate to get married (45.3%) or to have children (55.4%), if they were a BRCA1/2 mutation carrier. The results may help to establish the methods for supporting the decision-making for reproduction of younger women who are unexpectedly labeled as being at-risk for HBOC.
    DOI:  https://doi.org/10.1038/s10038-020-0743-9