Germline BRCA2 pathogenic variants in pediatric ganglioglioma: Case report and review of the literature

BACKGROUND

BRCA1 and BRCA2 are tumor suppressor genes associated with increased risk of breast and ovarian cancer in adulthood. Patients with germline pathogenic variants in these genes have also been reported to develop brain tumors, although it is unclear whether these syndromes are associated with significant increased risk of brain tumor formation.

RESULTS

Here, we report a case of a child with germline BRCA2 pathogenic variant presenting with a symptomatic ganglioglioma. To our knowledge, this is the first such patient to be reported. We discuss prior cases of brain tumors in BRCA1/2 patients and evidence for a potential role for BRCA1/2 pathogenic variants in brain tumor formation.

CONCLUSION

BRCA2 germline variants may increase the risk of developing some types of pediatric brain tumors, but further study is needed to determine its effect on low-grade glioma formation.

Magnetic Resonance Imaging-based Prostate Cancer Screening in Carriers of Pathogenic Germline Mutations: Interim Results from the Initial Screening Round of the Prostate Cancer Genetic Risk Evaluation and Screening Study

BACKGROUND

The risk of early-onset and clinically aggressive prostate cancer is elevated in carriers of certain rare pathogenic germline mutations. The utility of augmenting traditional prostate-specific antigen (PSA)-based screening measures with multiparametric magnetic resonance imaging (MRI) in this population is not yet known.

OBJECTIVE

To evaluate MRI-based screening in comparison with traditional PSA-based screening among individuals at an elevated genetic risk for prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

Male germline carriers of pathogenic/likely pathogenic variants in any of 19 prostate cancer risk genes between the ages of 35 and 74 yr with no prior history of prostate cancer were recruited. Intervention Enrolled participants underwent screening with annual PSA, digital rectal examination (DRE), and triennial multiparametric MRI. Individuals with abnormal DRE, elevated age-adjusted PSA (>1.5 ng/ml for 35-49 yr, >2.0 ng/ml for 50-54 yr, and >3.0 ng/ml for 55-74 yr), or suspicious multiparametric MRI (Prostate Imaging Reporting and Data System [PI-RADS] ≥3 lesion) were offered prostate biopsy. Outcome measurements and statistical analysis Endpoints were diagnosis of any and clinically significant prostate cancer, and alternative screening strategies were compared by a decision curve analysis.

RESULTS AND LIMITATIONS

To date, 101 males have completed the first round of screening. The greatest proportion of participants are carriers of BRCA2 (n = 44), BRCA1 (n = 35), and ATM (n = 7) variants. Twenty-one have undergone biopsy, resulting in the detection of nine cases of cancer (seven clinically significant). For the detection of clinically significant prostate cancer, abnormal MRI (PI-RADS ≥3) demonstrated 100% sensitivity (7/7) with a negative predictive value (NPV) of 100%, whereas PSA-based screening alone had 57% (4/7) sensitivity with an NPV of 73%. Of six screening strategies evaluated in the decision curve analysis, MRI-based screening alone achieved superior net benefit at all threshold probabilities compared with PSA screening-detecting one additional cancer case per 7.5 patients, while avoiding more unnecessary biopsies at the same threshold probability.

CONCLUSIONS

Disease prevalence is high among carriers of prostate cancer-associated pathogenic germline mutations. Early results suggest that MRI-based screening enhances early detection of clinically significant disease beyond PSA screening alone.

PATIENT SUMMARY

In this study, we present the interim results from the PROGRESS prostate cancer screening trial. We found that in certain germline carriers of prostate cancer risk mutations, magnetic resonance imaging-based screening enhances detection of prostate cancer while reducing biopsies triggered, in comparison with traditional prostate-specific antigen screening strategies.

Inherited BRCA1 and RNF43 pathogenic variants in a familial colorectal cancer type X family

Genetic susceptibility to familial colorectal cancer (CRC), including for individuals classified as Familial Colorectal Cancer Type X (FCCTX), remains poorly understood. We describe a multi-generation CRC-affected family segregating pathogenic variants in both BRCA1, a gene associated with breast and ovarian cancer and RNF43, a gene associated with Serrated Polyposis Syndrome (SPS). A single family out of 105 families meeting the criteria for FCCTX (Amsterdam I family history criteria with mismatch repair (MMR)-proficient CRCs) recruited to the Australasian Colorectal Cancer Family Registry (ACCFR; 1998-2008) that underwent whole exome sequencing (WES), was selected for further testing. CRC and polyp tissue from four carriers were molecularly characterized including a single CRC that underwent WES to determine tumor mutational signatures and loss of heterozygosity (LOH) events. Ten carriers of a germline pathogenic variant BRCA1:c.2681_2682delAA p.Lys894ThrfsTer8 and eight carriers of a germline pathogenic variant RNF43:c.988 C > T p.Arg330Ter were identified in this family. Seven members carried both variants, four of which developed CRC. A single carrier of the RNF43 variant met the 2019 World Health Organization (WHO2019) criteria for SPS, developing a BRAF p.V600 wildtype CRC. Loss of the wildtype allele for both BRCA1 and RNF43 variants was observed in three CRC tumors while a LOH event across chromosome 17q encompassing both genes was observed in a CRC. Tumor mutational signature analysis identified the homologous recombination deficiency (HRD)-associated COSMIC signatures SBS3 and ID6 in a CRC for a carrier of both variants. Our findings show digenic inheritance of pathogenic variants in BRCA1 and RNF43 segregating with CRC in a FCCTX family. LOH and evidence of BRCA1-associated HRD supports the importance of both these tumor suppressor genes in CRC tumorigenesis.

A comprehensive characterisation of phaeochromocytoma and paraganglioma tumours through histone protein profiling, DNA methylation and transcriptomic analysis genome wide

BACKGROUND

Phaeochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumours. Pathogenic variants have been identified in more than 15 susceptibility genes; associated tumours are grouped into three Clusters, reinforced by their transcriptional profiles. Cluster 1A PPGLs have pathogenic variants affecting enzymes of the tricarboxylic acid cycle, including succinate dehydrogenase. Within inherited PPGLs, these are the most common. PPGL tumours are known to undergo epigenetic reprograming, and here, we report on global histone post-translational modifications and DNA methylation levels, alongside clinical phenotypes.

RESULTS

Out of the 25 histone post-translational modifications examined, Cluster 1A PPGLs were distinguished from other tumours by a decrease in hyper-acetylated peptides and an increase in H3K4me2. DNA methylation was compared between tumours from individuals who developed metastatic disease versus those that did not. The majority of differentially methylated sites identified tended to be completely methylated or unmethylated in non-metastatic tumours, with low inter-sample variance. Metastatic tumours by contrast consistently had an intermediate DNA methylation state, including the ephrin receptor EPHA4 and its ligand EFNA3. Gene expression analyses performed to identify genes involved in metastatic tumour behaviour pin-pointed a number of genes previously described as mis-regulated in Cluster 1A tumours, as well as highlighting the tumour suppressor RGS22 and the pituitary tumour-transforming gene PTTG1.

CONCLUSIONS

Combined transcriptomic and DNA methylation analyses revealed aberrant pathways, including ones that could be implicated in metastatic phenotypes and, for the first time, we report a decrease in hyper-acetylated histone marks in Cluster 1 PPGLs.

A de Novo BRCA1 Pathogenic Variant in a 29-Year-Old Woman with Triple-Negative Breast Cancer

Introduction

Germline pathogenic variants in the BRCA1 and BRCA2 genes lead to a highly increased lifetime risk for breast and ovarian cancer. These variants are usually inherited and reports of de novo occurrences are a very rare phenomenon.

Case Presentation

We report on a breast cancer patient with a de novo BRCA1 variant c.121C>T (p.His41Tyr). The pathogenic variant was detected in leukocyte DNA of a patient with negative family history who had developed early onset, triple-negative breast cancer. The variant was not found in any of the maternal and paternal tissues tested, but it was detected in multiple samples representing all three germ layers of the affected carrier, which renders somatic mosaicism unlikely.

Conclusion

This case highlights the importance of including early onset of disease and triple negativity of the tumor as criteria for genetic testing, even in patients without family history. Considering the availability of effective breast cancer treatments in patients with pathogenic variants in the BRCA genes, this finding underscores the importance of genetic testing in breast cancer patients.

Prevalence and Risk Factors of Germline Pathogenic Variants in Pancreatic Ductal Adenocarcinoma

PURPOSE

The genetic attribution for pancreatic ductal adenocarcinoma (PDAC) has been reported as 5%-10%. However, the incidence of germline pathogenic variants (PVs) in Korean PDAC patients has not been thoroughly investigated. Therefore, we studied to identify the risk factors and prevalence of PV for future treatment strategies in PDAC.

MATERIALS AND METHODS

Total of 300 (155 male) patients with a median age of 65 years (range, 33 to 90 years) were enrolled in National Cancer Center in Korea. Cancer predisposition genes, clinicopathologic characteristics, and family history of cancer were analyzed.

RESULTS

PVs were detected in 20 patients (6.7%, median age 65) in ATM (n=7, 31.8%), BRCA1 (n=3, 13.6%), BRCA2 (n=3), and RAD51D (n=3). Each one patient showed TP53, PALB2, PMS2, RAD50, MSH3, and SPINK1 PV. Among them, two likely PVs were in ATM and RAD51D, respectively. Family history of various types of cancer including pancreatic cancer (n=4) were found in 12 patients. Three patients with ATM PVs and a patient with three germline PVs (BRCA2, MSH3, and RAD51D) had first-degree relatives with pancreatic cancer. Familial pancreatic cancer history and PVs detection had a significant association (4/20, 20% vs. 16/264, 5.7%; p=0.035).

CONCLUSION

Our study demonstrated that germline PVs in ATM, BRCA1, BRCA2, and RAD51D are most frequent in Korean PDAC patients and it is comparable to those of different ethnic groups. Although this study did not show guidelines for germline predisposition gene testing in patients with PDAC in Korea, it would be emphasized the need for germline testing for all PDAC patients.

Spectrum of germline pathogenic variants using a targeted next generation sequencing panel and genotype-phenotype correlations in patients with suspected hereditary breast cancer at an academic medical centre in Pakistan

Background

Breast cancer is the most common malignancy in women, affecting over 1.5 million women every year, which accounts for the highest number of cancer-related deaths in women globally.

Hereditary breast cancer (HBC), an important subset of breast cancer, accounts for 5–10% of total cases. However, in Low Middle-Income Countries (LMICs), the population-specific risk of HBC in different ethnicities and the correlation with certain clinical characteristics remain unexplored.

Methods

Retrospective chart review of patients who visited the HBC clinic and proceeded with multi-gene panel testing from May 2017 to April 2020.

Descriptive and inferential statistics were used to analyze clinical characteristics of patients. Fisher’s exact, Pearson’s chi-squared tests and Logistic regression analysis were used for categorical variables and Wilcoxon rank-sum test were used for quantitative variables. For comparison between two independent groups, Mann-Whitney test was performed. Results were considered significant at a p value of < 0.05.

Results

Out of 273 patients, 22% tested positive, 37% had a VUS and 41% had a negative genetic test result. Fifty-five percent of the positive patients had pathogenic variants in either BRCA1 or BRCA2, while the remaining positive results were attributed to other genes. Patients with a positive result had a younger age at diagnosis compared to those having a VUS and a negative result; median age 37.5 years, IQR (Interquartile range) (31.5–48). Additionally, patients with triple negative breast cancer (TNBC) were almost 3 times more likely to have a positive result (OR = 2.79, CI = 1.42–5.48 p = 0.003). Of all patients with positive results, 25% of patients had a negative family history of breast and/or related cancers.

Conclusions

In our HBC clinic, we observed that our rate of positive results is comparable, yet at the higher end of the range which is reported in other populations. The importance of expanded, multi-gene panel testing is highlighted by the fact that almost half of the patients had pathogenic or likely pathogenic variants in genes other than BRCA1/2, and that our test positivity rate would have only been 12.8% if only BRCA1/2 testing was done. As the database expands and protocol-driven referrals are made across the country, our insight about the genetic architecture of HBC in our population will continue to increase.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13053-022-00232-2.

Influential Factors on Risk-reduction Mastectomy in a High-risk Breast Cancer Population With Genetic Predispositions

BACKGROUND

Carriers of deleterious mutations in breast cancer predisposition genes are presented with critical choices regarding cancer risk management. Risk-reduction mastectomy is a major preventative strategy in this population. Understanding the decision-making process for prophylactic mastectomy is essential in patient-centered care for high-risk carriers and patients with breast cancer. We sought to provide insight into influential factors underlying preventative surgery decisions among individuals with high breast cancer risk.

MATERIALS AND METHODS

We conducted a retrospective chart review of pathogenic carriers of high-risk breast cancer genes who presented to the Moffitt GeneHome clinic between March 2017 and June 2020. Associations between preventative mastectomy choice and influence variables were analyzed via unadjusted and adjusted logistic regression models.

RESULTS

Of 258 high-risk mutation carriers, 104 (40.3%) underwent risk-reduction mastectomy. A significantly higher proportion of mastectomy patients reported prior history of breast cancer (68.9% vs. 16.5%; P < .001) and history of other risk-reduction or noncancer-related surgeries (61.7% vs. 25.8%; P < .001). Significant predictors affecting surgery decision included previous breast cancer history (adjusted odds ratio [aOR], 10.48; 95% confidence interval [CI], 5.59-19.63; P < .0001), other risk-reduction or noncancer-related surgical history (aOR, 4.65; 95% CI, 2.28-9.47; P < .0001), and age at presentation to the genetics clinic (< 35 years old: aOR, 2.77; 95% CI, 1.04-7.4; P = .042; 35-55 years old: aOR, 2.48; 95% CI, 1.19-5.18; P = .016).

CONCLUSIONS

Preventive mastectomy decisions are highly personal and complex. In our sample, we observed prior history or concurrent breast cancer, history of other risk-reduction surgery or noncancer-related surgery, and younger age at presentation to the GeneHome clinic to be predictive of mastectomy uptake.