Multigene Panel Sequencing Research Articles

Multicenter study on the genetics of glomerular diseases among southeast and south Asians: Deciphering Diversities ‐ Renal Asian Genetics Network (DRAGoN)

Multinational studies have reported monogenic etiologies in 25%-30% of children with steroid-resistant nephrotic syndrome. Such large studies are lacking in Asia. We established Deciphering Diversities: Renal Asian Genetics Network (DRAGoN) and aimed to describe the genetic and clinical spectrums in Asians. We prospectively studied a cohort of 183 probands with suspected genetic glomerulopathies from South and Southeast Asia, of whom 17% had positive family history. Using multi-gene panel sequencing, we detected pathogenic variants in 26 (14%) probands, of whom one-third had COL4A4 or COL4A5 variants (n=9, 5%). Of those with COL4A5 defects, only 25% had features suggestive of Alport syndrome. Besides traditional predictors for genetic disease (positive family history and extrarenal malformations), we identified novel predictors, namely older age (6.2 vs. 2.4 years; p=0.001), hematuria (OR 5.6; 95% CI 2.1-14.8; p < 0.001), and proteinuria in the absence of nephrotic syndrome (OR 4.6; 95% CI 1.8-11.8; p=0.001) at first manifestation. Among patients who first presented with proteinuria without nephrotic syndrome, the genetic diagnostic rates were >60% when a second risk factor (positive family history or extrarenal manifestation) co-existed. The genetic spectrum of glomerulopathies appears different in Asia. Collagen IV genes may be included in sequencing panels even when suggestive clinical features are absent.

REGISTRIES AND CARE OF NMD: EP.347 Development of a standard of care for patients with valosin-containing protein associated multisystem proteinopathy

Valosin-containing protein (VCP) associated multisystem proteinopathy (MSP) is a rare inherited disorder with a reported incidence of 0.66/100,000 based on population data from the UK. VCP-associated MSP may result in multisystem involvement of varying presentations and phenotypes including inclusion body myopathy, Paget's disease of bone, frontotemporal dementia, parkinsonism, and amyotrophic lateral sclerosis, among others. An international multidisciplinary consortium of 50+ experts in neuromuscular disease, dementia, psychology, cardiology, pulmonology, physical therapy, occupational therapy, speech and language pathology, nutrition, genetics, and endocrinology were convened by the patient advocacy organization, Cure VCP Disease, in 2021 to elicit collaboration and development of a standard of care for this rare and under-diagnosed disease. To achieve this goal, working groups were established to generate best evidence recommendations in 10 key areas: genetics and diagnosis, myopathy, frontotemporal dementia, Paget's disease of bone, ALS and CMT, parkinsonism, cardiomyopathy, supportive therapies, pulmonology, nutrition and supplements, and mental health. In April 2021, facilitated discussion of each working group's conclusion with consensus building techniques enabled final agreement on the recommended standard of care for patients with VCP-associated MSP. Timely referral to a specialty neuromuscular center is recommended to aid in efficient diagnosis of VCP-associated MSP via single-gene testing in the case of a known familial VCP variant, or multi-gene panel sequencing in undifferentiated cases. Additionally, regular and ongoing multidisciplinary team follow up is essential for proactive screening and management of the secondary complications. The goal of our consortium is to raise awareness of VCP-associated MSP, to expedite the time to accurate diagnosis and elevate the recommended best practices guidelines for multidisciplinary care internationally.

Genotype and phenotype distribution of 435 patients with Charcot–Marie–Tooth disease from central south China

The purpose was to provide an overview of genotype and phenotype distribution in a cohort of patients with Charcot-Marie-Tooth disease (CMT) and related disorders from central south China. In all, 435 patients were enrolled and detailed clinical data were collected. Multiplex ligation-dependent probe amplification for PMP22 duplication/deletion and CMT multi-gene panel sequencing were performed. Whole exome sequencing was further applied in the remaining patients who failed to achieve molecular diagnosis. Among the 435 patients, 216had CMT1, 14had hereditary neuropathy with pressure palsies (HNPP), 178had CMT2, 24had distal hereditary motor neuropathy (dHMN) and threehad hereditary sensory and autonomic neuropathy (HSAN). The overall molecular diagnosis rate was 70%: 75.7% in CMT1, 100% in HNPP, 64.6% in CMT2, 41.7% in dHMN and 33.3% in HSAN. The most common four genotypes accounted for 68.9% of molecular diagnosed patients. Relatively frequent causes were missense changes in PMP22 (4.6%) and SH3TC2 (2.3%) in CMT1; and GDAP1 (5.1%), IGHMBP2 (4.5%) and MORC2 (3.9%) in CMT2. Twenty of 160 detected pathogenic variants and the associated phenotypes have not been previously reported. Broad phenotype spectra were observed in six genes, amongst which the pathogenic variants in BAG3 and SPTLC1 were detected in two sporadic patients presenting with the CMT2 phenotype. Our results provided a unique genotypic and phenotypic landscape of patients with CMT and related disorders from central south China, including a relatively high proportion of CMT2 and lower occurrence of PMP22 duplication. The broad phenotype spectra in certain genes have advanced our understanding of CMT.

Prevalence and Clinicopathological Characteristics of Moderate and High-Penetrance Genes in Non-BRCA1/2 Breast Cancer High-Risk Spanish Families.

(1) Background: Over the last decade, genetic counseling clinics have moved from single-gene sequencing to multigene panel sequencing. Multiple genes related to a moderate risk of breast cancer (BC) have emerged, although many questions remain regarding the risks and clinical features associated with these genes. (2) Methods: Ninety-six BC index cases (ICs) with high-risk features for hereditary breast and ovarian cancer (HBOC) and with a previous uninformative result for BRCA1/2 were tested with a panel of 41 genes associated with BC risk. The frequency of pathogenic variants (PVs) was related to the clinical characteristics of BC. (3) Results: We detected a PV rate of 13.5% (excluding two cases each of BRCA1 and MUTYH). Among the 95 assessed cases, 17 PVs were identified in 16 ICs, as follows: BRCA1 (n = 2), CHEK2 (n = 3), ATM (n = 5), MUTYH (n = 2), TP53 (n = 2), BRIP1 (n = 1), CASP8 (n = 1), and MSH2 (n = 1). We also identified a novel loss-of-function variant in CASP8, a candidate gene for increased BC risk. There was no evidence that the clinical characteristics of BC might be related to a higher chance of identifying a PV. (4) Conclusions: In our cohort, which was enriched with families with a high number of BC cases, a high proportion of mutations in ATM and CHEK2 were identified. The clinical characteristics of BC associated with moderate-risk genes were different from those related to BRCA1/2 genes.

Cancer predisposition in pediatric neuro-oncology-practical approaches and ethical considerations.

A genetic predisposition to tumor development can be identified in up to 10% of pediatric patients with central nervous system (CNS) tumors. For some entities, the rate of an underlying predisposition is even considerably higher. In recent years, population-based approaches have helped to further delineate the role of cancer predisposition in pediatric oncology. Investigations for cancer predisposition syndrome (CPS) can be guided by clinical signs and family history leading to directed testing of specific genes. The increasingly adopted molecular analysis of tumor and often parallel blood samples with multi-gene panel, whole-exome, or whole-genome sequencing identifies additional patients with or without clinical signs. Diagnosis of a genetic predisposition may put an additional burden on affected families. However, information on a given cancer predisposition may be critical for the patient as potentially influences treatment decisions and may offer the patient and healthy carriers the chance to take part in intensified surveillance programs aiming at early tumor detection. In this review, we discuss some of the practical and ethical challenges resulting from the widespread use of new diagnostic techniques and the most important CPS that may manifest with brain tumors in childhood.

Clinical Contribution of Next-Generation Sequencing Multigene Panel Testing for BRCA Negative High-Risk Patients With Breast Cancer

BackgroundBreast cancer is the most common malignancy in women and thought to be hereditary in 10% of patients. Recent next-generation sequencing studies have increased the detection of pathogenic or likely pathogenic (P/LP) variants in genes other than BRCA1/2 in patients with breast cancer. This study evaluated pathogenic variants, likely pathogenic variants, and variants of unknown significance in 18 hereditary cancer susceptibility genes in patients with BRCA1/2-negative breast cancer. Patients and MethodsThis retrospective study included 188 high-risk BRCA1/2-negative patients with breast cancer tested with a multigene cancer panel using next-generation sequencing. ResultsAmong 188 proband cases, 18 variants in 21 patients (11.1%) were classified as P/LP in PALB2 (n = 6), CHEK2 (n = 5), MUTYH (n = 4), ATM (n = 3), TP53 (n = 2), BRIP1 (n = 1), and MSH2 (n = 1). Three novel P/LP variants were identified. An additional 28 variants were classified as variants of unknown significance and detected in 30 different patients (15.9%). ConclusionThis is one of the largest study from Turkey to investigate the mutation spectrum in non-BRCA hereditary breast cancer susceptibility genes. A multigene panel test increased the likelihood of identifying a molecular diagnosis in patients with BRCA 1/2-negative breast cancer at risk for a hereditary breast cancer syndrome. More studies are needed to enable the clinical interpretation of these P/LP variants in hereditary patients with breast cancer.

Genetic investigation of 211 Chinese families expands the mutational and phenotypical spectra of hereditary retinopathy genes through targeted sequencing technology

BackgroundHereditary retinopathy is a significant cause of blindness worldwide. Despite the discovery of many mutations in various retinopathies, a large number of patients remain genetically undiagnosed. Targeted next-generation sequencing of the human genome is a suitable approach for the molecular diagnosis of retinopathy.MethodsWe describe a cohort of 211 families from central China with various forms of retinopathy; 95 patients were investigated using multigene panel sequencing, and the other 116 with suspected Leber hereditary optic neuropathy (LHON) were tested by Sanger sequencing. The detected variation of targeted sequencing was verified by PCR-based Sanger sequencing. We performed a comprehensive analysis of the cases using sequencing data and ophthalmologic examination information.ResultsPotential causal mutations were identified in the majority of families with retinopathy (57.9% of 95 families) and suspected LHON (21.6% of 116 families). There were 68 variants of a certain significance distributed in 31 known disease-causing genes in the 95 families; 37 of the variants are novel and have not been reported to be related to hereditary retinopathy. The NGS panel solution provided a 45.3% potential diagnostic rate for retinopathy families, with candidate gene mutations of undefined pathogenicity revealed in another 12.6%of the families.ConclusionOur study uncovered novel mutations and phenotypic aspects of retinopathy and demonstrated the genetic and clinical heterogeneity of related conditions. The findings show the detection rate of pathogenic variants in patients with hereditary retinopathy in central China as well as the diversity and gene distribution of these variants. The significance of molecular genetic testing for patients with hereditary retinopathy is also highlighted.

Targeted sequencing panels in Italian ALS patients support different etiologies in the ALS/FTD continuum

Background5–10% of amyotrophic lateral sclerosis (ALS) patients presented a positive family history (fALS). More than 30 genes have been identified in association with ALS/frontotemporal dementia (FTD) spectrum, with four major genes accounting for 60–70% of fALS. In this paper, we aimed to assess the contribution to the pathogenesis of major and rare ALS/FTD genes in ALS patients.MethodsWe analyzed ALS and ALS/FTD associated genes by direct sequencing or next-generation sequencing multigene panels in ALS patients.ResultsGenetic abnormalities in ALS major genes included repeated expansions of hexanucleotide in C9orf72 gene (7.3%), mutations in SOD1 (4.9%), FUS (2.1%), and TARDBP (2.4%), whereas variants in rare ALS/FTD genes affected 15.5% of subjects overall, most frequently involving SQSTM1 (3.4%), and CHMP2B (1.9%). We found clustering of variants in ALS major genes in patients with a family history for “pure” ALS, while ALS/FTD related genes mainly occurred in patients with a family history for other neurodegenerative diseases (dementia and/or parkinsonism).ConclusionsOur data support the presence of two different genetic components underlying ALS pathogenesis, related to the presence of a family history for ALS or other neurodegenerative diseases. Thus, family history may help in optimizing the genetic screening protocol to be applied.

Genetic and metabolic investigations for individuals with neurodevelopmental disorders: A survey of Canadian geneticists' practices

Neurodevelopmental disorders (NDDs) are genetically heterogeneous. There are many possible etiological investigations for NDDs, and a lack of clear and current guidelines for such testing. Here we characterize the practices of genetic and metabolic physicians in Canada as it pertains to etiological investigation of patients with NDDs, by means of an online questionnaire. The survey response rate was 30% (n = 46). The most commonly ordered first-line tests for patients with non-syndromic NDDs are chromosomal microarray (98%) and Fragile X testing (85%). The most commonly ordered second-line test for non-syndromic NDDs is a multi-gene panel (78%) or exome sequencing (29%). Biochemical screening is ordered as a first line test by 33% of respondents, second line by 31%, and rarely or never by 36% of respondents. Those respondents with metabolics fellowship training were more likely to order biochemical screening than those without. The number of years of clinical experience generally did not affect the types of tests ordered. For patients with NDDs, test-ordering practice among Canadian clinical geneticists is highly variable, in particular with respect to biochemical screening and use of next-generation sequencing technologies. Evidence-based guidelines should be developed to facilitate best practices in Canada.

A multidisciplinary approach for the differential diagnosis between multiple primary lung adenocarcinomas and intrapulmonary metastases

PurposeThe distinction between multiple primary lung cancers (MPLCs) and intrapulmonary metastases has a significant impact on tumor staging and therapeutic choices. Several criteria have been proposed to solve this diagnostic issue, but a definitive consensus is still missing. We tested the efficacy of a combined clinical, histopathological and molecular (“real world”) approach for the correct classification of multiple lung tumors in a selected cohort of patients. Methods24 multiple lung tumors with a diagnosis of adenocarcinoma from 10 patients were retrospectively reviewed. Radiological, pathological and clinical information, including follow-up, were integrated with molecular profiling via a routine multigene panel sequencing. ResultsComprehensive histologic assessment revealed readily distinguishable histologic patterns between multiple tumors suggesting unrelated lesions in 7 cases, in agreement with clinical, radiological and molecular data, thus leading to final diagnosis of MPLCs. In the remaining 3 cases, the differential diagnosis between MPLCs and intrapulmonary metastases was challenging, since the histologic features of the lesions were similar or identical. The final interpretation (2 MPLCs and 1 most likely intrapulmonary metastases) was reached thanks to the integration of all available data, and was confirmed by follow-up. ConclusionsA multidisciplinary approach including a routinely affordable multigene panel sequencing is a useful tool to discriminate MPLCs from intrapulmonary metastases in multiple lung nodules sharing the adenocarcinoma histotype.

The results of multigene panel sequencing in Slovak HBOC families.

Hereditary breast and ovarian cancer (HBOC) is primarily associated with mutations in the BRCA1/2 genes. However, causal variants in other high, moderate, and low penetrance genes proportionally increase the risk of breast/ovarian cancer. This study aims to provide data about the mutation spectrum of HBOC-associated genes in Slovak HBOC families and estimate the ratio of BRCA versus non-BRCA causal variants. We used panel sequencing containing 22 high/moderate-risk susceptibility genes and parallel MLPA analysis of BRCA1/2, CHEK2 genes, to analyze 94 individuals with a strong family/personal history of breast and/or ovarian cancer. The analyzed group consisted of 80 patients diagnosed with cancer (85.1%) and 14 healthy individuals (14.9%) with a positive family history of HBOC syndrome. In total, we have identified 22 causal DNA variants (23.4%) showing 15 primary findings in BRCA1/2 genes (68.2%) and 7 positive secondary findings in CHEK2, PALB2, CDH1, and MUTYH genes (31.8%). The most frequent pathogenic alterations were BRCA1 mutations c.181T>G and CNV variant (c.5573-?_c.5701+?)del, known as deletion of exons 21-22. Besides known mutations, the BRCA1 variant c.2794del (p.Val932Leufs*68) and variant c.2480dup (p.Tyr827*) in the CDH1 gene represent the novel, previously unpublished variants that might be population-specific. In conclusion, we provide the first report of multigene panel testing in Slovak HBOC families demonstrating that almost one-third of pathogenic mutations are situated in susceptibility genes other than BRCA1/2. Although multigene panel testing requires precise data filtration and interpretation, it might bring the relevant data for clinical management of the patients.

Customised next-generation sequencing multigene panel to screen a large cohort of individuals with chromatin-related disorder

BackgroundThe regulation of the chromatin state by epigenetic mechanisms plays a central role in gene expression, cell function, and maintenance of cell identity. Hereditary disorders of chromatin regulation are a...

Epileptic Encephalopathies of Childhood: The New Paradigm of Genetic Diagnosis

Epileptic encephalopathies of childhood are characterized by early seizure-onset and adverse neurological outcomes. The development of new genetic techniques has allowed an exponential identification of the genes that are involved. Over the last years, we have observed a revolution in the diagnostic paradigm. However, there are no international guidelines regarding the diagnosis of genetic epileptic encephalopathies. We aim to discuss the current knowledge about the genetic architecture of epileptic encephalopathies of childhood. review of the literature about infantile epileptic encephalopathies and the genetic tests currently available. A systematic approach and a diagnostic algorithm to use in clinical practice were proposed. Initially the patient's phenotype should be determined based on the seizure type, electroencephalogram pattern and neuroimaging. Patients with unclear etiology after brain magnetic resonance imaging should undergo an appropriate metabolic investigation to promptly exclude treatable conditions. Further studies should also include other genetic causes, mainly if associated with particular phenotypic features. Chromosomal microarray analysis should be firstly considered, particularly if dysmorphic or polymalformative abnormalities are present. If this is negative and/or there are no physical features, the next step should be next-generation sequencing multigene panels or whole-exome sequencing. Single gene study should only be considered when the patient's phenotype is highly suggestive of a specific syndrome. The revolution of the genetic knowledge about epileptic encephalopathies of childhood has led to a complex diagnostic approach. This new paradigm poses significant implications in genetic counselling, treatment and prognosis.

Cost-effectiveness of genomic profiling in veterans with metastatic lung adenocarcinoma.

7075 Background: Tumor profiling identifies patients who are eligible for targeted anticancer therapies. Common tumor profiling approaches include targeted gene panel testing (TGPT), which tests for common mutations in select genes, and multigene panel sequencing (MGPS), which tests for a broad range of mutations in a comprehensive set of genes. Our objective was to determine the lifetime cost-effectiveness of MGPS and TGPT compared to no tumor profiling for Veterans with metastatic lung adenocarcinoma from the Veterans Health Administration’s (VHA) perspective. Methods: A decision analytic model was developed to simulate outcomes for a closed cohort of hypothetical Veterans with metastatic lung adenocarcinoma considering anticancer therapy. OncoKB genes with levels of evidence 1 and 2 for guiding therapy were included. Three profiling strategies were studied: TGPT ( ALK, EGFR, ROS1), MGPS ( ALK, BRAF, EGFR, HER2, MET, NTRK1, NTRK2, NTRK3, RET, ROS1), and no tumor profiling. We assumed 95% of patients with actionable mutations received targeted therapies. Non-targeted therapy options included chemotherapy and/or immunotherapy, and no anticancer therapy. Model inputs were derived from randomized trials (progression-free survival), VHA and Medicare (drug costs), published studies (non-drug cancer-related management costs, health care utilities), and VHA National Precision Oncology Program and cBioPortal for Cancer Genomics databases (mutation prevalence). Costs (2019 US$) and quality-adjusted life years (QALYs) were discounted at 3%/year. Base-case scenario, one-way sensitivity analyses, and probabilistic sensitivity analyses (PSA) using 1,000 Monte Carlo simulations were completed. Results: Base-case results and corresponding 95% credible intervals from the PSA indicated the cost/QALY gained was $309,399 ($280,371-$343,161) for TGPT and $324,707 ($296,086-$359,778) for MGPS compared to no tumor profiling. Of the 3 strategies, MGPS resulted in the highest number of QALYs. One-way sensitivity analyses revealed the cost/QALY estimates were most impacted by changes in health state utility on a targeted therapy (quality of life), costs of alectinib, and non-drug cancer-related costs in patients receiving targeted therapy. Compared to no tumor profiling, cost-effectiveness ratios for both profiling approaches surpassed the $150,000/QALY threshold in 100% of PSA simulations. Conclusions: Tumor profiling (TGPT or MGPS) can optimize anticancer therapy selection in patients with metastatic lung adenocarcinoma and improve quality-adjusted survival, but compared to no tumor profiling, is not cost-effective.

Value of multigene panel retesting of families with BRCA1/2 mutation-negative hereditary breast and ovarian cancer (HBOC).

1582 Background: Despite the use of clinical eligibility criteria and mutation predictive models, a great proportion of families are negative for germline mutations in BRCA1/2 genes. Traditionally, risk assessment of inconclusive results included the recommendation of high-risk surveillance protocol, the update of incident cancer cases in the family and the consideration of additional testing to rule out the possibility of phenocopy. More recently, next generation sequencing multigene panels have become a standard practice in cancer genetics clinics worldwide. We addressed the value of multigene panel retesting of BRCA1/2 negative HBOC families in our institution. Methods: After genetic counseling session and informed consent, a total of 137 individuals (119 probands and 18 extra cancer-affected relatives) from distinct BRCA1/2 negative families were retested using a panel containing 11 breast and ovarian cancer susceptibility genes ( BRCA1/2, PALB2, ATM, CHEK2, PTEN, TP53, STK11, BRIP1, RAD51C, RAD51D). Results: According to the BOADICEA model, the remaining probability of mutation in BRCA1/2 or PALB2 genes in our cohort was 5.5% (0.1-61). The reasons for considering retesting were the addition of any incident cancer diagnosis in 33 cases (24%), a prior study with a low sensitivity screening technique (dHPLC) in 6 families (5%) and the expansion of the study to other putative breast and ovarian susceptibility genes in 98 families (71%). Overall, 3 pathogenic (2 BRCA2, 1 CHEK2) and 8 likely pathogenic variants (1 BRCA2, 4 CHEK2 and 3 ATM) were found. The prevalence was 8%. The detection rate among 19 families with a &gt; 10% remaining probability of mutation in BRCA1/2 and PALB2 genes was 26%. The 3 clinically significant variants in BRCA2 were detected in 2 families and 1 updated cancer family history (BOADICEA remaining probability of 59, 61 and 12%, respectively). Cascade testing was subsequently done in 15 relatives resulting 8 in mutation carriers and 9 true negatives. Conclusions: Our results support the value of updating cancer incident cases and considering expanded panels in selected families.

Clinical Multigene Panel Sequencing Identifies Distinct Mutational Association Patterns in Metastatic Colorectal Cancer.

Extensive molecular characterization of human colorectal cancer (CRC) via Next Generation Sequencing (NGS) indicated that genetic or epigenetic dysregulation of a relevant, but limited, number of molecular pathways typically occurs in this tumor. The molecular picture of the disease is significantly complicated by the frequent occurrence of individually rare genetic aberrations, which expand tumor heterogeneity. Inter- and intratumor molecular heterogeneity is very likely responsible for the remarkable individual variability in the response to conventional and target-driven first-line therapies, in metastatic CRC (mCRC) patients, whose median overall survival remains unsatisfactory. Implementation of an extensive molecular characterization of mCRC in the clinical routine does not yet appear feasible on a large scale, while multigene panel sequencing of most commonly mutated oncogene/oncosuppressor hotspots is more easily achievable. Here, we report that clinical multigene panel sequencing performed for anti-EGFR therapy predictive purposes in 639 formalin-fixed paraffin-embedded (FFPE) mCRC specimens revealed previously unknown pairwise mutation associations and a high proportion of cases carrying actionable gene mutations. Most importantly, a simple principal component analysis directed the delineation of a new molecular stratification of mCRC patients in eight groups characterized by non-random, specific mutational association patterns (MAPs), aggregating samples with similar biology. These data were validated on a The Cancer Genome Atlas (TCGA) CRC dataset. The proposed stratification may provide great opportunities to direct more informed therapeutic decisions in the majority of mCRC cases.

Direct-to-consumer misleading information on cancer risks calls for an urgent clarification of health genetic testing performed by commercial companies

Direct-to-consumer (DTC) commercial companies offer genetic tests that are presented as allowing individuals the opportunity to increase their capacities to be in charge of their own healthcare managements. DTC companies deny performing medical tests, yet they provide data based on sequencing multigene panel or whole exome. This contradiction allows these companies to escape the requirements of a regulated medical practice that guarantees the quality of the tests, as well as the information and support for tested individuals. Herein, we illustrate the lack of such requirements by analysing the bad experience of a young man who dealt with DTC health genetic testing companies. There is an emergency for DTC testing to be either deprived of any medically relevant information, or carried out in a legally regulated medical framework.

Mutation landscape of germline and somatic BRCA1/2 in patients with high-grade serous ovarian cancer

BackgroundPoly (ADP-ribose) polymerase inhibitors targeting BRCA1/2 mutations are available for treating patients with high-grade serous ovarian cancer. These treatments may be more appropriately directed to patients who might respond if the tumor tissue is additionally tested by next-generation sequencing with a multi-gene panel and Sanger sequencing of a blood sample. In this study, we compared the results obtained using the next-generation sequencing multi-gene panel to a known germline BRCA1/2 mutational state determined by conventional Sanger sequencing to evaluate the landscape of somatic mutations in high-grade serous ovarian cancer tumors.MethodsCancer tissue from 98 patients with high-grade serous ovarian cancer who underwent Sanger sequencing for germline BRCA1/2 analysis were consecutively analyzed for somatic mutations using a next-generation sequencing 170-gene panel.ResultsTwenty-four patients (24.5%) showed overall BRCA1/2 mutations. Seven patients (7.1%) contained only somatic BRCA1/2 mutations with wild-type germline BRCA1/2, indicating acquired mutation of BRCA1/2. Three patients (3.1%) showed reversion of germline BRCA1 mutations. Among the 14 patients (14.3%) with both germline and somatic mutations in BRCA1/2, two patients showed different variations of BRCA1/2 mutations. The next-generation sequencing panel test for somatic mutation detected other pathogenic variations including RAD51D and ARID1A, which are possible targets of poly (ADP-ribose) polymerase inhibitors. Compared to conventional Sanger sequencing alone, next-generation sequencing-based tissue analysis increased the number of candidates for poly (ADP-ribose) polymerase inhibitor treatment from 17.3% (17/98) to 26.5% (26/98).ConclusionsSomatic mutation analysis by next-generation sequencing, in addition to germline BRCA1/2 mutation analysis, should become the standard of care for managing women with high-grade serous ovarian cancer to widen the indication of poly (ADP-ribose) polymerase inhibitors.

Cost Effectiveness of Multigene Panel Sequencing for Patients With Advanced Non-Small-Cell Lung Cancer.

Compared with single-marker genetic testing (SMGT), multigene panel sequencing (MGPS) has the potential to identify more patients with cancer who could benefit from targeted therapies, but the effects on outcome and total cost of care are uncertain. Our goal was to estimate the clinical and cost effectiveness of MGPS versus SMGT among patients with advanced non-small-cell lung cancer (aNSCLC). Patients with aNSCLC-stage IIIB or metastatic-who were diagnosed between 2011 and 2016 were identified from the Flatiron Health database. After stratifying patients into MGPS or SMGT cohorts, we analyzed the percentage of patients who received targeted treatment, survival, and total costs of care. SMGT included epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase testing. MGPS also allowed for the detection of BRAF, RET, ROS1, HER2, and MET mutations. Cost data sources were the Centers for Medicare & Medicaid Services Fee Schedule and 2017 average sales price drug cost. We estimated the incremental cost-effectiveness ratio from a US payer perspective over a lifetime horizon using a decision model. We identified 5,688 patients with aNSCLC who received MGPS (n = 875) or SMGT (n = 4,813), of which 22% tested positive for epidermal growth factor receptor (18.5% MGPS; 17.3% SMGT) or anaplastic lymphoma kinase (3.59% MGPS; 3.78% SMGT). Among MGPS-tested patients, an additional 8% were found to have BRAF, RET, ROS1, HER2, or MET mutations. Of MGPS-tested patients, 21% received treatments that were targeted to the specific mutations versus 19% with SMGT. Expected survival was 1.14 life years (LYs) in SMGT versus 1.20 LYs in MGPS. Lifetime total costs were $8,814 higher per patient for MGPS. The incremental cost-effectiveness ratio of MGPS versus SMGT was $148,478 per LY gained. On the basis of data from a nationwide oncology patient database, MGPS is shown to have moderate cost effectiveness compared with SMGT in patients with aNSCLC.

Identification of germline pathogenic variants in DNA damage repair genes by a next-generation sequencing multigene panel in BRCAX patients

BackgroundApproximately 5–10% of breast carcinomas have been related to hereditary conditions and are attributable to pathogenic variants in the BRCA1 and BRCA2 genes, which is referred to as hereditary breast and ovarian cancer (HBOC) syndrome. The inclusion of additional genes that can be related to HBOC syndrome is under intense evaluation due to the high proportion of patients with HBOC criteria who do not present pathogenic mutations in BRCA genes, named BRCAX, despite having high clinical suspicion of hereditary cancer. The main aim is to identify new potentially pathogenic gene variants that may contribute to HBOC to improve the efficiency of routine diagnostic tests in this hereditary condition. MethodsA retrospective cohort of 77 HBOC BRCAX patients was analyzed by next-generation sequencing using a targeted multigene panel composed of 25 genes related to hereditary cancer and deficiencies in DNA repair pathways. ResultsWe found 9 variants in 7 different genes, which were confirmed by automated sequencing. Six variants were classified as pathogenic or likely pathogenic. Three of them were located in the PALB2 gene, one in the BRIP1 gene, one in the BARD1 gene and 1 in the RAD50 gene. In addition, three variants of uncertain significance (VUS) were detected in the TP53, CHEK2, and CDH1 genes. ConclusionsWe identified that 8% of BRCAX patients were carriers of pathogenic variants in genes other than BRCA1 and BRCA2. Therefore, wide gene panels, including clinically actionable genes, should be routinely used in the screening of HBOC in our population. We observed differences from other studies in the prevalence of mutated genes, most likely due to differences in the selection criteria of the probands and in the population analyzed. The high incidence of deleterious variant detection in PALB2 supports its significant role in breast cancer susceptibility and reinforces its inclusion in the HBOC genetic diagnostic process.