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.

Impact of an Expanded Definition of Family History on Outcomes of Active Surveillance for Prostate Cancer.

PURPOSE: Despite family history being an established risk factor for prostate cancer, the role of a broader definition of family history inclusive of not just prostate cancer but other genetically related malignancies has not been investigated in the active surveillance population. Here, we evaluate the impact of an expanded definition of family history on active surveillance outcomes. MATERIALS AND METHODS: Patients undergoing active surveillance for prostate cancer at Massachusetts General Hospital from 1997-2019 with detailed data available on family cancer history were identified. Primary outcome was biopsy progression-free survival, and secondary outcomes were treatment-free survival, adverse pathological features at prostatectomy, and biochemical recurrence after treatment. Statistical analyses were conducted using the Kaplan-Meier method and Cox regression. RESULTS: Among 855 evaluable patients, 300 (35.1%) patients had any family history of prostate cancer, and 95 (11.1%) had a family history of related malignancies suggestive of a hereditary cancer syndrome. Family history of prostate cancer alone was not associated with biopsy progression, whereas family history suggestive of a hereditary cancer syndrome was associated with a significantly increased risk of biopsy progression (HR 1.43, 95%CI 1.01-2.02), independent of other known clinicopathological risk factors in multivariable analysis. Similarly, family history suggestive of a hereditary cancer syndrome was associated with significantly lower treatment-free survival (HR 1.58, 95%CI 1.14-2.18) in multivariable analysis. No significant association was found between family history and adverse features on surgical pathology or biochemical recurrence. CONCLUSIONS: An expanded family history suggestive of a hereditary cancer syndrome is an independent predictor of biopsy progression during active surveillance. Men with such a family history may still be offered active surveillance but should be counseled regarding the higher risk of disease progression.

Motivation and family communication in hereditary prostate cancer genetic testing: Survey of patients from a US tertiary medical center.

Identification of a hereditary prostate cancer in an affected individual can guide treatment and may also impact cancer screening and surveillance for patients and their relatives. This study aimed to determine the factors that are associated with the decision-making process of individuals with prostate cancer regarding whether to pursue genetic testing as well as how, why, and with whom genetic test results are shared. We surveyed 113 patients diagnosed with prostate cancer who received cancer genetic counseling through a United States tertiary medical center, inquiring about genetic testing motivations and family communication about results. Among those who pursued genetic testing, (1) learning about my family's possible cancer risk (98%), (2) learning information that may guide cancer treatment (93%), and (3) learning if I am at risk for future cancers (92%) were most frequently identified as slightly or very important factors in their decision. Participants shared their genetic test results in a higher proportion to male first-degree relatives than female first-degree relatives; however, no significant difference was found (p = 0.103). Our study may suggest sex differences related to family communication about genetic testing results. Such findings indicate a critical need for genetic counselors to clearly communicate the impact of genetic test results on both male and female relatives. Further research on motivation and family communication about genetic test results in diverse cohorts is needed.

Transition to telephone genetic counseling services during the COVID-19 pandemic.

The COVID-19 pandemic has significantly disrupted the delivery of healthcare services, including oncology. To ensure continuity of cancer genetic counseling at a large academic medical center while also promoting the safety of patients and staff, our team transitioned to fully remote telephone genetic counseling and testing services within 48 hr. We compare differences in the six weeks following the shift to telephone genetic counseling (post-COVID) to the six weeks preceding the pandemic (pre-COVID). We maintained 99% of our total visit capacity and saw a decrease in patient no-show rate from 9.5% to 7.3%. Of all patients who received telephone genetic counseling, fewer consented to genetic testing as compared to patients seen in-person prior to the pandemic (79% pre-COVID v. 72% post-COVID; p = .012). Four weeks after this cohort was closed for analysis, 96 out of 303 samples (32%) had not been received by the genetic testing laboratory, despite at least one reminder phone call to the patient. In 13 reported instances, a second sample was required (quality not sufficient, lost or mislabeled sample), thus delaying test results. We conclude that a rapid transition to remote genetic counseling and testing allowed uninterrupted access to cancer genetics services during to the COVID-19 pandemic. Patient compliance with sample return and higher rates of sample failure emerge as potential barriers to timely genetic testing under this service delivery model.

Novel insights into breast cancer copy number genetic heterogeneity revealed by single-cell genome sequencing.

Copy number alterations (CNAs) play an important role in molding the genomes of breast cancers and have been shown to be clinically useful for prognostic and therapeutic purposes. However, our knowledge of intra-tumoral genetic heterogeneity of this important class of somatic alterations is limited. Here, using single-cell sequencing, we comprehensively map out the facets of copy number alteration heterogeneity in a cohort of breast cancer tumors. Ou/var/www/html/elife/12-05-2020/backup/r analyses reveal: genetic heterogeneity of non-tumor cells (i.e. stroma) within the tumor mass; the extent to which copy number heterogeneity impacts breast cancer genomes and the importance of both the genomic location and dosage of sub-clonal events; the pervasive nature of genetic heterogeneity of chromosomal amplifications; and the association of copy number heterogeneity with clinical and biological parameters such as polyploidy and estrogen receptor negative status. Our data highlight the power of single-cell genomics in dissecting, in its many forms, intra-tumoral genetic heterogeneity of CNAs, the magnitude with which CNA heterogeneity affects the genomes of breast cancers, and the potential importance of CNA heterogeneity in phenomena such as therapeutic resistance and disease relapse.

Cells in the body remain healthy by tightly preventing and repairing random changes, or mutations, in their genetic material. In cancer cells, however, these mechanisms can break down. When these cells grow and multiply, they can then go on to accumulate many mutations. As a result, cancer cells in the same tumor can each contain a unique combination of genetic changes. This genetic heterogeneity has the potential to affect how cancer responds to treatment, and is increasingly becoming appreciated clinically. For example, if a drug only works against cancer cells carrying a specific mutation, any cells lacking this genetic change will keep growing and cause a relapse. However, it is still difficult to quantify and understand genetic heterogeneity in cancer. Copy number alterations (or CNAs) are a class of mutation where large and small sections of genetic material are gained or lost. This can result in cells that have an abnormal number of copies of the genes in these sections. Here, Baslan et al. set out to explore how CNAs might vary between individual cancer cells within the same tumor. To do so, thousands of individual cancer cells were isolated from human breast tumors, and a technique called single-cell genome sequencing used to screen the genetic information of each of them. These experiments confirmed that CNAs did differ ­ sometimes dramatically ­ between patients and among cells taken from the same tumor. For example, many of the cells carried extra copies of well-known cancer genes important for treatment, but the exact number of copies varied between cells. This heterogeneity existed for individual genes as well as larger stretches of DNA: this was the case, for instance, for an entire section of chromosome 8, a region often affected in breast and other tumors. The work by Baslan et al. captures the sheer extent of genetic heterogeneity in cancer and in doing so, highlights the power of single-cell genome sequencing. In the future, a finer understanding of the genetic changes present at the level of an individual cancer cell may help clinicians to manage the disease more effectively.

Factors associated with referral and completion of genetic counseling in women with epithelial ovarian cancer.

OBJECTIVE: The National Comprehensive Cancer Network recommends that all women diagnosed with epithelial ovarian cancer undergo genetic testing, as the diagnosis of pathogenic variants may inform cancer survival and impact treatment options. The objective of this study was to assess factors associated with referral to genetic counseling in women with epithelial ovarian cancer. METHODS: A retrospective cohort study identified women with epithelial ovarian cancer from 2012 to 2017 at Massachusetts General Hospital and North Shore Medical Center, a community hospital affiliated with Massachusetts General Hospital. Multivariate logistic regression evaluated how race, age, stage, year of diagnosis, insurance status, family history of breast or ovarian cancer, and language relates to the receipt of genetic counseling. RESULTS: Of the total 276 women included, 73.9% were referred for genetic screening, of which 90.7% attended a genetic counseling visit. Older women were less likely to undergo genetic counseling (age ≥70 years: OR 0.26, 95% CI 0.07-0.94, p=0.04). Women who died within 365 days of initial oncology consult rarely reached a genetic counselor (OR 0.05, 95% CI 0.01-0.24, p<0.001). Women with a family history of breast or ovarian cancer were more likely to undergo counseling (OR 3.27, 95% CI 1.74-6.15, p<0.001). There was no difference in receipt of genetic counseling by race, stage, year of diagnosis, insurance status, or language. CONCLUSION: Older women with epithelial ovarian cancer and those who died within 1 year of initiation of care were less likely to undergo recommended genetic counseling. Race, insurance status, and language were not identified as predictive factors, although we were limited in this assessment by small sample size.

Universal screening of both endometrial and colon cancers increases the detection of Lynch syndrome.

BACKGROUND: Lynch syndrome (LS) is the most common hereditary cause of colorectal cancer (CRC) and endometrial cancer (EC). Screening of all CRCs for LS is currently recommended, but screening of ECs is inconsistent. The objective of this study was to determine the added value of screening both CRC and EC tumors in the same population. METHODS: A prospective, immunohistochemistry (IHC)-based screening program for all patients with newly diagnosed CRCs and ECs was initiated in 2011 and 2013, respectively, at 2 centers (primary and tertiary). Genetic testing was recommended for those who had tumors with absent mutS homolog 2 (MSH2), MSH6, or postmeiotoic segregation increased 2 (PMS2) expression and for those who had tumors with absent mutL homolog 1 (MLH1) expression and no v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutation or MLH1 promoter methylation. Amsterdam II criteria, revised Bethesda criteria, and scores from prediction models for gene mutations (the PREMM1,2,6 and PREMM5 prediction models) were ascertained in patients with LS. RESULTS: In total, 1290 patients with CRC and 484 with EC were screened for LS, and genetic testing was recommended for 137 patients (10.6%) and 32 patients (6.6%), respectively (P = .01). LS was identified in 16 patients (1.2%) with CRC and in 8 patients (1.7%) with EC. Among patients for whom genetic testing was recommended, the LS diagnosis rate was higher among those with EC (25.0% vs 11.7%, P = .052). The Amsterdam II criteria, revised Bethesda criteria, and both PREMM calculators would have missed 62.5%, 50.0%, and 12.5% of the identified patients with LS, respectively. CONCLUSIONS: Expanding a universal screening program for LS to include patients who had EC identified 50% more patients with LS, and many of these patients would have been missed by risk assessment tools (including PREMM5 ). Universal screening programs for LS should include both CRC and EC. Cancer 2018. © 2018 American Cancer Society.

Utility of Single-Cell Genomics in Diagnostic Evaluation of Prostate Cancer.

A distinction between indolent and aggressive disease is a major challenge in diagnostics of prostate cancer. As genetic heterogeneity and complexity may influence clinical outcome, we have initiated studies on single tumor cell genomics. In this study, we demonstrate that sparse DNA sequencing of single-cell nuclei from prostate core biopsies is a rich source of quantitative parameters for evaluating neoplastic growth and aggressiveness. These include the presence of clonal populations, the phylogenetic structure of those populations, the degree of the complexity of copy-number changes in those populations, and measures of the proportion of cells with clonal copy-number signatures. The parameters all showed good correlation to the measure of prostatic malignancy, the Gleason score, derived from individual prostate biopsy tissue cores. Remarkably, a more accurate histopathologic measure of malignancy, the surgical Gleason score, agrees better with these genomic parameters of diagnostic biopsy than it does with the diagnostic Gleason score and related measures of diagnostic histopathology. This is highly relevant because primary treatment decisions are dependent upon the biopsy and not the surgical specimen. Thus, single-cell analysis has the potential to augment traditional core histopathology, improving both the objectivity and accuracy of risk assessment and inform treatment decisions.Significance: Genomic analysis of multiple individual cells harvested from prostate biopsies provides an indepth view of cell populations comprising a prostate neoplasm, yielding novel genomic measures with the potential to improve the accuracy of diagnosis and prognosis in prostate cancer. Cancer Res; 78(2); 348-58. ©2017 AACR.

Whole-genome single-cell copy number profiling from formalin-fixed paraffin-embedded samples.

A substantial proportion of tumors consist of genotypically distinct subpopulations of cancer cells. This intratumor genetic heterogeneity poses a substantial challenge for the implementation of precision medicine. Single-cell genomics constitutes a powerful approach to resolve complex mixtures of cancer cells by tracing cell lineages and discovering cryptic genetic variations that would otherwise be obscured in tumor bulk analyses. Because of the chemical alterations that result from formalin fixation, single-cell genomic approaches have largely remained limited to fresh or rapidly frozen specimens. Here we describe the development and validation of a robust and accurate methodology to perform whole-genome copy-number profiling of single nuclei obtained from formalin-fixed paraffin-embedded clinical tumor samples. We applied the single-cell sequencing approach described here to study the progression from in situ to invasive breast cancer, which revealed that ductal carcinomas in situ show intratumor genetic heterogeneity at diagnosis and that these lesions may progress to invasive breast cancer through a variety of evolutionary processes.

A tailored approach to BRAF and MLH1 methylation testing in a universal screening program for Lynch syndrome.

To determine the correlation between BRAF genotype and MLH1 promoter methylation in a screening program for Lynch syndrome (LS), a universal screening program for LS was established in two medical centers. Tumors with abnormal MLH1 staining were evaluated for both BRAF V600E genotype and MLH1 promoter methylation. Tumors positive for both were considered sporadic, and genetic testing was recommended for all others. A total 1011 colorectal cancer cases were screened for Lynch syndrome, and 148 (14.6%) exhibited absent MLH1 immunostaining. Both BRAF and MLH1 methylation testing were completed in 126 cases. Concordant results (both positive or both negative) were obtained in 86 (68.3%) and 16 (12.7%) cases, respectively, with 81% concordance overall. The positive and negative predictive values for a BRAF mutation in predicting MLH1 promoter methylation were 98.9% and 41%, respectively, and the negative predictive value fell to 15% in patients ≥70 years old. Using BRAF genotyping as a sole test to evaluate cases with absent MLH1 staining would have increased referral rates for genetic testing by 2.3-fold compared with MLH1 methylation testing alone (31% vs 13.5%, respectively, P<0.01). However, a hybrid approach that reserves MLH1 methylation testing for BRAF wild-type cases only would significantly decrease the number of methylation assays performed and reduce the referral rate for genetic testing to 12.7%. A BRAF mutation has an excellent positive predictive value but poor negative predictive value in predicting MLH1 promoter methylation. A hybrid use of these tests may reduce the number of low-risk patients referred to genetic counseling and facilitate wider implementation of Lynch syndrome screening programs.

SMASH, a fragmentation and sequencing method for genomic copy number analysis.

Copy number variants (CNVs) underlie a significant amount of genetic diversity and disease. CNVs can be detected by a number of means, including chromosomal microarray analysis (CMA) and whole-genome sequencing (WGS), but these approaches suffer from either limited resolution (CMA) or are highly expensive for routine screening (both CMA and WGS). As an alternative, we have developed a next-generation sequencing-based method for CNV analysis termed SMASH, for short multiply aggregated sequence homologies. SMASH utilizes random fragmentation of input genomic DNA to create chimeric sequence reads, from which multiple mappable tags can be parsed using maximal almost-unique matches (MAMs). The SMASH tags are then binned and segmented, generating a profile of genomic copy number at the desired resolution. Because fewer reads are necessary relative to WGS to give accurate CNV data, SMASH libraries can be highly multiplexed, allowing large numbers of individuals to be analyzed at low cost. Increased genomic resolution can be achieved by sequencing to higher depth.

The Influence of Microdeletions and Microduplications of 16p11.2 on Global Transcription Profiles.

Copy number variants (CNVs) of a 600 kb region on 16p11.2 are associated with neurodevelopmental disorders and changes in brain volume. The authors hypothesize that abnormal brain development associated with this CNV can be attributed to changes in transcriptional regulation. The authors determined the effects of 16p11.2 dosage on gene expression by transcription profiling of lymphoblast cell lines derived from 6 microdeletion carriers, 15 microduplication carriers and 15 controls. Gene dosage had a significant influence on the transcript abundance of a majority (20/34) of genes within the CNV region. In addition, a limited number of genes were dysregulated in trans. Genes most strongly correlated with patient head circumference included SULT1A, KCTD13, and TMEM242. Given the modest effect of 16p11.2 copy number on global transcriptional regulation in lymphocytes, larger studies utilizing neuronal cell types may be needed in order to elucidate the signaling pathways that influence brain development in this genetic disorder.

Optimizing sparse sequencing of single cells for highly multiplex copy number profiling.

Genome-wide analysis at the level of single cells has recently emerged as a powerful tool to dissect genome heterogeneity in cancer, neurobiology, and development. To be truly transformative, single-cell approaches must affordably accommodate large numbers of single cells. This is feasible in the case of copy number variation (CNV), because CNV determination requires only sparse sequence coverage. We have used a combination of bioinformatic and molecular approaches to optimize single-cell DNA amplification and library preparation for highly multiplexed sequencing, yielding a method that can produce genome-wide CNV profiles of up to a hundred individual cells on a single lane of an Illumina HiSeq instrument. We apply the method to human cancer cell lines and biopsied cancer tissue, thereby illustrating its efficiency, reproducibility, and power to reveal underlying genetic heterogeneity and clonal phylogeny. The capacity of the method to facilitate the rapid profiling of hundreds to thousands of single-cell genomes represents a key step in making single-cell profiling an easily accessible tool for studying cell lineage.

The contribution of de novo coding mutations to autism spectrum disorder.

Whole exome sequencing has proven to be a powerful tool for understanding the genetic architecture of human disease. Here we apply it to more than 2,500 simplex families, each having a child with an autistic spectrum disorder. By comparing affected to unaffected siblings, we show that 13% of de novo missense mutations and 43% of de novo likely gene-disrupting (LGD) mutations contribute to 12% and 9% of diagnoses, respectively. Including copy number variants, coding de novo mutations contribute to about 30% of all simplex and 45% of female diagnoses. Almost all LGD mutations occur opposite wild-type alleles. LGD targets in affected females significantly overlap the targets in males of lower intelligence quotient (IQ), but neither overlaps significantly with targets in males of higher IQ. We estimate that LGD mutation in about 400 genes can contribute to the joint class of affected females and males of lower IQ, with an overlapping and similar number of genes vulnerable to contributory missense mutation. LGD targets in the joint class overlap with published targets for intellectual disability and schizophrenia, and are enriched for chromatin modifiers, FMRP-associated genes and embryonically expressed genes. Most of the significance for the latter comes from affected females.

Clinical applications of melanoma genetics.

Families that have several relatives with melanoma, multiple primary melanomas in one individual, younger than average ages of melanoma onset, and/or the presence of both pancreatic cancer and melanoma may be suggestive of a hereditary melanoma syndrome and are candidates for genetic counseling and risk assessment. Genetic counseling for hereditary melanoma presents many complexities. Only a minority of hereditary melanoma cases have been attributed to a single genetic factor, CDKN2A. Both the frequency and the penetrance of CDKN2A mutations has been shown to be dependent on multiple factors. The clinical utility of genetic testing for hereditary melanoma families is debatable because CDKN2A status may not impact medical management in patients with melanoma. No standard medical management guidelines exist for families with CDKN2A mutations; however, family history of melanoma and pancreatic cancer may warrant further discussion. Clinicians should discuss the clinical and psychological implications before genetic testing. Genetic counseling and pretest education regarding melanoma risk factors provides an opportunity to increase knowledge and understanding of melanoma risk, while addressing psychological risks and concerns.

De novo gene disruptions in children on the autistic spectrum.

Exome sequencing of 343 families, each with a single child on the autism spectrum and at least one unaffected sibling, reveal de novo small indels and point substitutions, which come mostly from the paternal line in an age-dependent manner. We do not see significantly greater numbers of de novo missense mutations in affected versus unaffected children, but gene-disrupting mutations (nonsense, splice site, and frame shifts) are twice as frequent, 59 to 28. Based on this differential and the number of recurrent and total targets of gene disruption found in our and similar studies, we estimate between 350 and 400 autism susceptibility genes. Many of the disrupted genes in these studies are associated with the fragile X protein, FMRP, reinforcing links between autism and synaptic plasticity. We find FMRP-associated genes are under greater purifying selection than the remainder of genes and suggest they are especially dosage-sensitive targets of cognitive disorders.

Genome-wide copy number analysis of single cells.

Copy number variation (CNV) is increasingly recognized as an important contributor to phenotypic variation in health and disease. Most methods for determining CNV rely on admixtures of cells in which information regarding genetic heterogeneity is lost. Here we present a protocol that allows for the genome-wide copy number analysis of single nuclei isolated from mixed populations of cells. Single-nucleus sequencing (SNS), combines flow sorting of single nuclei on the basis of DNA content and whole-genome amplification (WGA); this is followed by next-generation sequencing to quantize genomic intervals in a genome-wide manner. Multiplexing of single cells is discussed. In addition, we outline informatic approaches that correct for biases inherent in the WGA procedure and allow for accurate determination of copy number profiles. All together, the protocol takes ∼3 d from flow cytometry to sequence-ready DNA libraries.

Which individuals undergoing BRACAnalysis need BART testing?

Deleterious mutations in BRCA1 and BRCA2 include those identified by sequencing technology as well as large genomic rearrangements (LGR). The main testing laboratory in the United States, Myriad Genetics Laboratory (MGL), has defined criteria for inclusion of LGR testing (i.e., BRACAnalysis Rearrangement Test, or BART™) when BRCA1 and BRCA2 testing is ordered. We were interested in determining how many of our patients with LGR mutations in BRCA1 and BRCA2 fulfilled these MGL criteria. A retrospective chart review was performed on all individuals who underwent genetic testing at our institution since August 2006. Individuals who underwent LGR testing were classified as either having or not having a LGR in BRCA1 or BRCA2. Each individual's history was classified as meeting MGL defined LGR criteria, meeting criteria using third-degree relatives, or not meeting criteria. A total of 257 BART tests were ordered at our institution from August 2006 to August 2009. Five individuals (1.9%) had an LGR mutation. Two LGR were identified in patients who met MGL defined LGR criteria. One LGR was identified in a patient that met MGL defined LGR criteria only when using third-degree relatives. Two LGR were identified in individuals who did not meet MGL defined criteria. LGR are present in individuals who do not have a high pretest probability of carrying a mutation in BRCA1 or BRCA2. These data suggest that when BRCA1 and BRCA2 genetic testing is performed, testing should always include LGR testing so that the results are the most comprehensive and reliable.