Selection of Germline Genetic Testing Panels in Patients With Cancer: ASCO Guideline

PURPOSE

To guide use of multigene panels for germline genetic testing for patients with cancer.

METHODS

An ASCO Expert Panel convened to develop recommendations on the basis of a systematic review of guidelines, consensus statements, and studies of germline and somatic genetic testing.

RESULTS

Fifty-two guidelines and consensus statements met eligibility criteria for the primary search; 14 studies were identified for Clinical Question 4.

RECOMMENDATIONS

Patients should have a family history taken and recorded that includes details of cancers in first- and second-degree relatives and the patient's ethnicity. When more than one gene is relevant based on personal and/or family history, multigene panel testing should be offered. When considering what genes to include in the panel, the minimal panel should include the more strongly recommended genes from Table 1 and may include those less strongly recommended. A broader panel may be ordered when the potential benefits are clearly identified, and the potential harms from uncertain results should be mitigated. Patients who meet criteria for germline genetic testing should be offered germline testing regardless of results from tumor testing. Patients who would not normally be offered germline genetic testing based on personal and/or family history criteria but who have a pathogenic or likely pathogenic variant identified by tumor testing in a gene listed in Table 2 under the outlined circumstances should be offered germline testing.Additional information is available at www.asco.org/molecular-testing-and-biomarkers-guidelines.

Exploring Stakeholders' Perspectives on Implementing Universal Germline Testing for Colorectal Cancer: Findings From a Clinical Practice Survey

PURPOSE

New guidelines recommend considering germline genetic testing for all patients with colorectal cancer (CRC). However, there is a lack of data on stakeholders' perspectives on the advantages and barriers of implementing universal germline testing (UGT). This study assessed the perspectives of members of the Collaborative Group of the Americas on Inherited Gastrointestinal Cancer (CGA-IGC) regarding the implementation of UGT for patients with CRC, including readiness, logistics, and barriers.

METHODS

A cross-sectional survey was sent to 317 active members of CGA-IGC. The survey included sections on demographics, clinical practice specialty, established institutional practices for testing, and questions pertaining to support of and barriers to implementing UGT for patients with CRC.

RESULTS

Eighty CGA-IGC members (25%) participated, including 42 genetic counselors (53%) and 14 gastroenterologists (18%). Forty-seven (59%) reported an academic medical center as their primary work setting, and most participants (56%) had more than 10 years of clinical practice. Although most participants (73%) supported UGT, 54% indicated that changes in practice would be required before adopting UGT, and 39% indicated that these changes would be challenging to implement. There was support for both genetics and nongenetics providers to order genetic testing, and a majority (57%) supported a standardized multigene panel rather than a customized gene panel. Key barriers to UGT implementation included limited genetics knowledge among nongenetics providers, time-consuming processes for obtaining consent, ordering tests, disclosing results, and lack of insurance coverage.

CONCLUSION

This study demonstrates wide support among hereditary GI cancer experts for implementation of UGT for patients with CRC. However, alternative service delivery models using nongenetics providers should be considered to address the logistical barriers to UGT implementation, particularly the growing demand for genetic testing.

Priorities to Promote Participant Engagement in the Participant Engagement and Cancer Genome Sequencing (PE-CGS) Network

BACKGROUND

Engaging diverse populations in cancer genomics research is of critical importance and is a fundamental goal of the NCI Participant Engagement and Cancer Genome Sequencing (PE-CGS) Network. Established as part of the Cancer Moonshot, PE-CGS is a consortium of stakeholders including clinicians, scientists, genetic counselors, and representatives of potential study participants and their communities. Participant engagement is an ongoing, bidirectional, and mutually beneficial interaction between study participants and researchers. PE-CGS sought to set priorities in participant engagement for conducting the network's research.

METHODS

PE-CGS deliberatively engaged its stakeholders in the following four-phase process to set the network's research priorities in participant engagement: (i) a brainstorming exercise to elicit potential priorities; (ii) a 2-day virtual meeting to discuss priorities; (iii) recommendations from the PE-CGS External Advisory Panel to refine priorities; and (iv) a virtual meeting to set priorities.

RESULTS

Nearly 150 PE-CGS stakeholders engaged in the process. Five priorities were set: (i) tailor education and communication materials for participants throughout the research process; (ii) identify measures of participant engagement; (iii) identify optimal participant engagement strategies; (iv) understand cancer disparities in the context of cancer genomics research; and (v) personalize the return of genomics findings to participants.

CONCLUSIONS

PE-CGS is pursuing these priorities to meaningfully engage diverse and underrepresented patients with cancer and posttreatment cancer survivors as participants in cancer genomics research and, subsequently, generate new discoveries.

IMPACT

Data from PE-CGS will be shared with the broader scientific community in a manner consistent with participant informed consent and community agreement.

Perspectives on Spanish language concordant cancer genetic counseling sessions from the Spanish-speaking population

Genetic counselors (GCs) provide risk assessment, education, and counseling about the genetic contribution to disease. To do so, they must effectively communicate, build rapport, and help patients make the best decisions for themselves and their families. Language barriers add a complex layer to this patient-provider dynamic. While interpreters serve as a primary solution when a patient and GC speak different languages, issues have been documented with these sessions, such as misinterpreted genetic terminology (Gutierrez et al., 2017). Having a GC with concordant language skills may help address these barriers. The purpose of this study was to assess Spanish-speaking patients' perspectives on communication, decision-making, and the interpersonal relationship developed with a bilingual GC in language concordant cancer genetic counseling sessions. Spanish-speaking patients, ages 18 or older, seen by a Spanish-speaking GC at a California public, safety-net hospital were eligible to participate in this study. Nine participants were interviewed via telephone by the bilingual researcher using a semi-structured interview guide to assess three domains: communication, decision-making, and interpersonal relationship. Analyses of interview transcripts identified themes within these three areas of focus: (1) participants felt all explanations were clear and they were not afraid to ask questions in the session, (2) participants experienced preference-concordant decision making, and (3) participants felt empowered and supported by the GC. Participants suggested that GCs working with Spanish-speaking patients in the future should consider group counseling sessions, engaging in outreach efforts to educate the Spanish-speaking community about genetics, and increasing the number of GCs who speak Spanish. These results demonstrate the positive experiences of Spanish-speaking patients in language concordant cancer genetic counseling sessions and further support the need for recruitment of Spanish-speaking individuals into the profession. Future research should further assess the experience of Spanish-speaking patients in language concordant sessions and address the role of cultural concordance in sessions.

Behavioral beliefs about genetic counseling among high-risk Latina breast cancer survivors in Florida and Puerto Rico

Compared with non-Hispanic White women, Latina women are less likely to receive genetic counseling (GC) and testing (GT) following BC diagnosis. This study used secondary data analysis to explore beliefs about GC among Latina BC survivors in and outside the US mainland. GC/GT-naïve, high-risk, Spanish-preferring Latina BC survivors (n = 52) in FL and PR completed the Behavioral Beliefs about GC scale. Participants reported high positive beliefs about GC (M = 4.19, SD = 0.92); the majority agreed that GC was beneficial to understand cancer risk (90%) and promote discussion (87%) in their family. Participants reported low-to-moderate scores for barriers (Ms = 1.53-3.40; SDs = 0.59-0.90). The most frequently endorsed barriers were desire for additional GC information (M = 3.44; SD = 0.90), and GC logistic concerns (M = 2.71; SD = 0.80). No statistically significant differences for barriers and benefits scales were identified by place of residence (all ps ≥ 0.12). These findings highlight the importance of delivering culturally sensitive GC information to high-risk Latina BC survivors.

Whole exome sequencing and replication for breast cancer among Hispanic/Latino women identifies FANCM as a susceptibility gene for estrogen-receptor-negative breast cancer

Introduction

Breast cancer (BC) is one of the most common cancers globally. Genetic testing can facilitate screening and risk-reducing recommendations, and inform use of targeted treatments. However, genes included in testing panels are from studies of European-ancestry participants. We sequenced Hispanic/Latina (H/L) women to identify BC susceptibility genes.

Methods

We conducted a pooled BC case-control analysis in H/L women from the San Francisco Bay area, Los Angeles County, and Mexico (4,178 cases and 4,344 controls). Whole exome sequencing was conducted on 1,043 cases and 1,188 controls and a targeted 857-gene panel on the remaining samples. Using ancestry-adjusted SKAT-O analyses, we tested the association of loss of function (LoF) variants with overall, estrogen receptor (ER)-positive, and ER-negative BC risk. We calculated odds ratios (OR) for BC using ancestry-adjusted logistic regression models. We also tested the association of single variants with BC risk.

Results

We saw a strong association of LoF variants in FANCM with ER-negative BC (p=4.1×10-7, OR [CI]: 6.7 [2.9-15.6]) and a nominal association with overall BC risk. Among known susceptibility genes, BRCA1 (p=2.3×10-10, OR [CI]: 24.9 [6.1-102.5]), BRCA2 (p=8.4×10-10, OR [CI]: 7.0 [3.5-14.0]), and PALB2 (p=1.8×10-8, OR [CI]: 6.5 [3.2-13.1]) were strongly associated with BC. There were nominally significant associations with CHEK2, RAD51D, and TP53.

Conclusion

In H/L women, LoF variants in FANCM were strongly associated with ER-negative breast cancer risk. It previously was proposed as a possible susceptibility gene for ER-negative BC, but is not routinely tested in clinical practice. Our results demonstrate that FANCM should be added to BC gene panels.

Integration of Universal Germline Genetic Testing for All New Breast Cancer Patients

BACKGROUND

The American Society of Breast Surgeons recommends genetic testing (GT) for all women with breast cancer (BC), but implementation and uptake of GT has not been well-described.

METHODS

A retrospective chart review was performed for newly diagnosed BC patients or patients with a newly identified recurrence of BC seen in a multidisciplinary clinic (MDBC) who were offered genetic counseling (GC) and GT.

RESULTS

The 138 women attending the MDBC had a median age of 54 years and comprised non-Hispanic whites (46%), Asians (28%), Hispanics (17%), blacks (4%), and other (5%). Of the 105 (76%) patients without prior GT, 100 (95%) accepted GC, with 93 (93%) of these 100 patients undergoing GT. The patients meeting the National Comprehensive Cancer Network (NCCN) guidelines for GT were more likely to undergo GT. Testing was performed with a 67- to 84-gene panel, together with an 8- to 9-gene STAT panel if needed. Among 120 patients with reports available, including 33 patients previously tested, 15 (12%) were positive (1 BLM, 1 BRCA1, 3 BRCA2, 1 BRIP1, 1 CFTR, 1 CHEK2, 1 MUTYH, 1 PALB2, 1 PRSS1, 1 RAD50, 1 RET, and 2 TP53), 44 (37%) were negative, and 61 (51%) had an uncertain variant. The median time to STAT results (n = 50) was 8 days. The STAT results were available before surgery for 47 (98%) of the 48 STAT patients undergoing surgery.

CONCLUSIONS

New BC patients attending the MDBC demonstrated high rates of acceptance of GC and GT. The combination of GC and GT can offer timely information critical to patient risk assessment and treatment planning.

Transcriptome analysis provides critical answers to the "variants of uncertain significance" conundrum

While whole-genome and exome sequencing have transformed our collective understanding of genetics' role in disease pathogenesis, there are certain conditions and populations for whom DNA-level data fails to identify the underlying genetic etiology. Specifically, patients of non-White race and non-European ancestry are disproportionately affected by "variants of unknown/uncertain significance" (VUS), limiting the scope of precision medicine for minority patients and perpetuating health disparities. VUS often include deep intronic and splicing variants which are difficult to interpret from DNA data alone. RNA analysis can illuminate the consequences of VUS, thereby allowing for their reclassification as pathogenic versus benign. Here we review the critical role transcriptome analysis plays in clarifying VUS in both neoplastic and non-neoplastic diseases.

Provider discussion of genetic counseling among high-risk Spanish-preferring Latina breast cancer survivors

Among high-risk breast cancer (BC) survivors, genetic counseling (GC) and genetic testing (GT) may inform cascade testing and risk management. Compared to non-Hispanic White BC survivors, Spanish-preferring Latina BC survivors are less likely to report discussing GC with a healthcare provider. However, few studies have examined Latinas' experiences with GC/GT, particularly outside of the mainland USA. This study aimed to compare frequency of provider discussion of GC between Spanish-preferring Latina BC survivors living in Florida (FL) and Puerto Rico (PR). We conducted secondary data analysis of baseline assessments from a randomized pilot of an educational intervention for Spanish-preferring Latina BC survivors. Participants (N = 52) were GC/GT-naive, but met clinical criteria for GC/GT referral. Participants self-reported sociodemographic, clinical, and cultural variables, including previous provider discussion of GC. Descriptive statistics characterized frequency of GC discussion. Logistic regression examined the relationships between sociodemographic, clinical, and cultural characteristics and GC discussion. Only 31% of participants reported previous GC discussion. More participants from PR reported having GC discussions (43% vs. 21% in the mainland USA). In multivariable analyses, greater likelihood of GC discussion was associated with PR (vs. mainland USA) residence (odds ratio [OR] = 6.00, p = .03), older age at baseline (OR = 1.19, p = .04), and younger age at BC diagnosis (OR = 0.80, p = .03). Few high-risk Spanish-preferring Latina BC survivors in the mainland USA and PR had discussed GC with their providers. These results highlight a gap in the implementation of evidence-based genetics guidelines. Provider-directed interventions may be needed to increase uptake of GC/GT among Latina BC survivors.

Risk‐reducing mastectomy decisions among women with mutations in high‐ and moderate‐ penetrance breast cancer susceptibility genes

Background

Women harboring mutations in breast cancer susceptibility genes are at increased lifetime risk of developing breast cancer and are faced with decisions about risk management, including whether to undergo high‐risk screening or risk‐reducing mastectomy (RRM). National guidelines recommend BRCA1 or BRCA2 mutation carriers consider RRM, but that carriers of moderate penetrance mutations (e.g., ATM or CHEK2) should be managed based on family history. We aimed to investigate determinants of decision for RRM, and hypothesized that mutation status, age, family history, partner status, and breast cancer would impact RRM decision making.

Methods

We performed a retrospective study assessing RRM decisions for 279 women.

Results

Women with BRCA and moderate penetrance gene mutations, a personal history of breast cancer, or a first degree relative with a history of breast cancer were more likely to undergo RRM. Breast cancer status and age showed an interaction effect such that women with breast cancer were less likely to undergo RRM with increasing age.

Conclusion

Although national guidelines do not recommend RRM for moderate penetrance carriers, the rates of RRM for this population approached those for BRCA mutation carriers. Further insights are needed to better support RRM decision‐making in this population.

Trends in opioid use following balloon kyphoplasty or vertebroplasty for the treatment of vertebral compression fractures

This retrospective analysis of insurance claims evaluated real-world trends in prescription fills among patients treated with balloon kyphoplasty (N = 6,656) or vertebroplasty (N = 2,189) following diagnosis of vertebral compression fracture. Among those with evidence of opioid use, nearly half of patients discontinued or reduced prescription fills relative to pre-operative levels.

INTRODUCTION

Vertebral compression fractures (VCF) are associated with debilitating pain, spinal misalignment, increased mortality, and increased healthcare-resource utilization in elderly patients. This study evaluated the effect of balloon kyphoplasty (BKP) or vertebroplasty (VP) on post-procedure opioid prescription fills and payer costs in patients with VCF.

METHODS

This was a retrospective analysis of a large, nationally representative insurance-claims database. Clinical characteristics, opioid prescription patterns, and payer costs for subjects who underwent either BKP or VP to treat VCF were evaluated beginning 6 months prior to surgery through 7-month follow-up that included a 30-day, postoperative medication washout. Patient demographics, changes in opioid utilization, and payer costs were analyzed.

RESULTS

A total of 8,845 patients met eligibility criteria (75.3% BKP and 24.7% VP) with a mean of age 77 and 74% female. Among the 75% of patients who used opioids, 48.7% of patients discontinued opioid medication and 8.4% reduced prescription fills versus preoperative baseline. Patients who reduced or discontinued prescriptions exhibited a decrease in all-cause payer costs relative to pre-intervention levels, which was a significantly greater change relative to patients with no change, increase, or new start of opioids.

CONCLUSIONS

Interventional treatment for VCF was associated with decreased or discontinued opioid prescription fills and reduced payer costs in follow-up in a significant proportion of the study population. Reduction of opioid-based harms may represent a previously unrecognized benefit of vertebral augmentation for VCF, especially in this elderly and medically fragile population.

Development and pilot testing of a training for bilingual community education professionals about hereditary breast and ovarian cancer among Latinas: ÁRBOLES Familiares

Cancer health disparities remain a significant problem in the USA, compounded by lack of access to care, language barriers and systemic biases in health care. These disparities are particularly evident in areas such as genetics/genomics. For example, Latinas at high risk for hereditary breast and ovarian cancer (HBOC) have extremely low rates of genetic counseling/testing. Long-standing barriers and inequities in access to services such as genetic counseling and testing require innovative solutions. One solution can involve training community outreach and education professionals (CORE-Ps) to bridge the gap between underserved communities and genetic specialists. We sought to develop and pilot test a training program for English-Spanish bilingual CORE-Ps to reduce disparities in access to and uptake of genetic services among Latino populations. Guided by Adult Learning Theory and with input from multiple stakeholders, we developed ÁRBOLES Familiares (Family Trees), an in-person and online training program for bilingual CORE-Ps to facilitate identification, referral, and navigation of Latinas to genetic counseling/testing. We conducted a pilot test of 24 CORE-Ps recruited from across the United States and assessed knowledge, genetic literacy, and self-efficacy at baseline and follow-up. At follow-up, participants in the pilot with complete baseline and follow-up data (N = 15) demonstrated significant improvements in HBOC knowledge, genetic literacy, self-efficacy and reports of fewer barriers to identify/navigate Latinas (ps < .05). Qualitative assessment identified ways to improve the training curriculum. Pilot results suggest ÁRBOLES is a promising approach for training CORE-Ps to identify and refer high-risk Latinas to genetic services. Next steps involve further refinement of ÁRBOLES, development of an online toolkit, and adaptation for virtual delivery.

A Case Series of Multiple Primary Malignancies Among Patients With Advanced Melanoma

Multiple primary malignancies (MPM) are described as two or more primary tumors within the same individual. The impact of MPM on the tumor microenvironment among patients with melanoma is poorly understood. Here, we describe this unique group of patients who have both advanced melanoma and at least one other primary malignancy and report their survival outcomes. In this study, patients with advanced melanoma and a second primary malignancy were identified. Medical records were reviewed for cancer treatment history. Kaplan-Meier methods were used to derive survival curves and estimate overall survival (OS), and log-rank tests were used to compare OS. Among 11 MPM patients, the most common non-melanoma cancers were breast (n = 3) and thyroid (n = 3). Median OS was 153.5 months for all patients. Median OS for synchronous MPM (sMPM) and metachronous MPM (mMPM) were 83.1 and 196.7 months, respectively (p= 0.10). Median OS was not reached when melanoma was diagnosed first, and 153.5 months when diagnosed second (p= 0.45). For six patients receiving immunotherapy for melanoma, there was a 100% complete response rate. In conclusion, patients with melanoma are at risk of secondary malignancies, including breast and thyroid cancer. The timing of secondary malignancies may impact prognosis. Further study of the impact of immunotherapy on MPM is warranted.

Assessing somatic and germline variants in cancer patients

10601

Background: The increasing integration of somatic and germline testing into oncology practice allows physicians to target oncologic therapy and identify those with cancer predisposition. We explored the impact of a somatic assay (liquid biopsy, LB) on the identification of patients appropriate for germline genetic testing. Methods: We identified a cohort of diverse cancer patients with LB to assess for targetable somatic gene variants at LAC+USC Medical Center between 2016 and 2020 (n= 467). To enrich the cohort for variants that may reflect germline findings, we focused on the 46 patients (9.9%) who had at least one variant identified with a cell-free DNA (cfDNA) fraction of 25.00% or greater. Retrospective chart review extracted demographics and medical history with variables related to cancer history and treatment. LB variants were classified based on whether germline confirmation was indicated and the results of germline tests, when done, were reviewed. Results: Table summarizes the characteristics of the 46 patients identified to have at least one variant on LB in ≤ 25% of the cfDNA. The most frequently mutated genes on LB were TP53 (n=18, 39%), KRAS (n=11, 24%), APC (n=8, 17%), BRCA2 (n=7, 15%), PIK3CA (n=6, 13.0%), and BRCA1 (n=4, 9%). Seventeen patients (40%) were referred for genetic counseling and 13 (30%) underwent germline testing of whom 10 (77%) carried pathogenic variants (PV). All germline PV were concordant with LB variants identified. Four patients with PV BRCA2 on LB and confirmed to be germline, had lung or biliary tract diagnoses, which are not part of the typical BRCA-tumor spectrum. Thirty-three patients were not referred for genetic counseling, though 24 (72%) had LB-identified variants in cancer predisposition genes and 18 (54%) merited a genetics referral. Among patients with germline mutations, three (23%) had targeted therapy and two (15%) had preventive surgery to address second primary cancer risk. Among the 467 patients with LB results, there were an additional 13 patients (not included in the enriched group) known to have a cancer predisposition gene PV. Only two (15%) had findings on LB reports that suggested germline testing would be indicated. Conclusions: While the purpose of somatic testing is to identify targeted therapy, it can provide germline insight, especially for patients not typically referred for genetic assessment. Further education and guidance is needed to assure that this aspect of somatic testing is appreciated by oncology providers and acted upon.[Table: see text]

A pilot randomized trial of an educational intervention to increase genetic counseling and genetic testing among Latina breast cancer survivors

Latinas are less likely to participate in genetic counseling (GC) and genetic testing (GT) than non-Hispanic Whites. A multisite, randomized pilot study tested a culturally targeted educational intervention to increase uptake of GC/GT among Latina breast cancer (BC) survivors (N = 52). Participants were recruited in Tampa, FL and Ponce, PR and randomized to: (a) fact sheet about BC survivorship (control) or (b) a culturally targeted educational booklet about GC/GT (intervention). Participants in the intervention condition were also offered no-cost telephone GC followed by free GT with mail-based saliva sample collection. Participants self-reported hereditary breast and ovarian cancer (HBOC) knowledge and emotional distress at baseline and 1- and 3-month follow-ups. We used logistic regression to examine differences in GC/GT uptake by study arm (primary outcome) and repeated measures ANOVA to examine the effects of study arm and time on HBOC knowledge and emotional distress (secondary outcomes). Compared to the control arm, intervention participants were more likely to complete GC (ORIntervention  = 13.92, 95% CI = 3.06-63.25, p < .01) and GT (ORIntervention  = 12.93, 95% CI = 2.82-59.20, p < .01). Study site did not predict uptake of GC (p = .08) but Ponce participants were more likely to complete GT (ORPonce  = 4.53, 95% CI = 1.04-19.72, p = .04). ANOVAs demonstrated an increase in HBOC knowledge over time across both groups (F(2,88) = 12.24, p < .01, ηp2  = 0.22). We also found a significant interaction of study arm and time, such that intervention participants demonstrated a greater and sustained (to the 3-month follow-up) increase in knowledge than control participants (F(2,88) = 3.66, p = .03, ηp2  = 0.08). No other main or interaction effects were significant (all p's> .15). Study findings demonstrate the potential of our culturally targeted print intervention. Lessons learned from this multisite pilot study for enhancing GC/GT in Latinas include the need to attend to both access to GC/GT and individual factors such as attitudes and knowledge.

Abstract PO-049: Genetic cancer risk assessment (GCRA) increases perceived personal control in Latinas at risk for hereditary breast and ovarian cancer

Introduction: GCRA, which includes genetic counseling and testing, identifies individuals at hereditary cancer risk. Despite recognition of GCRA as standard-of- care, Latinas remain underrepresented in clinics and little is known about their experience. Our study examines the effect of an adapted motivational interviewing (AMI) telephone intervention on GCRA uptake. Perceived personal control (PPC) assesses cognitive, behavioral and decisional locus of control relative to the possibility of having a hereditary condition. Purpose: 1) Evaluate the effect of an AMI intervention on GCRA uptake 2) Explore baseline PPC and how it is affected by GCRA and AMI Procedures: English or Spanish speaking adult Latinas, who met NCCN criteria for BRCA testing were eligible and approached when scheduling their GCRA at two safety-net hospitals and one cancer center. Participants were randomized to an AMI intervention, time-and-attention control health habits (HH), or usual care (UC). The 9-item validated PPC instrument (scored 0-2, no PPC to full PPC) was administered in participants’ preferred language at baseline, pre- and post-GCRA. Results: Of the 478 Latinas who consented, 152 (32%) were randomized to both the AMI and UC arms, and the remaining 174 (36%) assigned to the HH arm. Spanish was the primary language for 76% (n=362). The majority had a history of cancer (79%, n=375) and most (64%, n=241) were undergoing treatment at the time of GCRA. There was no difference in the demographics of each arm (p&gt;0.22). There was no difference in GCRA uptake by arm with 79% (n=379) keeping their appointment.

Baseline PPC: PPC scores were not different between the arms for total PPC (AMI = 1.36, HH = 1.36, UC = 1.37; p = 0.67). Domain scores were: cognitive = 1.22, behavioral = 1.32 and decisional = 1.54. Post-GRCA PPC: PPC increased 12% for the cohort and in the arms, with no difference in the magnitude of increase between arms (p&gt;0.68). The greatest increase was observed in cognitive PPC (&gt;17%) across the cohort. In the AMI arm, total PPC increased 11% for those with cancer (p=0.043) and English speakers had an increase of 20% compared to 11% for Spanish speakers. Behavioral PPC increased by 14% in both the AMI and UC arms (p=0.004). Decisional PPC increased 8.9% in the AMI arm (p=0.026). Conclusions: PPC scores increased post-GCRA, with no between-arm differences, suggesting that the shared exposure to GCRA may increase PPC for Latinas. AMI did not impact GCRA uptake, though we did observe an increase in PPC scores in this arm for English speakers and those with cancer. Therefore, the addition of AMI to GCRA may be particularly effective in increasing PPC for some patients. The most significant increases in post-GCRA PPC were observed in cognitive PPC, likely reflecting the educational focus of GCRA but also supports a need for focus on approaches to enhance decisional and behavioral control. This is further supported by our finding that an increase in decisional control was only seen in the AMI arm. This merits further exploration and study.

Citation Format: Charité Ricker, Bita Nehoray, Guadalupe M. Carvajal, Kathleen R. Blazer, Sharon Sand, Kimlin Ashing, April Vang, Kai Wang, Nancy Feldman, Jeffrey N. Weitzel. Genetic cancer risk assessment (GCRA) increases perceived personal control in Latinas at risk for hereditary breast and ovarian cancer [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-049.

Inhibition of poly(ADP-ribose) polymerase induces synthetic lethality in BRIP1 deficient ovarian epithelial cells

OBJECTIVE

Pathogenic variations in the homologous recombination (HR) gene, BRCA1 interacting protein C-terminal helicase 1 (BRIP1) increase the risk for ovarian cancer. PARP inhibitors (PARPi) exert a synthetic lethal effect in BRCA-mutated ovarian cancers. Effective HR requires cooperation between BRCA1 and BRIP1; therefore, BRIP1-incompetancy may predict vulnerability to synthetic lethality. Here we investigated the response of ovarian epithelial cells with defective BRIP1 function to PARPi, and compared these cells to those lacking BRCA1 activity.

METHODS

We engineered Chinese Hamster ovarian (CHO) epithelial cells to express deficient BRIP1 or BRCA1, and exposed them to olaparib with or without carboplatin or cisplatin. We assessed cellular proliferation and survival; we calculated inhibitory concentrations and combination and reduction drug indices.

RESULTS

BRIP1 and BRCA1 inactivation impedes HR activity, decreases cellular proliferation and compromises DNA damage recovery. Platinum agent exposure impairs cellular survival. Olaparib exposure alone decreases cell viability in BRCA1-deficient cells, although has no effect on BRIP1-deficient cells. Combining carboplatin or cisplatin with olaparib synergistically attenuates cellular survival, consistent with synthetic lethality.

CONCLUSIONS

BRIP1-deficient ovarian epithelial cells exhibit defective HR, resulting in synthetic lethality when exposed to a platinum agent/PARPi combination. PARPi alone had no effect; this lack of effect may result from distinguishing molecular properties of BRIP1and/or consequences of genomic background. Our study identifies altered BRIP1 as a target for precision medicine-based therapies for ovarian cancers. This investigation supports consideration of the use of a platinum agent/PARPi combination in ovarian cancers depending upon genetic profile and genomic background.

BRCA1/2 mutations and risk-reducing bilateral salpingo-oophorectomy among Latinas: The UPTAKE study

Bilateral salpingo-oophorectomy (BSO) is a risk management approach with strong evidence of mortality reduction for women with germline mutations in the tumor suppressor genes BRCA1 and BRCA2 (BRCA1/2). Few studies to date have evaluated uptake of BSO in women from diverse racial and ethnic backgrounds who carry BRCA1/2 mutations. The objective of the UPTAKE study was to explore rates and predictors of risk-reducing BSO among Latinas affected and unaffected with breast cancer who had a deleterious BRCA1/2 mutation. We recruited 100 Latina women with deleterious BRCA1/2 mutations from community hospitals, academic health systems, community, and advocacy organizations. Women completed interviews in Spanish or English. We obtained copies of genetic test reports for participants who provided signed medical release. After performing threefold cross-validation LASSO for variable selection, we used multiple logistic regression to identify demographic and clinical predictors of BSO. Among 100 participants, 68 had undergone BSO at the time of interview. Of these 68, 35 were US-born (61% of all US-born participants) and 33 were not (77% of the non-US-born participants). Among Latinas with BRCA1/2 mutations, older age (p = 0.004), personal history of breast cancer (p = 0.003), higher income (p = 0.002), and not having a full-time job (p = 0.027) were identified as variables significantly associated with uptake of BSO. Results suggest a high rate of uptake of risk-reducing BSO among a sample of Latinas with BRCA1/2 mutations living in the US. We document factors associated with BSO uptake in a diverse sample of women. Relevant to genetic counseling, our findings identify possible targets for supporting Latinas' decision-making about BSO following receipt of a positive BRCA1/2 test.

Management of Male Breast Cancer: ASCO Guideline

PURPOSE

To develop recommendations concerning the management of male breast cancer.

METHODS

ASCO convened an Expert Panel to develop recommendations based on a systematic review and a formal consensus process.

RESULTS

Twenty-six descriptive reports or observational studies met eligibility criteria and formed the evidentiary basis for the recommendations.

RECOMMENDATIONS

Many of the management approaches used for men with breast cancer are like those used for women. Men with hormone receptor-positive breast cancer who are candidates for adjuvant endocrine therapy should be offered tamoxifen for an initial duration of five years; those with a contraindication to tamoxifen may be offered a gonadotropin-releasing hormone agonist/antagonist plus aromatase inhibitor. Men who have completed five years of tamoxifen, have tolerated therapy, and still have a high risk of recurrence may be offered an additional five years of therapy. Men with early-stage disease should not be treated with bone-modifying agents to prevent recurrence, but could still receive these agents to prevent or treat osteoporosis. Men with advanced or metastatic disease should be offered endocrine therapy as first-line therapy, except in cases of visceral crisis or rapidly progressive disease. Targeted systemic therapy may be used to treat advanced or metastatic cancer using the same indications and combinations offered to women. Ipsilateral annual mammogram should be offered to men with a history of breast cancer treated with lumpectomy regardless of genetic predisposition; contralateral annual mammogram may be offered to men with a history of breast cancer and a genetic predisposing mutation. Breast magnetic resonance imaging is not recommended routinely. Genetic counseling and germline genetic testing of cancer predisposition genes should be offered to all men with breast cancer.

Advancing precision medicine in clinical oncology: Whole exome paired tumor-normal DNA and RNA sequencing at a single-institution cancer center

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Background: Next generation sequencing (NGS) allows for reliable, comprehensive and cost-effective identification of clinically actionable genetic and genomic alterations. The increasing adoption of NGS in clinical oncology has increased our ability to identify germline alterations predisposing to cancer development as well as somatic changes enabling prescription of individualized cancer treatment and enhanced clinical trial participation. Here we summarize implementation of an NGS-based precision medicine initiative involving oncology patients from a single institution cancer center. Methods: IRB-approved NGS matched whole exome (WES) germline and solid tumor somatic tumor sequencing together with somatic tumor RNA sequencing (RNA-seq) were performed using germline DNA extracted from peripheral blood lymphocytes and nucleic acids for tumor DNA and RNA sequencing obtained from formalin-fixed, paraffin-embedded tumor specimens. Results of sequencing and analyses were presented to a multi-disciplinary tumor board to establish recommendations for management of germline pathogenic variation, therapeutic drug matching, clinical trials eligibility and molecularly informed patient prognosis. Results: A total of 1,005 patients completed sequencing. Germline and somatic WES exceeded 100X and 250X mean target coverage, respectively; somatic RNA-seq exceeded 200 million mean reads. Patients ranged in age from 17 to 90 years. The study cohort comprised comparable numbers of female (51%) and male (49%) patients. Ethnicities and races were broadly represented with 22% of participants identifying as Hispanic, 14% as Asian, 4% as Black, 55% as Non-Hispanic White and 5% as other. The most common solid tumor histological classification was colorectal (18%), followed by breast (16%), prostate (7%), head and neck (7%), sarcoma (7%), ovarian (5%), melanoma (4%) and lung (3%). Bioinformatic analyses and precision medicine tumor board review established that 12% of patients harbored a germline pathogenic variant and 43% carried clinically actionable genetic/genomic alterations; a majority of patients met molecular requirements for participation in a clinical trial. Conclusions: This study confirms the feasibility and utility of clinical NGS and precision medicine tumor board review in clinical oncology to identify germline genetic pathology, deliver personalized cancer therapeutics, increase clinical trial enrollment and clarify diagnosis and prognosis.

Pathogenic and likely pathogenic variants in PALB2, CHEK2, and other known breast cancer susceptibility genes among 1054 BRCA-negative Hispanics with breast cancer

BACKGROUND

Breast cancer (BC) is the most common cancer and related cause of mortality among Hispanics, yet susceptibility has been understudied. BRCA1 and BRCA2 (BRCA) mutations explain less than one-half of hereditary BC, and the proportion associated with other BC susceptibility genes is unknown.

METHODS

Germline DNA from 1054 BRCA-mutation-negative Hispanic women with hereditary BC (BC diagnosed at age <51 years, bilateral BC, breast and ovarian cancer, or BC diagnosed at ages 51-70 years with ≥2 first-degree or second-degree relatives who had BC diagnosed at age <70 years), 312 local controls, and 887 multiethnic cohort controls was sequenced and analyzed for 12 known and suspected, high-penetrance and moderate-penetrance cancer susceptibility genes (ataxia telangiectasia mutated [ATM], breast cancer 1 interacting protein C-terminal helicase 1 [BRIP1], cadherin 1 [CDH1], checkpoint kinase 2 [CHEK2], nibrin [NBN], neurofibromatosis type 1 [NF1], partner and localizer of BRCA2 [PALB2], phosphatase and tensin homolog [PTEN], RAD51 paralog 3 [RAD51C], RAD51D, serine/threonine kinase 11 [STK11], and TP53).

RESULTS

Forty-nine (4.6%) pathogenic or likely pathogenic variants (PVs) in 47 of 1054 participants (4.5%), including 21 truncating frameshift, 20 missense, 5 nonsense, and 4 splice variants, were identified in CHEK2 (n = 20), PALB2 (n = 18), ATM (n = 5), TP53 (n = 3), BRIP1 (n = 2), and CDH1 and NF1 (both n = 1) and none were identified in NBN, PTEN, STK11, RAD51C, or RAD51D. Nine participants carried the PALB2 c.2167_2168del PV (0.85%), and 14 carried the CHEK2 c.707T>C PV (1.32%).

CONCLUSIONS

Of 1054 BRCA-negative, high-risk Hispanic women, 4.5% carried a PV in a cancer susceptibility gene, increasing understanding of hereditary BC in this population. Recurrent PVs in PALB2 and CHEK2 represented 47% (23 of 49) of the total, suggesting a founder effect. Accurate classification of variants was enabled by carefully controlling for ancestry and the increased identification of at-risk Hispanics for screening and prevention.

Preventive surgery after multiplex genetic panel testing (MGPT)

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Background: Guidelines recommend consideration of prophylactic surgery for patients with a germline pathogenic variant in some cancer predisposition genes. We assessed surgery utilization in a prospective, multi-institutional cohort study of MGPT. Methods: 2000 patients had MGPT and completed questionnaires at 3, 6, and 12 months. Patients reported surgical utilization and indication (treatment or prevention). Surgery utilization was assessed according to cancer history and MGPT test results: Positive, pathogenic variant; VUS, variant of uncertain significance; Negative, benign variants. Results: Overall, 12.9% (198/1537) of patients reported surgery after MGPT (median follow-up 13 months). Only 31.3% (62/198) of patients specified that their surgery was preventive. Preventive surgery utilization was significantly higher among patients who tested positive (n=30, 14.9%) compared to those testing negative (n=20, 2.3%, p<0.001) or VUS (n=12, 2.2%, p<0.001). Preventive surgery was very low among patients testing negative or VUS who had no personal history of cancer in the relevant organ (Table). For example, mastectomy was not reported among any patients testing negative or VUS who had no personal history of breast cancer (Table). Conclusions: More than one year after MGPT, prophylactic surgery use was low among patients with VUS or negative results, especially among those with no personal history of cancer at the relevant site. Surgery utilization. [Table: see text]

Multicenter Prospective Cohort Study of the Diagnostic Yield and Patient Experience of Multiplex Gene Panel Testing For Hereditary Cancer Risk

Purpose

Multiplex gene panel testing (MGPT) allows for the simultaneous analysis of germline cancer susceptibility genes. This study describes the diagnostic yield and patient experiences of MGPT in diverse populations.

Patients and Methods

This multicenter, prospective cohort study enrolled participants from three cancer genetics clinics—University of Southern California Norris Comprehensive Cancer Center, Los Angeles County and University of Southern California Medical Center, and Stanford Cancer Institute—who met testing guidelines or had a 2.5% or greater probability of a pathogenic variant (N = 2,000). All patients underwent 25- or 28-gene MGPT and results were compared with differential genetic diagnoses generated by pretest expert clinical assessment. Post-test surveys on distress, uncertainty, and positive experiences were administered at 3 months (69% response rate) and 1 year (57% response rate).

Results

Of 2,000 participants, 81% were female, 41% were Hispanic, 26% were Spanish speaking only, and 30% completed high school or less education. A total of 242 participants (12%) carried one or more pathogenic variant (positive), 689 (34%) carried one or more variant of uncertain significance (VUS), and 1,069 (53%) carried no pathogenic variants or VUS (negative). More than one third of pathogenic variants (34%) were not included in the differential diagnosis. After testing, few patients (4%) had prophylactic surgery, most (92%) never regretted testing, and most (80%) wanted to know all results, even those of uncertain significance. Positive patients were twice as likely as negative/VUS patients (83% v 41%; P < .001) to encourage their relatives to be tested.

Conclusion

In a racially/ethnically and socioeconomically diverse cohort, MGPT increased diagnostic yield. More than one third of identified pathogenic variants were not clinically anticipated. Patient regret and prophylactic surgery use were low, and patients appropriately encouraged relatives to be tested for clinically relevant results.

Nivolumab use for BRCA gene mutation carriers with recurrent epithelial ovarian cancer: A case series

Tumors deficient in DNA mismatch repair are known to display increased susceptibility to immune checkpoint inhibitors due to accumulation of DNA damage and increased neoantigen load. This suggests that deficiency in the BRCA-related DNA repair mechanism may also be a surrogate marker for immunotherapy response. The aim of this study was to examine the efficacy of the immune checkpoint inhibitor, nivolumab, in women with BRCA gene mutations and recurrent müllerian cancer. This retrospective case series followed six BRCA carriers who received nivolumab monotherapy (3.0 mg/kg, intravenous, day 1 and 15, every 4 weeks) as salvage therapy for recurrent epithelial ovarian (n = 5) and fallopian tubal (n = 1) cancers. Toxicity, treatment response, and survival were examined. Median age was 57 (range 51–64). BRCA1 and 2 mutations were equally distributed. All had high-grade serous histology, and all but one had advanced-stage disease at initial diagnosis. The majority had platinum-resistant disease (n = 4). All received salvage therapy prior to nivolumab therapy (median 3 lines), including PARP inhibitors (n = 3). The median number of nivolumab treatment cycles was 9, including 2 women receiving 18 cycles. Three women developed nivolumab-related toxicities, most commonly grade 2 hypothyroidism (n = 2). Median follow-up time was 13.4 months, and there were 3 complete responses, 1 partial response, and 2 patients with progressive disease. Objective response rate was 67% (4 out of 6). In conclusion, our study suggests that nivolumab monotherapy is well-tolerated and may be an effective salvage therapy for BRCA mutation carriers with recurrent epithelial ovarian, fallopian tubal, and primary peritoneal cancers.

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Examined nivolumab treatment for recurrent ovarian cancer with BRCA mutations

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Median number of treatment cycles was 9; one third received 18 cycles.

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3 (50%) out of 6 cases had a complete response and 1 (17%) had a partial response.

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Objective response rate was 67% (4 out of 6).

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Nivolumab may be effective in BRCA-related recurrent ovarian cancer.

Abstract P6-10-05: UPTAKE study - Uptake of preventive surgeries among Latinas with BRCA1/2 mutations

Introduction: Germline testing for BRCA1/2 genes provides an opportunity to reduce mortality and morbidity by adopting appropriate risk reduction and screening options, in particular with risk-reducing bilateral salpingo-oophorectomy (BSO).There is a paucity of data on Latinas and prophylactic measures among BRCA1/2 carriers.Existing studies are limited either by the small number of Latinas, or limited to a specific geographic location.Factors related to decision making have also not been evaluated.

Methods: The UPTAKE study is an observational study of Latinas with germline BRCA1/2 mutations.Subjects were recruited nationally and, by telephone interviews, reported uptake of prophylactic surgeries (BSO, bilateral mastectomy in unaffected women, and contralateral mastectomy in carriers with breast cancer (BC)). Women with ovarian cancer were ineligible. All women had to have been informed that they carried a deleterious BRCA1/2 mutation at least 1 year prior to completing the interview. The objectives of this study are: 1)to examine the rate of uptake of prophylactic surgeries; 2)identify acculturation and attitudinal factors related to decisions made and 3)examine relationships between primary language, receipt of genetic counseling (GC) and in which language it was provided and uptake of prophylactic surgeries. We plan to enroll 100 participants.

Results: As of 6/11/2017, 86 telephone interviews have been conducted. We anticipate that all 100 interviews will be completed by July 2017. 51.2% (44/86) of participants completed the interview in Spanish. Our population was diverse in terms of country of origin: 50.0% (43/86) were born in the US, 22.1% (19/86) in Mexico, 11.6% (10/86) in Puerto Rico, 4.6% (4/86) in El Salvador, 3.5% (3/86) in Ecuador and 8.1% (7/86) in other countries of Latin America. 30% (26/86) of the participants reported an annual household income inferior to $50.000. Only 26.7% (23/86) of women reported having a graduate degree. Approximately one quarter of participants were unemployed at the time of study participation (26.7%, 23/86). 34.9% (30/86) were unaffected and 62.8% (54/86) were affected with BC. 73.3% (63/86) of participants reported having received formal GC, of which only 28.6% (18/63) was conducted in Spanish. 66.3% (57/86) of women opted to undergo BSO and 58.1% (50/86) underwent prophylactic mastectomy. Being born outside the US and currently working were associated with higher uptake of BSO. Multivariate analysis will be performed once all interviews have been completed.

Conclusions: To our knowledge this is the largest study that evaluates uptake of prophylactic measures in Latinas known to be BRCA1/2 carriers. Our study included a heterogeneous group of participants in terms of country of origin, income and level of education including English knowledge. It was conducted across various academic and community centers in the country. The uptake of prophylactic surgeries among Latinas with germline BRCA mutations seems to be slightly lower than what has been reported in non-Hispanic whites (71-74%) but higher than in African Americans (32-50%). Results and factors associated with decision making will be updated once the total number of participants is enrolled.

Citation Format: Lynce F, Serrano A, Friedman S, Nahleh Z, Dutil J, Campos C, Ricker C, Rodriguez P, Duron Y, Isaacs C, Graves K. UPTAKE study - Uptake of preventive surgeries among Latinas with BRCA1/2 mutations [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-10-05.

Unexpected CDH1 Mutations Identified on Multigene Panels Pose Clinical Management Challenges

Purpose

Mutations in the CDH1 gene confer up to an 80% lifetime risk of diffuse gastric cancer and up to a 60% lifetime risk of lobular breast cancer. Testing for CDH1 mutations is recommended for individuals who meet the International Gastric Cancer Linkage Consortium (IGCLC) guidelines. However, the interpretation of unexpected CDH1 mutations identified in patients who do not meet IGCLC criteria or do not have phenotypes suggestive of hereditary diffuse gastric cancer is clinically challenging. This study aims to describe phenotypes of CDH1 mutation carriers identified through multigene panel testing (MGPT) and to offer informed recommendations for medical management.

Patients and Methods

This cross-sectional prevalence study included all patients who underwent MGPT between March 2012 and September 2014 from a commercial laboratory (n = 26,936) and an academic medical center cancer genetics clinic (n = 318) to estimate CDH1 mutation prevalence and associated clinical phenotypes. CDH1 mutation carriers were classified as IGCLC positive (met criteria), IGCLC partial phenotype, and IGCLC negative.

Results

In the laboratory cohort, 16 (0.06%) of 26,936 patients were identified as having a pathogenic CDH1 mutation. In the clinic cohort, four (1.26%) of 318 had a pathogenic CDH1 mutation. Overall, 65% of mutation carriers did not meet the revised testing criteria published in 2015. All three CDH1 mutation carriers who had risk-reducing gastrectomy had pathologic evidence of diffuse gastric cancer despite not having met IGCLC criteria.

Conclusion

The majority of CDH1 mutations identified on MGPT are unexpected and found in individuals who do not fit the accepted diagnostic testing criteria. These test results alter the medical management of CDH1-positive patients and families and provide opportunities for early detection and risk reduction.

Spectrum of mismatch repair gene mutations and clinical presentation of Hispanic individuals with Lynch syndrome

Lynch syndrome (LS), the most common hereditary colorectal cancer syndrome, is caused by mismatch repair (MMR) gene mutations. However, data about MMR mutations in Hispanics are limited. This study aims to describe the spectrum of MMR mutations in Hispanics with LS and explore ancestral origins. This case series involved an IRB-approved retrospective chart review of self-identified Hispanic patients (n = 397) seen for genetic cancer risk assessment at four collaborating academic institutions in California, Texas, and Puerto Rico who were evaluated by MMR genotyping and/or tumor analysis. A literature review was conducted for all mutations identified. Of those who underwent clinical genetic testing (n = 176), 71 had MMR gene mutations. Nine mutations were observed more than once. One third (3/9) of recurrent mutations and two additional mutations (seen only once) were previously reported in Spain, confirming the influence of Spanish ancestry on MMR mutations in Hispanic populations. The recurrent mutations identified (n = 9) included both previously reported mutations as well as unique mutations not in the literature. This is the largest report of Hispanic MMR mutations in North America; however, a larger sample and haplotype analyses are needed to better understand recurrent MMR mutations in Hispanic populations.

Abstract A50: Differences in perceived personal control among Latina women undergoing genetic cancer risk assessment for hereditary breast and ovarian cancer

Introduction: Genetic cancer risk assessment (GCRA) is a growing subspecialty that identifies individuals at risk for hereditary predisposition to cancer. Despite recognition of GCRA as a standard-of-care service, there are significant disparities in access to GCRA among at-risk underserved Latina women. Therefore, little is known about the emotional and decisional experience of Latinas undergoing GCRA. Previous studies have looked at the concept of perceived personal control (PPC) as an outcome variable of GCRA, measuring an individual's feelings of control related to the possibility of having a hereditary condition. This study examined PPC among patients participating in a randomized controlled study examining the effect of an adapted motivational interview (AMI) pre-GCRA telephone intervention to promote uptake of GCRA by underserved Latinas.

Purpose: To evaluate the influence of the AMI intervention and GCRA on PPC at baseline, immediately pre- and post-GCRA among English and Spanish-speaking Latinas at risk for hereditary breast and ovarian cancer.

Method: Eligible participants were adult women who self-identified as Latina, understood English and/or Spanish, and met NCCN criteria for BRCA1 and BRCA2 testing. Participants were randomized to a motivational interview intervention, time and attention control, or usual care. A validated 9-item instrument to assess three dimensions of perceived personal control (behavioral, decisional, and cognitive control) over a genetic problem and the counseling process was translated to Spanish and verbally administered in the patients' preferred language at baseline (prior to randomization) and immediately pre and post-GCRA. A higher PPC score indicates an increased sense of PPC. The three dimensions of PPC encompass a total PPC score.

Results: Of the 411 participants, 323 (78.6%) were affected by breast cancer and 88 (21.4%) were unaffected at time of enrollment. Two-hundred and eighty-two (68.6%) were Spanish-speakers and 129 (31.4%) spoke English. While not significant, total PPC scores increased from baseline to post-GCRA and from pre-GCRA to post-GCRA, but decreased from baseline to pre-GCRA for all participants (the affected and unaffected individuals, including English and Spanish-speakers). Unaffected women had significantly higher total PPC scores than women affected with cancer (p=0.001). Unaffected patients had higher cognitive PPC scores at baseline (p=0.008), pre-GCRA (p=0.019), and post-GCRA (p=0.001) compared to the affected participants at all three time points. Unaffected individuals scored higher in behavioral PPC at post-GCRA than the affected participants (p=0.012). The unaffected individuals scored higher in decisional PPC at post-GCRA compared to the affected individuals (p=0.005). There were no significant differences in PPC scores between English and Spanish-speaking participants or between study arms.

Conclusion: Cognitive, decisional, behavioral, and total PPC scores were highest at post-GCRA among all groups (unaffected and affected individuals, and English and Spanish-speakers). Unaffected individuals had higher cognitive PPC scores at all three times points compared to affected participants. Interestingly, the affected participants scored higher in behavioral PPC at baseline, but scored lower post-GCRA compared to those who are unaffected. This suggests that after receiving information during GCRA, the unaffected individuals may believe that they have more control over their health and opportunities for cancer prevention. Decrease in total PPC from baseline to pre-GCRA may be associated with pre-counseling anxiety. More investigation into the three dimensions of PPC should be conducted in order to better understand their distinctions and relationship to GCRA.

Citation Format: Tanya A. Chavez, Bita Nehoray, Charité Ricker, Kathleen R. Blazer, Sharon Sand, Kimlin T. Ashing, Jaime Cordova, Gwen Uman, Kai Yang, Nancy Feldman, Jeffrey N. Weitzel. Differences in perceived personal control among Latina women undergoing genetic cancer risk assessment for hereditary breast and ovarian cancer. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr A50.

Abstract P2-09-07: The patient experience in a prospective trial of multiplex gene panel testing for cancer risk

Background: Multiplex gene sequencing panels (MGP) are increasingly used for assessment of hereditary breast cancer risk. Compared to testing for BRCA1 and BRCA2 (BRCA1/2) only, testing more genes increases the likelihood of identifying a deleterious mutation (DM) and/or a variant of uncertain significance (VUS), which might cause distress, uncertainty or regret about testing. Little is known about the patient experience of MGP testing.

Methods: We conducted a prospective study of MGP testing, using a panel of 25 genes: APC, ATM, BARD1, BMPR1A, BRCA1, BRCA2, BRIP1, CDH1, CDK4, CDKN2A, CHEK2, EPCAM, MLH1, MSH2, MSH6, MUTYH, NBN, PALB2, PMS2, PTEN, RAD51C, RAD51D, SMAD4, STK11, and TP53. Participants were enrolled at three medical centers and were eligible if they met standard genetic testing guidelines or if they had a ≥2.5% probability of a DM in any gene on the panel, as calculated by predictive models (e.g. IBIS, Penn II, MMRPro). Participants were surveyed about their experiences with MGP testing including distress and uncertainty at baseline (before test results disclosure) and three months later. The 25-item Multidimensional Impact of Cancer Risk Assessment (MICRA) scale measured distress, uncertainty and positive experiences at three months after testing. We present a planned interim analysis after enrolling 500 of 2000 total participants.

Results: Of 500 participants, 332 (66%) were referred for suspicion of hereditary breast/ovarian cancer syndrome. Of these 332, 97% were female, 79% were white, 43% were Hispanic and 33% were Spanish-speaking only; for 25%, high school was their highest level of education. A total of 48% had breast cancer, 5% had ovarian cancer, and 7% had another cancer: 11% had a DM and 35% had VUS in one or more genes. At study entry most participants thought about cancer rarely or not at all (69%, 95% confidence interval (CI) 58%-77%), and few (7%, CI 3%-14%) had thoughts of cancer that affected their daily lives; results were unchanged three months later, after genetic results disclosure (Chi-squared test, p-value &gt;0.1). MICRA scores at three months were low for distress (mean score 2 out of a possible 30) and uncertainty (mean score 7 out of 45), and high for positive testing experiences (mean score 9 out of 15). Most (82%, CI 72%-88%) participants wanted to know all of their MGP results even if the clinical relevance was not fully understood, and most (87%, CI 79%-93%) never regretted learning their MGP results.

Conclusions: Among diverse participants of a prospective, multi-center MGP testing trial, cancer- and genetic testing-related distress were low at entry and remained low three months later. These results provide no evidence for an increase in distress or uncertainty after MGP. Longer-term follow-up in a larger cohort is underway.

Citation Format: Kurian AW, Idos G, McDonnell K, Ricker C, Sturgeon D, Culver J, Lowstuter K, Hartman A-R, Allen B, Rowe-Teeter C, Kingham KE, Koff RB, Lebensohn A, Chun NM, Petrovchich IM, Mills MA, Hong C, Ladabaum U, Ford JM, Gruber SB. The patient experience in a prospective trial of multiplex gene panel testing for cancer risk. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-09-07.

Abstract A36: Exploring the climate, barriers, and possible approaches to implementing genetic cancer risk assessment in Latin America: A roundtable discussion

Genetic cancer risk assessment (GCRA) is an interdisciplinary medical subspecialty practice that employs a growing arsenal of genetic and genomic tools to identify individuals and families with increased risk for cancer, often prior to the onset of disease, when early detection or prevention strategies are most effective. Access to GCRA is a standard of care in most developed countries, but is not available in most of Latin America. In March of 2014, City of Hope in Duarte, CA, conducted a roundtable discussion forum with 16 Latin American physicians representing Brazil, Colombia, Mexico, Peru, and Puerto Rico. The purpose of the roundtable was to explore the current state of GCRA services, including policy, resources, and barriers, in the respective Latin American countries. Thirteen participants attended in-person and 3 via web conference. The session was moderated by a team comprised of 4 bilingual cancer genetics clinicians. Participants were prompted with open-ended discussion questions eliciting perceived needs and the current status of GCRA services in their country, barriers to GCRA practice, and possible approaches to address access barriers. The session was largely conducted in Spanish, recorded, and transcribed. The transcript was coded and thematically analyzed. Preliminary analysis identified barriers to GCRA implementation, including: (1) limited patient and provider knowledge about GCRA, (2) lack of insurance coverage and high patient out-of-pocket costs for GCRA testing, (3) long turnaround time for genetic test results, (4) absence of readily available provider training or expertise, and (5) lack of institutional infrastructure or policy to support the development of GCRA programs. Participants emphasized the importance of collecting evidence to support the efficacy of GCRA in their own populations as an essential step toward building GCRA services in their countries. The findings also point to the need for a multi-level approach that addresses the need for education and training and cost-effective genetic testing, as well as the creation of an evidence-based foundation for the development of policy, infrastructure and resources to implement and sustain GCRA services in Latin America.

Citation Format: Tanya Chavez, Bita Nehoray, Alexandra Obregon-Tito, Charité Ricker, Ilana Solomon, Mariana Niell-Swiller, Christina Ryback, Julio E. Abugattas, Yasser Sullcahuaman, María F. Noriega, Ana I. Orduz, Jorge M. Melo, Ana Chaves, Lenny Gallardo, Cynthia Villarreal, Robin Shaw, Rosa M. Álvarez, Eunice F. Morales, Alicia M. Cock-Rada, Azucena Del Toro, Pamela Mora, Marcia Cruz, María E. Fernández, Kathleen R. Blazer, Jeffrey N. Weitzel. Exploring the climate, barriers, and possible approaches to implementing genetic cancer risk assessment in Latin America: A roundtable discussion. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr A36.

Abstract 2761: Evaluation of the BOADICEA model for predicting BRCA1 and BRCA2 mutation carrier probabilities in high-risk US Hispanic and Mexican families: A report from the Clinical Cancer Genetics Community Research Network

Background: BRCA1 and BRCA2 (BRCA) mutation prediction models are low cost tools that enable clinicians to target individuals with a higher probability to carry mutations in the BRCA genes. Most of the data used to construct these models were derived from a predominantly non-Hispanic White population. The predictive accuracy of these models in diverse populations is unclear. The Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) was developed using population-based families with multiple affected individuals that were primarily from the UK. The purpose of this study was to investigate and compare the accuracy of BOADICEA for prediction of BRCA mutation status among US Hispanics and a cohort of Mexicans in Guadalajara and Mexico City.

Methods: Hispanic patients undergoing genetic cancer risk assessment (GCRA) were enrolled in an IRB-approved prospective registry from sites within the Clinical Cancer Genetics Community Research Network (CCGCRN), comprised of the City of Hope and 47 collaborating sites representing primarily community-based oncogenetic practices across the US and Latin America, including two cancer institutes in Mexico (University of Guadalajara; Instituto Nacional de Cancerología, Mexico City). Pedigrees were created in Progeny, exported to text files, and then uploaded for probablity calculations according to BOADICEA version 3 guidelines. Accuracy was assessed using an observed versus expected and an area under the receiver operating characteristic (ROC) curve analysis.

Results: Overall, BOADICEA performed better in US Hispanics (area under the curve [AUC] = 0.75) for predicting a BRCA mutation than in the Mexican cohort (AUC = 0.64; p-value = 0.0015). Although BRCA mutations were documented in 238 of 1,247 (19.1%) US Hispanics and 23 of 234 (9.8%) Mexicans, BOADICEA predicted a mean mutation probability of 10.3% and 5.6%, respectively.

Summary: Though generally the best performing model, BOADICEA's ability to predict BRCA mutations has been investigated in previous studies with different populations with varying results. The lower performance of BOADICEA in the Mexican cohort could be a result of the limitations in pedigree data. It's possible that families don't share information about cancer due to cultural norms or fear of stigmitation. It is also possible that the model assumptions about population mutation frequency are inaccurate. The results of this study indicate the need to document the clinical reliability of probability models when evaluating high risk US Hispanics and patients in Mexico.

Citation Format: Jessica Clague, Cynthia Villarreal-Garza, Adrian Daneri Navarro, Alexandra J. Obregon-Tito, Sharon Sand, Tanya A. Chavez, Bita Nehoray, Lacolle Robinson, Lenny Gallardo, Azucena Del Toro, Rosa Alvarez, Kathleen R. Blazer, Blu Yanez, Charité Ricker, Gary W. Unzeitig, Kai Yang, Jeffrey N. Weitzel. Evaluation of the BOADICEA model for predicting BRCA1 and BRCA2 mutation carrier probabilities in high-risk US Hispanic and Mexican families: A report from the Clinical Cancer Genetics Community Research Network. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2761. doi:10.1158/1538-7445.AM2015-2761

Abstract P4-01-11: Clinical Findings and Outcomes from MRI Staging of Breast Cancer in a Diverse Population

Background: Staging breast MRI can detect occult breast cancers in 1–10% of newly diagnosed patients. The performance of MRI, impact of patient factors, and resulting surgical management in underserved and diverse populations has not been well studied.

Methods We performed a retrospective analysis of consecutive patients with newly diagnosed in situ or invasive breast cancer (2006–2011) who had a preoperative staging MRI seen at our Centers that cares for an underserved and minority population. IRB approval was obtained to extract demographic and clinicopathological data, imaging studies and surgical treatment. Non-index lesions (NIL) were defined as those in breast or axillary nodes not known to be malignant or presenting with clinical, mammographic or ultrasound findings, in a different quadrant and given an MRI BIRADS score of 4 or 5. Occult cancers (OC) were those lesions found by biopsy or surgery to be invasive or in situ cancer. Logistic regression was used to examine the association between the probability of a NIL or OC and patients characteristics. Statistical computation was performed using STATA.

Results: Among 678 patients, 144 (21%) had a total of 171 NIL identified by MRI; 67 (9.8%) were ipsilateral, 44 (6.5%) contralateral and 24(3.5%)axillary nodes. 57 patients (8.4%) had a total of 62 OCs detected −34 (5%) ipsilateral, 8(1.2%) contralateral, and 9(1.3%) axillary nodes of which 49 (7.2%) were invasive and 8 (1.2%) in situ. 40% of patients with NILs were confirmed as OCs.

Prevalence and type of BRCA mutations in Hispanics undergoing genetic cancer risk assessment in the southwestern United States: a report from the Clinical Cancer Genetics Community Research Network

PURPOSE

To determine the prevalence and type of BRCA1 and BRCA2 (BRCA) mutations among Hispanics in the Southwestern United States and their potential impact on genetic cancer risk assessment (GCRA).

PATIENTS AND METHODS

Hispanics (n = 746) with a personal or family history of breast and/or ovarian cancer were enrolled in an institutional review board-approved registry and received GCRA and BRCA testing within a consortium of 14 clinics. Population-based Hispanic breast cancer cases (n = 492) enrolled in the Northern California Breast Cancer Family Registry, negative by sequencing for BRCA mutations, were analyzed for the presence of the BRCA1 ex9-12del large rearrangement.

RESULTS

Deleterious BRCA mutations were detected in 189 (25%) of 746 familial clinic patients (124 BRCA1, 65 BRCA2); 21 (11%) of 189 were large rearrangement mutations, of which 62% (13 of 21) were BRCA1 ex9-12del. Nine recurrent mutations accounted for 53% of the total. Among these, BRCA1 ex9-12del seems to be a Mexican founder mutation and represents 10% to 12% of all BRCA1 mutations in clinic- and population-based cohorts in the United States.

CONCLUSION

BRCA mutations were prevalent in the largest study of Hispanic breast and/or ovarian cancer families in the United States to date, and a significant proportion were large rearrangement mutations. The high frequency of large rearrangement mutations warrants screening in every case. We document the first Mexican founder mutation (BRCA1 ex9-12del), which, along with other recurrent mutations, suggests the potential for a cost-effective panel approach to ancestry-informed GCRA.

Closing the loop: an interactive action-research conference format for delivering updated medical information while eliciting Latina patient/family experiences and psychosocial needs post-genetic cancer risk assessment

A patient/family-centered conference was conducted at an underserved community hospital to address Latinas' post-genetic cancer risk assessment (GCRA) medical information and psychosocial support needs, and determine the utility of the action research format. Latinas seen for GCRA were recruited to a half-day conference conducted in Spanish. Content was partly determined from follow-up survey feedback. Written surveys, interactive discussions, and Audience Response System (ARS) queries facilitated the participant-healthcare professional action research process. Analyses included descriptive statistics and thematic analysis. The 71 attendees (41 patients and 27 relatives/friends) were primarily non-US born Spanish-speaking females, mean age 43 years. Among patients, 73 % had a breast cancer history; 85 % had BRCA testing (49 % BRCA+). Nearly all (96 %) attendees completed the conference surveys and ARS queries; ≥48 % participated in interactive discussions. Most (95 %) agreed that the format met their personal interests and expectations and provided useful information and resources. Gaps/challenges identified in the GCRA process included pre-consult anxiety, uncertainty about reason for referral and expected outcomes, and psychosocial needs post-GCRA, such as absorbing and disseminating risk information to relatives and concurrently coping with a recent cancer diagnosis. The combined action research and educational conference format was innovative and effective for responding to continued patient information needs and addressing an important data gap about support needs of Latina patients and family members following genetic cancer risk assessment. Findings informed GCRA process improvements and provide a basis for theory-driven cancer control research.

P3-14-21: Neoadjuvant Therapy Response, Subtype and BRCA Status in an Underserved Population

Background

Preoperative (neoadjuvant) chemotherapy is typically used for larger operable breast cancer cases, and the degree of pathological response correlates with long term outcome. Therapeutic response also depends on biological and molecular subtype and is increasingly studied in the research setting to identify prognostic biomarkers and potential therapeutic targets. Little is known about the interactions of neoadjuvant response with biomarker subtypes and genetic predisposition in underserved and minority populations.

Methods: IRB approval was obtained to capture demographic, clinicopathological and genetic testing data on patients diagnosed with invasive breast cancer and treated with preoperative chemotherapy and definitive surgery between 2005 and 2010 at Los Angeles County Medical Center, which serves a primarily Hispanic and indigent population. Treatment followed NCCN guidelines with the exception that not all patients with HER2+ disease received trastuzumab. Genetic counseling and testing has been available at this center since 2007. Pathological complete response (pCR) was defined as no residual invasive disease in breast or nodes. Chi-square or Fisher's Exact test was used to examine associations between pCR and clinical factors, and logistic regression analyses were applied to assess each variable's contribution to pCR.

Results: Among 104 patients, of whom 79% were Hispanic, the overall pCR rate was 27%. Significantly higher pCR rates were seen in age ≥50, clinical N0, HER2+, triple negative, and lumpectomy cases. No differences in pCR rate was seen in Hispanics vs. others, Grade III vs. I and II or in the 9 BRCA mutations carriers among 45 tested compared to no mutation or those not tested. Of the 43 patients with HER2+ disease, the pCR rate was higher in the 32 patients who received trastuzumab (pCR 50.0 vs. 27.3%). Subset pCR rates and odds ratios (OR) of achieving pCR are shown below:

Abstract P2-02-04: MRI Findings and Outcomes in an Underserved Breast Cancer Population Screened with BRCA Testing

Background: Patients with breast cancer and a familial risk and/or BRCA 1 or 2 mutations are at high risk of contralateral breast cancer and ipsilateral recurrence. While MRI screening is recommended for patients with BRCA mutations, and MRI staging for breast cancer is being increasingly used, the outcomes of such testing are not well described, especially in underserved populations. At Los Angeles County Hospital (LAC) for the last 3 years, we have enacted a program of genetic counseling and testing based standard guidelines as well as MRI evaluation of all patients newly diagnosed with breast cancer. LAC serves a population that includes a high number of indigent patients, primarily Hispanic (60%) and Asian (15%). Methods: We undertook a retrospective evaluation of all patients seen at LAC from March 2008 to March 2010 who underwent genetic counseling/testing and MRI as preoperative assessment for histologically documented breast cancer or followup after cancer treatment. IRB approval was obtained to extract data for this analysis. Demographic information along with clinical presentation, MRI and mammography results, additional imaging results, biopsy and surgical procedure and corresponding pathology data were obtained through the review of electronic medical records and clinic charts.

Results: A total of 90 patients had both genetic testing and MRI reports available. The median age of all tested patients was 41 years. Ethnicity was 78% Hispanic, 9% Asian, 7% African American, 2% Caucasian and 4% other. BRCA mutation was seen in 20 cases (22%), 12 BRCA-1, 8 BRCA-2, 4 variants of unknown significance, and 66 had no mutation. Breast mass or other symptoms were the mode of detection in 89% of the overall cohort, and 81% in mutation carriers. The index lesion was visible on MRI in 78% and by mammogram in 82% of all patients. Ipsilateral MRI showed 7 abnormal non-index findings in 6 patients (7%); 6 of 7 lesions biopsied showed cancer. In the contralateral breast, 7 abnormalities were noted on MRI, but only 5 were amenable to biopsy as 2 could not be visualized by any means on follow up, and 1 showed cancer. Interestingly, only one of the 13 patients with abnormal findings carried a mutation (BRCA-1) and this patient did not have cancer on contralateral lesion biopsy. Mastectomy was performed in 91% and 78% of patients with and without mutation. Conclusions: Screening, counseling and testing for BRCA mutations is feasible in an underserved population, with a 22% mutation identification rate. MRI detected 5 non-index ipsilateral cancers and one contralateral cancer among 90 patients, with none of the detected cancers among the 20 mutation carriers. While MRI staging may be effective at detecting additional cancers in this underserved and high familial risk population, this appears to be independent of BRCA status.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-02-04.

Honoramos A Todas Nuestras Madres Con El Don Del Conocimiento: A Conference To Learn the Needs of Latina Patients and Families Seen for Breast Cancer Risk Assessment

Background: Long-term follow-up surveys of Spanish-speaking Latina patients at increased risk for hereditary breast cancer who completed genetic cancer risk assessment (GCRA) in our underserved clinics revealed a need for ongoing education and support. Consequently, we invited patients back for a half-day educational conference, employing mixed methods research to better understand their medical and social/cultural issues and needs.Aims: The conference aims were to: 1) share medical advances in GCRA and cancer screening and prevention recommendations and resources and 2) explore GCRA-related experiences and needs, and access to risk-appropriate care.Methods: Invitees were Latina patients with personal and/or family history of breast cancer who completed GCRA between 2001-2009 and their family members. The conference, conducted entirely in Spanish, was held at the regional county medical facility where our underserved clinic is conducted. Educational information was delivered by podium-presentations, expert and patient panel discussions and interactive sessions and community resource booth exhibits. Mixed methods research (surveys and Audio Response System [ARS] mediated interaction and discussion) was used to explore GRCA experiences and access to care.Results: The 71 primarily Spanish speaking (96%) participants ranged in age from 18 to 71 years (mean age, 44), were female (93%), had children (78%), and had at least completed high school (71%). Of the 41 patient-participant, 78% were accompanied by at least one family member and/or friend. Thirty (73%) had a personal history of breast cancer; 4 also had ovarian cancer. Of the 35 tested, 20 (57%) were BRCA positive. Nearly all participants (96%) completed the voluntary survey and post-conference evaluation. On average, 87% responded to eight ARS questions related to the GCRA process and access to care. The majority of patient-participant (71%) understood why they were referred for GCRA, 15% did not, and 13% were uncertain. Eighty percent understood their cancer risk; however 20% expressed a need for more risk information. Although 83% understood cancer screening recommendations, 17% were unsure and requested more information. Interestingly, only 5% reported lack of access to care. More than 75% found the GCRA process stressful and desired more support and preparedness for sharing information with relatives. All responders (96%) reported that the conference met their expectations, valued the resources provided, and suggested allocating more time for questions in a future conference.Conclusion: The interactive conference format was highly rated and effective in providing Latina breast cancer patients and family members with ongoing education and support following GCRA, and provided important information to guide improvement in the risk assessment process.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3073.

If We Build It … Will They Come? – Establishing a Cancer Genetics Services Clinic for an Underserved Predominantly Latina Cohort

BACKGROUND

Cancer genetic counseling and testing is a standard of care option for appropriate families and can identify individuals at increased risk prior to diagnosis, when prevention or detection strategies are most effective. Despite documented efficacy of cancer risk reduction in high-risk individuals, underserved and minority individuals have a disproportionate cancer burden and limited access to genetic counseling.

METHODS

A needs assessment survey documented gaps in knowledge and interest in prevention. Satellite clinics were established at two indigent healthcare systems. Cancer genetics CME lectures were conducted and referral guidelines disseminated to clinicians who referred patients for counseling.

RESULTS

An increase in clinician knowledge was demonstrated post-CME and reflected by quality referrals. Eighty-eight percent of patients kept their appointments. In the predominantly Latina(6) (n=77) clinic population, 71.4% were affected with cancer, and 17 mutation positive families were identified. Preliminary data shows a positive impact on patients' motivation and behavior. The majority has expressed satisfaction and reduction in anxiety.

CONCLUSIONS

This study demonstrates feasibility and acceptability of cancer genetics services in this population, suggesting the potential to reduce cancer morbidity in underserved, high-risk families.

Prevalence of BRCA mutations and founder effect in high-risk Hispanic families

Approximately 12% of the U.S. population is Hispanic, with the majority residing in urban centers such as Los Angeles. The prevalence of BRCA mutations among high-risk Hispanic families is unknown.

METHODS

One hundred and ten unrelated probands of Hispanic origin, with a personal or family history of breast and/or ovarian cancer, presented for genetic cancer risk assessment, were enrolled in an Institutional Review Board-approved registry and underwent BRCA testing. Haplotype analyses were done if BRCA mutations were observed in two or more unrelated probands.

RESULTS

Mean age at diagnosis was 37 years (range = 23-59) for the 89 (81%) probands with invasive breast cancer. Overall, 34 (30.9%) had deleterious mutations (25 in BRCA1, 9 in BRCA2), 25 (22.7%) had one or more unclassified variants, and 51 (46.4%) had negative results. The mean pretest mutation probability using the Couch model, Myriad model, and BRCAPro was 19.6% (range = 4-77%). The combined average mutation probability was 32.8% for carriers, 15.5% for noncarriers, and 12.9% for variant carriers (P < 0.0001). The most common deleterious mutation was 185delAG (4 of 34, 11.8%). The Hispanic 185delAG carrier families share the same haplotype from D17s1320 through BRCA1, as do two reference Ashkenazi Jewish families. Haplotype analyses of additional recurrent BRCA1 mutations [IVS5+1G>A (n=2),S955X (n = 3), R1443X (n = 3), and 2552delC (n = 2)] also suggest founder effects, with four of six mutations seen almost exclusively in families with Latin American/Caribbean or Spanish ancestry.

CONCLUSION

This is the largest study to date of high-risk Hispanic families in the United States. Six recurrent mutations accounted for 47% (16 of 34) of the deleterious mutations in this cohort. The BRCA1185delAG mutation was prevalent (3.6%) in this clinic-based cohort of predominantly Mexican descent, and shared the Ashkenazi Jewish founder haplotype.

Properties of cyclopean motion perception

This study investigated the ability of human observers to discriminate the direction of laterally-moving cyclopean stimuli, in order to assess some of the properties of stereoscopic mechanisms that mediate the perception of cyclopean motion (motion existing at levels of binocular integration). The stimuli were moving grating patterns created from dynamic random-dot stereograms. Experiment 1 showed that duration thresholds for discrimination decrease with velocity; they are not governed by temporal frequency nor a constant spatial displacement. Experiment 2 revealed that discrimination thresholds increase with disparity magnitude, for both the crossed and uncrossed disparity directions equally. Experiment 3 showed that the rate of temporal variation at and above which direction discrimination fails (cyclopean upper limit of temporal resolution) is 8 Hz. Our results indicate that a mechanism for motion perception exists at binocular-integration levels of the visual system, which supports a model of motion perception that posits the existence of first-order and second-order processes.