Contralateral prophylactic mastectomy rate and predictive factors among patients with breast cancer who underwent multigene panel testing for hereditary cancer

Although multigene panel testing is increasingly common in patients with cancer, the relationship between its use among breast cancer patients with non-BRCA mutations or variants of uncertain significance (VUS) and disease management decisions has not been well described. This study evaluated the rate and predictive factors of CPM patients who underwent multigene panel testing. Three hundred and fourteen patients with breast cancer who underwent multigene panel testing between 2014 and 2017 were included in the analysis. Of the 314 patients, 70 elected CPM. Election of CPM by gene status was as follows: BRCA carriers (42.3%), non-BRCA carriers (30.1%), and VUS (10.6%). CPM election rates did not differ between non-BRCA carriers and BRCA carriers (P = 0.6205). Among non-BRCA carriers, negative hormone receptor status was associated with CPM (P = 0.0115). For those with a VUS, hormone receptor status was not associated with CPM (P = 0.1879). Although the rate of CPM between BRCA carriers and non-BRCA carriers was not significantly different, the predictors of CPM were different in each group. Our analyses shed the light on the increasing use of CPM among patients who are non-BRCA carriers as well those with a VUS. Our study elucidates the differing predictive factors of CPM election among BRCA carriers, non-BRCA carries, and those with a VUS. Our findings reveal the need for providers to be cognizant that non-BRCA genes and VUS drive women to elect CPM despite the lack of data for contralateral breast cancer risk associated with these genes.

BRCA mutations in women with inflammatory breast cancer

BACKGROUND

Inflammatory breast cancer (IBC) often affects women at a relatively young age. To the authors' knowledge, the rate of BRCA variants among patients with IBC is not known. To determine the association between BRCA status and IBC, the authors evaluated its rate and compared the clinicopathologic characteristics of patients with IBC with those of patients with other breast cancers (non-IBC).

METHODS

Patients who presented at the study institution's cancer genetics program and who underwent BRCA genetic testing were included in the current study. The authors compared clinicopathologic data between patients with IBC and those with non-IBC using propensity score matching to identify predictors.

RESULTS

A total of 1789 patients who underwent BRCA genetic testing (1684 with non-IBC and 105 with IBC) were included. BRCA pathogenic variants were found in 27.3% of patients with non-IBC and 18.1% of patients with IBC (P = .0384). After propensity score matching, there were no significant differences noted between patients with IBC and those with non-IBC, including the rate of BRCA pathogenic variants (P = .5485). However, a subgroup analysis of the 479 patients with BRCA pathogenic variants demonstrated that patients with IBC (19 patients) were diagnosed at significantly younger ages compared with patients with non-IBC (P = .0244).

CONCLUSIONS

There was no clear association observed between BRCA pathogenic variants and IBC. However, among patients who tested positive for BRCA pathogenic variants, those with IBC were younger at the time of diagnosis compared with those with non-IBC breast cancers. These results confirm that genetic testing is important for patients with IBC who meet the current clinical criteria for genetic testing in breast cancer. Cancer 2018;124:466-74. © 2017 American Cancer Society.

Breast cancer phenotype in patients with hereditary gene mutations other than BRCA1 and BRCA2

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Background: Use of multi-gene panel (MGP) testing for hereditary breast cancer (BC) has increased significantly. Unlike in case of TNBC diagnosed before age 60 and ordering BRCA testing; for MGP testing, healthcare providers depend on personal and/or family history of cancer as tumor phenotype and on patient characteristics for non-BRCA hereditary BC genes which are not well described. Therefore, we planned to evaluate tumor phenotype of BCs associated with hereditary gene mutations other than BRCA 1 and BRCA2. Methods: Consecutive patients with invasive BC who are in a prospective cohort study and who underwent MGP testing based on published criteria as clinically indicated were included in the study. All patients’ breast pathology slides were reviewed by breast pathologists at our institution. For statistical analysis: Patients’ demographic and clinical characteristics were summarized using descriptive statistics such as frequency distribution, mean (± s.d.) and median (range). SAS version 9.4 and S-Plus version 8.04 were used to carry out the computations for all analyses. Institutional IRB approval was obtained. Results: Between 2013 and 2017, 1607 patients underwent MGP testing and 347 were found to be positive for a pathogenic variant. For the study purposes we included only patients with invasive breast cancer (N = 146). Median age was 45.1 yrs (Range: 25-78). Genetics testing results were as follows: BRCA1: 38 (26%), BRCA2: 37 (25%), CHEK2 15 (10%), PALB2: 12 (8%) , ATM: 12 (8%), TP53: 9 (6%), CDH1 : 5 (3%), PTEN: 3 (2%), BRIP1: 3 (2%), and 12 patients (8%) positive for other genes (CDKN2A, MUTYH, PMS2, APC, BARD1, MLH1, NBN, RAD51C, and SDHD). Tumor phenotype by gene mutation in shown in table 1. Conclusions: Several hereditary BC genes are associated with ER positive BC which could have implications for chemoprevention, while others associated with ER neg/TNBC that could have therapeutic implications. These findings and implications need to be further studied in larger cohorts. [Table: see text]

Abstract P2-07-09: CPM rate among individuals with breast cancer who underwent multiplex gene testing for hereditary cancer: Single institution experience

Background: Availability of multiplex gene (MPG) testing for hereditary cancer has led to increase use of panel testing versus single gene testing for hereditary cancer. These panels include high, but also moderate penetrance genes. For some of these genes, associated cancer risk and risk management guidelines do not exist. Furthermore there is a high rate of variant of unknown significant (VUS) findings in non-BRCA genes. Currently, in the absence or minimal available data, health care providers and patients are faced with important risk management decisions, especially regarding preventive surgeries, such as prophylactic mastectomy. Currently, there is no data regarding prophylactic mastectomy rate among patients with breast cancer who underwent (MPG) testing. Therefore, our aim was to evaluate the rate of contralateral prophylactic mastectomy (CPM) in a cohort of individuals who underwent multiplex gene testing. Methods: Eight hundred thirty five patients with breast cancer who underwent MPG testing between the years 2013 and 2016 were identified using Institutional Clinical Cancer Genetics Database. Patients with pathogenic, likely pathogenic variants or who had a VUS were included in the analysis. Results: Of 835 patients with a diagnosis of breast cancer; 105 (13%) had a pathogenic or likely pathogenic mutation: 29 (28%) BRCA1, 26 (25%) BRCA2, 11 (11%) ATM, 2 (2%) BARD1, 3 (3%) BRIP, 9 (9%) CHEK2, 1 (1%) MSH2, 1 (1%) NBN, 5 (5%) PALB2, 4 (4%) PTEN, 1 (1%) RAD51C, 5 (5%) TP53, 4 (4%) CDH1, 2 (2%) MUTYH, 1 (1%) PMS2, 1 (1%) APC (1). A total of 102 (12%) VUS were found. Average age of diagnosis was 44 (Range 21-81). CPM rate was 32% (n=66) for the total cohort. Twenty nine % (n=19) of patients with non-BRCA mutations, 24.2% (n=16) with VUS and 46% (n=31) with BRCA mutations opted for CPM. Conclusion: Overall 32% of breast cancer patients with germline mutations or VUS opt for CPM at our institution. The rate for CPM in non- BRCA mutations carriers is high despite no available data regarding contralateral breast cancer risk and benefit of CPM. This finding should be validated in larger cohorts, including identification of reasons behind decision for CPM in these cohorts.

Citation Format: Elsayegh N, Gutierrez Barrera AM, Kuerer HM, Hernandez ND, Litton JK, Arun BK. CPM rate among individuals with breast cancer who underwent multiplex gene testing for hereditary cancer: Single institution experience [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-07-09.

Evaluation of BRCAPRO Risk Assessment Model in Patients with Ductal Carcinoma In situ Who Underwent Clinical BRCA Genetic Testing

The authors retrospectively aimed to determine which of the following three scenarios, related to DCIS entry into BRCAPRO, predicted BRCA mutation status more accurately: (1) DCIS as an invasive breast cancer (IBC) entered using the actual age of diagnosis, (2) DCIS as IBC entered with 10 years added to the actual age of diagnosis, and (3) DCIS entered as no cancer. Of the 85 DCIS patients included in the study, 19% (n = 16) tested positive for a BRCA mutation, and 81% (n = 69) tested negative. DCIS patients who tested positive for a BRCA mutation had a higher BRCAPRO risk estimation (34.61%) than patients who tested negative (11.4%) when DCIS was entered at the actual age of diagnosis. When DCIS was entered with 10 years added to the actual age at diagnosis, the BRCAPRO estimate was still higher amongst BRCA positive patients (25.4%) than BRCA negative patients (7.1%). When DCIS was entered as no cancer, the BRCAPRO estimate remained higher among BRCA positive patients (2.56%) than BRCA negative patents (1.98%). In terms of accuracy of BRCA positivity, there was no statistically significant difference between DCIS at age at diagnosis, DCIS at 10 years later than age at diagnosis, and DCIS entered as no cancer (AUC = 0.77, 0.784, 0.75, respectively: p = 0.60). Our results indicate that regardless of entry approach into BRCAPRO, there were no significant differences in predicting BRCA mutation in patients with DCIS.

Predictors that Influence Election of Contralateral Prophylactic Mastectomy among Women with Ductal Carcinoma in Situ who are BRCA-Negative

The authors retrospectively examined the contralateral prophylactic mastectomy (CPM) rate among 100 women with ductal carcinoma in situ who are BRCA negative. Of 100 women with ductal carcinoma in situ, 31 elected contralateral prophylactic mastectomy (CPM). Factors associated with increased likelihood of undergoing contralateral prophylactic mastectomy (CPM) among this cohort were: family history of ovarian cancer, marital status, reconstruction, mastectomy of the affected breast, and tamoxifen use.

Predictors that influence contralateral prophylactic mastectomy election among women with ductal carcinoma in situ who tested negative for a BRCA mutation

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Background: Patients with ductal carcinoma in situ (DCIS) are at increased risk for developing contralateral breast cancer (CBC). Consequently, more women with DCIS are electing to undergo contralateral prophylactic mastectomy (CPM). We previously reported a 27% CPM rate among patients with DCIS who were evaluated for BRCA genetic testing (positive, negative, not tested). In this specific cohort, we further evaluated factors associated with CPM in patients with DCIS who tested negative for a BRCA mutation. Specifically, we aimed to identify differences within BRCA-negative patients who underwent CPM and those who did not. Methods: This retrospective study from a prospective registry included 100 women with DCIS referred for genetic counseling between 2003 and 2011. Patient characteristics included: age, marital and educational status, tumor markers, nuclear grade, family history of breast cancer (BC) and ovarian cancer (OC), race, Ashkenazi Jewish ancestry, and BRCA results. Univariate and multivariate logistic regression analyses were used to determine predictive factors associated with CPM election. Results: Of 100 BRCA-negative patients, 31 (31%) underwent CPM. Univariate analysis revealed patients who had a first-degree relative with OC were more likely to elect CPM that those who did not (p = 0.0278). Patients who had a family history of OC (53.3%) were more likely to choose CPM than those with no family history (p = 0.0425). Married patients were more likely to elect CPM than those who were not married (p = 0.0235). In multivariate analysis, married patients were more likely to elect CPM than those who were not married (OR = 4.367; 95% CI, 1.198-15.924; p = 0.0255). Conclusions: The CPM rate among patients with DCIS who tested negative for a BRCA mutation is high. Factors associated with increased rate of CPM among this group include a family history of OC and being married. Further studies are needed to evaluate patients' perceptions of CBC risk and their role in the likelihood of CPM choice.

Predictors that influence contralateral prophylactic mastectomy election among women with ductal carcinoma in situ who were evaluated for BRCA genetic testing

BACKGROUND

Patients with ductal carcinoma in situ (DCIS) are at increased risk for developing contralateral breast cancer (CBC). Consequently, more women with DCIS are electing to undergo contralateral prophylactic mastectomy (CPM). We evaluated factors associated with CPM in patients with DCIS who underwent genetic counseling for BRCA testing.

METHODS

This retrospective study involved 165 women with DCIS referred for genetic counseling between 2003 and 2011. Patient characteristics were age, marital and educational status, tumor markers, nuclear grade, family history of breast cancer (BC) and ovarian cancer (OC), race, Ashkenazi Jewish ancestry, and BRCA results. Univariate and multivariate logistic regression analyses were used to determine predictive factors associated with CPM election.

RESULTS

Of 165 patients, 44 (27 %) underwent CPM. Patients <45 years of age were more likely to elect CPM (p = 0.0098). A BRCA+ mutation was found in 17 patients (10.3 %), and BRCA+ women were more likely to elect CPM than BRCA or untested women (p = 0.0001). Patients who had a family history of OC (57.7 %) were more likely to choose CPM than those with no family history (p = 0.0004). Younger age, BRCA+, and an OC family history remained significant in the multivariate model (p < 0.008).

CONCLUSION

The CPM rate among patients with DCIS who undergo genetic counseling is high. Factors associated with increased likelihood of CPM among this group were age, BRCA+, and a family history of OC. Further studies are needed to evaluate patients' perceptions of CBC risk and their role in the likelihood of CPM choice.

Abstract P5-13-03: Factors associated with prophylactic mastectomy among BRCA-positive patients with no personal history of breast cancer

Background: The rate of prophylactic mastectomy (PM) has recently increased1. A deleterious mutation in the BRCA1 or BRCA 2 genes is among the major reasons why patients pursue PM 2, 3. Women with BRCA1 or BRCA2 gene mutations have up to an 87% risk to develop an invasive breast cancer (BC), and up to 45% risk for ovarian cancer (OC)2, 3. Most studies evaluating predictors of PM in BRCA mutation carriers are performed among women with breast cancer; however, accurate predictors for PM among unaffected BRCA mutation carriers are less defined. In a single institution study we aimed to evaluate predictors of PM among BRCA carriers with no personal history of breast cancer.

Method: One hundred seventy seven women with no personal history of BC, who tested positive for a BRCA1 or BRCA 2 germline mutation, were included in the study. Patients’ characteristics were obtained from a prospectively maintained research database under an IRB approved protocol at UT MD Anderson Cancer Center. Univariate analyses using chi-square and logistic regression analysis were used to determine predictive factors associated with PM. The patient characteristics examined included age, martial and educational status, bilateral salphingo-oophorectomy (BSO), family history of 1st and 2nd degree relatives with breast (BC) and ovarian cancer (OC), race, and BRCA genetic test result.

Results: Out of the 177 BRCA1 and BRCA 2 positive patients, 51 (29%) elected for PM. The average age for the cohort was 44 years (range 23-91). The majority were Caucasian (81%), and married (72%) with a college degree (64%). One hundred sixty-four (92%) patients had 1st and 2nd degree relatives with BC, 93 (53%) had 1st and 2nd degree relatives with OC, and 85 (48%) had undergone BSO. A logistic regression model was run to identify factors associated with undergoing PM, including family history of OC, family history of BC, BSO and age. Patients with a family history of OC were 2.5 times more likely than those without to have had a PM (p = 0.0125), and patients who had a BSO were 0.137 times less likely to have had a PM (p &lt;.0001). Only 12 patients did not have a family history of BC and none of those patients had a PM, so an Odds Ratio could not be calculated. However, it was determined through the Fisher's exact test that patients with a family history of BC were more likely to undergo a PM (p = 0.0198).

Conclusion: The rate of PM in our cohort was slightly lower than expected. Factors associated with PM included a family history of BC and OC. Interestingly, having had a BSO was associated with lower likelihood of undergoing PM (menopausal status will be further evaluated); possibly due to the knowledge that BSO reduces breast cancer risk.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-13-03.

Predictors of contralateral prophylactic mastectomy among patients with ductal carcinoma in situ (DCIS) who underwent evaluation for BRCA genetic testing

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Background: Patients with DCIS are at increased risk for developing contralateral breast cancer (CBC). Therefore, an increasing number of women with DCIS are electing for contralateral prophylactic mastectomy (CPM). In a previous study involving 2072 women with DCIS, 13.5% chose CPM. In this study, we aimed to evaluate factors associated with CPM in patients with DCIS who underwent genetic counseling for BRCA. Methods: 165 women with pure DCIS, who underwent genetic counseling, were included in the study. Patients’ characteristics were obtained from a prospectively maintained research database at UT M.D. Anderson Cancer Center. Univariate and multivaraite logistic regression analysis were used to determine predictive factors associated with CPM. Patients’ characteristics included age, marital and educational status, tumor markers, nuclear grade, family history with breast (BC) and ovarian cancer (OC), race, Ashkenazi Jewish ancestry, and BRCA genetic test results. Results: Out of 165 patients, 17(10.3%) were found to have a BRCA deleterious mutation. 44(26.7%) underwent CPM. Younger patients (median ≤ 45 yr) were more likely to elect for CPM than older patients (p= 0.0098). Patients who tested positive for a BRCA mutation were more likely to elect for CPM than those who tested negative or were not tested (p= 0.0001). Patients who had a family history of OC (15 (57.7%) were more likely to choose CPM than those who did not (p= 0.0004). These three factors remained significant in the multivariate model (p <0.008). Marital and educational status, tumor markers, nuclear grade, and family history of breast cancer were not significant predictors of CPM. Conclusions: The rate of CPM in patients with DCIS is high. Factors associated with increased likelihood of undergoing CPM include family history of OC, age, and BRCA positivity. Further studies are needed to evaluate patients perception of CBC risk, and if this may play a role in the high number of CPM.

Comparison of BRCA1/2-positive and -negative women diagnosed with metachronous breast and ovarian cancers

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Background: After a primary breast cancer (BC) or ovarian cancer (OC) diagnosis, women have a risk to develop a second primary cancer, significantly more so in women with a BRCA gene mutation. The objective was to evaluate characteristics of BRCA positive and negative women diagnosed with metachronous BC and OC. Methods: Women with metachronous BC and OC were identified at the University of Texas MD Anderson Cancer Center. BRCA test results, age at diagnosis of both BC and OC, first degree relatives (FDR) with BC and/or OC, total relatives affected, and histopathologic tumor features were obtained from a prospectively maintained research database. Univariate and logistical regression analyses were performed. Results: A total of 64 women with metachronous primary cancers underwent BRCA genetic testing. Of the 45 BRCA positive women, 36 (80%) were diagnosed with BC (mean 40 years) prior to OC and 9 (20%) were diagnosed with OC first (mean 47 years). Of the 19 BRCA negative women, 10 (53%) were diagnosed with BC first (mean 63 years), and 9 (47%) diagnosed with OC first (mean 48 years). Women diagnosed with BC first were more likely to be BRCA positive than women diagnosed with OC first (p=0.03). Patients with a FDR with BC were more likely BRCA positive than women without family history (p=0.0062). Patients with PR negative BR (p=0.0199) or triple negative (TN) BC (p=0.0139) were more likely to test BRCA positive. High grade ovarian carcinomas approached significance (p=0.053) in BRCA positive when compared to BRCA negative cohort. Ethnicity, total number of affected relatives with BC or OC, ER status, Her2 status, and nuclear grade were not statistically significant between the two groups. Conclusions: Women with OC preceding their BC with lack of family history of BC and OC are significantly less likely to test BRCA positive. BC is often the sentinel cancer in women with a BRCA mutation compared to BRCA negative women with metachronous BC and OC. This should be considered during the risk assessment to more accurately estimate the chance of identifying a BRCA mutation in women with metachronous BC and OC.

P2-13-04: Testing Women with Invasive Lobular Breast Cancer for BRCA Mutations

Background: Infiltrating lobular carcinoma (ILC) is the second most common type of invasive breast cancer behind infiltrating ductal carcinoma (IDC). ILC makes up approximately eight percent of all invasive lesions. In addition, the mixed ductal and lobular carcinoma histology makes up approximately seven percent of all invasive diagnoses.

There are several biologic differences that are demonstrated by ILC compared to other common pathologies. They are more frequently bilateral and multicentric. They tend to be seen in women slightly older than the average age of diagnosis and are usually ER positive. It is also known that individuals with a genetic predisposition have an increased risk to develop breast cancers. Women with a mutation in their CDH1 gene have up to a 39% chance to develop ILC. The majority of hereditary breast cancer is caused by germ line mutations in the BRCA1 and BRCA2 genes. Women with a mutation in their BRCA1 or BRCA2 gene have up to an 87% risk to develop an invasive breast cancer, however, the presence of ILC in this population has not been well defined. Therefore, the aim of this study is to evaluate the rate of germline BRCA mutations in a cohort of patients both with pure ILC, as well as mixed ILC/IDC.

Methods: A retrospective chart review revealed one hundred and sixty nine women with ILC and mixed ILC/IDC who underwent genetic testing for mutations in the BRCA1 and BRCA2 genes through the Clinical Cancer Genetics Program at M. D. Anderson Cancer Center. Women are referred for genetic testing using referral guidelines based on the NCCN guidelines, this usually involves a personal history of early onset breast cancer and/or a family history of breast and/or ovarian cancer.

Results: Out of the 169 patients, 19 (11.24%) were found to have a germline mutation in their BRCA1 or BRCA2 gene. A significant majority (73.7%) of these patients were BRCA2 positive. Five women tested for a variant of uncertain significance. The average age of diagnosis for the cohort was 55.6 years (range 30–87); while the average age of diagnosis for a positive patient was 49.4 years (range 30–72). Of the 62 women with pure ILC, 5 (8.06%) were positive for a BRCA gene mutation. Historically, out of all the patients with breast cancer referred and tested through the Clinical Cancer Genetics Program, approximately 15% test positive, and research shows that in the general population, 7–10% of breast cancer patients will test positive.

Conclusions: while the positivity rates between the cohorts are not statistically significant, we have shown that patients with a BRCA mutation can develop ILC in addition to the more commonly seen IDC. We suggest that patients continue to be referred for genetic counseling according to the NCCN guidelines, regardless of the pathology of their tumor.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-13-04.

P4-10-06: Evaluation of BRCAPro Risk Assessment Model in Patients with Ductal Carcinoma In Situ

Background: The BRCAPRo model is used to predict a patient's likelihood to possess a BRCA1 or BRCA2 gene mutation based upon personal and family history. Ductal carcinoma in situ (DCIS) is considered a non-invasive condition which can progress to an invasive breast cancer if left untreated. Currently, DCIS is not specifically accounted for in the BRCAPro model, thereby causing DCIS to be weighted in the same manner as an invasive breast cancer diagnosis. Historically, a diagnosis of DCIS has been entered as having developed into an invasive breast cancer ten years later. However, there are no standard guidelines of how DCIS should be entered. We sought to determine if there were any differences in how DCIS was treated in the BRCAPro model to predict the more effective method in calculating the BRCAPro. Methods: Women with pure DCIS, who were referred for genetic counseling and underwent genetic testing, were included in the study. The likelihood of carrying a BRCA mutation was calculated using the BRCAPRO model (Version 5.1). Patient characteristics which were entered into the BRCAPro model include: tumor markers (estrogen receptor-ER and progesterone receptor-PR), history of oophorectomy prior to diagnosis, family history of 1st and 2nd degree relatives with breast and ovarian cancer, race and Ashkenazi Jewish ancestry. Each patient's BRCAPro risk estimate was calculated and compared by entering DCIS at the presenting age of diagnosis and by adding 10 years to the age of diagnosis. Descriptive statistics and a student's t-test were used to compare BRCAPro estimates between the two groups. Results: Ninety-five patients with pure DCIS underwent genetic counseling and testing. The average age of DCIS diagnosis was 45 years (range 26–65). Of the 95 DCIS patients included in the study 21% (n=20) tested positive for a BRCA gene mutation (8 BRCA1 and 12 BRCA2), 77% (n=74) test negative and 0.01% (n=1) had a variant of uncertain significance. Overall, DCIS patients who tested positive for a BRCA mutation had a higher BRCAPro (40%) than patients who tested negative (12%) when presenting age of diagnosis was assessed. When 10 years was added, the BRCAPro estimate was still higher amongst BRCA positive patients (28%) than BRCA negative patients (8%). The mean BRCAPro probability when DCIS was entered at presenting age of diagnosis was 18% (0.1−95.4) versus 12% (0.1−89.9) when calculated 10 years later. Conclusion: In our cohort there was no significant difference in BRCAPro probability whether DCIS was entered at the presenting age of diagnosis or 10 years later (p=0.1). However, future studies are needed to determine the most effective method to incorporate DCIS into the BRCAPro model in order to determine those individuals who may or may not be at increase risk to possess a BRCA gene mutation.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-10-06.

Identifying genomic rearrangements in BRCA1 and BRCA2 in high-risk individuals for hereditary breast and ovarian cancer

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Background: Germline mutations in the BRCA1 and BRCA2 genes are responsible for the majority of hereditary breast and ovarian cancer (HBOC). Comprehensive gene sequencing detects ~87% of BRCA mutations, and large genomic rearrangement testing (BART) accounts for ~3%. Criteria have been established to capture individuals who most likely have a BART mutation, however, recent data shows that some individuals have BART mutations and do not meet the criteria. We conducted a single-institution study to evaluate the sufficiency of BART criteria to determine if new criteria are warranted.

Methods: During 2006-2008, 172 individuals underwent BRCA sequencing and BART at M. D. Anderson Cancer Center. A retrospective, IRB-approved chart review of a prospectively maintained database was conducted to determine BART criteria eligibility, personal/family history of breast and ovarian cancer and tumor characteristics. Univariate and multivariate analysis was performed to test the significance of each variable in relation to BRCA1/BRCA2 positivity.

Results: Of 172 individuals, 12/34 (35%) had BRCA1 BART mutations, and 7/11 (64%) had BRCA2 BART mutations. Of the 19 individuals who tested positive for BART mutations, only 8 (42%) met BART criteria and 11 (58%) did not and proceeded with BART for various reasons (family history, insurance covered, and patient request). Individuals who were BRCA1 positive (sequencing or BART) were more likely to have ER/PR negative breast cancer (p<0.0001) and a personal (p=0.0215)/family history of ovarian cancer (p=0.0001) compared to non-carriers and individuals who had no family history Individuals who were BRCA1 sequencing positive were more likely to meet BART criteria than BRCA1 BART positive (p=0.0151) individuals.

Conclusions: Given that no significant differences in family history/tumor characteristics between individuals who have sequencing and BART mutations were identified, and a majority of individuals who were BART positive do not meet BART criteria, it appears that these criteria may be insufficient. BART testing should be considered for all individuals who undergo BRCA sequencing; however, large scale collaboration studies should be conducted.

Predictive factors for BRCA1/BRCA2 mutations in women with ductal carcinoma in situ

BACKGROUND

It is unclear whether women with ductal carcinoma in situ (DCIS), like their counterparts with invasive breast cancer, warrant genetic risk assessment and testing on the basis of high-risk variables. The authors of this report identified predictive factors for mutations in the breast cancer-susceptibility genes BRCA1 and BRCA2 in women who were diagnosed with DCIS.

METHODS

One hundred eighteen women with DCIS who were referred for genetic counseling and underwent genetic testing for BRCA1/BRCA2 mutations between 2003 and 2010 were included in the study. Logistic regression models were fit to determine the associations between potential predictive factors and BRCA status.

RESULTS

Of 118 high-risk women with DCIS, 27% (n = 32) tested positive for BRCA1/BRCA2 mutations. Of those, 10% (n = 12) and 17% (n = 20) had BRCA1 and BRCA2 mutations, respectively. Age, race, and tumor characteristics did not differ between BRCA noncarriers and carriers. In a multivariate logistic model, ≥2 relatives with ovarian cancer (OC) (odds ratio [OR], 8.81; 95% confidence interval [CI], 1.38-56.29; P = .034), and a score ≥10% according to the BRCAPRO mathematical model for calculating the probability that a particular family member carries a germline BRCA mutation (OR, 6.37; 95% CI, 2.23-18.22; P = .0005) remained as independent significant predictors for a BRCA mutation. Fifty-seven percent of mutation carriers but only 25% of noncarriers underwent prophylactic mastectomy(P = .0037). This difference remained significant for patients aged ≤40 years (P = .025).

CONCLUSIONS

Women who had DCIS and a family history of OC or who had BRCAPRO scores ≥10% had a high rate of BRCA positivity regardless of age at diagnosis. These findings suggest that high-risk patients with DCIS are appropriate candidates for genetic testing for BRCA mutations in the presence of predictive factors even if they do not have invasive breast cancer.

Are Feminists man Haters? Feminists' and Nonfeminists' Attitudes Toward Men

Despite the popular belief that feminists dislike men, few studies have actually examined the empirical accuracy of this stereotype. The present study examined self-identified feminists' and nonfeminists' attitudes toward men. An ethnically diverse sample ( N = 488) of college students responded to statements from the Ambivalence toward Men Inventory (AMI; Glick & Fiske, 1999 ). Contrary to popular beliefs, feminists reported lower levels of hostility toward men than did nonfeminists. The persistence of the myth of the man-hating feminist is explored.