The risk of skin cancer in women who carry BRCA1 or BRCA2 mutations

BACKGROUND

It has not been clearly established if skin cancer or melanoma are manifestations of BRCA1 or BRCA2 mutation carrier status. Estimating the risk of skin cancer is an important step towards developing screening recommendations.

METHODS

We report the findings of a prospective cohort study of 6,207 women from North America who carry BRCA1 or BRCA2 mutations. Women were followed from the date of baseline questionnaire to the diagnosis of skin cancer, to age 80 years, death from any cause, or the date of last follow-up.

RESULTS

During the mean follow-up period of eight years, 3.7% of women with a BRCA1 mutation (133 of 3,623) and 3.8% of women with a BRCA2 mutation (99 of 2,584) reported a diagnosis of skin cancer (including both keratinocyte carcinomas and melanoma). The cumulative risk of all types of skin cancer from age 20 to 80 years was 14.1% for BRCA1 carriers and 10.7% for BRCA2 carriers. The cumulative risk of melanoma was 2.5% for BRCA1 carriers and 2.3% for BRCA2 carriers, compared to 1.5% for women in the general population in the United States. The strongest risk factor for skin cancer was a prior diagnosis of skin cancer.

CONCLUSION

The risk of non-melanoma skin cancer in women who carry a mutation in BRCA1 or BRCA2 is similar to that of non-carrier women. The risk of melanoma appears to be slightly elevated. We suggest that a referral to a dermatologist or primary care provider for BRCA mutation carriers for annual skin examination and counselling regarding limiting UV exposure, the use of sunscreen and recognizing the early signs of melanoma might be warranted, but further studies are necessary.

Bilateral Oophorectomy and All-Cause Mortality in Women With BRCA1 and BRCA2 Sequence Variations

Importance

Preventive bilateral salpingo-oophorectomy is offered to women at high risk of ovarian cancer who carry a pathogenic variant in BRCA1 or BRCA2; however, the association of oophorectomy with all-cause mortality has not been clearly defined.

Objective

To evaluate the association between bilateral oophorectomy and all-cause mortality among women with a BRCA1 or BRCA2 sequence variation.

Design, Setting, and Participants

In this international, longitudinal cohort study of women with BRCA sequence variations, information on bilateral oophorectomy was obtained via biennial questionnaire. Participants were women with a BRCA1 or BRCA2 sequence variation, no prior history of cancer, and at least 1 follow-up questionnaire completed. Women were followed up from age 35 to 75 years for incident cancers and deaths. Cox proportional hazards regression was used to estimate the hazard ratios (HRs) and 95% CIs for all-cause mortality associated with a bilateral oophorectomy (time dependent). Data analysis was performed from January 1 to June 1, 2023.

Exposures

Self-reported bilateral oophorectomy (with or without salpingectomy).

Main Outcomes and Measures

All-cause mortality, breast cancer-specific mortality, and ovarian cancer-specific mortality.

Results

There were 4332 women (mean age, 42.6 years) enrolled in the cohort, of whom 2932 (67.8%) chose to undergo a preventive oophorectomy at a mean (range) age of 45.4 (23.0-77.0) years. After a mean follow-up of 9.0 years, 851 women had developed cancer and 228 had died; 57 died of ovarian or fallopian tube cancer, 58 died of breast cancer, 16 died of peritoneal cancer, and 97 died of other causes. The age-adjusted HR for all-cause mortality associated with oophorectomy was 0.32 (95% CI, 0.24-0.42; P < .001). The age-adjusted HR was 0.28 (95% CI, 0.20-0.38; P < .001) and 0.43 (95% CI, 0.22-0.90; P = .03) for women with BRCA1 and BRCA2 sequence variations, respectively. For women with BRCA1 sequence variations, the estimated cumulative all-cause mortality to age 75 years for women who had an oophorectomy at age 35 years was 25%, compared to 62% for women who did not have an oophorectomy. For women with BRCA2 sequence variations, the estimated cumulative all-cause mortality to age 75 years was 14% for women who had an oophorectomy at age 35 years compared to 28% for women who did not have an oophorectomy.

Conclusions and Relevance

In this cohort study among women with a BRCA1 or BRCA2 sequence variation, oophorectomy was associated with a significant reduction in all-cause mortality.

MRI Surveillance and Breast Cancer Mortality in Women With BRCA1 and BRCA2 Sequence Variations

Importance

Magnetic resonance imaging (MRI) surveillance is offered to women with a pathogenic variant in the BRCA1 or BRCA2 gene who face a high lifetime risk of breast cancer. Surveillance with MRI is effective in downstaging breast cancers, but the association of MRI surveillance with mortality risk has not been well defined.

Objective

To compare breast cancer mortality rates in women with a BRCA1 or BRCA2 sequence variation who entered an MRI surveillance program with those who did not.

Design, Setting, and Participants

Women with a BRCA1 or BRCA2 sequence variation were identified from 59 participating centers in 11 countries. Participants completed a baseline questionnaire between 1995 and 2015 and a follow-up questionnaire every 2 years to document screening histories, incident cancers, and vital status. Women who had breast cancer, a screening MRI examination, or bilateral mastectomy prior to enrollment were excluded. Participants were followed up from age 30 years (or the date of the baseline questionnaire, whichever was later) until age 75 years, the last follow-up, or death from breast cancer. Data were analyzed from January 1 to July 31, 2023.

Exposures

Entrance into an MRI surveillance program.

Main Outcomes and Measures

Cox proportional hazards modeling was used to estimate the hazard ratios (HRs) and 95% CIs for breast cancer mortality associated with MRI surveillance compared with no MRI surveillance using a time-dependent analysis.

Results

A total of 2488 women (mean [range] age at study entry 41.2 [30-69] years), with a sequence variation in the BRCA1 (n = 2004) or BRCA2 (n = 484) genes were included in the analysis. Of these participants, 1756 (70.6%) had at least 1 screening MRI examination and 732 women (29.4%) did not. After a mean follow-up of 9.2 years, 344 women (13.8%) developed breast cancer and 35 women (1.4%) died of breast cancer. The age-adjusted HRs for breast cancer mortality associated with entering an MRI surveillance program were 0.20 (95% CI, 0.10-0.43; P < .001) for women with BRCA1 sequence variations and 0.87 (95% CI, 0.10-17.25; P = .93) for women with BRCA2 sequence variations.

Conclusion and Relevance

Results of this cohort study suggest that among women with a BRCA1 sequence variation, MRI surveillance was associated with a significant reduction in breast cancer mortality compared with no MRI surveillance. Further studies of women with BRCA2 sequence variations are needed to ascertain these women obtain the same benefits associated with MRI surveillance.

Risk-reducing mastectomy and breast cancer mortality in women with a BRCA1 or BRCA2 pathogenic variant: an international analysis

BACKGROUND

Risk-reducing mastectomy (RRM) is offered to women with a BRCA1 or BRCA2 pathogenic variant, however, there are limited data on the impact on breast cancer mortality.

METHODS

Participants were identified from a registry of women with BRCA1/2 pathogenic variants. We used a pseudo-randomised trial design and matched one woman with a RRM to one woman without a RRM on year of birth, gene, and country. We estimated the hazard ratio (HR) and 95% confidence intervals (CI) for dying of breast cancer in the follow-up period.

RESULTS

There were 1654 women included; 827 assigned to the RRM arm and 827 assigned to the control arm. After a mean follow-up of 6.3 years, there were 20 incident breast cancers (including 15 occult cancers) and two breast cancer deaths in the RRM arm, and 100 incident breast cancers and 7 breast cancer deaths in the control arm (HR = 0.26; 95% CI 0.05-1.35; p = 0.11). The probability of dying of breast cancer within 15 years after RRM was 0.95%.

CONCLUSIONS

In women with a BRCA1 or BRCA2 pathogenic variant, RRM reduces the risk of breast cancer, and the probability of dying of breast cancer is low.

Breast Irradiation Is Well Tolerated in Carriers of a Pathogenic ATM Variant

PURPOSE

There are mixed and limited data regarding radiation therapy (RT) tolerance in carriers of a germline pathogenic or likely pathogenic (P/LP) ATM variant. We investigated RT-related toxic effects in carriers of an ATM variant who received treatment for breast cancer.

METHODS AND MATERIALS

We identified 71 patients treated with adjuvant RT for breast cancer who were carriers of a variant in ATM: 15 were classified as P/LP and 56 classified as variants of unknown significance (VUS). We additionally identified 205 consecutively treated patients during a similar timeframe who were either confirmed ATM wild type or had no prior genetic testing. RT plans were reviewed. Acute and chronic toxic effects were evaluated using Common Terminology Criteria for Adverse Events version 4.0 criteria. Fisher's exact tests for count data were performed to compare toxic effects between the cohorts (P/LP vs VUS vs control). Wilcoxon rank-sum testing was performed to assess for differences in patient characteristics.

RESULTS

The median toxicity follow-up was 19.4 months; median follow-up for the subcohorts was 13.3 months (P/LP), 12.6 months (VUS), and 23.3 months (control). There were no significant differences in radiation plan heterogeneity, receipt of a boost, or size of breast/chest wall planning target volume. There was greater use of hypofractionated RT in the control cohort (P = .023). After accounting for patient- and treatment-related factors that may affect toxic effects, we found no significant differences with respect to acute dermatitis, hyperpigmentation, moist desquamation, breast/chest wall pain, or breast edema. Additionally, we found no significant differences with respect to chronic breast/chest wall pain, induration, telangiectasia, or cosmetic outcome.

CONCLUSIONS

RT as part of the management of breast cancer was well tolerated in carriers of a P/LP ATM variant, with toxic effect profiles that were similar to those seen in patients without known ATM mutations. High rates of excellent or good cosmesis were observed in carriers of a P/LP ATM variant who underwent breast conservation.

The risks of cancer in older women with BRCA pathogenic variants: How far have we come?

BACKGROUND

The purpose of this study was to estimate the cumulative risks of all cancers in women from 50 to 75 years of age with a BRCA1 or BRCA2 pathogenic variant.

METHODS

Participants were women with BRCA1 or BRCA2 pathogenic variants from 85 centers in 16 countries. Women were eligible if they had no cancer before the age of 50 years. Participants completed a baseline questionnaire and follow-up questionnaires every 2 years. Women were followed from age 50 until a diagnosis of cancer, death, age 75, or last follow-up. The risk of all cancers combined from age 50 to 75 was estimated using the Kaplan-Meier method.

RESULTS

There were 2211 women included (1470 BRCA1 and 742 BRCA2). There were 379 cancers diagnosed in the cohort between 50 and 75 years. The actuarial risk of any cancer from age 50 to 75 was 49% for BRCA1 and 43% for BRCA2. Breast (n = 186) and ovarian (n = 45) were the most frequent cancers observed. For women who had both risk-reducing mastectomy and bilateral salpingo-oophorectomy before age 50, the risk of developing any cancer between age 50 and 75 was 9%.

CONCLUSION

Women with a BRCA1 or BRCA2 pathogenic variant have a high risk of cancer between the ages of 50 and 75 years and should be counselled appropriately.

Clinical characteristics of patients with PMS2 mutations

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Background: Lynch syndrome is a hereditary cancer predisposition syndrome caused by mutations in mismatch repair genes, MLH1, MSH2, MSH6, and PMS2. The cancer risks and clinical presentation of PMS2 associated Lynch syndrome is not well defined. This study outlines the characteristics of patients with PMS2 mutations identified in a large academic center. Methods: Patients with a pathogenic or likely pathogenic PMS2 variant identified between June 1, 2009 and Dec 31, 2021 were selected from a database at the Nancy and James Grosfeld Cancer Genetics Center at Beaumont Health. Data on demographics, cancer type and molecular testing were retrospectively analyzed. Results: A total of 92 patients from 61 families were found to carry a pathogenic or likely pathogenic variant in PMS2. The mean age at testing was 54 (19 to 95). A majority (50) of the family were Caucasian, while the rest were African American (2), Middle Eastern (2), Multiracial (8). The most common variant was c.137G > T (p.Ser46Ile), seen in twelve of 61 families. Forty-two patients (45.6%) had a personal history of cancer, with a mean age at diagnosis of 63. Of these forty-two patients, four had multiple malignancies, including one patient with six separate cancers. The most common malignancies were breast (16), colon (12), followed by uterine cancer (8), pancreatic (4), prostate (3) and other cancers. The mean age of diagnosis of breast cancer was 56 (41 to 78), colon cancers was 57 (32 to 75), uterine cancer 59 (50 to 72). Tumor IHC was performed in thirteen cases and 11 demonstrated loss of PMS2 protein expression. MSI was performed in 8 cases and 5 were unstable and 3 were stable. Conclusions: This study reveals the the clinical spectrum of cancers in PMS2 related Lynch syndrome. The most common cancers were breast, colon and uterine cancer, with older age of diagnosis. There was evidence of a more severe phenotype, exemplified by a patient with six cancers, suggesting higher penetrance. Further research is needed to better characterize the clinical presentation of PMS2 related Lynch syndrome.

Pathogenic ATM and BAP1 germline mutations in a case of early-onset, familial sarcomatoid renal cancer

Metastatic renal cell carcinoma (RCC) remains an incurable malignancy, despite recent advances in systemic therapies. Genetic syndromes associated with kidney cancer account for only 5%-8% of all diagnosed kidney malignancies, and genetic predispositions to kidney cancer predisposition are still being studied. Genomic testing for kidney cancer is useful for disease molecular subtyping but provides minimal therapeutic information. Understanding how aberrations drive RCC development and how their contextual influences, such as chromosome loss, genome instability, and DNA methylation changes, may alter therapeutic response is of importance. We report the case of a 36-yr-old female with aggressive, metastatic RCC and a significant family history of cancer, including RCC. This patient harbors a novel, pathogenic, germline ATM mutation along with a rare germline variant of unknown significance in the BAP1 gene. In addition, somatic loss of heterozygosity (LOH) in BAP1 and ATM genes, somatic mutation and LOH in the VHL gene, copy losses in Chromosomes 9p and 14, and genome instability are also noted in the tumor, potentially dictating this patient's aggressive clinical course. Further investigation is warranted to evaluate the association of ATM and BAP1 germline mutations with increased risk of RCC and if these mutations should lead to enhanced and early screening.

Abstract P5-15-08: Dietary supplement use among BRCA1/2mutation carriers

INTRODUCTIONWomen who carry BRCA1/2 mutations are at significantly increased risk of breast, ovarian, pancreatic and other cancer. Little is known regarding the use of dietary supplements among women harboring BRCA1/2 mutations. This study aims to characterize the utilization of and attitudes toward dietary supplement use in women who carry BRCA1/2 mutations. METHODSPatients identified through a cancer genetics clinic as harboring a BRCA1/2 mutation were invited to complete an electronic survey focused on their use of nutritional supplements. Inclusion criteria included female sex, age 21 years or older, confirmed BRCA1/2 mutation status, and no active cancer treatment. Participants answered questions regarding type of supplement, extent of physician involvement with dietary supplement usage, and perceptions toward dietary supplement use. A 10-point Likert-scale was used to measure the motivations for supplement use. RESULTSA total of 208 BRCA1/2 mutation carriers were invited to participate, and 68 surveys were completed. Patient characteristics are depicted in Table 1 and include high education level, active participation in exercise, and a significant uptake of risk-reducing surgery. Forty-nine participants (84%) reported using some type of dietary supplement including B vitamins, multivitamins, magnesium, zinc, fish oil, and turmeric being the most commonly reported. Twenty-seven patients (59%) reported that the supplements were not prescribed by a physician, however, 38 patients (70%) reported that their physician was aware of their supplement use. All respondents indicated that it is important for physicians to know what types of supplements they are taking, and the majority felt comfortable discussing this topic with their doctors. Patients reported that the motivating factors included enhancing the body’s immune system, reducing inflammation, and improving mood, stamina, and energy. Lastly, participants expressed an awareness that dietary supplements could be harmful and interact with other medications. CONCLUSIONOur results show a high utilization of dietary supplement use in women who carry a BRCA1/2 mutation, and while the majority of these supplements were not prescribed by a physician, patients placed high value on physician involvement with their supplement use. The primary motivators for use of dietary supplements in this high-risk population include benefit to the body’s immune system, and positive impact on mood, stamina, and energy. The results of this study underscore the significant interest in nutritional supplements in this high-risk population, but also reveal that there is room to improve upon physician engagement.

Table 1.Participant Demographic Information (N = 68)CharacteristicNo. (%)Age 18-25 26-34 35-39 40-49 50+3 (5.0%)12 (20.0%)7 (11.7%)10 (16.7%)28 (46.7%)Education Level High School or GED Some College College Degree Graduate/Professional Degree (PhD, MD)2 (3.3%)11 (18.3%)23 (38.3%)24 (40.0%)Past Breast Cancer/Ovarian Cancer Diagnosis Breast Cancer Ovarian Cancer22 (36.7%)2 (3.3%)Risk-Reducing Surgery Mastectomy Salpingo-Oophorectomy32 (53.3%)34 (56.7%)Moderate Exercise Every Day 2-3 Times per Week Once a Week Once or Twice a Month Rarely/Never15 (25.9%)26 (44.8%)10 (17.2%)2 (3.5%)5 (8.6%)

Citation Format: Ryan Rogers, Tara Rangarajan, Virginia Uhley, Kristina Ivan, Dana Zakalik. Dietary supplement use among BRCA1/2mutation carriers [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-15-08.

Adjuvant PARP Inhibitors in Patients With High-Risk Early-Stage HER2-Negative Breast Cancer and Germline BRCA Mutations: ASCO Hereditary Breast Cancer Guideline Rapid Recommendation Update

ASCO Rapid Recommendations Updates highlight revisions to select ASCO guideline recommendations as a response to the emergence of new and practice-changing data. The rapid updates are supported by an evidence review and follow the guideline development processes outlined in the ASCO Guideline Methodology Manual. The goal of these articles is to disseminate updated recommendations, in a timely manner, to better inform health practitioners and the public on the best available cancer care options.

Improved universal tumor screening program with paired testing: Experience at a large community-based teaching hospital

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Background: Lynch syndrome (LS) is the most common cause of hereditary predisposition to colon, endometrial, and other cancers. The universal tumor screening program for LS at Beaumont Health (BH) utilizes immunohistochemistry (IHC) of the mismatch repair (MMR) proteins to identify patients for genetics evaluation. We present the 8-year experience of the program at a large community-based teaching hospital. Methods: The MMR IHC results for all colorectal cancer (CRC) resection specimens screened from August 2012 to September 2020 were reviewed. Specimens with absent MLH1 and PMS2 were evaluated for MLH1 promoter hypermethylation with reflex to BRAF V600E mutation analysis. All abnormal results were referred for cancer genetics evaluation. The distribution of abnormal MMR and germline genetic testing results was analyzed. Results: Specimens from 2361 CRC resections were screened, and 511 specimens had abnormal MMR IHC (22%). Most cases of absent MLH1 and PMS2 were explained by hypermethylation or BRAF analysis (n = 338, 66% of all abnormal, 89% of MLH1 and PMS2). Of the remaining cases showing MMR deficiency (n = 173), the most common result was absence of MSH2 and MSH6 (n = 67), followed by absence of MLH1 and PMS2 (n=41, see table). Germline genetic testing of 83 individuals with abnormal MMR IHC revealed 49 cases of Lynch syndrome [MLH1 (n=9), MSH2 (n= 25), MSH6 (n=7), PMS2 (n=7), EPCAM (n=1)]. A significant proportion of cases (n=34, 40%) had negative germline testing, and had unexplained MMR deficiency. Paired germline/tumor testing was implemented in 2017, and 14 patients had this analysis. Using this approach, 5 individuals were identified to have somatic mutations explaining their result, and the proportion of unexplained cases was reduced to 29% (n = 4). Conclusions: Recent advances in cancer screening and therapeutics have underscored the importance of analyzing tumors for mismatch repair deficiency (dMMR), with known challenges to implementation and interpretation of results. The BH cancer genetics program has demonstrated successful growth of a universal tumor screening program over 8 years. This has led to the identification of a large number of dMMR tumors (22% of all CRC resections) and LS cases (2% of all CRC resections), which impacts management for patients and their families. Recent implementation of paired germline/tumor testing has improved the testing algorithm, and resulted in more accurate interpretation of a greater proportion of abnormal IHC results. This combined approach allows for focused high-risk screening for LS patients, access to novel therapeutic interventions including immune therapies for patients with dMMR tumors, and future precision oncology approaches.[Table: see text]

Twenty-one-gene recurrence score (RS) in germline (g)CHEK2 mutation-associated versus sporadic breast cancers (BC): A multi-site case-control study

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Background: Genomic assays, such as RS, are used to determine chemotherapy benefit in early-stage, estrogen receptor (ER)- and/or progesterone receptor (PR)-positive, HER2 negative BC patients (pts). Currently, guidelines to use pts’ germline genetic testing results to guide adjuvant therapy are lacking. Several reports have indicated worse outcomes for BC pts with g CHEK2 pathogenic variants (PV). We investigated whether PV in CHEK2 were associated with increased RS. Methods: Patient-level clinical data and RS were derived from electronic medical records of seven medical centers between years 2013-17. Confirmation of RS using the Genomic Health provider portal was performed. 38 pts with germline PV in CHEK2 (15 pts/39.5% with c.1100delC mutation) and RS score (cases) were matched with BC pts whose genetic testing did not identify PV (controls) using a 1:2 matching schema. Pts were matched based on age at diagnosis and lymph node (LN) status. LN negative pts were further matched based on T-stage. A multivariate random intercept linear mixed model of CHEK2 mutation status on RS was performed, adjusting for PR. A secondary ordinal univariate analysis was conducted that categorized RS into low, intermediate and high risk ( < 18, 18-30, and > 30, respectively). P-values were reported based on a null hypothesis of no effect against a two-sided alternative. Results: The median RS for cases was 19.5 (interquartile range [IQR]: 15 to 25) and the median RS for controls was 18 (IQR: 12 to 22). A greater proportion of cases were categorized as high risk (10.5%) compared to controls (5.6%), and a smaller proportion of cases were categorized as low risk (36.8%) compared to controls (49.3%). Cases had higher grade and increased proportion of PR-negative BC as compared with controls (grade 1: 12.1% of cases versus 32.4% of controls; PR-negative: 7.9% of cases versus 5.6% of controls). The variables used to match cases and controls (age, lymph node status, and T-stage) had similar summary statistics. The RS was 1.97-point higher in pts with g CHEK2 PV compared to controls, after adjusting for PR (95% confidence interval [CI]: 1.02-point lower to 4.96-point higher; p = 0.194). The secondary analysis of CHEK2 mutation status on an ordinal RS risk group yielded comparable results; on average, the odds of being high risk compared to the combined intermediate/low risk groups was 1.72 times higher in cases compared to controls (95% CI: 0.77 to 3.80; p = 0.181), but these differences were not significant. Conclusions: Our case-control study did not show a statistically higher RS for BC that develops in pts with g CHEK2 PV. Further studies are warranted to evaluate the association between type of CHEK2 PV (frameshift versus missense) and other modifying genetic variables and RS.

Management of Hereditary Breast Cancer: American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology Guideline

PURPOSE

To develop recommendations for management of patients with breast cancer (BC) with germline mutations in BC susceptibility genes.

METHODS

The American Society of Clinical Oncology, American Society for Radiation Oncology, and Society of Surgical Oncology convened an Expert Panel to develop recommendations based on a systematic review of the literature and a formal consensus process.

RESULTS

Fifty-eight articles met eligibility criteria and formed the evidentiary basis for the local therapy recommendations; six randomized controlled trials of systemic therapy met eligibility criteria.

RECOMMENDATIONS

Patients with newly diagnosed BC and BRCA1/2 mutations may be considered for breast-conserving therapy (BCT), with local control of the index cancer similar to that of noncarriers. The significant risk of a contralateral BC (CBC), especially in young women, and the higher risk of new cancers in the ipsilateral breast warrant discussion of bilateral mastectomy. Patients with mutations in moderate-risk genes should be offered BCT. For women with mutations in BRCA1/2 or moderate-penetrance genes who are eligible for mastectomy, nipple-sparing mastectomy is a reasonable approach. There is no evidence of increased toxicity or CBC events from radiation exposure in BRCA1/2 carriers. Radiation therapy should not be withheld in ATM carriers. For patients with germline TP53 mutations, mastectomy is advised; radiation therapy is contraindicated except in those with significant risk of locoregional recurrence. Platinum agents are recommended versus taxanes to treat advanced BC in BRCA carriers. In the adjuvant/neoadjuvant setting, data do not support the routine addition of platinum to anthracycline- and taxane-based chemotherapy. Poly (ADP-ribose) polymerase (PARP) inhibitors (olaparib and talazoparib) are preferable to nonplatinum single-agent chemotherapy for treatment of advanced BC in BRCA1/2 carriers. Data are insufficient to recommend PARP inhibitor use in the early setting or in moderate-penetrance carriers. Additional information available at www.asco.org/breast-cancer-guidelines.

Characteristics and survival of secondary male breast cancer: SEER database analysis

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Background: Male breast cancer (MBC) is rare accounting for less than 0.5% of all cancer diagnoses in men. We used the term secondary male breast cancer (sMBC) to refer to ipsilateral and contralateral recurrences in addition to new primary MBC. Given its low incidence, data regarding the risk of developing sMBC and its characteristics are scarce. Methods: Multiple Primary Standardized Incidence Ratios (MP-SIR) session was conducted from the SEER*Stat software. We included all patients diagnosed with stage I,II and III MBC between 1990 to 2015 from the Surveillance Epidemiology and End Results (SEER) 18 registry. The standardized incidence ratio (SIR) was calculated as an estimate of the risk of a second primary malignancy based on the incidence in the general population. Descriptive statistics and Kaplan-Meier analysis were performed using SPSS software. Results: Among all 2321 men diagnosed with a first primary MBC during the study period, 28 patients had a subsequent diagnosis of MBC. The risk of sMBC was significantly elevated with SIR of 33.12 (95% CI, 22.18 – 47.56). The median latency period between the initial and subsequent diagnoses was 5.9 years. 82.1% of the patients were White, 14.3% Black and 3.6% Asian/Pacific Islander. Majority of the cases constituting 85.7% of sMBC were diagnosed in the contralateral breast. 67.8% of the sMBC remained hormone receptors status positive similar to the initial status of the primary diagnosis. 42.9% of the sMBC patients were diagnosed with stage I, 17.9% with stage II, 3.6% with stage III, 17.9% with stage IV and 17.9% of unknown stage. The median overall survival for sMBC was 96 months (95% CI, 11.3-180.6). We also found an increased risk of developing liver cancer (SIR: 2.16), prostate cancer (SIR: 1.29), thyroid cancer (SIR: 3.08) and acute myeloid leukemia (SIR: 2.4) in individuals after a diagnosis of MBC. Conclusions: Men diagnosed with breast cancer are at increased risk of sMBC in addition to other malignancies which require careful monitoring after completing initial treatment. Contralateral mammogram screening or prophylactic contralateral mastectomy can be considered based on patient’s preferences and values.

Heterozygous germline ATM mutations in breast cancer: A single academic center experience

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Background: Heterozygous germline ATM mutation carriers have an increased risk of developing breast, pancreas, and other cancers. The clinical and pathologic characteristics of ATM-associated breast cancers have not been well defined. Methods: Patients who underwent multigene panel testing (MGPT) between 2013-2019 and identified to harbor ATM mutations were included in the study. We evaluated demographics, pathology, and surgical management of our ATM mutation carriers with breast cancer. Results: At total of 319 individuals were identified to have variants in ATM, of which 114 were pathogenic/likely pathogenic. The majority of patients were female (82%) and Caucasian (88%). A total of 56 patients (49%) had a personal cancer diagnosis, the most common of which was breast cancer (n = 39). Nine individuals had more than one primary malignancy. The mean age at breast cancer diagnosis was 52, with a range of 25-82. The majority of patients had invasive ductal carcinoma (74%), grade 2 or 3 (90%), and ER and /or PR positive (87%). Of those with known HER2 status, 24% were positive. Thirty-nine percent of patients were lymph node positive, and 42% had lymphovascular invasion. The most common stage at diagnosis was 2 (53%). Of the 39 mutation carriers with breast cancer, 16 (42%) received radiation therapy, and 16 underwent bilateral mastectomy. Of 114 ATM positive patients, there were 55 distinct variants. Sixteen (14%) individuals had a mutation in additional cancer predisposition genes. One variant, c.5015delG, was identified in ten patients in a large, consanguineous Iraqi family with an extensive history of pancreatic and other cancers. Eight individuals were identified to have the known high-penetrance variant, c.7271T > G. Conclusions: Our study describes the clinical and pathological characteristics of ATM mutations carriers with breast cancer. The majority of patients had intermediate to high grade disease, hormone receptor positive, with a suggestion of a higher rate of HER2 positivity and lymph node involvement. Additional studies are needed to elucidate the unique characteristics of ATM-associated breast cancer, which may have implications for personalized management.

ATM mutation carriers and family history of pancreatic cancer

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Background: Multigene panel testing (MGT) is commonly utilized in patients with a personal or family history of cancer. One of the more common gene mutations identified is in the ATM gene, associated with a moderately increased risk of breast and other cancers. There are reports of an association with pancreatic cancer, however the exact risks are unclear. The aim of this study is to describe the family history of pancreatic cancer in a cohort of ATM mutation carriers, and to evaluate possible genotype/phenotype correlation. Methods: Patients who underwent MGT, between ‘13 and ‘19, and tested positive for a pathogenic/likely pathogenic ATM mutation were included in this study. Family history, with a focus on pancreatic cancer, and genetic testing results were analyzed. Results: A total of 114 patients were identified to carry an ATM mutation. Twenty-two (19.3%) individuals had a family history of pancreatic cancer in a close relative, and of those, 13 (11.4%) had an affected first degree relative, and 11 (9.6%) had an affected second degree relative. Among the families with pancreatic cancer, 20 close relatives had a personal history of pancreatic cancer, with the youngest diagnosed at age 40, the oldest diagnosed at age 91, and a mean age of diagnosis of 66.5 years. Thirteen unique variants were identified: 4 splice site, 3 missense, 3 frameshift, 1 nonsense, and 1 silent. Two families had the known high-penetrance ATM mutation, c.7271T > C (p.V2424G). Conclusions: This study describes the association of pancreatic cancer in individuals found to carry pathogenic ATM mutations. A significant proportion (19.3%) of patients had a family history of pancreatic cancer in a close relative, diagnosed as young as age 40. The mean age of diagnosis was slightly younger than the average age in the general population (age 70). As pancreatic cancer screening continues to improve, this information will be an important component to help guide cancer risk assessment and future screening recommendations for ATM mutation carriers. Additional larger studies are needed to further characterize pancreatic cancer risks in patients with ATM gene mutations.

Long-term outcomes following a diagnosis of ovarian cancer at the time of preventive oophorectomy among BRCA1 and BRCA2 mutation carriers

INTRODUCTION

Preventive bilateral salpingo-oophorectomy is the most effective means of reducing the risk of ovarian cancer among women with an inherited BRCA1 or BRCA2 mutation. Some women are diagnosed with an invasive cancer (ovarian or fallopian tube) at the time of preventive surgery, referred to as an 'occult' cancer. The survival experience of these women is not known.

METHODS

We estimated the 10-year survival for 52 BRCA mutation carriers diagnosed with an occult ovarian or fallopian tube cancer at the time of preventive bilateral salpingo-oophorectomy.

RESULTS

The mean age at diagnosis was 51.6 (range 33-69) years. All were serous cancers (although 14 were missing information on histologic subtype). Of the 20 cases with information available on stage at diagnosis, 10 were stage I, 1 was stage II, and 9 were stage III (n=32 missing). After a mean of 6.8 years, 12 women died (23%). The 10-year all-cause survival was 74%.

CONCLUSION

Although based on only 52 cases, these findings suggest a more favorable prognosis for BRCA mutation carriers diagnosed with an occult rather than incident disease.

Utilization of a breast cancer risk assessment tool by internal medicine residents in a primary care clinic: impact of an educational program

Background

Despite strong evidence of benefit, breast cancer risk assessment and chemoprevention are underutilized by primary care physicians. This study evaluates the impact of an educational program on knowledge and utilization of the NCI Breast Cancer Risk Assessment Tool (BCRAT) by internal medicine residents.

Methods

Internal medicine residents at the primary care clinic at William Beaumont Hospital participated in an educational program on breast cancer risk assessment and chemoprevention. A questionnaire was used to assess knowledge and practice before and after participation. Electronic health records of women between the ages of 35 and 65 who were seen by participating residents for annual health exams between Dec 15, 2015 and Dec 14, 2016 were reviewed. Utilization of BCRAT by the residents was compared pre- and post-educational program.

Results

A total of 43 residents participated in the study. 31 (72.1%) residents reported no prior knowledge about BCRAT. The remaining 12 (27.9%) reported limited knowledge of BCRAT, but the majority of these (n = 10, 83.3%) had not used it in the last six months. For each question on the pre-educational knowledge assessment, fewer than 10% of the residents responded correctly. After implementation of the educational program, there was a significant increase in the proportion of residents who answered correctly (Range: 67 to 100%, p < 0.001).

Electronic health records of 301 clinic patients were reviewed, 118 (39.2%) in the pre-educational program group and 183 (60.8%) in the post-educational program group. There was a higher use of BCRAT in the post-educational program group compared to the pre-intervention group (3.8% vs. 0%, p < 0.05). However, a majority (n = 294, 98.7%) of eligible patients from both groups did not undergo breast cancer risk assessment.

Conclusions

Our study demonstrates that an educational intervention improved residents’ knowledge of BCRAT. Despite this improvement, a significant proportion of patients did not undergo breast cancer risk assessment. Expanding the scope and duration of this intervention and combining it with innovative use of technology to improve utilization should be the subject of future investigation.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5418-6) contains supplementary material, which is available to authorized users.

Prospective evaluation of body size and breast cancer risk among BRCA1 and BRCA2 mutation carriers

BACKGROUND

Although evidence suggests that larger body size in early life confers lifelong protection from developing breast cancer, few studies have investigated the relationship between body size and breast cancer risk among BRCA mutation carriers. Therefore, we conducted a prospective evaluation of body size and the risk of breast cancer among BRCA mutation carriers.

METHODS

Current height and body mass index (BMI) at age 18 were determined from baseline questionnaires. Current BMI and weight change since age 18 were calculated from updated biennial follow-up questionnaires. Cox proportional hazards models were used to estimate the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

Among 3734 BRCA mutation carriers, there were 338 incident breast cancers over a mean follow-up of 5.5 years. There was no association between height, current BMI or weight change and breast cancer risk. Women with BMI at age 18 ≥22.1 kg/m2 had a decreased risk of developing post-menopausal breast cancer compared with women with a BMI at age 18 between 18.8 and 20.3 kg/m2 (HR 0.49; 95% CI 0.30-0.82; P = 0.006). BMI at age 18 was not associated with risk of pre-menopausal breast cancer.

CONCLUSIONS

There was no observed association between height, current BMI and weight change and risk of breast cancer. The inverse relationship between greater BMI at age 18 and post-menopausal breast cancer further supports a role of early rather than current or adulthood exposures for BRCA-associated breast cancer development. Future studies with longer follow-up and additional measures of adiposity are necessary to confirm these findings.

Abstract P4-06-03: Characteristics of CHEK2 mutation carriers in a large academic health center in Michigan

Background: Germline mutations in CHEK2, a cell-cycle checkpoint kinase, are associated with increased susceptibility to breast, colon, and other cancers. The clinical characteristics and cancer risks of patients with CHEK2 mutations is under investigation.

Methods: Patients identified with a pathogenic germline CHEK2 mutation between September 2013 and April 2017 were evaluated. Clinical multigene panel testing using next generation sequencing technologies was utilized. All patients received comprehensive pre- and post-test genetic counseling. Genetic testing results, demographics, tumor characteristics and outcomes were analyzed.

Results: A total of 107 CHEK2 mutation carriers were identified, of whom 88 (82%) were females. The vast majority were Caucasian (99%), and of those, 17 (16%) had Ashkenazi Jewish ancestry. The median age at time of genetic testing was 52 (range: 22-89). The most common mutations identified were: I157T (28%), c.1100delC (27%), p.S428F (15%) and c.1427C&gt;T (9%). Seven of these patients (7%) were found to carry a second pathogenic cancer risk mutation: BRCA, ATM, NBN, NF1, and MUTYH. One patient was found to carry 3 pathogenic mutations (1100delC, ATM, and BRCA). Sixty-three (59%) patients had a prior diagnosis of malignancy, with a mean age of diagnosis of 53. Of the 88 females, the most common type of malignancy was breast cancer (55%), with a mean age of diagnosis of 52 (range: 35-79). Of the 19 males, breast cancer was seen in 4 patients. The most common known histopathology was invasive ductal carcinoma (72%), followed by DCIS (15%), invasive lobular carcinoma (9%), and papillary carcinoma (4%). Majority of the patients had breast tumors with low or moderate grade (62%), less than two centimeters (61%), node negative (70%), and estrogen/progesterone receptor positive/HER2neu negative (96%). Two patients had triple negative breast cancers. Of the 48 female mutation carriers with breast cancer, 38% underwent bilateral mastectomy. The 1- and 5-year survival was 100% with a median follow up of 57 months. Five of the 48 females developed a contralateral breast cancer, with a median time to contralateral recurrence of 6 years (range: 3-17). Two patients developed in-breast tumor recurrence at 9 and 19 years, respectively. Other cancers observed were papillary thyroid cancer (3 patients), melanoma (2 patients), and prostate (2 patients). One patient developed angiosarcoma of the chest wall two years after radiation therapy.

Conclusion: Our study describes the unique clinical characteristics of CHEK2 mutation carriers in a US-based clinic at Beaumont Health. Majority of breast cancers were early stage, hormone receptor positive and demonstrated excellent outcomes. Despite the early stage, a significant proportion of patients underwent bilateral mastectomy. Additional pathogenic mutations were identified in 10% of patients; validating the importance of panel testing in assessing cancer risk. Future studies are needed to better define the clinical presentation, cancer risks, mutational spectrum, and outcomes of CHEK2 mutation carriers in order to provide tailored screening and management guidelines for this emerging population.

Citation Format: Blankenship LM, Yadav S, Yumpo Cardenas P, Zakalik D. Characteristics of CHEK2 mutation carriers in a large academic health center in Michigan [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 P4-06-03.

Male BRCA mutation carriers: clinical characteristics and cancer spectrum

Background

Mutations in BRCA1 and BRCA2 (BRCA1/2) genes are associated with an increased risk of breast and ovarian cancers in women. The cancer characteristics of men with BRCA1/2 mutations are less well studied. This study describes the unique cancer characteristics of male BRCA1/2 mutation carriers at our institution.

Methods

We performed a retrospective chart review on male patients who were seen between January 2004 and December 2014 and tested positive for a BRCA1/2 mutation. We evaluated clinical characteristics, pathology findings, treatment selection and survival.

Results

A total of 102 male patients were identified who tested positive for a BRCA1/2 deleterious mutation. Of these 102 patients, 33 (32%) had a diagnosis of cancer. Of these 33 patients with cancer, the majority (20 patients) were found to carry a BRCA2 mutation. Median age of cancer diagnosis was 65 years (Range: 35-75 years). Of the 33 patients diagnosed with cancer, 8 had two or more cancers, including 1 patient who had 4 cancers. Prostate cancer was the most commonly diagnosed cancer, seen in 13 patients, 11 of whom were BRCA2 positive. These cancers tended to have higher Gleason scores and elevated PSA levels. The majority of these prostate cancer patients were alive and disease free at a median follow-up of 7.4 years. Male breast cancer was the second most common cancer seen in 9 patients, all of whom were BRCA2 positive. The majority of these cancers were high grade, hormone receptor positive and associated with lymph node metastases. There were no breast cancer related deaths. Other cancers included bladder cancer, pancreatic cancer, melanoma and other skin cancers.

Conclusions

This study describes the cancer characteristics and outcomes of male BRCA1/2 mutation carriers. A third of male BRCA1/2 mutation carriers had a diagnosis of cancer. A significant number of patients (mostly BRCA2 mutation positive) developed multiple cancers, which may have important implications for cancer screening and prevention. Despite having high grade histology and advanced stage at diagnosis, male BRCA1/2 mutation carriers with breast and prostate cancer demonstrated a favorable 5-year survival.

Outcomes of retesting BRCA negative patients using multigene panels

The utility of multigene panels in retesting patients who previously tested negative for a pathogenic mutation by BRCA1/2 testing is not well established. Patients who previously tested negative for a pathogenic BRCA1/2 mutation by standard sequencing, and who were seen in cancer genetics center between November 1, 2012 and June 30, 2015 for additional testing utilizing multigene panels, were identified using our genetic testing registry. Data on demographics, personal and family history of cancer, results of panel testing and the impact on patient management was collected retrospectively. A total of 122 patients underwent retesting during the study period. Thirteen (11%) pathogenic mutations were identified in the following genes: CHEK2(4), PALB2(3), ATM(2), CDH1, APC, BARD1 and MRE11A. Eleven out of these thirteen mutations were deemed actionable based on published guidelines. Of these eleven, seven patients had an actual change in clinical management as a result of retesting. Furthermore, retesting also led to a change in clinical management in the two patients with mutations in genes (BARD1 and MRE11A) which do not have clear guidelines for management. There were no significant differences in demographics and personal and family history of cancer between patients who tested positive and those who tested negative on retesting. This study demonstrates the clinical utility of multigene panels in a group of high risk individuals who previously tested negative for a BRCA1/2 mutation. This retesting approach revealed a pathogenic mutation in 11% of cases. Retesting led to significant change in clinical management in a majority of patients with actionable mutations (7 out of 11), as well as in those with mutations in genes which do not have specific management guidelines.

Preoperative genetic testing impacts surgical decision making in BRCA mutation carriers with breast cancer: a retrospective cohort analysis

Background

The impact of timing of genetic testing on surgical decision making in women with breast cancer and BRCA mutation is not well known.

Methods

Women who were found to carry a deleterious BRCA mutation and had been diagnosed with breast cancer were identified from a database at Beaumont Health. Women who had received BRCA positive results at least a day prior to their index surgery were considered to be aware of their mutation status prior to surgery. Baseline characteristics and surgical choices were compared between women who were aware of their mutation status prior to surgery and those who were not. Fischer’s exact test was used for categorical variables and Mann–Whitney U-Test was used for continuous variables.

Results

A total of 220 patients were included in the final analysis, 208 (94.5%) with unilateral breast cancer and 12 (5.5%) with bilateral breast cancer. Out of the 208 patients with unilateral breast cancer, 106 (51.0%) patients were aware of their mutation status prior to index surgery while 102 (49%) were not. A significantly (p < 0.05) higher proportion of women underwent contralateral prophylactic mastectomy in the group that was aware of their mutation status prior to index surgery compared to the group that was not (76.4% vs 14.7%).

Conclusions

Our study demonstrates that knowledge of BRCA mutation status impacts surgical decision making in favor of bilateral mastectomy in patients who are aware of their results prior to index surgery. This finding supports the practice of preoperative genetic testing in patients with newly diagnosed breast cancer.

Squamous cell carcinoma of the breast in the United States: incidence, demographics, tumor characteristics, and survival

PURPOSE

Squamous cell carcinoma of breast accounts for less than 0.1% of all breast cancers. The purpose of this study is to describe the epidemiology and survival of this rare malignancy.

METHODS

Data were extracted from the National Cancer Institute's Surveillance, Epidemiology and End Results Registry to identify women diagnosed with squamous cell carcinoma of breast between 1998 and 2013. SEER*Stat 8.3.1 was used to calculate age-adjusted incidence, age-wise distribution, and annual percentage change in incidence. Kaplan-Meier curves were plotted for survival analysis. Univariate and multivariate Cox proportional hazard regression model was used to determine predictors of survival.

RESULTS

A total of 445 cases of squamous cell carcinoma of breast were diagnosed during the study period. The median age of diagnosis was 67 years. The overall age-adjusted incidence between 1998 and 2013 was 0.62 per 1,000,000 per year, and the incidence has been on a decline. Approximately half of the tumors were poorly differentiated. Stage II was the most common stage at presentation. Majority of the cases were negative for expression of estrogen and progesterone receptor. One-third of the cases underwent breast conservation surgery while more than half of the cases underwent mastectomy (unilateral or bilateral). Approximately one-third of cases received radiation treatment. The 1-year and 5-year cause-specific survival was 81.6 and 63.5%, respectively. Excluding patient with metastasis or unknown stage at presentation, in multivariate Cox proportional hazard model, older age at diagnosis and higher tumor stage (T3 or T4) or nodal stage at presentation were significant predictors of poor survival.

CONCLUSIONS

Our study describes the unique characteristics of squamous cell carcinoma of breast and demonstrates that it is an aggressive tumor with a poor survival. Older age and higher tumor or nodal stages at presentation were independent predictors of poor survival for loco-regional stages.

Abstract P5-08-14: Synchronous bilateral breast cancer compared to unilateral breast cancer: A population based study

Introduction: The clinical presentation and outcome of synchronous bilateral invasive breast cancer compared to unilateral breast cancer is not well studied. In this study, we present a population based comparison of tumor characteristics and survival between invasive unilateral and bilateral breast cancer.

Methods: Data from National Cancer Institute- Surveillance, Epidemiology and End Results (SEER) was analyzed to identify women who had a diagnosis of invasive ductal carcinoma (ICD-O-3: 8500/3) between the years 2000 and 2013. Women who were diagnosed with an invasive contralateral breast cancer within two months of initial diagnosis were classified under synchronous bilateral breast cancer group. Women who developed a contralateral breast cancer between three to twelve months of diagnosis were excluded. All women who did not develop a second breast cancer, or developed it after twelve months of initial diagnosis were classified under unilateral breast cancer group. Patients with an in-situ breast cancer diagnosis in the contralateral breast within twelve months of diagnosis of invasive ductal carcinoma were excluded. Patients with metastatic disease and unknown stage at presentation were excluded. Tumor characteristics and survival were compared between the two groups using the index case only. Mann-Whitney U test was used for continuous variables while Chi-square test was used for categorical variables. Kaplan-Meier curves and Cox proportional hazard regression models were used to compare survival. All data analysis was performed using SPSS 21.

Results: A total of 414,766 patients met our inclusion criteria. Of these, 3,590 patients were in the synchronous bilateral breast cancer group, while 411,176 were in the unilateral breast cancer group. Compared to unilateral breast cancer patients, bilateral breast cancer patients were slightly older (62 Vs 59, p&lt;0.05) and were more likely to have higher T, N or overall stage at presentation. Their tumors were also more likely to be estrogen or progesterone receptor positive (p&lt;0.05). Patients with bilateral breast cancer also had higher rates of mastectomy (63.3% Vs 39.1%, p&lt;0.05).

Patients with bilateral breast cancers had a significantly worse survival compared to patients with unilateral breast cancer (Table 1). In a multivariate Cox proportional hazard regression, adjusting for age at diagnosis, T-Stage, N-Stage, overall stage, hormone receptor status, type of surgical treatment and radiation therapy, bilateral breast cancers had a mortality hazard ratio of 1.48 (95% CI: 1.35 – 1.62, p&lt;0.001) compared to unilateral breast cancers.

Conclusions: Our study demonstrates that bilateral breast cancer has a worse prognosis compared to invasive unilateral breast cancer. These findings have important implications for patients, and contribute to our understanding of the unique outcomes of bilateral breast cancer which will guide treatment and follow up.

Table 1: Survival of unilateral vs bilateral breast cancer Unilateral breast cancerBilateral breast cancer5-year cause specific survival91.7%86.5%10-year cause specific survival86.1%77.7%

Citation Format: Yadav S, Zakalik D. Synchronous bilateral breast cancer compared to unilateral breast cancer: A population based study [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 P5-08-14.

Abstract P2-09-06: Multi-gene panel testing for hereditary cancer risk

Background: Multi-gene panels are widely available for assessing hereditary cancer risk in high risk individuals. Due to the use of these panels, many genetic mutations other than BRCA 1 or 2 can be detected which can potentially affect management. This study presents the results of multi-gene panel testing performed at Beaumont Health System.

Methods:All patients who underwent multi-gene panel testing at Beaumont Health System between November 1, 2012 and January 15, 2015 were included in this study. This cohort consisted of patients who met criteria for genetic testing due to personal or family history. All patients received comprehensive pre and post-test genetic counseling. The panels ranged from 5 to 43 genes associated with risk for breast and other cancers.

Results: 653 multi-gene panel tests were performed. The majority of these consisted of either a 5 gene high risk breast panel (25%), an 18 gene moderate to high risk breast panel (21%), or a 9 gene high risk breast and gynecologic panel (17%). 184 variants of undetermined significance (VUS) were identified with a pooled VUS rate of 28%. Among the commonly used panels, there was a positive correlation between VUS rate and the number of genes included in the panel (r = 0.86, p = 0.01, Range 6% to 70%). A pathogenic mutation was identified in one or more genes in 65 (10%) panels for a total of 67 mutations. Of these, 17 mutations were in BRCA1 or BRCA2 gene. Fifty non-BRCA deleterious mutations were identified with the following frequencies: CHEK2(12), MUTYH(7 monoallelic, 1 biallelic), TP53(4), PTEN(4), ATM(4), MSH6(3), PALB2(3), MSH2(2), CDH1(2), APC(2), NF1(2), BARD1(2), MLH1(1) and PMS2(1). Of these non-BRCA mutations, 41(82%) had a significant impact on management.

Conclusions: Our study demonstrates that multi-gene panel testing identifies several genes that can impact management and would likely not have been discovered by pedigree analysis alone. However, this added detection is associated with a higher VUS rate, especially using larger panels. Further research is needed to better define the role of multi-gene panel testing in high risk patients, with a focus on choosing appropriate genes, understanding the magnitude of cancer risk and delineating impact on management.

Citation Format: Yadav S, Ladkany R, Fulbright J, Dreyfuss H, Reeves A, Campian S, Thomas V, Zakalik D. Multi-gene panel testing for hereditary 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 P2-09-06.

Outcomes of retesting BRCA-negative patients using multigene panels

23

Background: New technologies for identifying hereditary predisposition to breast cancer have led to the discovery of novel genes associated with cancer risk. This has prompted re-evaluation of patients who previously tested negative for BRCA1/2 gene mutations, with a possibility of discovering new genes which may impact management. This study reports on the results of retesting patients who previously were negative for BRCA1/2. Methods: Patients who tested negative for BRCA1/2 mutations who had significant personal and family history were referred back to the Cancer Genetics Center between February 1, 2012 and May 30, 2105 for discussion of additional testing. A detailed personal and family history was reviewed, and patients were counseled about the genetics and clinical implications of panel testing for multiple breast cancer genes. Panel testing using next generation sequencing technologies was ordered. Patients were seen in follow up for discussion of results and management. Results: A total of 12 pathogenic mutations were identified during the study period. The genes and frequencies of these mutations were: CHEK2(3), PALB2(3), ATM(2), APC(1), BARD(1), CDH(1), MUTYH(1). There were 33 variants of undetermined significance(VUS) in 27 patients. 5 of these were seen in patients with a known pathogenic mutation; 3 others were later classified as benign. The frequencies of these VUSs were: ATM (9), PALB2(3), BARD1 (3), PTEN(3), PMS2(3), MSH6(2), CHEK2 (1), MYH(1), RAD51(1), BRIP1(2), NF1(1), BMPR1A(1). Of the 46 patients who had their initial BRCA testing and repeat panel testing between February 1, 2012 and May 30, 2015, 6 (13%) tested positive for a pathogenic mutation. Conclusions: This study demonstrates the feasibility and potential clinical benefit of retesting individuals who previously tested negative for BRCA1/2 mutation. This approach had a significant management impact on patients and their families, with a 13% detection rate of pathogenic mutations. The success of retesting is predicated upon an infrastructure of provider and patient education, pre and post genetic counseling and serves as a model for other centers.

Surgical decisions of newly diagnosed breast cancer patients following genetic referral

40

Background: In response to many recent publications and mandates to assure referrals to genetic counseling for oncology patients, the Royal Oak (RO) Breast Care Center (BCC) at Beaumont Health System (BHS) evaluated the surgical outcomes of genetic referral(GR) in breast cancer (BC) patients. The goal of this study was to determine the impact of GR on surgical decision making and evaluate outcomes in this population. Methods: A retrospective chart review was performed, to identify patients who had a BC diagnosis and met criteria for GR from July 2012- July 2014. Age, histology, laterality of cancer, prior history of cancer, neoadjuvant chemotherapy, plastic surgery consultation, MRI, reason for MRI, additional testing, type of surgery, laterality of surgery, reconstruction, lymph node surgery, and time from diagnosis to surgery were evaluated using Chi Square analysis. Results: A total of 506 patients with a new BC diagnosis seen at the RO BCC at BHS within the inclusion dates were analyzed. There were 191 patients referred to the GP for counseling and possible genetic testing. Eighty percent of the referred patients underwent genetic testing. Twelve patients tested positive for deleterious mutations in BRCA 1 or 2. A statistically significant difference was found in the BC patients referred to the GP with respect to age, MRI usage, neoadjuvant chemotherapy, type and laterality of surgery, ALND, plastic surgery consult & reconstruction, and time from diagnosis to surgery. MRI usage in patients referred to GP was 43.5% vs. 12.7% in those not referred. Mastectomy rate in patients referred to GP was 51.3% vs. 25.5% (p<0.001) in those not referred. Bilateral mastectomy was 30.9% vs. 5.8% (p<0.001). Conclusions: We have found that patients referred to the GP have increased the use of MRI testing, which in itself has been shown to increase mastectomy rates. We also identified a trend in these patients toward bilateral mastectomy. According to our outcomes, there are multiple possible reasons for this trend, including family history, physician bias, stage at diagnosis, age and factors intrinsic to the patient. Furthermore, a multivariate analysis is needed to assess the relationship between a GR and a patient’s surgical decision.

Abstract 2760: Impact of race and age on choice of surgery in newly diagnosed breast cancer patients who tested negative for BRCA 1/2 mutation

Introduction:

The benefit of bilateral mastectomies in breast cancer patients who test negative for a deleterious BRCA mutation has not been proven. In spite of this, a significant number of women with unilateral breast cancer who test negative for BRCA mutation choose bilateral mastectomies. We aimed to evaluate the role of age and race in such decision making.

Methodology:

Records of 323 patients referred to Cancer Genetics between January 01,2012 and June 30,2014 for pre-operative genetic evaluation were analyzed. This cohort consisted of patients with newly diagnosed breast cancer who met genetic testing criteria. Patients were excluded if their surgical records were not available, they declined genetic testing, they underwent surgery prior to their test results being available or they were positive for BRCA mutation. A total of 148 patients met our inclusion criteria and were evaluated for final analysis. Statistical analysis was performed using SPSS21.

Results:

Of the 148 women with breast cancer who tested negative for a deleterious BRCA mutation, 116(78%) were Caucasian, 9(6%) were African-American, 5(3%) were Asian, 4(3%) were Arab, 3(2%) were Indian, 2(2%) were American-Indian and 1(1%) was Hispanic. The race or ethnicity could not be identified in 8(5%) patients.

A total of 47(32%) patients ultimately underwent bilateral mastectomies in this cohort. Of these, 40(27%) underwent bilateral mastectomies as their initial surgery while 7(5%) underwent bilateral mastectomies eventually after undergoing partial mastectomy or simple mastectomy initially.

There was no statistically significant difference between the mean ages of the group that underwent bilateral mastectomy (48.9 yrs) and the group that underwent partial or simple mastectomy (49.1 yrs).

All of the 8 patients with an unknown ethnicity underwent bilateral mastectomy. The rest of the mastectomies (39) were performed in Caucasian patients. None of the non-Caucasian patients underwent bilateral mastectomy. This difference was statistically significant (p&lt;0.001).

Conclusion:

Our study demonstrates that a significant proportion(32%) of BRCA negative women with breast cancer undergo bilateral mastectomies. Furthermore, Caucasian patients with BRCA negative breast cancer are more likely to choose bilateral mastectomies than non-Caucasians. However, this result has to be interpreted with caution as our sample size of non-Caucasians was small(24). Considering our catchment population, this small sample brings concerns that a significant proportion of non-Caucasian patients may not be undergoing genetic testing despite meeting criteria. We did not find a significant impact of age on choice of surgery in BRCA negative women with breast cancer. Further studies with larger sample size are needed to better understand the role of race and age in access to genetic testing and surgical decision making.

Citation Format: Siddhartha Yadav, Heidi Dreyfuss, Jennifer Fulbright, Ashley Reeves, Sarah Campian, Dana Zakalik. Impact of race and age on choice of surgery in newly diagnosed breast cancer patients who tested negative for BRCA 1/2 mutation. [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 2760. doi:10.1158/1538-7445.AM2015-2760

Timing of oral contraceptive use and the risk of breast cancer in BRCA1 mutation carriers

It is not clear if early oral contraceptive use increases the risk of breast cancer among young women with a breast cancer susceptibility gene 1 (BRCA1) mutation. Given the benefit of oral contraceptives for the prevention of ovarian cancer, estimating age-specific risk ratios for oral contraceptive use and breast cancer is important. We conducted a case-control study of 2,492 matched pairs of women with a deleterious BRCA1 mutation. Breast cancer cases and unaffected controls were matched on year of birth and country of residence. Detailed information about oral contraceptive use was collected from a routinely administered questionnaire. Conditional logistic regression was used to estimate the odds ratios (OR) and 95 % confidence intervals (CI) for the association between oral contraceptive and breast cancer, by age at first use and by age at diagnosis. Among BRCA1 mutation carriers, oral contraceptive use was significantly associated with an increased risk of breast cancer for women who started the pill prior to age 20 (OR 1.45; 95 % CI 1.20-1.75; P = 0.0001) and possibly between ages 20 and 25 as well (OR 1.19; 95 % CI 0.99-1.42; P = 0.06). The effect was limited to breast cancers diagnosed before age 40 (OR 1.40; 95 % CI 1.14-1.70; P = 0.001); the risk of early-onset breast cancer increased by 11 % with each additional year of pill use when initiated prior to age 20 (OR 1.11; 95 % CI 1.03-1.20; P = 0.008). There was no observed increase for women diagnosed at or after the age of 40 (OR 0.97; 95 % CI 0.79-1.20; P = 0.81). Oral contraceptive use before age 25 increases the risk of early-onset breast cancer among women with a BRCA1 mutation and the risk increases with duration of use. Caution should be taken when advising women with a BRCA1 mutation to take an oral contraceptive prior to age 25.

The impact of pregnancy on breast cancer survival in women who carry a BRCA1 or BRCA2 mutation

Physicians are often approached by young women with a BRCA mutation and a recent history of breast cancer who wish to have a baby. They wish to know if pregnancy impacts upon their future risks of cancer recurrence and survival. To date, there is little information on the survival experience of women who carry a mutation in one of the BRCA genes and who become pregnant. From an international multi-center cohort study of 12,084 women with a BRCA1 or BRCA2 mutation, we identified 128 case subjects who were diagnosed with breast cancer while pregnant or who became pregnant after a diagnosis of breast cancer. These women were age-matched to 269 mutation carriers with breast cancer who did not become pregnant (controls). Subjects were followed from the date of breast cancer diagnosis until the date of last follow-up or death from breast cancer. The Kaplan-Meier method was used to estimate 15-year survival rates. The hazard ratio for survival associated with pregnancy was calculated using a left-truncated Cox proportional hazard model, adjusting for other prognostic factors. Among women who were diagnosed with breast cancer when pregnant or who became pregnant thereafter, the 15-year survival rate was 91.5 %, compared to a survival of 88.6 % for women who did not become pregnant (adjusted hazard ratio = 0.76; 95 % CI 0.31-1.91; p = 0.56). Pregnancy concurrent with or after a diagnosis of breast cancer does not appear to adversely affect survival among BRCA1/2 mutation carriers.

Assessment of cancer screening practices after BRCA testing in Michigan

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Background: Women who harbor BRCA1/2 mutations are at increased risk for breast and ovarian cancer and are advised to undergo high risk surveillance and/or preventative surgery. The compliance with screening guidelines in these women is not well known. This study aims to evaluate the uptake and screening practices of women with known deleterious BRCA mutations and BRCA true negatives who received genetic counseling in the state of Michigan. Methods: A telephone survey coordinated by the Michigan Department of Community Health was conducted on pts seen at 8 genetics clinics between 10/07 to 10/09. Each center was staffed by board certified genetics professionals who provided pre and post-test genetic counseling. Pts who were found to carry a deleterious BRCA mutation, or to be negative for a known familial mutation, were queried regarding adherence to NCCN guidelines. Results: 138 of 253 (55%) pts responded to the phone survey, with an elapsed time of 1.7 to 4.6 years from post-test counseling session. Among BRCA mutation carriers over age 25 years with no cancer history or mastectomy, 11 of 21 pts (52%) adhered to MRI screening guidelines, 3 pts (14%) reported two MRIs, and 7 (33%) pts had no MRI screening in the preceding year. 18 of 21 pts (86%) reported having a screening mammogram in the preceding year and the remaining 3 had two or more. 8 of 20 (40%) pts had two clinical breast exams. Of the women who had breast cancer and no mastectomy, 5 of 9 (56%) pts did not have MRI screening. Of the BRCA true negatives with no cancer history, CA-125 or transvaginal ultrasound was performed in 7 (19%) and 8 (20%) of 37 pts, respectively. Conclusions: This study reveals sub-optional compliance with screening guidelines in women who were identified to be carriers of BRCA mutations or those who were true negatives, despite pre and post-test genetic counseling and communication of established management guidelines. Some recommended screening measures were under-utilized in BRCA mutation carriers, and some were over-utilized in the true negatives. Additional interventions are needed to improve adherence to evidence-based screening guidelines aimed at promoting early detection, with an emphasis on appropriate utilization of limited healthcare resources.

Unique genetic characteristics of BRCA mutation carriers in a cohort of Arab American women

1541

Background: Worldwide ethnic variations in the distribution of BRCA1 and BRCA2 mutations of breast cancer patients have been recently recognized. This has led to investigations of the epidemiology, genetics and clinical characteristics of BRCA positive individuals within specific populations. This study aims to describe the findings of BRCA genetic testing in a cohort of Arab American women. Methods: A total of 73 women of Arab ancestry were evaluated in the Beaumont Cancer Genetics Program from Jan 2008 to Jan 2013. Criteria for genetic testing included a personal or family history suggestive of Hereditary Breast and Ovarian Cancer Syndrome (HBOC). Patients underwent comprehensive genetic counseling, followed by full sequence analysis for germline mutations in BRCA1 and BRCA2. Results: 63 women of Arab ancestry underwent genetic testing for BRCA1 and BRCA2. 13 (21%) patients were found to be mutation carriers, of whom 10 (16%) of the 63 had deleterious mutations (7 in BRCA2, and 3 in BRCA1), and 3 (5%) had variants of undetermined significance (VUS) in BRCA2. Of the 10 patients with deleterious mutations, 4 (40%) unrelated individuals had the same mutation, 5804del4, in exon 11 of BRCA2. The remaining patients had deleterious mutations in exon 2, exon 20, and exon 13 of BRCA2; one patient had a BRCA1 and BRCA2 mutation (exon 18). 7 of 10 patients with deleterious mutations had a cancer diagnosis, of which 5 had breast cancer, 1 had ovarian cancer, 1 had pancreatic cancer, and 3 were unaffected. Conclusions: This study demonstrates that BRCA mutations (predominantly in BRCA2) were seen in a significant proportion of Arab American women undergoing genetic testing for HBOC. A mutation in BRCA2, 5804del4, was seen in nearly half (4/10) of the carriers of deleterious mutations. This mutation, in exon 11, has not previously been associated with Arab ethnicity and may represent a founder mutation. Knowledge of the genetic spectrum, frequency, and clinical characteristics of BRCA mutation carriers will lead to greater understanding of hereditary cancer in Arab American women.

Oophorectomy after menopause and the risk of breast cancer in BRCA1 and BRCA2 mutation carriers

BACKGROUND

To evaluate the effect of the cumulative number of ovulatory cycles and its contributing components on the risk of breast cancer among BRCA mutation carriers.

METHODS

We conducted a matched case-control study on 2,854 pairs of women with a BRCA1 or BRCA2 mutation. Conditional logistic regression was used to estimate the association between the number of ovulatory cycles and various exposures and the risk of breast cancer. Information from a subset of these women enrolled in a prospective cohort study was used to calculate age-specific breast cancer rates.

RESULTS

The annual risk of breast cancer decreased with the number of ovulatory cycles experienced (ρ = -0.69; P = 0.03). Age at menarche and duration of breastfeeding were inversely related with risk of breast cancer among BRCA1 (P(trend) < 0.0001) but not among BRCA2 (P(trend) ≥ 0.28) mutation carriers. The reduction in breast cancer risk associated with surgical menopause [OR, 0.52; 95% confidence interval (CI), 0.40-0.66; P(trend) < 0.0001] was greater than that associated with natural menopause (OR, 0.81; 95% CI, 0.62-1.07; P(trend) = 0.14). There was a highly significant reduction in breast cancer risk among women who had an oophorectomy after natural menopause (OR, 0.13; 95% CI, 0.02-0.54; P = 0.006).

CONCLUSIONS

These data challenge the hypothesis that breast cancer risk can be predicted by the lifetime number of ovulatory cycles in women with a BRCA mutation. Both pre- and postmenopausal oophorectomy protect against breast cancer.

IMPACT

Understanding the basis for the protective effect of oophorectomy has important implications for chemoprevention.

How we treat tumor lysis syndrome

Tumor lysis syndrome (TLS) is an oncology emergency that occurs as a result of rapid tumor cell breakdown and the consequent release of massive amounts of intracellular contents, including potassium, phosphate, and uric acid, into the systemic circulation. These metabolic disturbances lead to life-threatening conditions and may cause sudden death if not treated. TLS commonly occurs following initiation of cytotoxic treatment in patients with high-grade lymphomas or acute lymphoblastic leukemia. Spontaneous cases involving both solid and hematologic tumors have also been reported. Rarely, TLS occurs following treatment with irradiation, corticosteroids, hormonal therapy, or biologic therapy. It is necessary to identify patients at risk for TLS early in order to initiate preventive measures. In the event that preventive measures fail, the clinical parameters and signs of TLS must be understood and recognized so that treatment can begin as soon as possible, as this condition is a significant cause of morbidity and mortality.

Venous limb gangrene and fatal hemorrhage: adverse consequences of HIT "overdiagnosis" in a patient with antiphospholipid syndrome

This unfortunate patient case highlights the problems with "overdiagnosis" of HIT. Despite "positive" tests for HIT antibodies, the low pretest probability for HIT and the known propensity of patients with APS to yield false-positive HIT antibody results suggests that the patient did not have a true diagnosis of HIT. Moreover, the early administration of warfarin and the choice of argatroban for parenteral anticoagulation when monitoring was hindered by a prolonged baseline aPTT likely play a key factor in the progression of UE DVT to VLG. Ironically, the problems of anticoagulant monitoring posed by the prolonged baseline aPTT likely contributed to the subsequent overanticoagulation and fatal pulmonary hemorrhage. With benefit of hindsight, avoiding the temptation to test for HIT in a low pretest probability situation, and treatment with either heparin using anti-factor Xa monitoring or with non-aPTT-monitored therapy such as LMWH or fondaparinux would likely have resulted in a more favorable clinical course.

Abstract P2-10-03: Impact of BRCA 1 and 2 Gene Mutation Testing on Surgical Decision-Making in Newly Diagnosed Breast Cancer Patients

BACKGROUND: Breast cancer patients with BRCA 1 or 2 gene mutations demonstrate a high lifetime incidence of a second breast cancer in the contralateral breast. These patients may benefit from a bilateral mastectomy (BLM) with an intent of risk reduction. If provided in the right window between cancer diagnosis and definitive treatment, genetic cancer risk assessment would aid high-risk patients in making an informed decision with respect to planning appropriate surgery.

OBJECTIVE: The purpose of this study is to assess the feasibility of BRCA 1 and BRCA 2 gene mutation testing in the pre-operative setting and to determine whether test results altered final surgical decision. METHODS: Newly diagnosed breast cancer patients referred to the cancer genetics clinic between April 2009 to March 2010 were identified. All patients were sent for genetic cancer risk assessment due to the presence of clinical features suggestive of hereditary breast cancer based on current guidelines. A retrospective chart review of the patients was performed. RESULTS: 81 patients were identified. 6 patients were excluded as they went on to have surgery in a different hospital and were lost to follow up. 3 patients did not meet criteria for genetic testing. 1 patient was excluded as she was scheduled for a BLM prior to being seen in our clinic, and 1 patient was receiving neoadjuvant chemotherapy and hadn't had surgery at the time of data collection. Of the remaining 70 patients, the mean age was 48 years (29-74 years) with 81% being of caucasian race and 11% having Ashkenazi-Jewish ethnicity. 30% had two or more first degree and 68% had two or more second degree relatives with cancer. 29% had a first degree relative who had died of cancer. 74% had a diagnosis of invasive breast cancer, where as 26% only had in-situ disease. Further, 21% had grade 1, 37% with grade 2 and rest with grade 3 tumors. 81% tested negative for BRCA gene mutations, 9% were positive for either BRCA 1/2, 6% had variants of uncertain significance(VUS) and 4% didn't undergo genetic testing for various reasons. It took an average of 9.3 days (4-31 days) to obtain results. 54% of women aged 40 years or younger chose BLM versus 25% of women over 40 (p=0.015). 6.7% of women with low grade breast cancer underwent BLM versus 54% with moderate grade and 34% with high grade cancer (p=0.0098). Based on the BRCA results, 83% of BRCA positive women chose BLM versus 33% of BRCA negative (true negative and VUS) patients (p=0.024). A negative result had a greater influence in favor of a unilateral surgery in 67% of BRCA negative patients. In contrast, majority of women who underwent BLM were not influenced solely by their gene test results.

CONCLUSIONS: Amongst newly diagnosed breast cancer patients, genetic testing for hereditary breast and/or ovarian cancer syndromes can influence surgical decision in a risk-appropriate way. Our results show that genetic cancer risk assessment can be effectively incorporated in newly diagnosed breast cancer patients and can help guide the decision about the optimal surgery without a significant delay. A negative BRCA gene result seemed to help patients reach a decision favoring unilateral surgery.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-10-03.