Mutations In Breast Cancer Susceptibility Genes Research Articles

BRCA1/2 Mutations and Breast/Ovarian Cancer Risk: A New Insights Review.

Breast and ovarian cancers are significant global health concerns, and understanding their genetic underpinnings is essential for effective prevention and cure. This narrative review provides a comprehensive analysis of studies conducted between 1994 and June 2024, focusing on the link between specific mutations in the breast cancer susceptibility gene 1 (BRCA1) and breast cancer susceptibility gene 2 (BRCA2) and the associated risks of both breast and ovarian cancers. It encompasses the findings of various works, including observational studies and molecular profiling analyses. Conducted on large international cohorts, these studies present compelling evidence of the relationship between different BRCA1 and BRCA2 mutations and the varying risks of breast and ovarian cancer. Furthermore, this review highlights the significance of nonsense-mediated decay mutations and their impact on cancer risk, particularly concerning the age of breast cancer onset. The implications of these findings are far-reaching, offering valuable information for risk assessment and decision-making in managing individuals who carry BRCA1 or BRCA2 mutations. The molecular subtyping profile BluePrint is discussed as a potential tool for enhancing clinical care by aiding the selection of appropriate treatment options, such as endocrine therapy or chemotherapy, based on the tumor's molecular characteristics. In conclusion, we establish a robust link between specific BRCA1 and BRCA2 gene mutations and increased susceptibility to breast and ovarian cancers. These mutations impact cancer onset age and severity, underscoring the need for targeted testing and screening. The current study enhances cancer detection, prevention, and cure strategies.

Phase 1b study to assess the safety, tolerability, and clinical activity of pamiparib in combination with temozolomide in patients with locally advanced or metastatic solid tumors.

Pamiparib is a potent, selective, poly (ADP-ribose) polymerase 1/2 inhibitor that demonstrates synthetic lethality in cells with breast cancer susceptibility gene mutations or other homologous recombination deficiency. This two-stage phase 1b study (NCT03150810) assessed pamiparib in combination with temozolomide (TMZ) in adult patients with histologically confirmed locally advanced and metastatic solid tumors. Oral pamiparib 60 mg was administered twice daily. During the dose-escalation stage, increasing doses of TMZ (40-120 mg once daily pulsed or 20-40 mg once daily continuous) were administered to determine the recommended dose to be administered in the dose-expansion stage. The primary objectives were to determine safety and tolerability, maximum tolerated/administered dose, recommended phase 2 dose and schedule, and antitumor activity of pamiparib in combination with TMZ. Pharmacokinetics of pamiparib and TMZ and biomarkers were also assessed. Across stages, 139 patients were treated (dose escalation, n = 66; dose expansion, n = 73). The maximum tolerated dose of TMZ, which was administered during dose expansion, was 7-day pulsed 60 mg once daily. The most common treatment-emergent adverse events (TEAEs) were anemia (dose escalation, 56.1%; dose expansion, 63.0%), nausea (dose escalation, 54.5%; dose expansion, 49.3%), and fatigue (dose escalation, 48.5%; dose expansion, 47.9%). In the dose-escalation stage, four patients experienced dose-limiting toxicities (three neutropenia and one neutrophil count decreased). No TEAEs considered to be related to study drug treatment resulted in death. Antitumor activity was modest, indicated by confirmed overall response rate (dose escalation, 13.8%; dose expansion, 11.6%), median progression-free survival (3.7 and 2.8 months), and median overall survival (10.5 and 9.2 months). Administration of combination therapy did not notably impact pamiparib or TMZ pharmacokinetics. Pamiparib in combination with TMZ had a manageable safety profile. Further investigation of the efficacy of this combination in tumor types with specific DNA damage repair deficiencies is warranted.

Real-world Study on the Effect of PARPi as Maintenance Therapy on Platinum Sensitivity after First- and Second-line Chemotherapy in Patients with Recurrent High-grade Serous Epithelial Ovarian Cancer.

This study investigated the effect of poly(ADP-ribose) polymerase inhibitors (PARPi) as maintenance therapy after first- and second-line chemotherapy on platinum sensitivity in patients with recurrent high-grade serous epithelial ovarian cancer (rHGSOC). This study retrospectively analyzed 172 patients with rHGSOC treated at Zhejiang Cancer Hospital and Jiaxing Maternity and Child Health Care Hospital between January 2017 and December 2021. The 1st-PARPi group comprised patients who received a PARPi as maintenance therapy after first-line chemotherapy (n=23), and the 1st-control group comprised those who did not (n = 105). Similarly, the 2nd-PARPi group comprised patients not given a PARPi in their first-line treatment (n = 30), and the 2nd-control group comprised those who were given a PARPi (n = 89). Among the 23 patients in the 1st-PARPi group and the 105 patients in the 1st-control group, nine and 99 were platinum-sensitive, and 14 and six were platinum-resistant, respectively (hazard ratio [HR]: 14.46, P < 0.0001). Among the 30 patients in the 2nd-PARPi group and 89 patients in the 2nd-control group, 10 and 71 were platinum-sensitive, and 20 and 18 were platinumresistant, respectively (HR: 4.37, P < 0.0001). Age, stage, residual tumor, the courses of platinumbased chemotherapy, and breast cancer susceptibility gene mutations were not associated with platinum sensitivity when using a PARPi as maintenance therapy after first- and second-line chemotherapy. Patients with rHGSOC using a PARPi were more likely to be platinum-sensitive and develop platinum resistance independent of PARPi duration. Care should be taken when using a PARPi as maintenance therapy after first- and second-line chemotherapy.

Hereditary Breast and Ovarian Cancer Syndromes

Women who inherit a mutation in the BRCA1 or BRCA2 gene are much more likely to develop breast and ovarian cancer. A woman’s specific risk depends on many factors including her age, whether she has a BRCA1 or BRCA2 mutation, and her medical and family history. Most women with breast or ovarian cancer have a sporadic cancer. The majority of women with inherited breast and/or ovarian cancers carry a pathogenic variant (ie, deleterious or harmful mutation) in breast cancer susceptibility gene 1 (BRCA1) or breast cancer susceptibility gene 2 (BRCA2), some hereditary breast cancers are due to other rare hereditary syndromes, such as Li-Fraumeni and Cowden syndromes, which are associated with pathogenic variants in the tumor protein p53 (TP53) and phosphatase and tensin homolog tumor suppressor (PTEN) genes, respectively. Pathogenic variants in other genes also confer a heightened risk of breast and/or ovarian cancer.hereditary breast and ovarian cancer syndromes associated with genes other than BRCA1/2.

Abstract B042: A screen to identify modifiers of BRCA1 protein level for cancer prevention and treatment

Abstract The breast cancer susceptibility gene 1 (BRCA1) is a nuclear phosphoprotein involved in DNA double-strand break (DSB) repair and maintenance of genome stability. A single BRCA1 mutation leads to reduced levels of functional BRCA1 protein, such that DSB repair is compromised. It has been proposed that BRCA1 is a haploinsufficient tumor suppressor gene in some contexts, which when lost accelerates the mutation rate of other critical genes thus increasing neoplastic transformation. BRCA1 expression levels are modified through exogenous exposures, and modulating BRCA1 expression may alter tumour onset, progression, and treatment options. We hypothesize that compounds that increase BRCA1 expression and function may prevent the outgrowth of BRCA1-associated breast cancer. By contrast, compounds that reduce BRCA1 protein level could be used as combination therapries in conjunction with poly-ADP ribose polymerase (PARP) inhibitors. To achieve these goals, we generated BRCA1-reporter cell lines. Using CRISPR-assisted genome editing, we endogenously tagged the BRCA1 protein with HiBiT, an 11 amino acid luminescent tag. BRCA1-targeting was verified by sequencing and immunoblotting, and functional validation was performed with known modulators of BRCA1 expression. Our tests confirmed that HiBiT-tagging allows for sensitive measurement of BRCA1 protein levels, therefore permitting screenability. BRCA1-reporter cells were subsequently used to conduct a pilot screen (64 epigenetic-modifying drugs) and a high-content screen (6,000 compounds). We identified several compounds that modified BRCA1 protein expression (B-score &amp;gt;3*SD). The epigenetic drug library yielded five repressors and two activators, and the high-content screen identified 163 repressors and 12 activators. Validation studies have confirmed that the activator drug, aloxistatin can elevate BRCA1-HiBiT levels in a dose-dependent manner. Additionally, aloxistatin treatment increased BRCA1 expression and function in a panel of breast cells. We have also assessed 9 down-regulators of BRCA1 from the pilot and high-content screens. Each of these nine compounds reduced the expression of BRCA1 protein and synergized with the PARP inhibitor olaparib to inhibit cancer cell growth. Collectively, our ongoing studies suggest that BRCA1 activation may reduce cancer phenotypes and BRCA1 repression can sensitize breast cancer cells to PARP-inhibition and other chemotherapies. Overall, using our reporter cell lines we have identified a number of unique compounds that effectively modify BRCA1 expression and function that may have utility in the treatment and prevention of BRCA1-associated cancers. Citation Format: Erin Sellars, Margarita Savguira, Joanne Kotsopoulos, Leonardo Salmena. A screen to identify modifiers of BRCA1 protein level for cancer prevention and treatment [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B042.

Oral contraceptives and risk of breast cancer and ovarian cancer in women with a BRCA1 or BRCA2 mutation: a meta-analysis of observational studies.

It remains inconclusive whether the use of oral contraceptives (OCs) alters the risks of breast or ovarian cancer in women with a breast cancer susceptibility gene 1 (BRCA1) or breast cancer susceptibility gene 2 (BRCA2) mutation. We investigated the association between OC use and the risks of breast or ovarian cancer in this group by using a meta-analysis. PubMed and EMBASE were searched using keywords until February 2021 to identify relevant studies that evaluated the association between OC ever use and the risks of breast or ovarian cancer in women with a BRCA1 or BRCA2 mutation. Twelve studies for breast cancer and eight studies for ovarian cancer were identified. In the random-effects meta-analysis, the ever use of OCs was significantly associated with an increased risk of breast cancer [odds ratio (OR), relative risk (RR) or hazard ratio (HR) = 1.24; 95% confidence interval (CI) 1.08-1.41] and a decreased risk of ovarian cancer (OR/RR/HR = 0.53, 95% CI 0.41-0.67). Consistent findings were observed when BRCA1 and BRCA2 mutation carriers were analyzed separately. The increased risk of breast cancer was observed only in the long-term (>5 years) users of OCs, while the decreased risk of ovarian cancer was observed regardless of the duration of OC use. The current study suggests that the ever use of OCs in BRCA mutation carriers is significantly associated with an increased risk of breast cancer and a decreased risk of ovarian cancer. Therefore, the use of OCs as chemoprevention of ovarian cancer should be cautious in BRCA mutation carriers.

Systematic review of family studies of heritable breast cancer in Africa.

e22508 Background: The incidence of breast cancer (BC) in Africa (40.4 per 100,000) is 49% that of Europe and North America (81.9 per 100,000) but the mortality rate is 42% higher (19.4 versus 13.7 per 100,000). The high mortality is due to lack of screening. However, more targeted screening based on genomic risks are also missed because of stigmatization, poor family history, and limited information on BC susceptibility gene mutations. Internationally based family members are influencing cultural attitudes to BC in Africa leading to reduced stigmatization, increased better family history and uptake of genomic screening. Family-based studies of BC in Africa would provide useful information on prevalence of mutations that can inform genomic screening panels. We conducted systemic review of all family-based studies of BC in Africa to document state of the art, identify barriers and facilitators of this research method and methods of advancing the science. Methods: Using a comprehensive research strategy, we reviewed articles indexed in PubMed and African Journals Online (AJOL) to identify studies of familial BC in Africa. Specifically, we searched for family-based, study design papers on BC in each country in Africa using the following keywords: breast cancer, family-studies, hereditary, genetic, gene, mutations, and Africa. We excluded case-control, and registry studies, and clinical trials. We extracted relevant information from each study using standardized criteria: number of first- and second-degree relatives affected by BC, mutations, genetic variations, and polymorphisms. Results: A total of 12 out of 727 studies met our inclusion criteria. 80% of these studies were published after the year 2010. There were 9 publications from North Africa evaluating 191 families in total. One study reported novel breast cancer candidate genes: MMS19, DNAH3, POLK and KATB6 and nine publications investigated the mutation spectrum of BRCA genes. One publication from West Africa and one publication from Southern Africa included 1 and 219 families, respectively. All the studies done in these two regions reported targeted genomic screening for only BRCA genes. No study was done in Central and East Africa. Conclusions: There is paucity of family-based studies of breast cancer in Africa. Given the high level of heterogeneity in African genomes, these types of studies may be needed to identify high penetrance, germline mutations to better understand hereditary BC risk and ultimately develop a multigene panel testing to for diagnosis of heritable BC in this population.

PARP inhibitors in breast and ovarian cancer with BRCA mutations: a meta-analysis of survival.

Objective: To evaluate the efficacy of poly ADP ribose polymerase (PARP) inhibitors (PARPis) in breast and ovarian cancer with BRCA (BReast CAncer susceptibility gene) mutation (BRCAm).Methods: We conducted a meta-analysis of randomized controlled, phase II or III trials by searching of electronic databases from inception to September 1, 2020. The efficacy of PARPis measured by hazard ratios (HRs) and 95% confidence intervals (95% CIs) for progression free survival (PFS) and overall survival (OS) of patients.Results: By addition of PARPis to conventional therapy, breast or ovarian cancer patients carrying BRCAm significantly benefited PFS (breast cancer: HR 0.64, 95% CI=0.55-0.75, P<0.001; ovarian cancer: HR 0.33, 95% CI=0.27-0.42, P<0.001), but OS of patients did not increase significantly in these two cancer types (breast cancer: HR 0.87, 95% CI=0.76-1.01, P=0.065; ovarian cancer: HR 0.78, 95% CI=0.61-1.01, P=0.058). For ovarian cancer patients carrying BRCAm, the use of therapy with PARPis yielded longer PFS at the stage of newly diagnosed than the stage of recurrence (22.5 months vs 9.6 months).Conclusion: PARPis were beneficial to all with BRCAm, but they were "most" beneficial to the ovarian cancer subset when administered early after diagnosis, rather than after recurrence.

Design and Synthesis of BRCA1 (856-871) Analogous and their Interactions with RAD51 (158-180)

Breast cancer susceptibility gene 1 (BRCA1) is an important tumor suppressor gene in the human which associated with a variety of tumor suppressor genes to inhibit the growth of malignant tumors. Breast cancer is closely related to BRCA1 mutations in humans. Four BRCA1 (856-871) mutants were screened that can interact well with RAD51 (158-180) using computer to simulate mutations at Y 856, R 866 and Q 867. These mutants were synthesized by using Fmoc solid-phase synthesis, and purified by liquid chromatography. According to the results of fluorescence spectroscopy, R866W has the strongest binding ability for the above peptides and RAD51 (158-180). Based on the circular dichroism spectrum results, the sequence of the interaction ability of the above peptides on the secondary structure of RAD51 (158-180) is Y856P, Q867C > Y856P, R866W ≈ R866W > Y856P > BRCA1. All the spectral results show that R866W have the strongest interaction ability with RAD51(158-180).

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

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

Abstract P6-08-07: Polygenic breast cancer risk modification in carriers of high and intermediate risk gene mutations

Abstract Background: The incorporation of polygenic scores into breast cancer risk assessment models has led to improved risk management for women of European ancestry. However, few studies have examined the extent to which polygenic scores modify risk for carriers of breast cancer susceptibility gene mutations. Current literature suggests that a 77-SNP polygenic score developed from large, mainly non-carrier general population studies can stratify breast cancer risk for carriers of the CHEK2 founder mutation 1100delC with the same effect size observed for non-carriers. Consequently, several groups have modified risk estimates for carriers of other pathogenic variants by applying published effect estimates from non-carriers. In a recent study, a similar 88-SNP polygenic score showed reduced effectiveness in BRCA1 and BRCA2 carriers compared to non-carriers. This highlights the need for more information on polygenic score performance among women who carry pathogenic variants in ATM or PALB2, or in CHEK2 other than the 1100delC founder mutation. We previously described an 86-SNP polygenic residual risk score (RRS) that characterizes genetic risk which is not due to high- or moderate-penetrance breast cancer gene mutations. Here, we present pre-specified independent validation of the RRS for BRCA1, BRCA2, CHEK2, ATM and PALB2 carriers.Methods: This IRB-approved study included 152,172 women of European ancestry who were tested clinically for hereditary cancer risk with a multi-gene panel. The RRS was evaluated separately for carriers of BRCA1 (N=2,249), BRCA2 (N=2,638), CHEK2 (N=2,564), ATM (N=1,445) and PALB2 (N=906), and for mutation-free women (N=141,160). Clinical information was obtained from test requisition forms. Multivariable logistic regression was used to examine the association of RRS with invasive breast cancer after accounting for age and family cancer history. Effect sizes, expressed as standardized odds ratios (ORs) with 95% confidence intervals (CIs), were assessed for carriers of each gene and for non-carriers. Results: RRS was strongly associated with breast cancer risk in each of the BRCA1, BRCA2, CHEK2, ATM and PALB2 carrier populations (p&amp;lt;10−4). Risk modification in CHEK2 carriers (OR 1.49; CI 1.36-1.64) was consistent with that observed in non-carriers (OR 1.47; CI 1.45-1.49). CHEK2 carriers in the highest RRS quintile had approximately 1.7-fold higher risk than the middle quintile (OR 1.67; CI 1.26 - 2.20), and the lowest quintile had risk lowered by factor of 0.59 (OR 0.59; CI 0.44 - 0.80). We observed reduced modification similar to existing literature for carriers of BRCA1 (OR 1.20; CI 1.10-1.32) and BRCA2 (OR 1.23; CI 1.12-1.34). Odds ratios for ATM (1.37; CI 1.21-1.55) and PALB2 (1.34; CI 1.16-1.55) had wide confidence intervals that overlapped those for the other carrier populations. Discussion: The RRS significantly modifies risk for carriers of BRCA1, BRCA2, CHEK2, ATM and PALB2 mutations albeit with apparently different effect sizes. These results indicate that risk estimates employing polygenic scores may need to be derived separately for each gene. Given the modest effect on BRCA1 and BRCA2 risk and the substantial risks conferred by these genes even with lower RRS, the clinical implications of polygenic modification in this setting are yet to be determined. In CHEK2 carriers, we observed strong polygenic modification similar to that achieved for non-carriers. For ATM and PALB2, larger studies are needed to refine polygenic effect size estimates. Comprehensive risk assessment combining RRS with family cancer history and other risk factors has potential to refine risk estimates and facilitate decision-making for women with mutations in moderate penetrance genes. Citation Format: Shannon Gallagher, Elisha Hughes, Susanne Wagner, Placede Tshiaba, Eric Rosenthal, Benjamin B. Roa, Allison Kurian, Susan Domchek, Judy Garber, Johnathan M. Lancaster, Jeffrey Weitzel, Alexander Gutin, Jerry S. Lanchbury, Mark Robson. Polygenic breast cancer risk modification in carriers of high and intermediate risk gene mutations [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-08-07.

Incidental Serous Tubal Intraepithelial Carcinoma Detected by a Surgery for Ectopic Pregnancy

Serous tubal intraepithelial carcinoma is a putative precursor of high-grade serous carcinoma, which is the most common histological type of ovarian or pelvic peritoneal cancer. Serous tubal intraepithelial carcinoma is commonly found in patients with breast cancer susceptibility gene mutations who undergo risk-reducing salpingo-oophorectomy. Incidental serous tubal intraepithelial carcinoma found by a non-prophylactic surgery is rare. A 33-year-old woman referred to our hospital for a diagnosis of ectopic pregnancy. She underwent a laparoscopic right salpingectomy. Pathologically, ectopic pregnancy in the ampulla of the right fallopian tube was confirmed and serous tubal intraepithelial carcinoma was observed in the fallopian tube. Subsequently, she underwent a laparoscopic hysterectomy, bilateral oophorectomy, and left salpingectomy as additional treatment. She has experienced no recurrence thus far for 37 months since the surgery.

Abstract P1-09-13: A real world evidence study of BRCA mutations and survival in HER2-negative breast cancer

Abstract Background: Limited data exist on the natural history (treated with standard of care) of metastatic breast cancer (mBC) characterized by germline breast cancer susceptibility gene mutations (gBRCAm). Real-world data examining survival for patients with gBRCAm mBC, overall and separated into gBRCA1m and gBRCA2m, compared to gBRCA wild type (wt) mBC, can help to clarify the prognostic outlook associated with the gBRCA mutation. Methods: Adults with human epidermal growth factor receptor 2 negative (HER2-) mBC diagnosed from January 2013 – August 2017 were retrospectively selected from the Flatiron Health Oncology electronic medical record database. Patients were classified as having gBRCA1m, gBRCA2m, or gBRCAwt disease. Those who did not receive the genetic testing or who had equivocal results were classified as gBRCA unknown. Overall survival (OS) was calculated from first diagnosis of mBC, as well as from the start of first- and second-line therapy for metastatic disease. Lines of therapy included both hormonal and systemic therapies. Kaplan-Meier analyses provided median OS with 95% confidence interval (CI). Unadjusted log-rank tests compared OS between gBRCA1m and gBRCA2m, and between overall gBRCAm and gBRCAwt. Results: Of 8,080 patients selected, mean age at first mBC diagnosis was 64 years, 98.7% were female, and 82.0% had evidence of hormone receptor positive disease. gBRCA status was known for 1,852 (22.9%) of patients, of whom 89 (4.8%) had gBRCA1m, 152 (8.2%) had gBRCA2m, and 8 (0.4%) had both gBRCA mutations. Patients with known gBRCA status were younger, with mean ages of 52 years for gBRCAm, 55 years for gBRCAwt, and 67 years for gBRCA unknown. Hormone receptor positive disease was less common among those with known gBRCA status (71.9%, 77.2%, and 83.6% for gBRCAm, gBRCAwt, and gBRCA unknown, respectively). Median (95% CI) OS from mBC diagnosis was 22 (14 - 26) months for gBRCA1m and 30 (27 - 37) months for gBRCA2m (p = 0.01), though numbers were quite small by the median timepoint. Overall gBRCAm disease was associated with median survival of 28 (25 - 32) months, compared to 32 (30 - 35) months for gBRCAwt (p = 0.07); survival was similar between groups for the first 24 months but declined thereafter in the gBRCAm group. Similar patterns were observed for OS after the start of first- and second-line therapy, although no comparisons were significant. Further analyses will present adjusted results and comparisons with outcomes for the patients with gBRCA unknown. Conclusions: This real-world study of patients receiving care in largely community oncology clinics suggests that survival after diagnosis of mBC is reduced in patients with gBRCA1m compared to gBRCA2m disease and may be reduced in gBRCAm mBC overall. Effective treatments targeted for the gBRCAm subtypes of mBC appear to be needed. Citation Format: Dalvi T, McLaurin K, Briceno J, Nordstrom B, Bennett J, Hettle R, Murphy B, Collins J, McCutcheon S. A real world evidence study of BRCA mutations and survival in HER2-negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-09-13.

Efficacy and safety of niraparib as maintenance treatment in older patients (≥ 70 years) with recurrent ovarian cancer: Results from the ENGOT-OV16/NOVA trial

ObjectiveTo analyze the safety and efficacy of niraparib in patients aged ≥70 years with recurrent ovarian cancer in the ENGOT-OV16/NOVA trial. MethodsThe trial enrolled 2 independent cohorts with histologically diagnosed recurrent ovarian, fallopian tube, or peritoneal cancer who responded to platinum rechallenge, on the basis of germline breast cancer susceptibility gene mutation (gBRCAmut) status. Patients were randomized 2:1 to receive niraparib (300 mg) or placebo once daily until disease progression. The primary endpoint was progression-free survival (PFS) by blinded independent central review. Adverse events (AEs) of special interest were based on the known safety profile of poly(ADP-ribose) polymerase inhibitors. ResultsPatients aged ≥70 years in the gBRCAmut cohort receiving niraparib (n = 14) had not yet reached a median PFS compared with a median PFS of 3.7 months for the same age group in the placebo arm (hazard ratio [HR], 0.09 [95% confidence interval (CI), 0.01 to 0.73]). Non-gBRCAmut patients aged ≥70 years receiving niraparib (n = 47) had a median PFS of 11.3 months compared with 3.8 months in the placebo arm (HR, 0.35 [95% CI, 0.18 to 0.71]). Median duration of follow-up in the niraparib arm was 17.3 months in patients ≥70 years and 17.2 months in patients <70 years. Frequency, severity of AEs, and dose reductions in the niraparib arm were similar in patients aged <70 and ≥ 70 years population. The most common grade ≥ 3 AEs in patients ≥70 years were hematologic: thrombocytopenia event (34.4%), anemia event (13.1%), and neutropenia event (16.4%). ConclusionsFor patients ≥70 years of age receiving niraparib as maintenance treatment in the ENGOT-OV16/NOVA trial, PFS benefits and incidence of any grade or serious treatment-emergent AEs were comparable to results in the younger population. Use of niraparib should be considered in this population.

NGS-Based BRCA1, BRCA2, and PALB2 Mutation Testing in Iranian Population With Breast Cancer

Background: Identification of individuals who have a pathogenic mutation in breast cancer susceptibility genes is an important step to take advantage of genetic counseling, screening, and potentially life-saving prevention strategies. Based on the National Comprehensive Cancer Network (NCCN) guideline, genetic testing is deemed suitable for breast cancer patients with young age at onset, positive family history of cancers, male breast cancer, or diagnosis with a multifocal or triple negative breast cancer. Aim: Since, it is not known what proportion of breast cancers in Iran is hereditary and related to mutations in BRCA1/2 and PALB2 genes, therefore, we screened these 3 genes in multiethnic Iranian population to determine the spectrum of the breast cancer susceptibility gene mutations and to further assess the predictive value of the hereditary breast cancer risk criteria for genetic testing. Methods: Next generation sequencing (NGS) was conducted on a population consisted of 299 and 125 breast cancer patients, with and without hereditary cancer risk criteria for genetic testing, respectively. Results: Pathogenic mutation rate was 10.36% in patients with hereditary criteria for breast cancer vs 1.6% in no criteria group ( P = 0.002). All the patients who only met the young age at onset (&lt;40) criterion tested negative for a gene mutation. This is while patients who had only 1 hereditary criterion (OR: 5.48, 95% CI: 1.09, 52.90, P = 0.017) and patients with multiple hereditary criteria (OR: 22.5, 95% CI: 5.19, 201.31, P &lt; 0.0001) had a significantly higher probability of finding a mutation compared with no risk-criteria group. Conclusion: The first application of NGS on Iranian breast cancer population added to the cumulative evidence that BRCA1/2 mutations are seen commonly among Iranian breast cancer patients especially those with hereditary breast cancer criteria and indicated that PALB2 should be concerned in hereditary breast cancer screening alongside BRCA1/2. Investigating the predictive potential of hereditary breast cancer risk criteria our results suggest that offering genetic testing to women with early age at onset of &lt;40 with no other hereditary criteria, may not be cost effective and should be considered for optimization of genetic counseling and genetic testing of the Iranian population.

Germline breast cancer susceptibility gene mutations and breast cancer outcomes

BackgroundIt is unclear whether germline breast cancer susceptibility gene mutations affect breast cancer related outcomes. We wanted to evaluate mutation patterns in 20 breast cancer susceptibility genes and correlate the mutations with clinical characteristics to determine the effects of these germline mutations on breast cancer prognosis.MethodsThe study cohort included 480 ethnic Chinese individuals in Taiwan with at least one of the six clinical risk factors for hereditary breast cancer: family history of breast or ovarian cancer, young age of onset for breast cancer, bilateral breast cancer, triple negative breast cancer, both breast and ovarian cancer, and male breast cancer. PCR-enriched amplicon-sequencing on a next generation sequencing platform was used to determine the germline DNA sequences of all exons and exon-flanking regions of the 20 genes. Protein-truncating variants were identified as pathogenic.ResultsWe detected a 13.5% carrier rate of pathogenic germline mutations, with BRCA2 being the most prevalent and the non-BRCA genes accounting for 38.5% of the mutation carriers. BRCA mutation carriers were more likely to be diagnosed of breast cancer with lymph node involvement (66.7% vs 42.6%; P = 0.011), and had significantly worse breast cancer specific outcomes. The 5-year disease-free survival was 73.3% for BRCA mutation carriers and 91.1% for non-carriers (hazard ratio for recurrence or death 2.42, 95% CI 1.29–4.53; P = 0.013). After adjusting for clinical prognostic factors, BRCA mutation remained an independent poor prognostic factor for cancer recurrence or death (adjusted hazard ratio 3.04, 95% CI 1.40–6.58; P = 0.005). Non-BRCA gene mutation carriers did not exhibit any significant difference in cancer characteristics or outcomes compared to those without detected mutations. Among the risk factors for hereditary breast cancer, the odds of detecting a germline mutation increased significantly with having bilateral breast cancer (adjusted odds ratio 3.27, 95% CI 1.64–6.51; P = 0.0008) or having more than one risk factor (odds ratio 2.07, 95% CI 1.22–3.51; P = 0.007).ConclusionsWithout prior knowledge of the mutation status, BRCA mutation carriers had more advanced breast cancer on initial diagnosis and worse cancer-related outcomes. Optimal approach to breast cancer treatment for BRCA mutation carriers warrants further investigation.

Risk reduction surgery (RRS) for tubo-ovarian cancer in an Irish gynaecological practice: an analysis of indications and outcomes.

High-grade serous carcinoma (HGSC) is the most common tubo-ovarian cancer. The fallopian tube harbours the precursor lesion: serous tubal intraepithelial carcinoma (STIC). Bilateral salpingo-oophorectomy is an effective risk-reducing surgical (RRS) strategy for breast cancer susceptibility gene mutation carriers (BRCAm). The value of RRS in those without defined genetic risk is unknown but these women represent a substantial cohort in prophylactic surgical practice. This is a retrospective review of RRS at an Irish university teaching hospital. One hundred and thirty women underwent RRS; group 1 = 46 BRCAm; group 2 = 19 BRCAm negative/65 genetic status unknown. Group 1 had one occult HGSC. Group 2 had no STIC or cancers and were older and more likely to have hysterectomy and benign pathology. Other pathologies included serous tubal intraepithelial lesions (STIL) (2), p53 signatures (2), endometriosis (6), fibroids/adenomyosis (4) and atypical endometrial hyperplasia (1). More than 60% of women undergoing RRS were BRCAm negative or untested. Counselling of high-risk women without defined germline mutations remains a challenge for gynaecologists because the likelihood of removing STIC lesions or occult invasive cancer is low. Removal of coincidental pathology may give added value to RRS in these women.

Loss of BRCA1 in the Cells of Origin of Ovarian Cancer Induces Glycolysis: A Window of Opportunity for Ovarian Cancer Chemoprevention.

Mutations in the breast cancer susceptibility gene 1 (BRCA1) are associated with an increased risk of developing epithelial ovarian cancer. However, beyond the role of BRCA1 in DNA repair, little is known about other mechanisms by which BRCA1 impairment promotes carcinogenesis. Given that altered metabolism is now recognized as important in the initiation and progression of cancer, we asked whether the loss of BRCA1 changes metabolism in the cells of origin of ovarian cancer. The findings show that silencing BRCA1 in ovarian surface epithelial and fallopian tube cells increased glycolysis. Furthermore, when these cells were transfected with plasmids carrying deleterious BRCA1 mutations (5382insC or the P1749R), there was an increase in hexokinase-2 (HK2), a key glycolytic enzyme. This effect was mediated by MYC and the STAT3. To target the metabolic phenotype induced by loss of BRCA1, a drug-repurposing approach was used and aspirin was identified as an agent that counteracted the increase in HK2 and the increase in glycolysis induced by BRCA1 impairment. Evidence from this study indicates that the tumor suppressor functions of BRCA1 extend beyond DNA repair to include metabolic endpoints and identifies aspirin as an ovarian cancer chemopreventive agent capable of reversing the metabolic derangements caused by loss of BRCA1. Cancer Prev Res; 10(4); 255-66. ©2017 AACR.

Biweekly gemcitabine and low-dose cisplatin in the treatment of locally advanced or metastatic pancreatic cancer patients: a single institute experience.

Gemcitabine in combination with low-dose cisplatin has shown promising activity in pancreatic cancer with manageable toxicities. The purpose of this study is to assess the activity of a combination of gemcitabine and low-dose cisplatin in the first-line treatment of metastatic and locally advanced pancreatic cancer patients. We conducted a retrospective analysis of all patients diagnosed with metastatic and locally advanced pancreatic cancer who received a combination of gemcitabine and cisplatin in the first-line setting. Patients with baseline cytopenias and elevated liver function tests were included. Patients received cisplatin at 20mg per square meter followed by gemcitabine at a dose of 1000mg per square meter at fixed dose rate every 2weeks. Patients were treated until disease progression or unacceptable toxicities. A total of 58 patients were included in the analysis. The median progression-free survival was 4.4months [95% confidence interval (CI) 3.6-6.4], and median overall survival was 6.7months (95% CI 4.4-10.9). Thirty-eight patients (66%) experienced at least one grade 3 or 4 toxicity. The most common grade 3 or 4 toxicity was hematologic toxicity (25 patients, 43%). Biweekly fixed dose rate gemcitabine combined with low-dose cisplatin shows interesting activity in advanced pancreatic cancer. This regimen is an acceptable alternative for patients ineligible for gemcitabine plus nab-paclitaxel (i.e., those with elevated bilirubin at baseline) or clinical trials. Additionally, this regimen should be considered as a first-line option for those patients with breast cancer susceptibility gene mutations (BRCA1 and/or BRCA2).

Inherited mutations in cancer susceptibility genes are common among survivors of breast cancer who develop therapy‐related leukemia

Risk factors for the development of therapy-related leukemia (TRL), an often lethal late complication of cytotoxic therapy, remain poorly understood and may differ for survivors of different malignancies. Survivors of breast cancer (BC) now account for the majority of TRL cases, making the study of TRL risk factors in this population a priority. Subjects with TRL after cytotoxic therapy for a primary BC were identified from the TRL registry at The University of Chicago. Those with an available germline DNA sample were screened with a comprehensive gene panel covering known inherited BC susceptibility genes. Clinical and TRL characteristics of all subjects and those with identified germline mutations were described. Nineteen of 88 survivors of BC with TRL (22%) had an additional primary cancer and 40 of the 70 survivors with an available family history (57%) had a close relative with breast, ovarian, or pancreatic cancer. Of the 47 subjects with available DNA, 10 (21%) were found to carry a deleterious inherited mutation in BRCA1 (3 subjects; 6%), BRCA2 (2 subjects; 4%), TP53 (tumor protein p53) (3 subjects; 6%), CHEK2 (checkpoint kinase 2) (1 subject; 2%), and PALB2 (partner and localizer of BRCA2) (1 subject; 2%). Survivors of BC with TRL have personal and family histories suggestive of inherited cancer susceptibility and frequently carry germline mutations in BC susceptibility genes. The data from the current study support the role of these genes in TRL risk and suggest that long-term follow-up studies of women with germline mutations who are treated for BC and functional studies of the effects of heterozygous mutations in these genes on bone marrow function after cytotoxic exposures are warranted. Cancer 2016;122:304-311. © 2015 American Cancer Society.