Patients' preference of trastuzumab administration (subcutaneous versus intravenous) in HER2-positive metastatic breast cancer: Results of the randomised MetaspHer study

HannaH (NCT00950300) and PrefHer (NCT01401166) studies validated the subcutaneous (H-s.c.) formulation of trastuzumab as effective and safe as intravenous (H-i.v.) and highly preferred by patients in early breast cancer. The present randomised MetaspHer trial (NCT01810393) is the first study assessing patient's preference in metastatic setting.

METHODS

Patients with HER2-positive metastatic breast cancer who completed a first line chemotherapy with trastuzumab and achieved a long-term response lasting more than 3 years were randomised to receive 3 cycles of 600-mg fixed-dose adjuvant H-s.c., followed by 3 cycles of standard H-i.v., or the reverse sequence. Primary end-point was overall preference for H-s.c. or H-i.v. at cycle six, assessed by Patient Preference Questionnaire (PPQ). Secondary end-points included healthcare professional (HCP) satisfaction; safety and tolerability; quality of life.

RESULTS

Hundred and thirteen patients were randomised and treated. H-s.c. was preferred by 79/92 evaluable intent-to-treat patients (85.9%, 95% confidence interval [CI; 78.8-93.0]; p < 0.001), 13/92 preferred H-i.v. (14.1%, 95% CI [7.0-21.3]). HCPs were most satisfied with H-s.c. (56/88 available data, 63.6%, [53.6-73.7]). On the safety population, adverse events occurred in 73 (67.6%) and 49 (44.1%) patients during the H-s.c. and H-i.v. periods, respectively; 7 (6.5%) and 4 (3.6%) were grade ≥ III, 3 (2.8%) and 2 (1.8%) were serious.

CONCLUSION

The safety was consistent with the known H-i.v. and H-s.c. profiles without safety concern raised. Definitively, patients preferred H-s.c. as reported in early stage by PrefHer study.

Cancers de l’ovaire BRCA muté : consultation d’oncogénétique et prescription des inhibiteurs de PARP

BRCA MUTATED OVARIAN CARCINOMAS

GENETIC COUNSELING AND PARP INHIBITORS PRESCRIPTION: Upon the availability of the PARP inhibitors in relapsed ovarian carcinoma, the pathways of the oncogenetic counseling were modified. Any research for a constitutional alteration of the BRCA1 and BRCA2 genes must be accompanied by an oncogenetic counseling. BRCA testing is recommended from the diagnosis to every woman with an ovarian or fallopian tube or peritoneum of high grade adenocarcinoma, whatever the age at the diagnosis and her family history. In case of sensitive relapse or potential inclusion in a clinical trial and in the absence of preliminary constitutional research, the oncogenetic counseling is organized according to a fast track pathway and a somatic analysis can be realized in parallel. Today, olaparib is indicated for patients with a high grade serous ovarian or fallopian tube or peritoneum adenocarcinoma, with deleterious mutation of BRCA genes (constitutional or somatic), and in sensitive platinum relapse, and in maintenance therapy after a response to chemotherapy including platinum. The indication of a treatment with olaparib can be discussed in multidisciplinary staff for the other non-serous high grade ovarian carcinoma if all other criteria are gathered. Olaparib is prescribed in monotherapy, to start at the latest 8 weeks after the last chemotherapy cycle, under narrow surveillance, because of its gastrointestinal and hematologic toxicities.

Adverse events (AEs) with maintenance olaparib tablets in patients (pts) with BRCA-mutated (BRCAm) platinum-sensitive relapsed serous ovarian cancer (PSR SOC): Phase III SOLO2 trial

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Background: In the SOLO2 trial (ENGOT Ov-21; NCT01874353), maintenance therapy with the PARP inhibitor olaparib significantly improved PFS vs placebo (PBO) in BRCAm PSR SOC pts (HR 0.30, 95% CI 0.22–0.41, P<0.0001; median 19.1 vs 5.5 months) and was well tolerated (Pujade-Lauraine et al, SGO 2017). We analyzed AEs in SOLO2, the first study in PSR SOC to use the olaparib tablet formulation. Methods: Pts with BRCAm PSR SOC, who were in response to platinum chemotherapy, were treated with olaparib (300 mg bid; tablets; n=195) or PBO (n=99) until progression. AEs were graded by CTCAE v4.0. Results: The most common AEs with olaparib – nausea, fatigue/asthenia, anemia, and vomiting – were largely grade 1–2, though anemia was the most common grade ≥3 AE. AEs of fatigue/asthenia, vomiting and nausea generally improved as treatment continued, though fatigue/asthenia and anemia could last for several months (table). Most AEs were manageable by supportive treatment, dose interruptions (olaparib, 45%; PBO, 18%) and dose reductions (olaparib, 25%; PBO, 3%). Discontinuation of olaparib due to AEs was minimal (11%); anemia and neutropenia were the only AEs leading to discontinuation of olaparib in >one pt. Conclusions: Most AEs experienced by pts receiving olaparib tablets in SOLO2 were low grade and manageable. Initial nausea, vomiting and fatigue generally improved with ongoing treatment. The majority of AEs first occurred within the first three months of treatment. AEs causing treatment discontinuation were rare and mainly hematological. Clinical trial information: NCT01874353. [Table: see text]

Two prognostic populations of ovarian cancer patients defined by CA125 modeled kinetic parameter KELIM (AGO-OVAR 7 & 9; ICON 7 AGO/GINECO/ MRC CTU/GCIG trials)

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Background: Longitudinal CA125 kinetics during treatment can be assessed by mathematical models. The modeled CA125 elimination parameter KELIM (with 3-4 timepoints) was an early prognostic factor in CALYPSO (Gynecol Oncol 2013). Validating the prognostic value of KELIM in phase 3 trial datasets with different 1st line treatments was warranted. Methods: Data from AGO-OVAR 9 (training set: carboplatin-paclitaxel (CP) +/- gemcitabine; n=1742); AGO-OVAR 7 (validation set: CP +/- topotecan; n=1308); and ICON 7 trials (validation set: CP +/- bevacizumab; n=1528) were analyzed. CA125 profiles were fit to nonlinear mixed effect equations, and KELIM estimated in all patients at 100 days. KELIM prognostic value was tested regarding PFS and OS against other prognostic factors (stage; pathology; grade; arms; GCIG CA125 criteria; Oza groups in ICON 7) using univariate/multivariate tests. Results: KELIM (≤ or > median 0.0598) had reproducible independent prognostic value for PFS (AGO 9: HR = 0.60 [0.53-0.69]; AGO 7: HR = 0.58 [0.40-0.83]; ICON-7: HR=0.65 [0.44-0.96]) and for OS (AGO 9: HR = 0.55 [0.47-0.64]; AGO 7: HR = 0.55 [0.35-0.86]; ICON-7: HR=0.49 [0.41-0.57]) by multivariate tests. Other significant factors for PFS & OS: stage IV in AGO7 & 9 (HR=6.0 to 8.3) and ICON 7 poor progn group (PFS HR=2.24 PFS; OS HR=2.22 [1.9-2.6]). KELIM prognostic value was independent on regimen arms (Table), maintained within ICON7 progn groups (best OS gain with bevac if poor progn & unfav KELIM), and better than GCIG CA125 (inconsistent progn value). Conclusions: The reproducible & independent early prognostic value of KELIM regarding PFS and OS is validated. Easily calculable online, it early discriminates 2 ovarian cancer populations for PFS & OS whatever treatments, and is a new reference prognostic factor. [Table: see text]

[Breast cancer screening: On our way to the future]

Breast cancer remains a potentially lethal disease, which requires aggressive treatments and is associated with long-term consequences. Its prognosis is linked to both tumor biology and burden at diagnosis. Although treatments have allowed important improvements in prognosis over the past 20 years, breast cancer screening remains necessary. Mammographic screening allows earlier stage diagnoses and a decrease of breast cancer specific mortality. However, breast cancer screening modalities should be revised with the objective to address demonstrated limitations of mammographic screening (limited benefit, imperfect sensitivity and specificity, overdiagnoses, radiation-induced morbidity). Furthermore, both objective and perceived performances of screening procedures should be improved. Numerous large international efforts are ongoing, leading to scientific progresses that should have rapid clinical implications in this area. Among them is improvement of imaging techniques performance, development of real time diagnosis, and development of new non radiological screening techniques such as the search for circulating tumor DNA, development of biomarkers able to allow precise risk evaluation and stratified screening. As well, overtreatment is currently addressed by biomarker-based de-escalation clinical trials. These advances need to be associated with strong societal support, as well as major paradigm changes regarding the way health and cancer prevention is perceived by individuals.

Abstract P2-02-17: T-DM1 in HER2-negative metastatic breast cancer patients with HER2-amplified circulating tumor cells: Current status of the CirCe T-DM1 phase II trial

Background: Liquid biopsy can reassess key therapeutic targets in metastatic breast cancer. Several studies showed that a low albeit significant rate of metastatic breast cancer initially considered as HER2-negative can be reclassified as HER2-positive by systematic biopsy procedures. We report here the current status of the CirCe T-DM1 trial [NCT01975142] which aims to demonstrate the clinical utility of HER2 status reassessment on circulating tumor cells (CTCs).

Methods: The first step of the trial consists in CTC count and HER2/CEP17 FISH on detected CTCs (CellSearch, Janssen Diagnostics) in patients (pts) with measurable disease progressing after the second line of chemotherapy. Pts with amplified CTCs (HER2/CEP17 ratio equal or higher than 2.2) are eligible to the treatment step of the study in two distinct cohorts: low CTC count (1 or 2 HER2-amplified CTCs) and high CTC count (3 and more HER2-amplified CTCs). In the treatment step has a Simon's two stage design, the anti-HER2 antibody-drug conjugate T-DM1 being administered until tumor progression. The primary objective of the trial is the confirmed response rate (RECIST). This trial is supported by Roche.

Results: CirCe T-DM1 has been initiated in 10 centers in France. As of June 2015, 105 metastatic breast cancers pts considered as HER2-negative were screened. 29 pts (27%) had no CTC detected, 68 pts (65%) had at least 1 CTC detected with no HER2 amplification, and 8 pts (8%) exhibited HER2-amplified CTCs. Among the 8 pts, 1 pt had 5 HER2-amplified CTC, 2 pts had 2 HER2-amplified CTC and 5 pts had 1 HER2-amplified CTC. HER2/CEP17 ratios among HER2-amplified CTCs ranged from 2.5 to 7. Five of the 8 pts were treated by T-DM1. One objective confirmed partial tumor response has been observed (20%).

Conclusion: The accrual is ongoing; the first efficacy assessment will occur after having treated 14 pts. This innovative trial highlights the promise and the complexity of liquid biopsy-based programs in the era of precision medicine: scarcity of the target, reliability and reproducibility of the target assessment, major efficacy when the target is matched to the appropriate drug.

Citation Format: Bidard F-C, Romieu G, Jacot W, Cottu P, Dieras V, Lerebours F, Servent V, Luporsi E, Lortholary A, Tubiana-Mathieu N, Espie M, Bollet M, Bourgeois H, Renaud N, Pelissier S, Armanet S, Baeten K, Pierga J-Y. T-DM1 in HER2-negative metastatic breast cancer patients with HER2-amplified circulating tumor cells: Current status of the CirCe T-DM1 phase II trial. [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 P2-02-17.

Mutation screening of MIR146A/B and BRCA1/2 3'-UTRs in the GENESIS study

Although a wide number of breast cancer susceptibility alleles associated with various levels of risk have been identified to date, about 50% of the heritability is still missing. Although the major BRCA1 and BRCA2 genes are being extensively screened for truncating and missense variants in breast and/or ovarian cancer families, potential regulatory variants affecting their expression remain largely unexplored. In an attempt to identify such variants, we focused our attention on gene regulation mediated by microRNAs (miRs). We screened two genes, MIR146A and MIR146B, producing miR-146a and miR-146b-5p, respectively, that regulate BRCA1, and the 3'- untranslated regions (3'-UTRs) of BRCA1 and BRCA2 in the GENESIS French national case/control study (BRCA1- and BRCA2-negative breast cancer cases with at least one sister with breast cancer and matched controls). We identified one rare variant in MIR146A, four in MIR146B, five in BRCA1 3'-UTR and one in BRCA2 3'-UTR in 716 index cases and 619 controls. Among these 11 rare variants, 7 were identified each in 1 index case. None of the three relevant MIR146A/MIR146B variants affected the pre-miR sequences. The potential causality of the four relevant BRCA1/BRCA2 3'-UTRs variants was evaluated with luciferase reporter assays and co-segregation studies, as well as with bioinformatics analyses to predict miRs-binding sites, RNA secondary structures and RNA accessibility. This is the first study to report the screening of miR genes and of BRCA2 3'-UTR in a large series of familial breast cancer cases. None of the variant identified in this study gave convincing evidence of potential pathogenicity.

GENESIS: a French national resource to study the missing heritability of breast cancer

Background

Less than 20 % of familial breast cancer patients who undergo genetic testing for BRCA1 and BRCA2 carry a pathogenic mutation in one of these two genes. The GENESIS (GENE SISter) study was designed to identify new breast cancer susceptibility genes in women attending cancer genetics clinics and with no BRCA1/2 mutation.

Methods

The study involved the French national network of family cancer clinics. It was based on enrichment in genetic factors of the recruited population through case selection relying on familial criteria, but also on the consideration of environmental factors and endophenotypes like mammary density or tumor characteristics to assess potential genetic heterogeneity. One of the initial aims of GENESIS was to recruit affected sibpairs. Siblings were eligible when index cases and at least one affected sister were diagnosed with infiltrating mammary or ductal adenocarcinoma, with no BRCA1/2 mutation. In addition, unrelated controls and unaffected sisters were recruited. The enrolment of patients, their relatives and their controls, the collection of the clinical, epidemiological, familial and biological data were centralized by a coordinating center.

Results

Inclusion of participants started in February 2007 and ended in December 2013. A total of 1721 index cases, 826 affected sisters, 599 unaffected sisters and 1419 controls were included. 98 % of participants completed the epidemiological questionnaire, 97 % provided a blood sample, and 76 % were able to provide mammograms. Index cases were on average 59 years old at inclusion, were born in 1950, and were 49.7 years of age at breast cancer diagnosis. The mean age at diagnosis of affected sisters was slightly higher (51.4 years). The representativeness of the control group was verified.

Conclusions

The size of the study, the availability of biological specimens and the clinical data collection together with the detailed and complete epidemiological questionnaire make this a unique national resource for investigation of the missing heritability of breast cancer, by taking into account environmental and life style factors and stratifying data on endophenotypes to decrease genetic heterogeneity.

Volasertib Versus Chemotherapy in Platinum-Resistant or -Refractory Ovarian Cancer: A Randomized Phase II Groupe des Investigateurs Nationaux pour l'Etude des Cancers de l'Ovaire Study

PURPOSE

Volasertib is a potent and selective cell-cycle kinase inhibitor that induces mitotic arrest and apoptosis by targeting Polo-like kinase. This phase II trial evaluated volasertib or single-agent chemotherapy in patients with platinum-resistant or -refractory ovarian cancer who experienced failure after treatment with two or three therapy lines.

PATIENTS AND METHODS

Patients were randomly assigned to receive either volasertib 300 mg by intravenous infusion every 3 weeks or an investigator's choice of single-agent, nonplatinum, cytotoxic chemotherapy. The primary end point was 24-week disease control rate. Secondary end points included best overall response, progression-free survival (PFS), safety, quality of life, and exploratory biomarker analyses.

RESULTS

Of the 109 patients receiving treatment, 54 received volasertib and 55 received chemotherapy; demographics were well balanced. The 24-week disease control rates for volasertib and chemotherapy were 30.6% (95% CI, 18.0% to 43.2%) and 43.1% (95% CI, 29.6% to 56.7%), respectively, with partial responses in seven (13.0%) and eight (14.5%) patients, respectively. Median PFS was 13.1 weeks and 20.6 weeks for volasertib and chemotherapy (hazard ratio, 1.01; 95% CI, 0.66 to 1.53). Six patients (11%) receiving volasertib achieved PFS fore more than 1 year, whereas no patient receiving chemotherapy achieved PFS greater than 1 year. No relationship between the expression of the biomarkers tested and their response was determined. Patients treated with volasertib experienced more grade 3 and 4 drug-related hematologic adverse events (AEs) and fewer nonhematologic AEs than did patients receiving chemotherapy. Discontinuation resulting from AEs occurred in seven (13.0%) and 15 (27.3%) patients in the volasertib and chemotherapy arms, respectively. Both arms showed similar effects on quality of life.

CONCLUSION

Single-agent volasertib showed antitumor activity in patients with ovarian cancer. AEs in patients receiving volasertib were mainly hematologic and manageable.

Standard first-line chemotherapy with or without nintedanib for advanced ovarian cancer (AGO-OVAR 12): a randomised, double-blind, placebo-controlled phase 3 trial

BACKGROUND

Angiogenesis is a target in the treatment of ovarian cancer. Nintedanib, an oral triple angiokinase inhibitor of VEGF receptor, platelet-derived growth factor receptor, and fibroblast growth factor receptor, has shown activity in phase 2 trials in this setting. We investigated the combination of nintedanib with standard carboplatin and paclitaxel chemotherapy in patients with newly diagnosed advanced ovarian cancer.

METHODS

In this double-blind phase 3 trial, chemotherapy-naive patients (aged 18 years or older) with International Federation of Gynecology and Obstetrics (FIGO) IIB-IV ovarian cancer and upfront debulking surgery were stratified by postoperative resection status, FIGO stage, and planned carboplatin dose. Patients were randomly assigned (2:1) via an interactive voice or web-based response system to receive six cycles of carboplatin (AUC 5 mg/mL per min or 6 mg/mL per min) and paclitaxel (175 mg/m(2)) in addition to either 200 mg of nintedanib (nintedanib group) or placebo (placebo group) twice daily on days 2-21 of every 3-week cycle for up to 120 weeks. Patients, investigators, and independent radiological reviewers were masked to treatment allocation. The primary endpoint was investigator-assessed progression-free survival analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01015118.

FINDINGS

Between Dec 9, 2009, and July 27, 2011, 1503 patients were screened and 1366 randomly assigned by nine study groups in 22 countries: 911 to the nintedanib group and 455 to the placebo group. 486 (53%) of 911 patients in the nintedanib group experienced disease progression or death compared with 266 (58%) of 455 in the placebo group. Median progression-free survival was significantly longer in the nintedanib group than in the placebo group (17·2 months [95% CI 16·6-19·9] vs 16·6 months [13·9-19·1]; hazard ratio 0·84 [95% CI 0·72-0·98]; p=0·024). The most common adverse events were gastrointestinal (diarrhoea: nintedanib group 191 [21%] of 902 grade 3 and three [<1%] grade 4 vs placebo group nine [2%] of 450 grade 3 only) and haematological (neutropenia: nintedanib group 180 [20%] grade 3 and 200 (22%) grade 4 vs placebo group 90 [20%] grade 3 and 72 [16%] grade 4; thrombocytopenia: 105 [12%] and 55 [6%] vs 21 [5%] and eight [2%]; anaemia: 108 [12%] and 13 [1%] vs 26 [6%] and five [1%]). Serious adverse events were reported in 376 (42%) of 902 patients in the nintedanib group and 155 (34%) of 450 in the placebo group. 29 (3%) of 902 patients in the nintedanib group experienced serious adverse events associated with death compared with 16 (4%) of 450 in the placebo group, including 12 (1%) in the nintedanib group and six (1%) in the placebo group with a malignant neoplasm progression classified as an adverse event by the investigator. Drug-related adverse events leading to death occurred in three patients in the nintedanib group (one without diagnosis of cause; one due to non-drug-related sepsis associated with drug-related diarrhoea and renal failure; and one due to peritonitis) and in one patient in the placebo group (cause unknown).

INTERPRETATION

Nintedanib in combination with carboplatin and paclitaxel is an active first-line treatment that significantly increases progression-free survival for women with advanced ovarian cancer, but is associated with more gastrointestinal adverse events. Future studies should focus on improving patient selection and optimisation of tolerability.

FUNDING

Boehringer Ingelheim.

Targeted Sequencing of the Mitochondrial Genome of Women at High Risk of Breast Cancer without Detectable Mutations in BRCA1/2

Breast Cancer is a complex multifactorial disease for which high-penetrance mutations have been identified. Approaches used to date have identified genomic features explaining about 50% of breast cancer heritability. A number of low- to medium penetrance alleles (per-allele odds ratio < 1.5 and 4.0, respectively) have been identified, suggesting that the remaining heritability is likely to be explained by the cumulative effect of such alleles and/or by rare high-penetrance alleles. Relatively few studies have specifically explored the mitochondrial genome for variants potentially implicated in breast cancer risk. For these reasons, we propose an exploration of the variability of the mitochondrial genome in individuals diagnosed with breast cancer, having a positive breast cancer family history but testing negative for BRCA1/2 pathogenic mutations. We sequenced the mitochondrial genome of 436 index breast cancer cases from the GENESIS study. As expected, no pathogenic genomic pattern common to the 436 women included in our study was observed. The mitochondrial genes MT-ATP6 and MT-CYB were observed to carry the highest number of variants in the study. The proteins encoded by these genes are involved in the structure of the mitochondrial respiration chain, and variants in these genes may impact reactive oxygen species production contributing to carcinogenesis. More functional and epidemiological studies are needed to further investigate to what extent variants identified may influence familial breast cancer risk.

Cardiac toxicity events in the PHARE trial, an adjuvant trastuzumab randomised phase III study

BACKGROUND

This article reports, the cardiac toxicity according to 6- versus 12-month durations of adjuvant trastuzumab in PHARE randomised trial (NCT00381901).

PATIENTS AND METHODS

Cardiac follow-up and Left Ventricular Ejection Fraction (LVEF) assessment by echocardiography or multigated acquisition scan were performed every 3 months while patients received trastuzumab and after completion of treatment over the first 2 years and every 6 months afterwards. The primary cardiac end-point was Cardiac Heart Failure (CHF) defined as New York Heart Association (NYHA) class III or IV. The secondary cardiac end-points were: cardiac events, cardiac dysfunctions defined by NYHA class I and II; LVEF decreases, cardiac recoveries. The cardiac subcommittee reviewed cardiac events and assessed if patients had favourable outcomes or not on the basis of trends from LVEF measurements.

RESULTS

Among 3380 patients the cardiac dysfunction assessment included 14,055 and 13,218 LVEF measurements in the 12- and 6-month arms. The overall incidences of CHF were 0.65% (11/1690) and 0.53% (9/1690) in the 12 and 6 month arms, respectively (p>0.05). Cardiac dysfunction occurred in 5.9% (100/1690) and 3.4% (58/1690) of patients in the 12 and 6 month arms, respectively (p=0.001). Recoveries were observed for the majority patients and 0.79% (27/3380) of patients experienced an unfavourable cardiac outcome.

CONCLUSION

PHARE confirm that the incidence of cardiac end-points remains low and mostly reversible after trastuzumab. Identification at baseline of cardiac risk categories of patients should be of interest to provide an optimal adaptation of adjuvant modalities and a shorter duration might be an option.

Breast Cancer Risk Associated with Estrogen Exposure and Truncating Mutation Location in BRCA1/2 Carriers

BACKGROUND

Mutations in BRCA1/2 confer a high risk of breast cancer, but literature values of this risk vary. A genotype-phenotype correlation has been found in both genes, and the effect of reproductive factors differs according to mutation location. Therefore, we hypothesize that such a variation may exist for other factors related to estrogen exposure.

METHODS

We used a weighted Cox regression model to assess variation in breast cancer risk with these factors using location of mutation in homogeneous breast cancer risk region of BRCA1/2 in the GENEPSO study.

RESULTS

We found that late age at menarche reduced breast cancer risk by 31% and that among BRCA1 carriers, a long or a short menstrual cycle increased risk (by 65% and 73%, respectively). Among premenopausal women, overweight was associated with a 45% decrease in risk whereas underweight was associated with an increased risk (HR, 2.40). A natural menopause, mainly after age 50, was associated with a high breast cancer risk (HR, 2.46), and a significant interaction between menopause status and the location of mutations was found leading up to 10% variation in absolute risk according to the age at menopause.

CONCLUSIONS

As observed in the general population, a late menarche, a long or a short menstrual cycle, over- or underweight, and being postmenopausal were associated with breast cancer risk in BRCA1/2 carriers. The association with the menopause was observed only when the mutation was located in the "high-risk" zones.

IMPACT

Taking into account modifier factors, location of mutation might be important for the clinical management of BRCA1/2 mutation carriers.