Decision Coaching for Healthy Women With BRCA1/2 Pathogenic Variants­Findings of the Randomized Controlled EDCP-BRCA Trial.

BACKGROUND: Women with BRCA1/2 pathogenic variants (PVs) have a choice of preventive options. To help these women decide for themselves, we developed and implemented a decision coaching (DC) program and evaluated it for congruence between the participants' desired and actual roles in decision-making. METHODS: Healthy BRCA1/2 PV carriers (from 25 to 60 years of age) were recruited at six centers in Germany. Those returning baseline T1-questionnaires were randomly assigned to the intervention group (IG) or the control group (CG). The IG attended a nurse-led DC program. The primary outcome was congruence between the participants' desired and actual roles in decision-making. The secondary outcomes included an active role, satisfaction, decisional conflict, and knowledge. Follow-up data were obtained by questionnaire at 12 weeks (T2) and 6 months (T3). RESULTS: Of the 413 women who were recruited, 389 returned baseline T1 questionnaires. At T2, the IG and CG groups did not differ significantly in congruence between their desired and actual roles in decision-making (0.12 [95% confidence interval -0.03; 0.28], p=0.128), with a slightly higher congruence in the CG. Women in both groups were more active at T2 than their stated preference at T1, with a notably higher percentage in the IG (IG: 40%, CG: 24.4%; [-25.1; -6.1]). IG participants were more satisfied with the role that they had assumed and had less decisional conflict and greater knowledge. CONCLUSION: These findings imply that this DC program can help women with BRCA1/2 PVs participate actively in decision-making with regard to preventive measures.

Prevalence of Pathogenic Germline Variants in Women with Non-Familial Unilateral Triple-Negative Breast Cancer.

Introduction: International guidelines recommend genetic testing for women with familial breast cancer at an expected prevalence of pathogenic germline variants (PVs) of at least 10%. In a study sample of the German Consortium for Hereditary Breast and Ovarian Cancer (GC-HBOC), we have previously shown that women with TNBC diagnosed before the age of 50 years but without a family history of breast or ovarian cancer (sTNBC) meet this criterion. The present study investigates the PV prevalence in BRCA1, BRCA2, and nine additional cancer predisposition genes in an extended sTNBC study sample including a cohort of women with a later age at sTNBC diagnosis. Patients and Methods: In 1,600 women with sTNBC (median age at diagnosis: 41 years, range 19-78 years), we investigated the association between age at diagnosis and PV occurrence in cancer predisposition genes using logistic regression. Results: 260 sTNBC patients (16.2%) were found to have a PV in cancer predisposition genes (BRCA1: n = 170 [10.6%]; BRCA2: n = 46 [2.9%], other: n = 44 [2.8%]). The PV prevalence in women diagnosed between 50 and 59 years (n = 194) was 11.3% (22/194). Logistic regression showed a significant increase in PV prevalence with decreasing age at diagnosis (OR 1.41 per 10 years younger age at diagnosis; 95% confidence interval: 1.21-1.65; p < 0.001). The PV prevalence predicted by the model was above 10% for diagnoses before the age of 56.8 years. Conclusion: Based on the data presented, we recommend genetic testing by gene panel analysis for sTNBC patients diagnosed before the age of 60 years. Due to the still uncertain estimate for women with sTNBC diagnosed above the age of 60 years, further studies are needed.

The effect of denosumab on disseminated tumor cells (DTCs) of breast cancer patients with neoadjuvant treatment: a GeparX translational substudy.

BACKGROUND: Disseminated tumor cells (DTCs) in the bone marrow are observed in about 40% at primary diagnosis of breast cancer and predict poor survival. While anti-resorptive therapy with bisphosphonates was shown to eradicate minimal residue disease in the bone marrow, the effect of denosumab on DTCs, particularly in the neoadjuvant setting, is largely unknown. The recent GeparX clinical trial reported that denosumab, applied as an add-on treatment to nab-paclitaxel based neoadjuvant chemotherapy (NACT), did not improve the patient's pathologic complete response (pCR) rate. Herein, we analyzed the predictive value of DTCs for the response to NACT and interrogated whether neoadjuvant denosumab treatment may eradicate DTCs in the bone marrow. METHODS: A total of 167 patients from the GeparX trial were analyzed for DTCs at baseline by immunocytochemistry using the pan-cytokeratin antibody A45-B/B3. Initially DTC-positive patients were re-analyzed for DTCs after NACT ± denosumab. RESULTS: At baseline, DTCs were observed in 43/167 patients (25.7%) in the total cohort, however their presence did not predict response to nab-paclitaxel based NACT (pCR rates: 37.1% in DTC-negative vs. 32.6% DTC-positive; p = 0.713). Regarding breast cancer subtypes, the presence of DTCs at baseline was numerically associated with response to NACT in TNBC patients (pCR rates: 40.0% in DTC-positive vs. 66.7% in DTC-negative patients; p = 0.16). Overall, denosumab treatment did not significantly increase the given DTC-eradication rate of NACT (NACT: 69.6% DTC-eradication vs. NACT + denosumab: 77.8% DTC-eradication; p = 0.726). In TNBC patients with pCR, a numerical but statistically non-significant increase of DTC-eradication after NACT + denosumab was observed (NACT: 75% DTC-eradication vs. NACT + denosumab: 100% DTC-eradication; p = 1.00). CONCLUSION: This is the first study worldwide, demonstrating that neoadjuvant add-on denosumab over a short-term period of 24 months does not increase the DTC-eradication rate in breast cancer patients treated with NACT.

Recommendation and Acceptance of Counselling for Familial Cancer Risk in Newly Diagnosed Breast Cancer Cases.

Background: In clinical routine, not every patient who is offered genetic counselling and diagnostics in order to investigate a familial cancer risk predisposition opts for it. Little is known about acceptance of counselling and testing in newly diagnosed breast cancer cases in Germany. Methods: All primary breast cancer cases and patients with DCIS (ductal carcinoma in situ) treated at the University Hospital of Dresden between 2016 and 2019 were included. The number of tumor board recommendations for genetic counselling on the basis of the GC-HBOC risk criteria was recorded. Acceptance was analyzed by number of cases with counselling in the GC-HBOC-Center Dresden. Results: Of 996 primary breast cancer and DCIS cases, 262 (26.3%) were eligible for genetic counselling. Recommendation for genetic counselling was accepted by 64.1% (168/262). Of these 90.5% (152/168) opted for molecular genetic analysis. The acceptance rate for counselling increased between 2016 and 2019 from 58.3 to 72.6%. Altogether, 20.4% (31/152) patients were found to carry a pathogenic variant in the breast cancer genes BRCA1 or BRCA2. Conclusion: Acceptance of recommendation is increasing as clinical consequences augment. Optimization in providing information about hereditary cancer risk and in accessibility of counselling and testing is required to further improve acceptance of recommendation.

Patient-Reported Satisfaction after Prophylactic Operations of the Breast.

BACKGROUND: Prophylactic mastectomies in carriers of mutations in BRCA1 or BRCA2 are becoming increasingly more accepted. We investigated the outcome after prophylactic mastectomy, especially regarding satisfaction with the procedure, in a monocenter study. METHODS: BRCA1/2 mutation carriers and non-carriers with elevated pedigree-based cancer risk were followed prospectively in a structured surveillance program between 2000 and 2017. A retrospective telephone survey was conducted among all patients with documented prophylactic mastectomy. Complications and satisfaction with the decision for prophylactic mastectomy were recorded. RESULTS: 39 patients who opted for a prophylactic mastectomy (38 BRCA1/2 mutation carriers and 1 non-carrier) were interviewed. Mostly nipple-sparing mastectomy with reconstruction was performed (87%). Half of the patients (22/39; 56.4%) had a history of unilateral breast cancer. The median time since prophylactic mastectomy was 5.6 years. While 61.5% did not report any complications, flap loss was seen in 15% (3/20) and moderate limitations in everyday life were present in 20% (7/35). An improvement in quality of life was noticed by 82% after prophylactic mastectomy and no patient expressed regret with regard to the decision. CONCLUSIONS: Prophylactic mastectomy is a procedure with risk for long-term complications in some cases. Our results confirm high satisfaction with the decision and improved quality of life.

BRCA1/2 missense mutations and the value of in-silico analyses.

INTRODUCTION: The clinical implications of genetic variants in BRCA1/2 in healthy and affected individuals are considerable. Variant interpretation, however, is especially challenging for missense variants. The majority of them are classified as variants of unknown clinical significance (VUS). Computational (in-silico) predictive programs are easy to access, but represent only one tool out of a wide range of complemental approaches to classify VUS. With this single-center study, we aimed to evaluate the impact of in-silico analyses in a spectrum of different BRCA1/2 missense variants. METHODS: We conducted mutation analysis of BRCA1/2 in 523 index patients with suspected hereditary breast and ovarian cancer (HBOC). Classification of the genetic variants was performed according to the German Consortium (GC)-HBOC database. Additionally, all missense variants were classified by the following three in-silico prediction tools: SIFT, Mutation Taster (MT2) and PolyPhen2 (PPH2). RESULTS: Overall 201 different variants, 68 of which constituted missense variants were ranked as pathogenic, neutral, or unknown. The classification of missense variants by in-silico tools resulted in a higher amount of pathogenic mutations (25% vs. 13.2%) compared to the GC-HBOC-classification. Altogether, more than fifty percent (38/68, 55.9%) of missense variants were ranked differently. Sensitivity of in-silico-tools for mutation prediction was 88.9% (PPH2), 100% (SIFT) and 100% (MT2). CONCLUSION: We found a relevant discrepancy in variant classification by using in-silico prediction tools, resulting in potential overestimation and/or underestimation of cancer risk. More reliable, notably gene-specific, prediction tools and functional tests are needed to improve clinical counseling.

Spectrum of genetic variants of BRCA1 and BRCA2 in a German single center study.

BACKGROUND: Determination of mutation status of BRCA1 and BRCA2 has become part of the clinical routine. However, the spectrum of genetic variants differs between populations. The aim of this study was to deliver a comprehensive description of all detected variants. METHODS: In families fulfilling one of the German Consortium for Hereditary Breast and Ovarian Cancer (GC-HBOC) criteria for genetic testing, one affected was chosen for analysis. DNA of blood lymphocytes was amplified by PCR and prescreened by DHPLC. Aberrant fragments were sequenced. All coding exons and splice sites of BRCA1 and BRCA2 were analyzed. Screening for large rearrangements in both genes was performed by MLPA. RESULTS: Of 523 index patients, 121 (23.1%) were found to carry a pathogenic or likely pathogenic (class 4/5) mutation. A variant of unknown significance (VUS) was detected in 73/523 patients (13.9%). Two mutations p.Gln1756Profs*74 and p.Cys61Gly comprised 42.3% (n = 33/78) of all detected pathogenic mutations in BRCA1. Most of the other mutations were unique mutations. The most frequently detected mutation in BRCA2 was p.Val1283Lys (13.9%; n = 6/43). Altogether, 101 different neutral genetic variants were counted in BRCA1 (n = 35) and in BRCA2 (n = 66). CONCLUSION: The two most frequently detected mutations are founder mutations in Poland and Czech Republic. More similarities seem to be shared with our direct neighbor countries compared to other European countries. For comparison of the extended genotype, a shared database is needed.