Incidence and outcome of brain and/or leptomeningeal metastases in HER2-low metastatic breast cancer in the French ESME cohort.

BACKGROUND: Breast cancer (BC) is the second most common cancer that metastasizes to the brain. Particularly up to half of patients with human epidermal growth factor receptor 2 (HER2)-positive (HER2+) metastatic breast cancer (mBC) may develop brain metastases over the course of the disease. Nevertheless, little is known about the prevalence and the outcome of brain and leptomeningeal metastases (BLMM) in HER2-low BC. We compared the cumulative incidence of BLMM and associated outcomes among patients with HER2-low, HER2-negative (HER2-) and HER2+ mBC. PATIENTS AND METHODS: This cohort study was conducted from the Epidemiological Strategy and Medical Economics (ESME) mBC database and included patients treated for mBC between 2012 and 2020 across 18 French comprehensive cancer centers and with known HER2 and hormone receptor (HR) status. The cumulative incidence of BLMM after metastatic diagnosis was estimated using a competing risk methodology with death defined as a competing event. RESULTS: 19 585 patients were included with 6118 (31.2%), 9943 (50.8%) and 3524 (18.0%) being HER2-low, HER2- and HER2+ mBC, respectively. After a median follow-up of 48.6 months [95% confidence interval (CI) 47.7-49.3 months], BLMM were reported in 4727 patients: 1192 (25.2%) were diagnosed with BLMM at first metastatic diagnosis and 3535 (74.8%) after metastatic diagnosis. Multivariable analysis adjusted for age, histological grade, metastases-free interval and HR status showed that the risk of BLMM at metastatic diagnosis was similar in patients with HER2- compared to HER2-low mBC [odds ratio (OR) (95% CI) 1.00 (0.86-1.17)] and higher in those with HER2+ compared to HER2-low [OR (95% CI) 2.23 (1.87-2.66)]. Similar results were found after metastatic diagnosis; the risk of BLMM was similar in HER2- compared to HER2-low [subdistribution hazard ratio (sHR) (95% CI) 1.07 (0.98-1.16)] and higher in the HER2+ group [sHR (95% CI) 1.56 (1.41-1.73)]. CONCLUSIONS: The prevalence and evolution of BLMM in HER2-low mBC are similar to those in patients with HER2- tumors. In contrast to patients with HER2+ mBC, the prognosis of BLMM remains dismal in this population.

Efficacy of front-line treatment for hormone receptor-positive HER2-negative metastatic breast cancer with germline BRCA1/2 mutation.

BACKGROUND: Efficacy of endocrine therapy in HR+/HER2- metastatic breast cancer could differ depending on the presence of BRCA1/2 germline mutation. METHODS: The ESME metastatic breast cancer platform (NCT03275311) is a French real world database. Multivariable models including a time-varying approach and landmark analyses assessed the association between time-dependent gBRCA status (categorised as gBRCAm, gBRCAwt (wild type), and untested), overall survival (OS), and first-line progression-free survival (PFS1). RESULTS: A total of 170 patients were gBRCAm carriers, 676 gBRCAwt, and 12,930 were untested at baseline. In the multivariable analysis, gBRCAm carriers overall had a lower OS compared to gBRCAwt (adjusted HR [95% CI] 1.26 [1.03-1.55]). gBRCAm patients treated with front-line endocrine therapy had lower adjusted OS (adjusted HR [95% CI] = 1.54 [1.03-2.32]) and PFS1 (adjusted HR [95% CI] 1.58 [1.17-2.12]) compared to gBRCAwt patients. However, for patients who received frontline chemotherapy, neither OS nor PFS1 differed between gBRCAm carriers and the other groups (HR versus gBRCAwt for OS: 1.12 [0.88-1.41], p = 0.350; PFS1: 1.09 [0.90-1.31], p = 0.379). CONCLUSION: In this large cohort of HR+/HER2- MBC patients treated in a pre-CDK4/6 inhibitors era, gBRCAm status was associated with a lower OS and lower PFS following first-line endocrine therapy, but not following first-line chemotherapy.

Alpelisib and fulvestrant in PIK3CA-mutated hormone receptor-positive HER2-negative advanced breast cancer included in the French early access program.

SOLAR-1 and BYLieve trials documented the efficacy of the PI3K-inhibitor alpelisib in pre-treated PIK3CA-mutant, hormone receptor-positive, HER2-negative (HR+/HER2-) advanced breast cancer (ABC) patients. We report here real-life data of patients prospectively registered in the French alpelisib early access program (EAP) opened to PIK3CA-mutant HR+/HER2- ABC patients treated with alpelisib and fulvestrant. Primary endpoint was PFS by local investigators using RECIST1.1. Eleven centers provided individual data on 233 consecutive patients. Patients had received a median number of 4 (range: 1-16) prior systemic treatments for ABC, including CDK4/6 inhibitor, chemotherapy, fulvestrant and everolimus in 227 (97.4%), 180 (77.3%), 175 (75.1%) and 131 (56.2%) patients, respectively. After a median follow-up of 7.1 months and 168 events, median PFS was 5.3 months (95% CI: 4.7-6.0). Among 186 evaluable patients, CBR at 6 months was 45.3% (95% CI: 37.8-52.8). In multivariable analysis, characteristics significantly associated with a shorter PFS were age < 60 years (HR = 1.5, 95% CI = 1.1-2.1), >5 lines of prior treatments (HR = 1.4, 95% CI = 1.0-2.0) and the C420R PI3KCA mutation (HR = 4.1, 95% CI = 1.3-13.6). N = 91 (39.1%) patients discontinued alpelisib due to adverse events. To our knowledge, this is the largest real-life assessment of alpelisib efficacy. Despite heavy pre-treatments, patients derived a clinically relevant benefit from alpelisib and fulvestrant.

Enrollment of older metastatic breast cancer patients in first-line clinical trials: 9-year experience of the large-scale real-life multicenter French ESME cohort.

PURPOSE: Older cancer patients are underrepresented in clinical trials. We aimed to evaluate the enrollment of older women aged 70 years old (yo) or over with metastatic breast cancer (MBC) in clinical trials. METHODS: We used the national Epidemio-Strategy and Medical Economics MBC Data Platform, a French multi-center real-life database. We selected MBC women over 70yo, without central nervous system metastases, with at least one line of systemic treatment, between January 1st, 2008 and December 31st, 2016, and had no other cancer in the 5 years before MBC. The primary objective was to evaluate the proportion of patients enrolled in clinical trials according to their age. Secondary objective was to identify variables associated with enrollment in older ones. RESULTS: 5552 women were aged ≥ 70 (median 74yo; IQR 72-77). 14,611 were less than 70. Of the older ones, 239 (4%) were enrolled in a clinical trial during first line of treatment, compared with 1529 (10.5%) for younger ones. Multivariable analysis of variables predicting for enrollment during first line of treatment in older patients were younger age (OR 0.50 [95%CI 0.33-0.76] for the 80-85yo class; OR 0.17 [95%CI 0.06-0.39] for the 85yo and more class), good ECOG Performance Status (PS 0-1) (OR 0.15 [95%CI 0.08-0.27] for the PS 2-4 class), HER2 + disease (OR 1.78 [95%CI 1.27-2.48]), type of treatment (chemotherapy/targeted therapy/immunotherapy OR 5.01 [95%CI 3.13-8.18]), and period (OR 1.65 [95%CI 1.22-2.26] for 2012-2016, compared to 2008-2011). CONCLUSION: In this large database, few older MBC patients were enrolled in a trial compared with younger ones.

De novo metastatic breast cancer in patients with a small locoregional tumour (T1-T2/N0): Characteristics and prognosis.

INTRODUCTION: The estimated rate of de novo metastatic breast cancer (dnMBC) at the time of diagnosis is between 5 to 12%. International guidelines recommend metastatic work-up (MWU) only in women with advanced breast cancer. The purpose of this study was to describe the characteristics and prognosis of patients with dnMBC diagnosed without an initial indication for MWU. METHODS: We conducted a retrospective, comparative study in dnMBC patients selected from the ESME-MBC cohort. Patients were treated in France between 2008 and 2016. We compared two populations: patients in whom dnMBC was diagnosed by staging although not indicated by guidelines (non-guideline staging [NGS]) and those in whom dnMBC was diagnosed by guideline staging (GS). RESULTS: During the study period, 22,463 patients with MBC were included in the ESME cohort. Among them, 6698 were dnMBC patients. In 247 of these patients (6% of dnMBC and 1% of the overall population), dnMBC was diagnosed by non-guideline staging. Women in this group were significantly younger (57 vs. 59 years, p = 0.02) and had fewer metastatic sites at diagnosis than dnMBC-GS patients. The two groups were not significantly different in terms of the other characteristics. Overall survival (OS) and progression-free survival (PFS) were better in the dnMBC-NGS group than in the dnMBC-GS group. The impact on survival was confirmed by univariate and multivariate analysis (HR 1.83 [1.31-2.57], p < 0.01). CONCLUSION: This study provides the first description of a very specific population. These patients with dnMBC-NGS were younger and more likely to have oligometastatic disease with a better prognosis.

Evolution of overall survival and receipt of new therapies by subtype among 20 446 metastatic breast cancer patients in the 2008-2017 ESME cohort.

BACKGROUND: Treatment strategies for metastatic breast cancer (MBC) have made great strides over the past 10 years. Real-world data allow us to evaluate the actual benefit of new treatments. ESME (Epidemio-Strategy-Medico-Economical)-MBC, a nationwide observational cohort (NCT03275311), gathers data of all consecutive MBC patients who initiated their treatment in 18 French Cancer Centres since 2008. PATIENTS AND METHODS: We evaluated overall survival (OS) in the whole cohort (N = 20 446) and among subtypes: hormone receptor positive, human epidermal growth factor 2 negative (HR+/HER2-; N = 13 590), HER2+ (N = 3919), and triple-negative breast cancer (TNBC; N = 2937). We performed multivariable analyses including year of MBC diagnosis as one of the covariates, to assess the potential OS improvement over time, and we described exposure to newly released drugs at any time during MBC history by year of diagnosis (YOD). RESULTS: The median follow-up of the whole cohort was 65.5 months (95% CI 64.6-66.7). Year of metastatic diagnosis appears as a strong independent prognostic factor for OS [Year 2016 HR 0.89 (95% CI 0.82-0.97); P = 0.009, using 2008 as reference]. This effect is driven by the HER2+ subcohort, where it is dramatic [Year 2016 HR 0.52 (95% CI 0.42-0.66); P < 0.001, using 2008 as reference]. YOD had, however, no sustained impact on OS among patients with TNBC [Year 2016 HR 0.93 (95% CI 0.77-1.11); P = 0.41, using 2008 as reference] nor among those with HR+/HER2- MBC [Year 2016 HR 1.02 (95% CI 0.91-1.13); P = 0.41, using 2008 as reference]. While exposure to newly released anti-HER2 therapies appeared very high (e.g. >70% of patients received pertuzumab from 2016 onwards), use of everolimus or eribulin was recorded in less than one-third of HR+/HER2- and TNBC cohorts, respectively, whatever YOD. CONCLUSION: OS has dramatically improved among HER2+ MBC patients, probably in association with the release of several major HER2-directed therapies, whose penetrance was high. This trend was not observed in the other subtypes, but the impact of CDK4/6 inhibitors cannot yet be assessed.

Letrozole and palbociclib versus chemotherapy as neoadjuvant therapy of high-risk luminal breast cancer.

Background: Palbociclib is a CDK4/6 inhibitor with demonstrated efficacy and safety in combination with endocrine therapy in advanced luminal breast cancer (LBC). We evaluated the respective efficacy and safety of chemotherapy and letrozole-palbociclib (LETPAL) combination as neoadjuvant treatment in patients with high-risk LBC. Patients and methods: NeoPAL (UCBG10/4, NCT02400567) is a randomised, parallel, non-comparative phase II study. Patients with ER-positive, HER2-negative, Prosigna®-defined luminal B, or luminal A and node-positive, stage II-III breast cancer, not candidate for breast-conserving surgery, were randomly assigned to either letrozole (2.5 mg daily) and palbociclib (125 mg daily, 3 weeks/4) during 19 weeks, or to FEC100 (5FU 500 mg/m2, epirubicin 100 mg/m2, cyclophosphamide 500 mg/m2)×3 21-day courses followed by docetaxel 100 mg/m2×3 21-day courses. Primary end point was residual cancer burden (RCB 0-I rate). Secondary end points included clinical response, proliferation-based markers, and safety. Results: Overall, 106 patients were randomised [median Prosigna® ROR Score 71 (22-93)]. RCB 0-I was observed in four and eight patients in LETPAL [7.7% (95% CI 0.4-14.9)] and chemotherapy [15.7% (95% CI 5.7-25.7)] arms, respectively. Pathological complete response rates were 3.8% and 5.9%. Clinical response (75%) and breast-conserving surgery rates (69%) were similar in both arms. Preoperative Endocrine Prognostic Index 0 scores (breast cancer-specific survival) were observed in 17.6% and 8.0% of patients in LETPAL and chemotherapy arms, respectively. Safety profile was as expected, with 2 versus 17 serious adverse events (including 11 grade 4 serious AEs in the chemotherapy arm). Conclusion: LETPAL combination was associated with poor pathological response but encouraging clinical and biomarker responses in Prosigna®-defined high-risk LBC. Contemporary chemotherapy regimen was associated with poor pathological and biomarker responses, with a much less favourable safety profile. LETPAL combination might represent an alternative to chemotherapy in early high-risk LBC. Clinical Trial Number: NCT02400567.

Endocrine therapy or chemotherapy as first-line therapy in hormone receptor-positive HER2-negative metastatic breast cancer patients.

BACKGROUND: For hormone receptor-positive (HR+) human epidermal growth factor receptor 2 (HER2-) negative metastatic breast cancer (MBC), international guidelines recommend endocrine therapy as first-line treatment, except in case of 'visceral crisis'. In the latter case, chemotherapy is preferred. Few studies have compared these two strategies. We used the Epidemiological Strategy and Medical Economics (ESME) programme, UNICANCER, a large national observational database (NCT03275311), to address this question. METHODS: All patients who initiated treatment for a newly diagnosed HR+ HER2-negative MBC between January 2008 and December 2014 in any of the 18 French Comprehensive Cancer Centers participating to ESME were selected. Patients should be aromatase inhibitor (AI)-sensitive (no previous AI or relapse occurring more than 1 year after last adjuvant AI). Objectives of the study were evaluation of progression-free and overall survival (OS) according to the type of first-line treatment adjusted on main prognostic factors using a propensity score. RESULTS: Six thousand two hundred sixty-five patients were selected: 2733 (43.6%) received endocrine therapy alone, while 3532 (56.4%) received chemotherapy as first-line therapy. Among the latter, 2073 (58.7%) received maintenance endocrine therapy. Median OS was 60.78 months (95% confidence interval [CI], 57.16-64.09) and 49.64 months (95% CI, 47.31-51.64; p < 0.0001) for patients receiving endocrine therapy alone and chemotherapy ± maintenance endocrine therapy, respectively. However, this difference was not significant after adjusting on the propensity score (hazard ratio: 0.943, 95% CI 0.863-1.030, p = 0.19). CONCLUSION: In this large retrospective cohort of patients with AI-sensitive metastatic luminal BC, OS was similar, whether first-line treatment was chemotherapy or endocrine therapy. In agreement with international guidelines, endocrine therapy should be the first choice for first-line systemic treatment for MBC in the absence of visceral crisis.

HER2-positivity rates in breast cancer: no variation over time when clinicopathological features and testing are stable.

HER2 status is essential for breast cancer subtyping and for systemic treatment decisions as patients with HER2-positive tumours can benefit from anti-HER2 targeted therapies. However, few data are available on the current HER2-positive breast cancers rate and its evolution across years. Using data from the Côte d'Or breast cancer registry, we identified, between 1998 and 2011, 3220 women with invasive breast cancer diagnosed in the same laboratory which carries out regular internal quality controls and participates in multiannual international quality control programmes. Throughout the studied period of time, despite an increase of annual breast cancer cases, HER2 positivity rate remained stable (13.1%; P = 0.495), as did the proportion of tumours with positive hormone receptor status (P = 0.467) and the proportion of SBR grade II/III tumours (P = 0.747). Other characteristics, less strongly associated with HER2-positive status, showed either no annual variation (nodal and metastatic status, tumour size) or an annual positive trend (mean age, lobular carcinomas) or an annual negative trend (ductal carcinomas). These data reveal that in a population with stable clinical and pathological characteristics, and with the use of standardised assays, HER2 positivity rate remains stable over time. These results also emphasise that current HER2 positivity rate is lower than initially reported.

Predictive factors of pathologic complete response of HER2-positive breast cancer after preoperative chemotherapy with trastuzumab: development of a specific predictor and study of its utilities using decision curve analysis.

PURPOSE: The aim of this study was to assess the Institut Gustave Roussy/M.D. Anderson Cancer Center (IGR/MDACC) nomogram in predicting pathologic complete response (pCR) to preoperative chemotherapy in a cohort of human epidermal growth factor receptor 2 (HER2)-positive tumors treated with preoperative chemotherapy with trastuzumab. We then combine clinical and pathological variables associated with pCR into a new nomogram specific to HER2-positive tumors treated by preoperative chemotherapy with trastuzumab. PATIENTS AND METHODS: Data from 270 patients with HER2-positive tumors treated with preoperative chemotherapy with trastuzumab at the Institut Curie and at the Georges François Leclerc Cancer Center were used to assess the IGR/MDACC nomogram and to subsequently develop a new nomogram for pCR based on multivariate logistic regression. Model performance was quantified in terms of calibration and discrimination. We studied the utility of the new nomogram using decision curve analysis. RESULTS: The IGR/MDACC nomogram was not accurate for the prediction of pCR in HER2-positive tumors treated by preoperative chemotherapy with trastuzumab, with poor discrimination (AUC = 0.54, 95% CI 0.51-0.58) and poor calibration (p = 0.01). After uni- and multivariate analysis, a new pCR nomogram was built based on T stage (TNM), hormone receptor status, and Ki67 (%). The model had good discrimination with an area under the curve (AUC) at 0.74 (95% CI 0.70-0.79) and adequate calibration (p = 0.93). By decision curve analysis, the model was shown to be relevant between thresholds of 0.3 and 0.7. CONCLUSION: To the best of our knowledge, ours is the first nomogram to predict pCR in HER2-positive tumors treated by preoperative chemotherapy with trastuzumab. To ensure generalizability, this model needs to be externally validated.

[Non-metastatic triple-negative breast cancer in 2016: Definitions and management]. / Tumeurs localisées du sein triple négatives en 2016 : définitions et prise en charge.

Triple-negative breast cancer (TN), as defined by the triple negativity in immunohistochemistry: the absence of estrogen receptor, progesterone receptor and the absence of overexpression or amplification of HER2, corresponds to 15 % of invasive breast cancers. This is a very heterogeneous group of tumors both at the genomic and transcriptomic level and at morphological, clinical and prognostic level. Although there are some good prognosis forms, the majority of TN tumors is characterized by a poor prognosis with a greater frequency of visceral metastases and a maximum risk of relapse in the first two years after diagnosis. Systemic adjuvant treatment with chemotherapy is almost always indicated. The surgical treatment and radiotherapy treatment should be comparable to the other subtypes and obey the same rules of oncologic surgery. TN tumors are not associated with a higher risk of locoregional relapse after conservative treatment and adjuvant radiotherapy. Optimization of systemic therapies is currently and for the last decade a challenge. A number of targeted therapies and efficiency biomarkers identification of these targeted therapies is essential to allow significant progress in optimizing systemic therapy for these tumors.

A phase II trial of abiraterone acetate plus prednisone in patients with triple-negative androgen receptor positive locally advanced or metastatic breast cancer (UCBG 12-1).

BACKGROUND: Several expression array studies identified molecular apocrine breast cancer (BC) as a subtype that expresses androgen receptor (AR) but not estrogen receptor α. We carried out a multicentre single-arm phase II trial in women with AR-positive, estrogen, progesterone receptor and HER2-negative (triple-negative) metastatic or inoperable locally advanced BC to assess the efficacy and safety of abiraterone acetate (AA) plus prednisone. PATIENTS AND METHODS: Patients with a metastatic or locally advanced, centrally reviewed, triple-negative and AR-positive (≥10% by immunohistochemistry, IHC) BC were eligible. Any number of previous lines of chemotherapy was allowed. AA (1000 mg) was administered once a day with prednisone (5 mg) twice a day until disease progression or intolerance. The primary end point was clinical benefit rate (CBR) at 6 months defined as the proportion of patients presenting a complete response (CR), partial response (PR) or stable disease (SD) ≥6 months. Secondary end points were objective response rate (ORR), progression-free survival (PFS) and safety. RESULTS: One hundred and forty-six patients from 27 centres consented for IHC central review. Of the 138 patients with sufficient tissue available, 53 (37.6%) were AR-positive and triple-negative, and 34 of them were included from July 2013 to December 2014. Thirty patients were eligible and evaluable for the primary end point. The 6-month CBR was 20.0% [95% confidence interval (CI) 7.7%-38.6%], including 1 CR and 5 SD ≥6 months, 5 of them still being under treatment at the time of analysis (6.4+, 9.2+, 14.5+, 17.6+, 23.4+ months). The ORR was 6.7% (95% CI 0.8%-22.1%). The median PFS was 2.8 months (95% CI 1.7%-5.4%). Fatigue, hypertension, hypokalaemia and nausea were the most common drug-related adverse events; the majority of them being grade 1 or 2. CONCLUSIONS: AA plus prednisone treatment is beneficial for some patients with molecular apocrine tumours and five patients are still on treatment. CLINICALTRIALSGOV: NCT01842321.

Stage IV breast cancer: a population-based study about prognostic factors according to HER2 and HR status.

We aim to describe trends in net survival (NS) and to assess the prognostic factors among women with de novo metastatic breast cancer (MBC) according to human epidermal growth factor receptor 2 (HER2) and hormone receptor (HR) status. Data on women suffering from de novo MBC and diagnosed from 1998 to 2009 were provided by the Côte-d'Or breast cancer registry. NS was described using the Pohar Perme estimator and prognostic factors were investigated in a generalised linear model. We identified 232 patients (mean age = 64.7). Median NS was 29.2 months, 1- and 5-year NS were 76% and 26% respectively. The survival trend in patients with HER2-positive tumours who did not receive trastuzumab was similar to that in women with triple-negative tumours. A higher relative excess risk of death by cancer was observed for high-grade tumours [RER, relative excess rates = 1.76 (95% CI, confidence intervals: 1.17-2.62) for Scarff Bloom Richardson grade 3 vs. 1 + 2], while a lower risk was observed for luminal tumours [RER = 0.49 (95% CI: 0.27-0.89)] and HER2-positive tumours treated with trastuzumab [RER = 0.28 (95% CI: 0.14-0.59)], both compared with triple-negative tumours. Surgery of the primary tumour was associated with better survival [RER = 0.43 (95% CI: 0.28-0.68)]. With half of the women dead before 29 months, stage IV breast cancer still has a bleak outlook. Progress should continue with new target therapies for both HR and HER2 receptors.