Duration of Adjuvant Aromatase-Inhibitor Therapy in Postmenopausal Breast Cancer.

BACKGROUND: For postmenopausal women with hormone-receptor-positive breast cancer, the most effective duration for adjuvant therapy with an aromatase inhibitor remains unclear. METHODS: In this prospective, phase 3 trial, we randomly assigned postmenopausal women with hormone-receptor-positive breast cancer who had received 5 years of adjuvant endocrine therapy to receive the aromatase inhibitor anastrozole for an additional 2 years (2-year group, receiving a total of 7 years) or an additional 5 years (5-year group, receiving a total of 10 years). The primary end point was disease-free survival. The primary analysis included all the patients who were still participating in the trial and who had no recurrence 2 years after randomization (i.e., when treatment in the 2-year group had ended). Secondary end points were overall survival, contralateral breast cancer, second primary cancer, and clinical bone fracture. RESULTS: Among the 3484 women who were enrolled in the trial, 3208 remained in the trial without disease progression after the first 2 years of extended anastrozole treatment following randomization. Among these women, disease progression or death occurred in 335 women in each treatment group in the primary-analysis set at 8 years (hazard ratio, 0.99; 95% confidence interval [CI], 0.85 to 1.15; P = 0.90). No between-group differences occurred in most secondary end points, and subgroup analyses did not indicate differences in any particular subgroup. The risk of clinical bone fracture was higher in the 5-year group than in the 2-year group (hazard ratio, 1.35; 95% CI, 1.00 to 1.84). CONCLUSIONS: In postmenopausal women with hormone-receptor-positive breast cancer who had received 5 years of adjuvant endocrine therapy, extending hormone therapy by 5 years provided no benefit over a 2-year extension but was associated with a greater risk of bone fracture. (Funded by AstraZeneca and the Austrian Breast and Colorectal Cancer Study Group; ABCSG-16/SALSA ClinicalTrials.gov number, NCT00295620.).

Adjuvant Olaparib for Patients with BRCA1- or BRCA2-Mutated Breast Cancer.

BACKGROUND: Poly(adenosine diphosphate-ribose) polymerase inhibitors target cancers with defects in homologous recombination repair by synthetic lethality. New therapies are needed to reduce recurrence in patients with BRCA1 or BRCA2 germline mutation-associated early breast cancer. METHODS: We conducted a phase 3, double-blind, randomized trial involving patients with human epidermal growth factor receptor 2 (HER2)-negative early breast cancer with BRCA1 or BRCA2 germline pathogenic or likely pathogenic variants and high-risk clinicopathological factors who had received local treatment and neoadjuvant or adjuvant chemotherapy. Patients were randomly assigned (in a 1:1 ratio) to 1 year of oral olaparib or placebo. The primary end point was invasive disease-free survival. RESULTS: A total of 1836 patients underwent randomization. At a prespecified event-driven interim analysis with a median follow-up of 2.5 years, the 3-year invasive disease-free survival was 85.9% in the olaparib group and 77.1% in the placebo group (difference, 8.8 percentage points; 95% confidence interval [CI], 4.5 to 13.0; hazard ratio for invasive disease or death, 0.58; 99.5% CI, 0.41 to 0.82; P<0.001). The 3-year distant disease-free survival was 87.5% in the olaparib group and 80.4% in the placebo group (difference, 7.1 percentage points; 95% CI, 3.0 to 11.1; hazard ratio for distant disease or death, 0.57; 99.5% CI, 0.39 to 0.83; P<0.001). Olaparib was associated with fewer deaths than placebo (59 and 86, respectively) (hazard ratio, 0.68; 99% CI, 0.44 to 1.05; P = 0.02); however, the between-group difference was not significant at an interim-analysis boundary of a P value of less than 0.01. Safety data were consistent with known side effects of olaparib, with no excess serious adverse events or adverse events of special interest. CONCLUSIONS: Among patients with high-risk, HER2-negative early breast cancer and germline BRCA1 or BRCA2 pathogenic or likely pathogenic variants, adjuvant olaparib after completion of local treatment and neoadjuvant or adjuvant chemotherapy was associated with significantly longer survival free of invasive or distant disease than was placebo. Olaparib had limited effects on global patient-reported quality of life. (Funded by the National Cancer Institute and AstraZeneca; OlympiA ClinicalTrials.gov number, NCT02032823.).

Efficacy and safety of tailored and dose-dense adjuvant chemotherapy and trastuzumab for resected HER2-positive breast cancer: Results from the phase 3 PANTHER trial.

BACKGROUND: Dose-dense (DD) adjuvant chemotherapy improves outcomes in early breast cancer (BC). However, there are no phase 3 randomized data to inform on its combination with trastuzumab for patients with human epidermal growth factor receptor 2 (HER2)-positive disease. METHODS: This was a protocol-predefined secondary analysis of the randomized phase 3 Pan-European Tailored Chemotherapy (PANTHER) trial. Women 65 years old or younger with node-positive or high-risk, node-negative BC were randomized 1:1 to either tailored (according to hematologic nadirs) and DD epirubicin and cyclophosphamide followed by docetaxel or standard 5-fluorouracil, epirubicin, and cyclophosphamide plus docetaxel every 3 weeks. Patients with HER2-positive disease received 1 year of adjuvant trastuzumab. The primary endpoint was BC relapse-free survival. In addition, HER2-positive patients and an equal number of HER2-negative patients matched for age, treatment group, and institution who were enrolled at Swedish sites were asked to participate in a predefined study of cardiac safety and underwent echocardiography or multigated acquisition scanning and electrocardiography at the baseline and at 4 and 6 years of follow-up. RESULTS: There were 342 HER2-positive patients; 335 received at least 1 dose of trastuzumab, and 29 patients discontinued trastuzumab prematurely. Relapse-free survival was not statistically significantly in favor of the tailored and DD group (hazard ratio, 0.68; 95% confidence interval, 0.37-1.27; P = .231). Cardiac outcomes after 4 and 6 years of follow-up did not differ significantly between HER2-positive and HER2-negative patients or between the 2 treatment groups. CONCLUSIONS: The combination of DD chemotherapy and trastuzumab decreased the relative risk for relapse by 32% in comparison with standard treatment, a statistically nonsignificant difference. Its efficacy and safety merit further evaluation as part of both escalation and de-escalation strategies.

Adjuvant bevacizumab-containing therapy in triple-negative breast cancer (BEATRICE): primary results of a randomised, phase 3 trial.

BACKGROUND: The addition of bevacizumab to chemotherapy improves progression-free survival in metastatic breast cancer and pathological complete response rates in the neoadjuvant setting. Micrometastases are dependent on angiogenesis, suggesting that patients might benefit from anti-angiogenic strategies in the adjuvant setting. We therefore assessed the addition of bevacizumab to chemotherapy in the adjuvant setting for women with triple-negative breast cancer. METHODS: For this open-label, randomised phase 3 trial we recruited patients with centrally confirmed triple-negative operable primary invasive breast cancer from 360 sites in 37 countries. We randomly allocated patients aged 18 years or older (1:1 with block randomisation; stratified by nodal status, chemotherapy [with an anthracycline, taxane, or both], hormone receptor status [negative vs low], and type of surgery) to receive a minimum of four cycles of chemotherapy either alone or with bevacizumab (equivalent of 5 mg/kg every week for 1 year). The primary endpoint was invasive disease-free survival (IDFS). Efficacy analyses were based on the intention-to-treat population, safety analyses were done on all patients who received at least one dose of study drug, and plasma biomarker analyses were done on all treated patients consenting to biomarker analyses and providing a measurable baseline plasma sample. This trial is registered with ClinicalTrials.gov, number NCT00528567. FINDINGS: Between Dec 3, 2007, and March 8, 2010, we randomly assigned 1290 patients to receive chemotherapy alone and 1301 to receive bevacizumab plus chemotherapy. Most patients received anthracycline-containing therapy; 1638 (63%) of the 2591 patients had node-negative disease. At the time of analysis of IDFS, median follow-up was 31·5 months (IQR 25·6-36·8) in the chemotherapy-alone group and 32·0 months (27·5-36·9) in the bevacizumab group. At the time of the primary analysis, IDFS events had been reported in 205 patients (16%) in the chemotherapy-alone group and in 188 patients (14%) in the bevacizumab group (hazard ratio [HR] in stratified log-rank analysis 0·87, 95% CI 0·72-1·07; p=0·18). 3-year IDFS was 82·7% (95% CI 80·5-85·0) with chemotherapy alone and 83·7% (81·4-86·0) with bevacizumab and chemotherapy. After 200 deaths, no difference in overall survival was noted between the groups (HR 0·84, 95% CI 0·64-1·12; p=0·23). Exploratory biomarker assessment suggests that patients with high pre-treatment plasma VEGFR-2 might benefit from the addition of bevacizumab (Cox interaction test p=0·029). Use of bevacizumab versus chemotherapy alone was associated with increased incidences of grade 3 or worse hypertension (154 patients [12%] vs eight patients [1%]), severe cardiac events occurring at any point during the 18-month safety reporting period (19 [1%] vs two [<0·5%]), and treatment discontinuation (bevacizumab, chemotherapy, or both; 256 [20%] vs 30 [2%]); we recorded no increase in fatal adverse events with bevacizumab (four [<0·5%] vs three [<0·5%]). INTERPRETATION: Bevacizumab cannot be recommended as adjuvant treatment in unselected patients with triple-negative breast cancer. Further follow-up is needed to assess the potential effect of bevacizumab on overall survival.

Trastuzumab mediates antibody-dependent cell-mediated cytotoxicity and phagocytosis to the same extent in both adjuvant and metastatic HER2/neu breast cancer patients.

BACKGROUND: Monoclonal antibodies (mAb), such as trastuzumab are a valuable addition to breast cancer therapy. Data obtained from neoadjuvant settings revealed that antibody-dependent cell-mediated cytotoxicity (ADCC) is a major mechanism of action for the mAb trastuzumab. Conflicting results still call into question whether disease progression, prolonged treatment or concomitant chemotherapy influences ADCC and related immunological phenomena. METHODS: We analyzed the activity of ADCC and antibody-dependent cell-mediated phagocytosis (ADCP) of peripheral blood mononuclear cells (PBMCs) from human epidermal growth factor receptor 2 (HER2/neu) positive breast cancer patients receiving trastuzumab therapy either in an adjuvant (n = 13) or metastatic (n = 15) setting as well as from trastuzumab treatment-naive (t-naive) HER2/neu negative patients (n = 15). PBMCs from healthy volunteers (n = 24) were used as controls. ADCC and ADCP activity was correlated with the expression of antibody binding Fc-gamma receptor (FcγR)I (CD64), FcγRII (CD32) and FcγRIII (CD16) on CD14+ (monocytes) and CD56+ (NK) cells, as well as the expression of CD107a+ (LAMP-1) on CD56+ cells and the total amount of CD4+CD25+FOXP3+ (Treg) cells. In metastatic patients, markers were correlated with progression-free survival (PFS). RESULTS: ADCC activity was significantly down regulated in metastatic, adjuvant and t-naive patient cohorts as compared to healthy controls. Reduced ADCC activity was inversely correlated with the expression of CD107a on CD56+ cells in adjuvant patients. ADCC and ADCP activity of the patient cohorts were similar, regardless of treatment duration or additional chemotherapy. PFS in metastatic patients inversely correlated with the number of peripheral Treg cells. CONCLUSION: The reduction of ADCC in patients as compared to healthy controls calls for adjuvant strategies, such as immune-enhancing agents, to improve the activity of trastuzumab. However, efficacy of trastuzumab-specific ADCC and ADCP appears not to be affected by treatment duration, disease progression or concomitant chemotherapy. This finding supports the application of trastuzumab at any stage of the disease.

Plasma HMGB-1 after the initial dose of epirubicin/docetaxel in cancer.

BACKGROUND: The response of breast cancer patients to neoadjuvant chemotherapy (NCT) is highly heterogeneous, and reliable predictive instruments remain to be defined. High-mobility group box-1 (HMGB-1) protein is a cell death marker, which is easily detectable in plasma. We hypothesized that the initial dose of NCT with epirubicin/docetaxel induces changes in plasma HMGB-1 which could allow for an early prediction of response to therapy. MATERIALS AND METHODS: First, we analysed whether epirubicin/docetaxel releases HMGB-1 from HCC1143 breast cancer cells in vitro. Thereafter, plasma HMGB-1 levels before and 1-4 days after the first dose of epirubicin/docetaxel-based NCT were determined in 41 breast cancer patients and correlated with pathological response to treatment. RESULTS: Treatment of HCC1143 cells with epirubicin/docetaxel resulted in a significant HMGB-1 release in vitro. In vivo, HMGB-1 levels increased significantly only in responders (pathological complete response or partial remission, n = 22) but not in nonresponders (stable or progressive disease, n = 19). CONCLUSION: Our data suggest that early dynamic changes of plasma HMGB1 could be a promising biomarker to predict the final response to NCT in breast cancer patients.

Impact of HER-2-targeted therapy on overall survival in patients with HER-2 positive metastatic breast cancer.

Upon disease progression on trastuzumab-based therapy, patients with HER-2 positive metastatic breast cancer (MBC) may switch to lapatinib or continue on trastuzumab. We aimed to assess the impact of both strategies on overall survival (OS) in all patients treated for HER-2 positive MBC at the Medical University Vienna from 1999 until 2009. A total of 201 patients were identified from a breast cancer data base. Of these 115 (57.2%) received multiple lines of trastuzumab-based therapy, whereas 58 (28.9%) were treated with a single line. A control group of 28 patients (13.9%) had never received trastuzumab as they were treated before 1999, when trastuzumab was registered. OS from diagnosis of metastatic disease was defined as primary study endpoint. Trastuzumab significantly prolonged OS in HER-2 positive MBC (41 versus 13 months; p < 0.001). Administration of multiple lines further improved OS; this, however, did not reach statistical significance (47 versus 28 months; p = 0.069). Positive estrogen receptor (ER) status (HR 1.6; 95% CI 1.13-2.27) was associated with better outcome compared to negative estrogen receptor status (p = 0.02). Addition of lapatinib did not improve OS significantly in patients with prior trastuzumab-based therapy (62 versus 47 months; p = n.s.). Patients receiving lapatinib after diagnosis of BM, however, experienced an improvement of OS (22 versus 5 months; p = 0.022). Trastuzumab improves OS in patients with HER-2 positive MBC with further nonsignificant improvement when administered in multiple lines. Lapatinib did not further improve OS in the entire population; however, lapatinib might improve OS in patients with BM.

Does the number of 6-monthly adjuvant zoledronate infusions received affect treatment efficacy for early breast cancer? A sub-study of ABCSG-12.

BACKGROUND: The widespread adoption of adjuvant bisphosphonate therapy for postmenopausal early breast cancer (EBC) patients was based on results of the Early Breast Cancer Trialist Group (EBCTCG) meta-analysis. Despite multiple regimens evaluated, there was no signal of varying efficacy with type, dose/dose intensity of bisphosphonate administration. We evaluated the effect of early treatment cessation using long-term outcome data from the ABCSG-12 trial. PATIENTS AND METHODS: ABCSG-12 randomized 1803 hormone-receptor positive EBC patients on ovarian suppression between 1999 and 2006 to receive 4 mg zoledronic acid 6-monthly or not (and tamoxifen or anastrozole, 2:2 factorial design). In the current study, we evaluated whether the number of zoledronate infusions had an impact on breast cancer-specific outcomes. We hypothesized that amongst patients who received at least one zoledronate infusion, the number of infusions had no effect on outcomes. Time-to-event endpoints were analysed with Cox models and Kaplan Meier curves starting from a 3-year landmark. BMD analysis was restricted to patients who participated in the BMD sub-study. RESULTS: 725 patients who received at least one zoledronate infusion were included in the time-to-event analysis. There was no statistically significant difference in disease-free or overall survival in the patients who received ≤6 zoledronate infusions (n = 170) compared to those who received ≥7 zoledronate infusions (n = 555). CONCLUSIONS: Comparable to efforts to de-escalate treatment duration in metastatic bone disease, there was no evidence to indicate that a reduced number of zoledronate infusions is associated with reduced adjuvant efficacy. Further studies to define optimal regimens of adjuvant bone-targeted therapies are required.

Influence of the American ODAC statement on Austrian bevacizumab prescribing practice for metastatic breast cancer.

BACKGROUND: Results of trial E2100 led to the accelerated approval of bevacizumab as first-line therapy for patients with metastatic breast cancer (MBC) in the U.S. in February 2008. Based on results from subsequent trials, the U.S. Food and Drug Administration Oncologic Drugs Advisory Committee (ODAC) issued a statement proposing to withdraw the license for bevacizumab in July 2010, whereas bevacizumab approval for MBC was not withdrawn in Europe. In this nationwide survey, we investigated the influence of the discrepancy between the ODAC and European Medicines Agency (EMA) positions on the prescription practice of bevacizumab for MBC in Austria during the period January 2006 to June 2011. METHODS: The absolute number of bevacizumab administrations for MBC patients per month in all Austrian hospitals within the mentioned time frame was retrieved from a comprehensive national database. Bevacizumab prescription numbers for other malignancies were retrieved in order to rule out that a change in bevacizumab prescribing practice might reflect general changes in Austrian health care policy. RESULTS: A steady increase in bevacizumab use was seen from January 2006 to June 2010 (42 versus 1,357 administrations per month) for MBC. Thereafter, a significant decline in bevacizumab prescriptions for MBC became evident, with numbers dropping to 842 in March 2011 and 662 in June 2011. Bevacizumab prescriptions showed only minor variations in control cohorts. CONCLUSIONS: The Austrian bevacizumab prescribing practice in MBC patients was significantly influenced by the ODAC statement issued in July 2010, whereas the EMA position was accepted to a lesser degree.

Neoadjuvant chemotherapy increases the rate of breast conservation in lobular-type breast cancer patients.

INTRODUCTION: Our study aims to determine whether patients with lobular-type breast cancer have significantly improved rates of breast conservation (BCT) after neoadjuvant chemotherapy (nCT). METHODS: Patients who received nCT and surgery within three prospective trials between 1995 and 2007 at the Medical University of Vienna were retrospectively analyzed. RESULTS: 325 patients had median follow-up of 53 months; 21% had lobular cancer, and 70% of these women were initially scheduled for mastectomy (MX). Twenty-one finally received BCT, yielding a MX-BCT turnover rate of 45%. Of patients primarily scheduled for BCT, 20% had to finally undergo MX in lobular cancer. The 256 patients with ductal-type breast cancer finally had a MX-BCT turnover rate of 52% (p = 0.561 versus lobular) and a BCT-MX turnover rate of 15% (p = 0.933 versus lobular). Secondary MX after initial BCT was necessary in 2% (ductal) and 10% (lobular, p = 0.110). There was no difference in local recurrence in lobular- as compared with ductal-type breast cancer patients after BCT (2.7% versus 10%, p = 0.135), nor was a difference seen in lobular breast cancer patients when comparing BCT with MX (2.7% versus 3.4%, p = 0.795). Tumor type was not an independent predictor for either BCT or local recurrence. CONCLUSION: We do not suggest excluding patients with lobular-type breast cancer who are primarily scheduled for MX from nCT, since BCT rates may still increase by 45% without influencing the oncologic outcome.

Adjuvant endocrine therapy plus zoledronic acid in premenopausal women with early-stage breast cancer: 62-month follow-up from the ABCSG-12 randomised trial.

BACKGROUND: Analysis of the Austrian Breast and Colorectal Cancer Study Group trial-12 (ABCSG-12) at 48 months' follow-up showed that addition of zoledronic acid to adjuvant endocrine therapy significantly improved disease-free survival. We have now assessed long-term clinical efficacy including disease-free survival and disease outcomes in patients receiving anastrozole or tamoxifen with or without zoledronic acid. METHODS: ABSCG-12 is a randomised, controlled, open-label, two-by-two factorial, multicentre trial in 1803 premenopausal women with endocrine-receptor-positive early-stage (stage I-II) breast cancer receiving goserelin (3.6 mg every 28 days), comparing the efficacy and safety of anastrozole (1 mg per day) or tamoxifen (20 mg per day) with or without zoledronic acid (4 mg every 6 months) for 3 years. Randomisation (1:1:1:1 ratio) was computerised and based on the Pocock and Simon minimisation method to balance the four treatment arms across eight prognostic variables (age, neoadjuvant chemotherapy, pathological tumour stage; lymph-node involvement, type of surgery or locoregional therapy, complete axillary dissection, intraoperative radiation therapy, and geographical region). Treatment allocation was not masked. The primary endpoint was disease-free survival (defined as disease recurrence or death) and analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00295646; follow-up is ongoing. FINDINGS: At a median follow-up of 62 months (range 0-114.4 months), more than 2 years after treatment completion, 186 disease-free survival events had been reported (53 events in 450 patients on tamoxifen alone, 57 in 453 patients on anastrozole alone, 36 in 450 patients on tamoxifen plus zoledronic acid, and 40 in 450 patients on anastrozole plus zoledronic acid). Zoledronic acid reduced risk of disease-free survival events overall (HR 0.68, 95% CI 0.51-0.91; p=0.009), although the difference was not significant in the tamoxifen (HR 0.67, 95% CI 0.44-1.03; p=0.067) and anastrozole arms (HR 0.68, 95% CI 0.45-1.02; p=0.061) assessed separately. Zoledronic acid did not significantly affect risk of death (30 deaths with zoledronic acid vs 43 deaths without; HR 0.67, 95% CI 0.41-1.07; p=0.09). There was no difference in disease-free survival between patients on tamoxifen alone versus anastrozole alone (HR 1.08, 95% CI 0.81-1.44; p=0.591), but overall survival was worse with anastrozole than with tamoxifen (46 vs 27 deaths; HR 1.75, 95% CI 1.08-2.83; p=0.02). Treatments were generally well tolerated, with no reports of renal failure or osteonecrosis of the jaw. Bone pain was reported in 601 patients (33%; 349 patients on zoledronic acid vs 252 not on the drug), fatigue in 361 (20%; 192 vs 169), headache in 280 (16%; 147 vs 133), and arthralgia in 266 (15%; 145 vs 121). INTERPRETATION: Addition of zoledronic acid improved disease-free survival in the patients taking anastrozole or tamoxifen. There was no difference in disease-free survival between patients receiving anastrozole and tamoxifen overall, but those on anastrozole alone had inferior overall survival. These data show persistent benefits with zoledronic acid and support its addition to adjuvant endocrine therapy in premenopausal patients with early-stage breast cancer. FUNDING: AstraZeneca; Novartis.

Effects of capecitabine as part of neo-/adjuvant chemotherapy - A meta-analysis of individual breast cancer patient data from 13 randomised trials including 15,993 patients.

BACKGROUND: Despite the large number of patients with early breast cancer (EBC) who have been treated with capecitabine in randomised trials, no individual patient data meta-analysis has been conducted. The primary objective was to examine the effect of capecitabine on disease-free survival (DFS), and the secondary objectives were to analyse distant DFS (DDFS), overall survival (OS), pathological complete response (for neoadjuvant studies) and the interaction between capecitabine-related toxicity and treatment effect. METHODS: www. CLINICALTRIALS: gov and www.pubmed.ncbi.nlm.nih.gov were searched using the following criteria: use of capecitabine for EBC as adjuvant or neoadjuvant therapy; multicentre randomised trial with >100 patients; recruitment completed, and outcomes available. Required data were available for 13 trials. RESULTS: Individual data from 15,993 patients were collected. Cox regression analyses of all included patients revealed that the addition of capecitabine did not alter DFS significantly compared with treatment without capecitabine (hazard ratio [HR] 0.952; 95% CI 0.895-1.012; P value = 0.115). There was also no effect on DFS in the subset of studies where capecitabine was given instead of another drug (HR 1.035; 95% CI 0.945-1.134; P = 0.455). However, capecitabine administered in addition to the standard systemic treatment improved DFS (HR 0.888; 95% CI 0.817-0.965; P = 0.005). An OS improvement was observed in the entire cohort (HR 0.892; 95% CI 0.824-0.965, P = 0.005) and in the subset of capecitabine addition (HR 0.837; 95% CI 0.751, 0.933, P = 0.001). Subgroup analyses revealed that triple-negative breast cancer (TNBC) patients benefitted from treatment with capecitabine overall and in addition to other systemic treatments in terms of DFS and OS. CONCLUSION: Capecitabine was able to improve DFS and OS in patients with TNBC and in all patients with EBC when administered in addition to systemic treatment.

Long-Term Outcomes of Adjuvant Denosumab in Breast Cancer.

BACKGROUND: Adjuvant aromatase inhibitors increase osteoporosis and fractures in patients with hormone receptor­positive breast cancer. We have previously reported outcomes of the ABCSG-18 (study 18 from the Austrian Breast & Colorectal Cancer Study Group) trial showing that adjuvant anti­receptor activator of nuclear factor-κB ligand denosumab treatment counteracts these adverse effects and may improve outcomes. We report here the final long-term outcomes. METHODS: ABCSG-18 is a prospective, double-blind, placebo-controlled, phase 3 trial in which 3425 postmenopausal patients with early hormone receptor­positive breast cancer receiving aromatase inhibitor therapy were randomly assigned in 58 trial centers to receive either denosumab 60 mg or placebo administered subcutaneously every 6 months. The primary end point was the time to first clinical fracture after randomization. Secondary disease outcome­related end points were disease-free survival (DFS), bone metastasis­free survival (BMFS), and overall survival (OS). RESULTS: For this final protocol-defined analysis, median follow-up is 8 years (interquartile range, 6 to 9.6 years). There were 309 versus 368 DFS events (hazard ratio, 0.83; 95% confidence interval [CI], 0.71 to 0.97) in the denosumab versus the placebo group, respectively, resulting in an absolute 9-year DFS benefit of 3.5 percentage points (79.4 vs. 75.9%). Adjuvant denosumab improved BMFS by 2.5 percentage points (88.9 vs. 86.4%; hazard ratio, 0.81; 95% CI, 0.65 to 1.00) and OS by 1.0 percentage point (90.9 vs. 89.9%; hazard ratio, 0.80; 95% CI, 0.64 to 1.01). No new toxicities for this dose of adjuvant denosumab were observed. CONCLUSIONS: DFS, BMFS, and OS continued to show benefit in this final long-term analysis of ABCSG-18. There were no new toxicities. (Funded by Amgen; ClinicalTrials.gov number, NCT00556374.)

A Randomized Phase II Study of Anti-CSF1 Monoclonal Antibody Lacnotuzumab (MCS110) Combined with Gemcitabine and Carboplatin in Advanced Triple-Negative Breast Cancer.

PURPOSE: This phase II study determined the efficacy of lacnotuzumab added to gemcitabine plus carboplatin (gem-carbo) in patients with advanced triple-negative breast cancer (TNBC). PATIENTS AND METHODS: Female patients with advanced TNBC, with high levels of tumor-associated macrophages not amenable to curative treatment by surgery or radiotherapy were enrolled. Lacnotuzumab was dosed at 10 mg/kg every 3 weeks, ± a dose on cycle 1, day 8. Gemcitabine (1,000 mg/m2) and carboplatin (dose in mg calculated by area under the curve [mg/mL/min] × (glomerular filtration rate [mL/min] + 25 [mL/min]) were dosed every 3 weeks. Treatment continued until unacceptable toxicity, disease progression, or discontinuation by physician/patient. RESULTS: Patients received lacnotuzumab + gem-carbo (n = 34) or gem-carbo (n = 15). Enrollment was halted due to recruitment challenges owing to rapid evolution of the therapeutic landscape; formal hypothesis testing of the primary endpoint was therefore not performed. Median progression-free survival was 5.6 months [90% confidence interval (CI), 4.47-8.64] in the lacnotuzumab + gem-carbo arm and 5.5 months (90% CI, 3.45-7.46) in the gem-carbo arm. Hematologic adverse events were common in both treatment arms; however, patients treated with lacnotuzumab experienced more frequent aspartate aminotransferase, alanine aminotransferase, and creatine kinase elevations. Pharmacokinetic results showed that free lacnotuzumab at 10 mg/kg exhibited a typical IgG pharmacokinetic profile and target engagement of circulating colony-stimulating factor 1 ligand. CONCLUSIONS: Despite successful target engagement and anticipated pharmacokinetic profile, lacnotuzumab + gem-carbo showed comparable antitumor activity to gem-carbo alone, with slightly poorer tolerability. However, the data presented in this article would be informative for future studies testing agents targeting the CSF1-CSF1 receptor pathway in TNBC.

Adjuvant Palbociclib for Early Breast Cancer: The PALLAS Trial Results (ABCSG-42/AFT-05/BIG-14-03).

PURPOSE: Palbociclib is a cyclin-dependent kinase 4 and 6 inhibitor approved for advanced breast cancer. In the adjuvant setting, the potential value of adding palbociclib to endocrine therapy for hormone receptor-positive breast cancer has not been confirmed. PATIENTS AND METHODS: In the prospective, randomized, phase III PALLAS trial, patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative early breast cancer were randomly assigned to receive 2 years of palbociclib (125 mg orally once daily, days 1-21 of a 28-day cycle) with adjuvant endocrine therapy or adjuvant endocrine therapy alone (for at least 5 years). The primary end point of the study was invasive disease-free survival (iDFS); secondary end points were invasive breast cancer-free survival, distant recurrence-free survival, locoregional cancer-free survival, and overall survival. RESULTS: Among 5,796 patients enrolled at 406 centers in 21 countries worldwide over 3 years, 5,761 were included in the intention-to-treat population. At the final protocol-defined analysis, at a median follow-up of 31 months, iDFS events occurred in 253 of 2,884 (8.8%) patients who received palbociclib plus endocrine therapy and in 263 of 2,877 (9.1%) patients who received endocrine therapy alone, with similar results between the two treatment groups (iDFS at 4 years: 84.2% v 84.5%; hazard ratio, 0.96; CI, 0.81 to 1.14; P = .65). No significant differences were observed for secondary time-to-event end points, and subgroup analyses did not show any differences by subgroup. There were no new safety signals for palbociclib in this trial. CONCLUSION: At this final analysis of the PALLAS trial, the addition of adjuvant palbociclib to standard endocrine therapy did not improve outcomes over endocrine therapy alone in patients with early hormone receptor-positive breast cancer.

Androgen Receptor is Expressed in Breast Cancer Brain Metastases.

BACKGROUND: Androgen receptor (AR) expression is a potential therapeutic target in breast cancer (BC) as it is frequently expressed in the luminal A and B subtypes and in approximately one third of basal-like cancers. As AR-positive BC displays a distinct biological behavior, we aimed to analyze AR expression in the particular context of BC brain metastases (BM). MATERIALS AND METHODS: Patients with newly diagnosed BC BM treated with neurosurgical resection were identified from the Vienna Brain Metastasis Registry and clinical data including patient characteristics, biological tumor subtypes and overall survival were obtained by retrospective chart review. Formalin-fixed and paraffin-embedded specimen containing BM tissue were retrieved from the Neuro-Biobank. Immunohistochemical staining of AR was performed and AR expression in the tumor-cell nucleus was evaluated. RESULTS: Fifty-seven BM samples from 57 individual patients with BC were available for this analysis. AR expression of ≥1% tumor cells was evident in 20/57 (35.1%) BM specimens; the median AR-expression rate was 10% (range: 1% to 60%). AR expression was observed in 11/21 (52.4%) BM of the luminal/human epidermal growth factor receptor 2 (HER2)-negative subtype, 3/13 (23.1%) of the luminal/HER2-positive subtype, 2/7 (28.6%) of the HER2-positive subtype and 4/16 (25.0%) of the triple-negative subtype (P=0.247). Median survival from diagnosis of BM was 10 months (range: 0 to 104 mo) in the entire cohort. No significant association of overall survival and AR expression ≥1% was observed (15 vs. 13 mo; P>0.05). CONCLUSION: AR is expressed in more than one third of BC BM with the highest rates among the luminal/HER2-negative BC subtype and may therefore be a potential prognostic and predictive biomarker in this particular BC population.

Triple-negative breast cancer.

Recent advances in biological characterization of breast cancer have eventually increased our understanding of underlying tumour biology. While for endocrine responsive and Her2-positive disease different molecular targeted therapies are available, up to now no specific targeted approach for triple-negative breast cancer has been developed. Patients with triple-negative disease are at high risk for tumour recurrence. Preclinical and limited clinical data suggest that platinum-based regimens may be the most active conventional chemotherapy, but prospective randomized trials are missing. Bevacizumab and other agents targeting tumour vessel growth have potential activity in all subtypes of breast cancer, and therefore are not considered a targeted approach for triple-negative tumours alone. Due to specific defects in DNA-damage repair, basal-like cancers depend on alternative, more error-prone repair pathways. Currently, scientific interest is focussing on drugs blocking those mechanisms. PARP-1 inhibitors, in conjunction with platinum derivatives, were found to exhibit significant survival benefit over chemotherapy alone even in a relatively small phase II study. For the first time, this approach offers the chance of highly active, specific therapy for triple-negative disease.