Summary Background Neratinib, an irreversible tyrosine-kinase inhibitor of HER1, HER2, and HER4, has clinical activity in patients with HER2-positive metastatic breast cancer. We aimed to investigate ...the efficacy and safety of 12 months of neratinib after trastuzumab-based adjuvant therapy in patients with early-stage HER2-positive breast cancer. Methods We did this multicentre, randomised, double-blind, placebo-controlled, phase 3 trial at 495 centres in Europe, Asia, Australia, New Zealand, and North and South America. Eligible women (aged ≥18 years, or ≥20 years in Japan) had stage 1–3 HER2-positive breast cancer and had completed neoadjuvant and adjuvant trastuzumab therapy up to 2 years before randomisation. Inclusion criteria were amended on Feb 25, 2010, to include patients with stage 2–3 HER2-positive breast cancer who had completed trastuzumab therapy up to 1 year previously. Patients were randomly assigned (1:1) to receive oral neratinib 240 mg per day or matching placebo. The randomisation sequence was generated with permuted blocks stratified by hormone receptor status (hormone receptor-positive oestrogen or progesterone receptor-positive or both vs hormone receptor-negative oestrogen and progesterone receptor-negative), nodal status (0, 1–3, or ≥4), and trastuzumab adjuvant regimen (sequentially vs concurrently with chemotherapy), then implemented centrally via an interactive voice and web-response system. Patients, investigators, and trial sponsors were masked to treatment allocation. The primary outcome was invasive disease-free survival, as defined in the original protocol, at 2 years after randomisation. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov , number NCT00878709. Findings Between July 9, 2009, and Oct 24, 2011, we randomly assigned 2840 women to receive neratinib (n=1420) or placebo (n=1420). Median follow-up time was 24 months (IQR 20–25) in the neratinib group and 24 months (22–25) in the placebo group. At 2 year follow-up, 70 invasive disease-free survival events had occurred in patients in the neratinib group versus 109 events in those in the placebo group (stratified hazard ratio 0·67, 95% CI 0·50–0·91; p=0·0091). The 2-year invasive disease-free survival rate was 93·9% (95% CI 92·4–95·2) in the neratinib group and 91·6% (90·0–93·0) in the placebo group. The most common grade 3–4 adverse events in patients in the neratinib group were diarrhoea (grade 3, n=561 40% and grade 4, n=1 <1% vs grade 3, n=23 2% in the placebo group), vomiting (grade 3, n=47 3% vs n=5 <1%), and nausea (grade 3, n=26 2% vs n=2 <1%). QT prolongation occurred in 49 (3%) patients given neratinib and 93 (7%) patients given placebo, and decreases in left ventricular ejection fraction (≥grade 2) in 19 (1%) and 15 (1%) patients, respectively. We recorded serious adverse events in 103 (7%) patients in the neratinib group and 85 (6%) patients in the placebo group. Seven (<1%) deaths (four patients in the neratinib group and three patients in the placebo group) unrelated to disease progression occurred after study drug discontinuation. The causes of death in the neratinib group were unknown (n=2), a second primary brain tumour (n=1), and acute myeloid leukaemia (n=1), and in the placebo group were a brain haemorrhage (n=1), myocardial infarction (n=1), and gastric cancer (n=1). None of the deaths were attributed to study treatment in either group. Interpretation Neratinib for 12 months significantly improved 2-year invasive disease-free survival when given after chemotherapy and trastuzumab-based adjuvant therapy to women with HER2-positive breast cancer. Longer follow-up is needed to ensure that the improvement in breast cancer outcome is maintained. Funding Wyeth, Pfizer, Puma Biotechnology.
Summary Background Postmenopausal women with hormone receptor-positive early breast cancer have persistent, long-term risk of breast-cancer recurrence and death. Therefore, trials assessing endocrine ...therapies for this patient population need extended follow-up. We present an update of efficacy outcomes in the Breast International Group (BIG) 1-98 study at 8·1 years median follow-up. Methods BIG 1-98 is a randomised, phase 3, double-blind trial of postmenopausal women with hormone receptor-positive early breast cancer that compares 5 years of tamoxifen or letrozole monotherapy, or sequential treatment with 2 years of one of these drugs followed by 3 years of the other. Randomisation was done with permuted blocks, and stratified according to the two-arm or four-arm randomisation option, participating institution, and chemotherapy use. Patients, investigators, data managers, and medical reviewers were masked. The primary efficacy endpoint was disease-free survival (events were invasive breast cancer relapse, second primaries contralateral breast and non-breast, or death without previous cancer event). Secondary endpoints were overall survival, distant recurrence-free interval (DRFI), and breast cancer-free interval (BCFI). The monotherapy comparison included patients randomly assigned to tamoxifen or letrozole for 5 years. In 2005, after a significant disease-free survival benefit was reported for letrozole as compared with tamoxifen, a protocol amendment facilitated the crossover to letrozole of patients who were still receiving tamoxifen alone; Cox models and Kaplan-Meier estimates with inverse probability of censoring weighting (IPCW) are used to account for selective crossover to letrozole of patients (n=619) in the tamoxifen arm. Comparison of sequential treatments to letrozole monotherapy included patients enrolled and randomly assigned to letrozole for 5 years, letrozole for 2 years followed by tamoxifen for 3 years, or tamoxifen for 2 years followed by letrozole for 3 years. Treatment has ended for all patients and detailed safety results for adverse events that occurred during the 5 years of treatment have been reported elsewhere. Follow-up is continuing for those enrolled in the four-arm option. BIG 1-98 is registered at clinicaltrials.gov NCT00004205. Findings 8010 patients were included in the trial, with a median follow-up of 8·1 years (range 0–12·4). 2459 were randomly assigned to monotherapy with tamoxifen for 5 years and 2463 to monotherapy with letrozole for 5 years. In the four-arm option of the trial, 1546 were randomly assigned to letrozole for 5 years, 1548 to tamoxifen for 5 years, 1540 to letrozole for 2 years followed by tamoxifen for 3 years, and 1548 to tamoxifen for 2 years followed by letrozole for 3 years. At a median follow-up of 8·7 years from randomisation (range 0–12·4), letrozole monotherapy was significantly better than tamoxifen, whether by IPCW or intention-to-treat analysis (IPCW disease-free survival HR 0·82 95% CI 0·74–0·92, overall survival HR 0·79 0·69–0·90, DRFI HR 0·79 0·68–0·92, BCFI HR 0·80 0·70–0·92; intention-to-treat disease-free survival HR 0·86 0·78–0·96, overall survival HR 0·87 0·77–0·999, DRFI HR 0·86 0·74–0·998, BCFI HR 0·86 0·76–0·98). At a median follow-up of 8·0 years from randomisation (range 0–11·2) for the comparison of the sequential groups with letrozole monotherapy, there were no statistically significant differences in any of the four endpoints for either sequence. 8-year intention-to-treat estimates (each with SE ≤1·1%) for letrozole monotherapy, letrozole followed by tamoxifen, and tamoxifen followed by letrozole were 78·6%, 77·8%, 77·3% for disease-free survival; 87·5%, 87·7%, 85·9% for overall survival; 89·9%, 88·7%, 88·1% for DRFI; and 86·1%, 85·3%, 84·3% for BCFI. Interpretation For postmenopausal women with endocrine-responsive early breast cancer, a reduction in breast cancer recurrence and mortality is obtained by letrozole monotherapy when compared with tamoxifen montherapy. Sequential treatments involving tamoxifen and letrozole do not improve outcome compared with letrozole monotherapy, but might be useful strategies when considering an individual patient's risk of recurrence and treatment tolerability. Funding Novartis, United States National Cancer Institute, International Breast Cancer Study Group.
Summary Background Prediction of response to anthracycline-based therapy for breast cancer is challenging. We aimed to assess the value of HER2 and TOP2A as predictive markers of response to ...anthracycline-based adjuvant therapy in patients with early breast cancer. Methods We did a meta-analysis of individual patient data from five randomised adjuvant trials that compared anthracycline-based regimens with cyclophosphamide, methotrexate, and fluorouracil (CMF) regimens. We assessed the status of HER2 and TOP2A genes with fluorescent in-situ hybridisation. Tumour samples were submitted to an external laboratory for validation. We calculated hazard ratios (HR) to compare event-free survival (EFS) and overall survival in patients receiving anthracycline-based treatment with those receiving CMF in two HER2 cohorts ( HER2 amplified and non-amplified tumours) and in three TOP2A cohorts (normal, amplified, and deleted tumours). Findings We analysed data for 3452 patients for HER2 and 3102 patients for TOP2A . For EFS, HRs were 0·89 (95% CI 0·79–1·01) for HER2 non-amplified patients and 0·71 (0·58–0·86) for HER2 -amplified patients (pinteraction =0·0485); for overall survival, HRs were 0·91 (95% CI 0·79–1·05) for HER2 non-amplified patients and 0·73 (0·59–0·89) for HER2 -amplified patients (pinteraction =0·0718). In analysis of TOP2A status, HRs for EFS were 0·88 (0·78–1·00) for normal, 0·63 (0·46–0·87) for deleted, and 0·62 (0·43–0·90) for amplified (pinteraction =0·0513); HRs for overall survival were 0·89 (0·78–1·03) for normal, 0·68 (0·49–0·95) for deleted, and 0·67 (0·46–0·98) for amplified (pinteraction =0·1608). When patients with TOP2A -deleted and TOP2A -amplified tumours were grouped together (altered cohort) and compared with data from patients with normal TOP2A tumours, HRs for EFS were 0·64 (0·50–0·81) for altered and 0·88 (0·78–1·00) for normal (pinteraction =0·0183); HRs for overall survival were 0·67 (0·52–0·86) for altered and 0·89 (0·78–1·03) for normal (pinteraction =0·0455). Interpretation Although HER2 amplification and combined TOP2A amplification and deletion may have some value in the prediction of responsiveness to anthracycline-based chemotherapy, our findings do not support the use of anthracyclines only in patients with HER2 -amplified or TOP2A -aberrated tumours. Funding Associazione Italiana Ricerca Cancro, Academy of Finland, Belgian Federation Against Cancer, Cancer Research UK, Les Amis de l'Institut Bordet, Scottish Breast Cancer Trials Group, NCIC Clinical Trials Group, Canadian Cancer Society Research Institute, Danish Council for Strategic Research, Pharmacia-Upjohn (now Pfizer), and Abbott Laboratories.
Summary Background Worldwide, many patients with HER2-positive early stage breast cancer do not receive trastuzumab—the standard adjuvant treatment. We investigated the efficacy and safety of ...adjuvant lapatinib for patients with trastuzumab-naive HER2-positive early-stage breast cancer, started at any time after diagnosis. Methods This study was a placebo-controlled, multicentre, randomised phase 3 trial. Women outpatients from 405 centres in 33 countries with HER2-positive early-breast cancer who had previously received adjuvant chemotherapy but not trastuzumab were randomly assigned (1:1) to receive daily lapatinib (1500 mg) or daily placebo for 12 months. Randomisation was done with a computer-generated sequence, stratified by time since diagnosis, lymph node involvement at diagnosis, and tumour hormone-receptor status. Investigators, site staff, and patients were masked to treatment assignment. The primary endpoint was disease-free survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov , number NCT00374322. Findings Between August, 2006, and May, 2008, 3161 women were enrolled and 3147 were assigned to lapatinib (n=1571) or placebo (n=1576). After a median follow-up of 47·4 months (range 0·4–60·0) in the lapatinib group and 48·3 (0·7–61·3) in the placebo group, 210 (13%) disease-free survival events had occurred in the lapatinib group versus 264 (17%) in the placebo group (hazard ratio HR 0·83, 95% CI 0·70–1·00; p=0·053). Central review of HER2 status showed that only 2490 (79%) of the randomised women were HER2-positive. 157 (13%) of 1230 confirmed HER2-positive patients in the lapatinib group and in 208 (17%) of 1260 in the placebo group had a disease-free survival event (HR 0·82, 95% 0·67–1·00; p=0·04). Serious adverse events occurred in 99 (6%) of 1573 patients taking lapatinib and 77 (5%) of 1574 patients taking placebo, with higher incidences of grade 3–4 diarrhoea (97 6% vs nine <1%), rash (72 5% vs three <1%), and hepatobiliary disorders (36 2% vs one <1%). Interpretation Our data show that there was no significant difference in disease-free survival between groups when analysed in the intention-to-treat population. However, exploratory analyses restricted to patients who had HER2-positive disease confirmed by central fluorescence in-situ hybridisation review suggested marginal benefit with lapatinib in terms of disease-free survival. Thus lapatinib might be an option for women with HER2-positive breast cancer who do not or cannot receive adjuvant trastuzumab. Funding GlaxoSmithKline.
Abstract Purpose Tamoxifen reduces the risk of contralateral breast cancer (CBC), but little is known about the long-term risk. Methods From the database under the Danish Breast Cancer Cooperative ...Group (DBCG), we identified 15,863 users and 21,670 nonusers of tamoxifen among women diagnosed with breast cancer during 1977 to 2007. Information on CBC was obtained from the Danish Cancer Registry and the Danish Breast Cancer Cooperative Group database. Cox regression analyses were carried out with estimation of hazard ratios (HRs) of CBC. We also estimated the HRs of current and past use of tamoxifen. Results Current use of tamoxifen was associated with reduced HRs of CBC independently of menopausal status and calendar-period. The HRs associated with past use of tamoxifen, however, varied among postmenopausal users from 1.50 (95% confidence interval CI, 1.20–1.87) among users in 1977 to 1989 to 0.87 (95% CI, 0.70–1.06) and 1.05 (95% CI, 0.68–1.63) among users in 1990 to 1998 and 1999 to 2007, respectively. No excesses or deficits of CBC were found 10 or more years since the last use in postmenopausal women in any calendar-period. Conclusions Our study confirms that tamoxifen protects against CBC while being treated. The effect of tamoxifen after cessation of treatment was not clear because of the inconsistency in results by calendar-period.
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