Summary Background Pathological complete response has been proposed as a surrogate endpoint for prediction of long-term clinical benefit, such as disease-free survival, event-free survival (EFS), and ...overall survival (OS). We had four key objectives: to establish the association between pathological complete response and EFS and OS, to establish the definition of pathological complete response that correlates best with long-term outcome, to identify the breast cancer subtypes in which pathological complete response is best correlated with long-term outcome, and to assess whether an increase in frequency of pathological complete response between treatment groups predicts improved EFS and OS. Methods We searched PubMed, Embase, and Medline for clinical trials of neoadjuvant treatment of breast cancer. To be eligible, studies had to meet three inclusion criteria: include at least 200 patients with primary breast cancer treated with preoperative chemotherapy followed by surgery; have available data for pathological complete response, EFS, and OS; and have a median follow-up of at least 3 years. We compared the three most commonly used definitions of pathological complete response—ypT0 ypN0, ypT0/is ypN0, and ypT0/is—for their association with EFS and OS in a responder analysis. We assessed the association between pathological complete response and EFS and OS in various subgroups. Finally, we did a trial-level analysis to assess whether pathological complete response could be used as a surrogate endpoint for EFS or OS. Findings We obtained data from 12 identified international trials and 11 955 patients were included in our responder analysis. Eradication of tumour from both breast and lymph nodes (ypT0 ypN0 or ypT0/is ypN0) was better associated with improved EFS (ypT0 ypN0: hazard ratio HR 0·44, 95% CI 0·39–0·51; ypT0/is ypN0: 0·48, 0·43–0·54) and OS (0·36, 0·30–0·44; 0·36, 0·31–0·42) than was tumour eradication from the breast alone (ypT0/is; EFS: HR 0·60, 95% CI 0·55–0·66; OS 0·51, 0·45–0·58). We used the ypT0/is ypN0 definition for all subsequent analyses. The association between pathological complete response and long-term outcomes was strongest in patients with triple-negative breast cancer (EFS: HR 0·24, 95% CI 0·18–0·33; OS: 0·16, 0·11–0·25) and in those with HER2-positive, hormone-receptor-negative tumours who received trastuzumab (EFS: 0·15, 0·09–0·27; OS: 0·08, 0·03, 0·22). In the trial-level analysis, we recorded little association between increases in frequency of pathological complete response and EFS ( R2 =0·03, 95% CI 0·00–0·25) and OS ( R2 =0·24, 0·00–0·70). Interpretation Patients who attain pathological complete response defined as ypT0 ypN0 or ypT0/is ypN0 have improved survival. The prognostic value is greatest in aggressive tumour subtypes. Our pooled analysis could not validate pathological complete response as a surrogate endpoint for improved EFS and OS. Funding US Food and Drug Administration.
Summary Background Adjuvant endocrine therapy compromises bone health in patients with breast cancer, causing osteopenia, osteoporosis, and fractures. Antiresorptive treatments such as ...bisphosphonates prevent and counteract these side-effects. In this trial, we aimed to investigate the effects of the anti-RANK ligand antibody denosumab in postmenopausal, aromatase inhibitor-treated patients with early-stage hormone receptor-positive breast cancer. Methods In this prospective, double-blind, placebo-controlled, phase 3 trial, postmenopausal patients with early hormone receptor-positive breast cancer receiving treatment with aromatase inhibitors were randomly assigned in a 1:1 ratio to receive either denosumab 60 mg or placebo administered subcutaneously every 6 months in 58 trial centres in Austria and Sweden. Patients were assigned by an interactive voice response system. The randomisation schedule used a randomly permuted block design with block sizes 2 and 4, stratified by type of hospital regarding Hologic device for DXA scans, previous aromatase inhibitor use, and baseline bone mineral density. Patients, treating physicians, investigators, data managers, and all study personnel were masked to treatment allocation. The primary endpoint was time from randomisation to first clinical fracture, analysed by intention to treat. As an additional sensitivity analysis, we also analysed the primary endpoint on the per-protocol population. Patients were treated until the prespecified number of 247 first clinical fractures was reached. This trial is ongoing (patients are in follow-up) and is registered with the European Clinical Trials Database, number 2005-005275-15, and with ClinicalTrials.gov , number NCT00556374. Findings Between Dec 18, 2006, and July 22, 2013, 3425 eligible patients were enrolled into the trial, of whom 3420 were randomly assigned to receive denosumab 60 mg (n=1711) or placebo (n=1709) subcutaneously every 6 months. Compared with the placebo group, patients in the denosumab group had a significantly delayed time to first clinical fracture (hazard ratio HR 0·50 95% CI 0·39–0·65, p<0·0001). The overall lower number of fractures in the denosumab group (92) than in the placebo group (176) was similar in all patient subgroups, including in patients with a bone mineral density T-score of −1 or higher at baseline (n=1872, HR 0·44 95% CI 0·31–0·64, p<0·0001) and in those with a bone mineral density T-score of less than −1 already at baseline (n=1548, HR 0·57 95% CI 0·40–0·82, p=0·002). The patient incidence of adverse events in the safety analysis set (all patients who received at least one dose of study drug) did not differ between the denosumab group (1366 events, 80%) and the placebo group (1334 events, 79%), nor did the numbers of serious adverse events (521 vs 511 30% in each group). The main adverse events were arthralgia and other aromatase-inhibitor related symptoms; no additional toxicity from the study drug was reported. Despite proactive adjudication of every potential osteonecrosis of the jaw by an international expert panel, no cases of osteonecrosis of the jaw were reported. 93 patients (3% of the full analysis set) died during the study, of which one death (in the denosumab group) was thought to be related to the study drug. Interpretation Adjuvant denosumab 60 mg twice per year reduces the risk of clinical fractures in postmenopausal women with breast cancer receiving aromatase inhibitors, and can be administered without added toxicity. Since a main side-effect of adjuvant breast cancer treatment can be substantially reduced by the addition of denosumab, this treatment should be considered for clinical practice. Funding Amgen.
Summary Background Trastuzumab—a humanised monoclonal antibody against HER2—has been shown to improve disease-free survival after chemotherapy in women with HER2-positive early breast cancer. We ...investigated the drug's effect on overall survival after a median follow-up of 2 years in the Herceptin Adjuvant (HERA) study. Methods HERA is an international multicentre randomised trial that compared 1 or 2 years of trastuzumab treatment with observation alone after standard neoadjuvant or adjuvant chemotherapy in women with HER2-positive node positive or high-risk node negative breast cancer. 5102 women participated in the trial; we analysed data from 1703 women who had been randomised for treatment with trastuzumab for 1 year and 1698 women from the control group, with median follow-up of 23·5 months (range 0–48 months). The primary endpoint of the trial was disease-free survival. Here, we assess overall survival, a secondary endpoint. Analyses were done on an intent-to-treat basis. This trial is registered with the European Clinical Trials Database, number 2005–002385–11. Findings 97 (5·7%) patients randomised to observation alone and 58 (3·4%) patients randomised to 1 year of treatment with trastuzumab were lost to follow-up. 172 women stopped trastuzumab prematurely. 59 deaths were reported for trastuzumab and 90 in the control group. The unadjusted hazard ratio (HR) for the risk of death with trastuzumab compared with observation alone was 0·66 (95% CI 0·47–0·91; p=0·0115). 218 disease-free survival events were reported with trastuzumab compared with 321 in the control group. The unadjusted HR for the risk of an event with trastuzumab compared with observation alone was 0·64 (0·54–0·76; p<0·0001). Interpretation Our results show that 1 year of treatment with trastuzumab after adjuvant chemotherapy has a significant overall survival benefit after a median follow-up of 2 years. The emergence of this benefit after only 2 years reinforces the importance of trastuzumab in the treatment of women with HER2-positive early breast cancer.
Summary Background TP53 has a crucial role in the DNA damage response. We therefore tested the hypothesis that taxanes confer a greater advantage than do anthracyclines on breast cancers with mutated ...TP53 than in those with wild-type TP53. Methods In an open-label, phase 3 study, women (age <71 years) with locally advanced, inflammatory, or large operable breast cancers were randomly assigned in a 1:1 ratio to either a standard anthracycline regimen (six cycles of intravenous fluorouracil 500 mg/m2 , epirubicin 100 mg/m2 , and cyclophosphamide 500 mg/m2 every 21 days FEC100, or fluorouracil 600 mg/m2 , epirubicin 75 mg/m2 , cyclophosphamide 900 mg/m2 tailored FEC starting on day 1 and then every 21 days) or a taxane-based regimen (three cycles of docetaxel 100 mg/m2 , intravenously infused over 1 h on day 1 every 21 days, followed by three cycles of intravenous epirubicin 90 mg/m2 and docetaxel 75 mg/m2 on day 1 every 21 days T-ET) at 42 centres in Europe. Randomisation was by use of a minimisation method that stratified patients by institution and initial tumour stage. The primary endpoint was progression-free survival (PFS) according to TP53 status. Analysis was by intention to treat. This is the final analysis of this trial. The study is registered with ClinicalTrials.gov , number NCT00017095. Findings 928 patients were enrolled in the FEC group and 928 in the T-ET group. TP53 status was not assessable for 183 (20%) patients in the FEC group and 204 (22%) patients in the T-ET group mainly because of low tumour-cell content in the biopsy. 361 primary endpoint events were recorded in the FEC group and 314 in the T-ET group. In patients with TP53 -mutated tumours, 5-year PFS was 59·5% (95% CI 53·4–65·1) in the T-ET group (n=326) and 55·3% (49·2–60·9) in the FEC group (n=318; hazard ratio 0·84, 98% CI 0·63–1·14; p=0·17). In patients with TP53 wild-type tumours, 5-year PFS was 66·8% (95% CI 61·4–71·6) in the T-ET group (n=398) and 64·7% (59·6–69·4) in the FEC group (n=427; 0·89, 98% CI 0·68–1·18; p=0·35). For all patients, irrespective of TP53 status, 5-year PFS was 65·1% (95% CI 61·6–68·3) in the T-ET group and 60·8% (57·3–64·2) in the FEC group (0·85, 98% CI 0·71–1·02; p=0·035). At the sites using FEC100 versus T-ET, the most common grade 3 or 4 adverse events were febrile neutropenia (75 9% of 803 vs 173 21% of 809, respectively), and neutropenia (653 81% vs 730 90%, respectively). At the sites using tailored FEC versus T-ET, the most common grade 3 or 4 adverse events were febrile neutropenia (ten 8% of 118 vs 26 22% of 116, respectively), and neutropenia (100 85% vs 115 99%, respectively). Two patients died of toxicity during or within 30 days of chemotherapy completion and without disease relapse (one in each group). Interpretation Although TP53 status was prognostic for overall survival, it was not predictive of preferential sensitivity to taxanes. TP53 status tested by use of the yeast assay in this patient population cannot be used to select patients for an anthracycline-based chemotherapy versus a taxane-based chemotherapy. Funding US National Cancer Institute, La Ligue Nationale Contre le Cancer, European Union, Pharmacia, and Sanofi-Aventis.
Summary Background We have previously described gene-expression signatures that predict growth inhibitory and cytotoxic effects of common chemotherapeutic drugs in vitro. The aim of this study was to ...confirm the validity of these gene-expression signatures in a large series of patients with oestrogen-receptor-negative breast tumours who were treated in a phase III neoadjuvant clinical trial. Methods This trial compares a non-taxane regimen (fluorouracil, epirubicin, and cyclophosphamide FEC for six cycles) with a taxane regimen (docetaxel for three cycles followed by epirubicin plus docetaxel TET for three cycles) in women with oestrogen-receptor-negative breast cancer. The primary endpoint of the study is the difference in progression-free survival based on TP53 status and will be reported later. Predicting response with gene signatures was a planned secondary endpoint of the trial and is reported here. Pathological complete response, defined as complete disappearance of the tumour with no more than a few scattered tumour cells detected by the pathologist in the resection specimen, was used to assess chemosensitivity. RNA was prepared from sections of frozen biopsies taken at diagnosis and hybridised to Affymetrix X3P microarrays. In-vitro single-agent drug sensitivity signatures were combined to obtain FEC and TET regimen-specific signatures. This study is registered on the clinical trials site of the US National Cancer Institute website http://www.clinicaltrials.gov/ct/show/NCT00017095. Findings Of 212 patients with oestrogen-receptor-negative tumours assessed, 87 patients were excluded. 125 oestrogen-receptor-negative tumours (55 that showed pathological complete responses) were tested: 66 in the FEC group (28 that showed pathological complete responses) and 59 in the TET group (27 that showed pathological complete responses). The regimen-specific signatures significantly predicted pathological complete response in patients treated with the appropriate regimen (p<0·0001). The FEC predictor had a sensitivity of 96% (27 of 28 patients 95% CI 82–99), specificity of 66% (25 of 38 patients 50–79), positive predictive value (PPV) of 68% (27 of 40 patients 52–80), and negative predictive value (NPV) of 96% (25 of 26 patients 81–99). The TET predictor had a sensitivity of 93% (25 of 27 patients 77–98), specificity 69% (22 of 32 patients 51–82), PPV of 71% (25 of 35 patients 55–84), and NPV of 92% (22 of 24 patients 74–98). Analysis of tumour size, grade, nodal status, age, and regimen-specific signatures showed that the genomic signatures were the only independent variables predicting pathological complete response at p<0·01. Selection of patients with these signatures would increase the proportion of patients with pathological complete responses from 44% to around 70% in the patients studied here. Interpretation We have validated the use of regimen-specific drug sensitivity signatures in the context of a multicentre randomised trial. The high NPV of both signatures may allow early selection of patients with breast cancer who should be considered for trials with new drugs.
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