Ana Lluch

Randomized Phase II Trial of the Efficacy and Safety of Trastuzumab Combined With Docetaxel in Patients With Human Epidermal Growth Factor Receptor 2–Positive Metastatic Breast Cancer Administered As First-Line Treatment: The M77001 Study Group

PURPOSE This randomized, multicenter trial compared first-line trastuzumab plus docetaxel versus docetaxel alone in patients with human epidermal growth factor receptor 2 (HER2) -positive metastatic breast cancer (MBC). PATIENTS AND METHODS Patients were randomly assigned to six cycles of docetaxel 100 mg/m2 every 3 weeks, with or without trastuzumab 4 mg/kg loading dose followed by 2 mg/kg weekly until disease progression. RESULTS A total of 186 patients received at least one dose of the study drug. Trastuzumab plus docetaxel was significantly superior to docetaxel alone in terms of overall response rate (61% v 34%; P = .0002), overall survival (median, 31.2 v 22.7 months; P = .0325), time to disease progression (median, 11.7 v 6.1 months; P = .0001), time to treatment failure (median, 9.8 v 5.3 months; P = .0001), and duration of response (median, 11.7 v 5.7 months; P = .009). There was little difference in the number and severity of adverse events between the arms. Grade 3 to 4 neutropenia was seen more commonly with the combination (32%) than with docetaxel alone (22%), and there was a slightly higher incidence of febrile neutropenia in the combination arm (23% v 17%). One patient in the combination arm experienced symptomatic heart failure (1%). Another patient experienced symptomatic heart failure 5 months after discontinuation of trastuzumab because of disease progression, while being treated with an investigational anthracycline for 4 months. CONCLUSION Trastuzumab combined with docetaxel is superior to docetaxel alone as first-line treatment of patients with HER2-positive MBC in terms of overall survival, response rate, response duration, time to progression, and time to treatment failure, with little additional toxicity.

Efficacy and safety of neoadjuvant pertuzumab and trastuzumab in women with locally advanced, inflammatory, or early HER2-positive breast cancer (NeoSphere): a randomised multicentre, open-label, phase 2 trial

BACKGROUND Studies with pertuzumab, a novel anti-HER2 antibody, show improved efficacy when combined with the established HER2-directed antibody trastuzumab in breast cancer therapy. We investigated the combination of pertuzumab or trastuzumab, or both, with docetaxel and the combination of pertuzumab and trastuzumab without chemotherapy in the neoadjuvant setting. METHODS In this multicentre, open-label, phase 2 study, treatment-naive women with HER2-positive breast cancer were randomly assigned (1:1:1:1) centrally and stratified by operable, locally advanced, and inflammatory breast cancer, and by hormone receptor expression to receive four neoadjuvant cycles of: trastuzumab (8 mg/kg loading dose, followed by 6 mg/kg every 3 weeks) plus docetaxel (75 mg/m(2), escalating, if tolerated, to 100 mg/m(2) every 3 weeks; group A) or pertuzumab (loading dose 840 mg, followed by 420 mg every 3 weeks) and trastuzumab plus docetaxel (group B) or pertuzumab and trastuzumab (group C) or pertuzumab plus docetaxel (group D). The primary endpoint, examined in the intention-to-treat population, was pathological complete response in the breast. Neither patients nor investigators were masked to treatment. This study is registered with ClinicalTrials.gov, number NCT00545688. FINDINGS Of 417 eligible patients, 107 were randomly assigned to group A, 107 to group B, 107 to group C, and 96 to group D. Patients given pertuzumab and trastuzumab plus docetaxel (group B) had a significantly improved pathological complete response rate (49 of 107 patients; 45·8% [95% CI 36·1-55·7]) compared with those given trastuzumab plus docetaxel (group A; 31 of 107; 29·0% [20·6-38·5]; p=0·0141). 23 of 96 (24·0% [15·8-33·7]) women given pertuzumab plus docetaxel (group D) had a pathological complete response, as did 18 of 107 (16·8% [10·3-25·3]) given pertuzumab and trastuzumab (group C). The most common adverse events of grade 3 or higher were neutropenia (61 of 107 women in group A, 48 of 107 in group B, one of 108 in group C, and 52 of 94 in group D), febrile neutropenia (eight, nine, none, and seven, respectively), and leucopenia (13, five, none, and seven, respectively). The number of serious adverse events was similar in groups A, B, and D (15-20 serious adverse events per group in 10-17% of patients) but lower in group C (four serious adverse events in 4% of patients). INTERPRETATION Patients given pertuzumab and trastuzumab plus docetaxel (group B) had a significantly improved pathological complete response rate compared with those given trastuzumab plus docetaxel, without substantial differences in tolerability. Pertuzumab and trastuzumab without chemotherapy eradicated tumours in a proportion of women and showed a favourable safety profile. These findings justify further exploration in adjuvant trials and support the neoadjuvant approach for accelerating drug assessment in early breast cancer. FUNDING F Hoffmann-La Roche.

Neoadjuvant chemotherapy with trastuzumab followed by adjuvant trastuzumab versus neoadjuvant chemotherapy alone, in patients with HER2-positive locally advanced breast cancer (the NOAH trial): a randomised controlled superiority trial with a parallel HER2-negative cohort

BACKGROUND The monoclonal antibody trastuzumab has survival benefit when given with chemotherapy to patients with early, operable, and metastatic breast cancer that has HER2 (also known as ERBB2) overexpression or amplification. We aimed to assess event-free survival in patients with HER2-positive locally advanced or inflammatory breast cancer receiving neoadjuvant chemotherapy with or without 1 year of trastuzumab. METHODS We compared 1 year of treatment with trastuzumab (given as neoadjuvant and adjuvant treatment; n=117) with no trastuzumab (118), in women with HER2-positive locally advanced or inflammatory breast cancer treated with a neoadjuvant chemotherapy regimen consisting of doxorubicin, paclitaxel, cyclophosphamide, methotrexate, and fluorouracil. Randomisation was done with a computer program and minimisation technique, taking account of geographical area, disease stage, and hormone receptor status. Investigators were informed of treatment allocation. A parallel cohort of 99 patients with HER2-negative disease was included and treated with the same chemotherapy regimen. Primary endpoint was event-free survival. Analysis was by intention to treat. This study is registered, number ISRCTN86043495. FINDINGS Trastuzumab significantly improved event-free survival in patients with HER2-positive breast cancer (3-year event-free survival, 71% [95% CI 61-78; n=36 events] with trastuzumab, vs 56% [46-65; n=51 events] without; hazard ratio 0.59 [95% CI 0.38-0.90]; p=0.013). Trastuzumab was well tolerated and, despite concurrent administration with doxorubicin, only two patients (2%) developed symptomatic cardiac failure. Both responded to cardiac drugs. INTERPRETATION The addition of neoadjuvant and adjuvant trastuzumab to neoadjuvant chemotherapy should be considered for women with HER2-positive locally advanced or inflammatory breast cancer to improve event-free survival, survival, and clinical and pathological tumour responses. FUNDING F Hoffmann-La Roche.

An Integrative Genomic and Proteomic Analysis of PIK3CA, PTEN, and AKT Mutations in Breast Cancer

Phosphatidylinositol 3-kinase (PI3K)/AKT pathway aberrations are common in cancer. By applying mass spectroscopy-based sequencing and reverse-phase protein arrays to 547 human breast cancers and 41 cell lines, we determined the subtype specificity and signaling effects of PIK3CA, AKT, and PTEN mutations and the effects of PIK3CA mutations on responsiveness to PI3K inhibition in vitro and on outcome after adjuvant tamoxifen. PIK3CA mutations were more common in hormone receptor-positive (34.5%) and HER2-positive (22.7%) than in basal-like tumors (8.3%). AKT1 (1.4%) and PTEN (2.3%) mutations were restricted to hormone receptor-positive cancers. Unlike AKT1 mutations that were absent from cell lines, PIK3CA (39%) and PTEN (20%) mutations were more common in cell lines than tumors, suggesting a selection for these but not AKT1 mutations during adaptation to culture. PIK3CA mutations did not have a significant effect on outcome after adjuvant tamoxifen therapy in 157 hormone receptor-positive breast cancer patients. PIK3CA mutations, in comparison with PTEN loss and AKT1 mutations, were associated with significantly less and inconsistent activation of AKT and of downstream PI3K/AKT signaling in tumors and cell lines. PTEN loss and PIK3CA mutation were frequently concordant, suggesting different contributions to pathophysiology. PTEN loss rendered cells significantly more sensitive to growth inhibition by the PI3K inhibitor LY294002 than did PIK3CA mutations. Thus, PI3K pathway aberrations likely play a distinct role in the pathogenesis of different breast cancer subtypes. The specific aberration present may have implications for the selection of PI3K-targeted therapies in hormone receptor-positive breast cancer.

AKT-independent signaling downstream of oncogenic PIK3CA mutations in human cancer

Dysregulation of the phosphatidylinositol 3-kinase (PI3K) signaling pathway occurs frequently in human cancer. PTEN tumor suppressor or PIK3CA oncogene mutations both direct PI3K-dependent tumorigenesis largely through activation of the AKT/PKB kinase. However, here we show through phosphoprotein profiling and functional genomic studies that many PIK3CA mutant cancer cell lines and human breast tumors exhibit only minimal AKT activation and a diminished reliance on AKT for anchorage-independent growth. Instead, these cells retain robust PDK1 activation and membrane localization and exhibit dependency on the PDK1 substrate SGK3. SGK3 undergoes PI3K- and PDK1-dependent activation in PIK3CA mutant cancer cells. Thus, PI3K may promote cancer through both AKT-dependent and AKT-independent mechanisms. Knowledge of differential PI3K/PDK1 signaling could inform rational therapeutics in cancers harboring PIK3CA mutations.

Phase II and Tumor Pharmacodynamic Study of Gefitinib in Patients with Advanced Breast Cancer

PURPOSE To evaluate the antitumor activity and pharmacodynamic/biologic effect of gefitinib 500 mg/day monotherapy in patients with previously treated, advanced breast cancer. METHODS In this phase II multicenter trial, the primary objective was assessment of the tumor response rate with gefitinib; secondary objectives included analysis of the pharmacodynamic and biologic profiles in healthy and tumor tissue. RESULTS while phosphorylation of mitogen-activated protein kinase was inhibited in both tissues, gefitinib treatment induced p27 and a decrease in Ki67 in skin but not in tumors. Furthermore, gefitinib did not inhibit the activated form of Akt in the tumors. CONCLUSION This study demonstrates a good correlation between the degree of inhibition of EGFR in skin and in breast tumors. The lack of significant clinical activity of gefitinib in our study population is not due to lack of receptor inhibition in these tumors but rather to lack of EGFR dependence in the tested population.

A Genomic Predictor of Response and Survival Following Taxane-Anthracycline Chemotherapy for Invasive Breast Cancer

CONTEXT Prediction of high probability of survival from standard cancer treatments is fundamental for individualized cancer treatment strategies. OBJECTIVE To develop a predictor of response and survival from chemotherapy for newly diagnosed invasive breast cancer. DESIGN, SETTING, AND PATIENTS Prospective multicenter study conducted from June 2000 to March 2010 at the M. D. Anderson Cancer Center to develop and test genomic predictors for neoadjuvant chemotherapy. Patients were those with newly diagnosed ERBB2 (HER2 or HER2/neu)-negative breast cancer treated with chemotherapy containing sequential taxane and anthracycline-based regimens (then endocrine therapy if estrogen receptor [ER]-positive). Different predictive signatures for resistance and response to preoperative (neoadjuvant) chemotherapy (stratified according to ER status) were developed from gene expression microarrays of newly diagnosed breast cancer (310 patients). Breast cancer treatment sensitivity was then predicted using the combination of signatures for (1) sensitivity to endocrine therapy, (2) chemoresistance, and (3) chemosensitivity, with independent validation (198 patients) and comparison with other reported genomic predictors of chemotherapy response. MAIN OUTCOME MEASURES Distant relapse-free survival (DRFS) if predicted treatment sensitive and absolute risk reduction ([ARR], difference in DRFS between 2 predicted groups) at median follow-up (3 years). RESULTS Patients in the independent validation cohort (99% clinical stage II-III) who were predicted to be treatment sensitive (28%) had 56% (95% CI, 31%-78%) probability of excellent pathologic response and DRFS of 92% (95% CI, 85%-100%), with an ARR of 18% (95% CI, 6%-28%). Survival was predicted in ER-positive (30% predicted sensitive; DRFS, 97% [95% CI, 91%-100%]; ARR, 11% [95% CI, 0.1%-21%]) and ER-negative (26% predicted sensitive; DRFS, 83% [95% CI, 68%-100%]; ARR, 26% [95% CI, 4%-48%]) subsets and was significant in multivariate analysis. Other genomic predictors showed paradoxically worse survival for patients predicted to be responsive to chemotherapy. CONCLUSION A genomic predictor combining ER status, predicted chemoresistance, predicted chemosensitivity, and predicted endocrine sensitivity identified patients with high probability of survival following taxane and anthracycline chemotherapy.

Phase II Clinical Trial of Ixabepilone (BMS-247550), an Epothilone B Analog, in Patients With Taxane-Resistant Metastatic Breast Cancer

PURPOSE Ixabepilone (BMS-247550) is an epothilone analog that optimizes the properties of naturally occurring epothilone B. Natural epothilones and their analogs promote tumor cell death by binding to tubulin and stabilizing microtubules, causing apoptosis. This international phase II trial assessed the activity of ixabepilone in patients with metastatic breast cancer (MBC) that was resistant to taxane therapy. PATIENTS AND METHODS MBC patients, who had experienced disease progression while receiving or within 4 months of taxane therapy (6 months if adjuvant taxane only), and who had a taxane as their last regimen, received ixabepilone (1- or 3-hour infusion of 50 mg/m(2) or 3-hour infusion of 40 mg/m(2) every 3 weeks). RESULTS Of 49 patients treated with 40 mg/m(2) ixabepilone during 3 hours, 35 (73%) had experienced disease progression within 1 month of their last taxane dose. The response rate was 12% (95% CI, 4.7% to 26.5%). All responses (n = 6) were partial; five of six patients had not responded to prior taxane therapy. In responders, the median response duration was 10.4 months. In 20 patients (41%), stable disease was the best outcome. Median time to progression was 2.2 months (95% CI, 1.4 to 3.2 months); median survival was 7.9 months. For treated patients across all cohorts (intent-to-treat population), the response rate was also 12% (eight of 66). Treatment-related adverse events in the study were manageable and primarily grade 1/2. Treatment-related neuropathy was mostly sensory and mild to moderate. CONCLUSION Ixabepilone (40 mg/m(2) as a 3-hour infusion every 3 weeks) demonstrates promising antitumor activity and an acceptable safety profile in patients with taxane-resistant MBC.

Molecular biology in breast cancer: intrinsic subtypes and signaling pathways.

The last decade has brought a breakthrough in the knowledge of the biology of breast cancer. The technological development, and in particular the high throughput technologies, have allowed researchers to inquire more deeply into the nature of the disease through the comparative study of large numbers of samples. The classification of breast cancer by traditional parameters has been joined by rankings based on gene expression. Among the most popular platforms are MammaPrint®, Oncotype DX® the wound-response model, the rate of two genes model, the genomic grade index and the intrinsic subtype model. The latter one provides the amplest biological information and allows for the classification of breast cancer into six intrinsic subtypes: luminal A, luminal B, HER2-enriched, basal-like, normal breast and claudin-low. These new classifications are not yet fully applicable to clinical practice not only because they have not been standardized, but also because they entail a substantial economic outlay. Nevertheless, they have provided valuable information on tumor biology that has led to a better understanding of the signaling pathways governing the processes of formation, maintenance and expansion of the tumors. Researchers now know more about the HER2, estrogen receptor, IGF1R, PI3K/AKT, mTOR, AMPK and angiogenesis pathways which has allowed for the development of new targeted therapeutics now being tested in ongoing clinical trials. In general, one can say that the last decade has changed the way researchers understand, classify and study breast cancer, and it has reshaped the way doctors diagnose and treat this disease. In addition, it has undoubtedly changed the search for alternative therapies by integrating molecular studies and the selection of study populations based on their molecular markers into clinical trials. The present review summarizes the advances that have allowed researchers to both better classify the disease, as well as explore some of the most important signaling pathways.

p95HER-2 Predicts Worse Outcome in Patients with HER-2-Positive Breast Cancer

Background: The HER-2 receptor undergoes a proteolytic cleavage generating an NH2-terminally truncated fragment, p95HER-2, that is membrane-associated and tyrosine-phosphorylated. We have reported that p95HER-2, but not the full-length receptor, p185HER-2, correlated with the extent of lymph node involvement in patients with breast cancer and its expression was significantly enhanced in nodal metastatic tissue. These facts suggested an important role for p95HER-2 either as a marker or cause of metastasis and poor outcome in breast cancer. In this work, we have studied the prognostic value of p95HER-2 in breast cancer. Methods: Primary breast tumor tissues (n = 483) were from surgical resections conducted in hospitals in two different countries: the U.S. (n = 334) and Spain (n = 149). HER-2 protein forms, including p185HER-2 and p95HER-2, were examined in extracts of primary breast tumors by Western blot analysis. The levels of the two forms (high or low) were tested for association with other clinicopathologic factors and for correlation with disease-free survival. Results: The median follow-up was 46 months. A high level of p95HER-2 in primary tumor tissue correlated with reduced 5-year disease-free survival (hazard ratio, 2.55; 95% confidence interval, 2.13-8.01; P < 0.0001). The median time for disease-free survival was 32 versus 139 months in patients with low levels of p95HER-2. In comparison, high levels of the full-length p185HER-2 did not significantly correlate with poor outcome (P > 0.1). Multivariate analysis revealed that high p95HER-2 was an independent predictor of disease-free survival (hazard ratio, 1.59; 95% confidence interval, 1.246-1.990; P = 0.0004). Conclusions: p95HER-2 expression is an independent prognostic factor in breast cancer and defines a group of patients with HER-2-positive breast cancer with significantly worse outcome.