Twenty years ago, no targeted treatments existed for breast cancers with high levels of a protein called HER2 (HER2-positive, or HER2+). The significance of HER2 in breast cancer had only been recognized in 1987, when excessive levels of the protein were identified in about 20% of breast cancers. Oncologists realized that high levels of HER2 mark a type of cancer with a poor prognosis, as compared to the predominant type of breast cancer: estrogen receptor-positive, HER2 negative (HER2-).
The possibility of targeting HER2 to treat cancer was fulfilled in 1998, when the U.S. Food and Drug Administration (FDA) approved Herceptin (generic name trastuzumab), for treatment of metastatic HER2+ breast cancer. Made by Genentech, Herceptin is a type of drug known as a humanized antibody, meaning that it mimics an immune system attack on tumor cells, specifically those with high levels of HER2. Now, 20 years later, it is easier to appreciate the significance of this drug, which literally changed the lives of many HER2+ breast cancer patients, and continues to do so today. Continue reading…
Non-metastatic breast cancers are most often treated with surgery, but if the tumors are fairly large, or involve nearby lymph nodes, neoadjuvant (pre-operative) treatments with chemotherapy (NAC) are done first. NAC often reduces the tumor size and kills cancer cells in lymph nodes, if present, prior to surgery, improving the outcome. The best possible result of neoadjuvant treatment is pCR (pathologic compete response), when the tumor is no longer visible in imaging studies. Here, I review the new directions in which neoadjuvant treatments are evolving.
Today, treatments for metastatic breast cancers are tailored for specific subtypes. Starting with the introduction of the drug trastuzumab (Herceptin) for HER2-positive cancers, new, more specific treatment options were eventually developed and approved for other types as well. Estrogen deprivation endocrine therapies, lately prescribed in combination with CDK4/6 inhibitors, are used in estrogen receptor (ER)-positive cancers. Triple negative cancers (TNBC) are still treated mostly with chemotherapy, but immune checkpoint drugs and PARP inhibitors are explored in clinical trials, with some successes reported.
However, neoadjuvant treatments (except for HER2+ cancers) remain largely limited to chemotherapy regimens. This is starting to change now, with new approaches tailored to the cancer type being investigated in clinical trials.
In this regard, it is important to mention the I-SPY2 trial, NCT01042379, which started in 2010 and is for women with stage II-III breast cancer. It offers about a dozen drugs that are chosen based on particular features of the newly diagnosed cancers. This trial has a unique design and has produced some important results. Additional treatments and trials for various types of breast cancer are discussed below. Continue reading…
“The triplet combination of HER2-targeted therapy and an aromatase inhibitor (AI) improved progression-free survival (PFS) by more than 5 months compared with the combination of trastuzumab (Herceptin) and an AI in patients with HER2+/HR+ breast cancer.
“In phase III results from the ALTERNATIVE trial presented at the 2017 ASCO Annual Meeting, the median PFS was 11 months (95% CI, 8.3-13.8) for postmenopausal women with HER2+/HR+ metastatic breast cancer assigned to lapatinib (Tykerb) plus trastuzumab plus an AI compared with 5.7 months (95% CI, 5.5-8.4) for patients assigned to trastuzumab plus an AI. Lead study author William J. Gradishar MD, interim chief of hematology and oncology at Northwestern University’s Feinberg School of Medicine, said that represented a 38% reduction in the risk of progression (HR, 0.62; 95% CI, 0.45-0.88; P = .0064).”
“Dual blockade of HER2 with lapatinib plus trastuzumab and an aromatase inhibitor (AI) was superior to single blockade with trastuzumab plus an AI in postmenopausal women with HER2-positive, hormone receptor (HR)-positive metastatic breast cancer, according to the results of the phase III ALTERNATIVE study (abstract 1004) presented at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting, held June 2–6 in Chicago.
” ‘Dual HER2 blockade with this triplet of lapatinib/trastuzumab and an AI can offer an effective and well-tolerated chemotherapy-sparing option for patients who are not intended or appropriate for chemotherapy,’ said researcher William J. Gradishar, MD, of the Robert H. Lurie Comprehensive Cancer Center at Northwestern University in Chicago, who presented the results.”
“Results from the KRISTINEand NSABP B-41 trials provided the latest data on the use of pertuzumab (Perjeta), trastuzumab (Herceptin), ado-trastuzumab emtansine (T-DM1; Kadcyla), and lapatinib (Tykerb) for the neoadjuvant treatment of patients with HER2-positive breast cancer.
“In a lecture at the 2016 ASCO Annual Meeting, Stephen K. Chia, MD, an assistant professor in the division of Medical Oncology at the University of British Columbia, highlighted the key findings from these trials and their implications for the treatment of HER2+ breast cancer.”
“Results from the KRISTINEand NSABP B-41 trials presented at the 2016 ASCO Annual Meeting provided the latest data on the use of pertuzumab (Perjeta), trastuzumab (Herceptin), ado-trastuzumab emtansine (T-DM1; Kadcyla), and lapatinib (Tykerb) for the neoadjuvant treatment of patients with HER2-positive breast cancer.
“In a lecture at the conference, Stephen K. Chia, MD, an assistant professor in the division of Medical Oncology at the University of British Columbia, highlighted the key findings from these trials and their implications for the treatment of HER2+ breast cancer.”
“Amsterdam, The Netherlands: Approximately a quarter of women with HER2 positive breast cancer, who were treated with a combination of the targeted drugs lapatinib and trastuzumab before surgery and chemotherapy, saw their tumours shrink significantly or even disappear, according to results from a clinical trial.
“Professor Nigel Bundred told the 10th European Breast Cancer Conference (EBCC-10) today (Thursday): ‘This has ground-breaking potential because it allows us to identify a group of patients who, within 11 days, have had their tumours disappear with anti-HER2 therapy alone and who potentially may not require subsequent chemotherapy. This offers the opportunity to tailor treatment for each individual woman.’
“Prof Bundred, who is Professor of Surgical Oncology at The University of Manchester and the University Hospital of South Manchester NHS Foundation Trust (UK), was presenting results from the UK EPHOS-B multi-centre, clinical trial, in which 257 women with newly-diagnosed, operable, HER2 positive disease were recruited between November 2010 and September 2015.”
“Among patients with HER2-positive, metastatic breast cancer that had progressed despite treatment with two or more forms of HER2-targeted therapy (trastuzumab [Herceptin] and lapatinib [Tykerb]), median overall survival was increased for those treated with trastuzumab emtansine (T-DM1 [Kadcyla]) compared with those who received treatment of physician’s choice, according to results from the phase III TH3RESA clinical trial presented at the 2015 San Antonio Breast Cancer Symposium, held Dec. 8–12.
“The HER2-targeted antibody-drug conjugate T-DM1 was approved by the U.S. Food and Drug Administration in February 2013 for treating patients with HER2-positive, metastatic breast cancer that had progressed after treatment with trastuzumab and a taxane.”
“The primary analysis of the phase III CALGB 40601 trial found that pathologic complete response (pCR) to dual HER2 blockade was not statistically higher than anti-HER2 monotherapy. However, there was a high level of intertumoral heterogeneity, and patients with the HER2-enriched subtype had a high pCR with both single and dual anti-HER2 therapy, according to data recently published in the Journal of Clinical Oncology.
“ ‘This trial paves the way for integrating molecular analyses into other trials in HER2-positive breast cancer, and may allow us to take a less-is-more approach for women who are selected to be highly sensitive to targeted treatments and to have a good prognosis,’ said lead study author Lisa Carey, MD, a UNC Lineberger member, the Richardson and Marilyn Jacobs Preyer Distinguished Professor in Breast Cancer Research at the University of North Carolina School of Medicine, and the physician-in-chief of the North Carolina Cancer Hospital, in a statement.”