New Treatment Guidelines for Advanced Breast Cancer
Panel addresses HER2-negative disease
A leading group of oncologists has released updated guidelines for the treatment of the major form of advanced breast cancer.
Human epidermal growth factor receptor 2 (HER2)-negative breast tumors include cancers that don’t respond to drugs that target the HER2 protein, the American Society of Clinical Oncology (ASCO) explained in a recent announcement. Almost 80% of women with advanced breast cancer have HER2-negative tumors, the group noted.
“In releasing this guideline, our aim is to improve both the length and quality of patients’ lives,” Dr. Ann Partridge, co-chair of the expert panel that developed the guidelines, said in the statement. “Although no clear chemotherapy winner emerged, the guideline will help doctors and patients choose the best therapy based on what treatment would be most tolerable and convenient for the patient.”
The new guidelines — published September 2 in the Journal of Clinical Oncology — are geared toward women with advanced cancers who are set to begin a chemotherapy regimen.
The ASCO panel believes that hormonal therapy should be the first choice of treatment for women whose tumors carry receptors for estrogen. There were exceptions to that advisory: women who had “immediately life-threatening” disease or who might prove resistant to hormone therapy might be referred to another treatment, ASCO said.
To identify optimal chemotherapy and targeted therapy for women with HER2–negative (or unknown) advanced breast cancer, the authors reviewed randomized evidence (including systematic reviews and meta-analyses) from 1993 to the present. Outcomes of interest included survival, progression-free survival, response, quality of life, and adverse effects.
Seventy-nine studies met the inclusion criteria: 20 systematic reviews and/or meta-analyses, 30 trials of first-line treatment, and 29 trials of second-line and subsequent treatment. These studies formed the evidence base for the guideline recommendations.
Bevacizumab (Avastin, Genentech), a recombinant humanized monoclonal immunoglobulin G1 antibody, is not advised for most patients and “should only be considered with single-agent chemotherapy when there is immediately life-threatening disease or severe symptoms,” the panel said. Bevacizumab is not approved for the treatment of breast cancer.
When it comes to the timing of various chemotherapies, the ASCO experts said women should be given treatments in sequence, not in combination. That approach should help curtail side effects and help boost the patient's quality of life.
For patients with advanced breast cancers, the ASCO panel advised against the use of certain “targeted” drugs in addition to, or in place of, recommended chemotherapies. One such targeted medication, everolimus (Afinitor, Novartis), has been approved for use in combination with the hormonal drug exemestane (Aromasin, Pfizer) — but only for patients with early-stage breast cancer.
All decisions as to which therapy to take and when should be based on detailed discussions between a patient and her physician, the ASCO panel suggested. Factors to consider are a woman’s history of prior treatments, potential side effects, the scheduling of treatments, other medical conditions the patient might have, and the patient’s personal preference “because there is no single optimal chemotherapy,” the panel said.
“There are many different types of treatments available but some are unnecessarily toxic,” Dr. Ian Smith, co-chair of the expert panel that developed the guidelines, explained in the statement. “This guideline emphasizes that breast cancer can often be controlled with less-intensive approaches that offer a better quality of life for patients. Patients should be involved in decisions about their own treatment and also encouraged to participate in clinical trials whenever possible.”