The American Society of Clinical Oncology (ASCO) issued on 2 September 2014 a new clinical practice guideline on chemotherapy and targeted therapy for women with HER2-negative (or HER2 status unknown) advanced breast cancer. The guideline provides detailed, evidenced-based information on the efficacy and side effects of various therapies.
To develop this clinical practice guideline, an ASCO Expert Panel conducted a formal systematic review of relevant medical literature published from 1993 through May 2013. The review considered 20 systematic reviews and/or meta-analyses and 30 clinical trials on first-line treatment, and 29 trials on second-line and subsequent treatment for women with advanced HER2-negative breast cancer.
Outcomes of interest included survival, progression-free survival, response, quality of life, and adverse effects. Guideline recommendations were evidence-based and agreed upon by the Expert Panel via consensus.
Nearly 80% of women with advanced breast cancer are HER2-negative, meaning that they have normal levels of HER2 protein in their tumour and are not candidates for HER2 targeted therapies. The new ASCO guideline assesses systemic therapy options for these women.
The guideline states and recommends:
- Hormone therapy should be offered as the standard first-line therapy for women with hormone receptor positive advanced breast cancer, unless improvement is medically necessary as for example in case of immediately life-threatening disease, or if there is concern about resistance to hormone therapy.
- Different chemotherapy agents should be given sequentially, rather than in combination, to reduce side effects and preserve quality of life.
- Doctors and patients should make treatment choices together, taking into consideration prior therapies, side effects, schedule, co-morbidities, and patient preference because there is no single optimal chemotherapy.
- Bevacizumab should only be considered with single-agent chemotherapy when there is immediately life-threatening disease or severe symptoms. However, it should be noted that bevacizumab, which has been shown to shrink tumours and delay disease progression in some patients, but does not extend overall survival, is not approved by the Food and Drug Administration for the treatment of breast cancer in the United States.
- No other targeted agents should be used in addition to, or as a replacement for, chemotherapy. One targeted drug, everolimus, is approved for use with hormonal therapy exemestane for women with hormone receptor positive breast cancer but earlier in the course of the disease, when the cancer may still be responsive to hormonal therapy.
- Palliative care should be initiated early and offered throughout the continuum of care.
- As no cure is yet available for advanced breast cancer, doctors should encourage all eligible patients to participate in clinical trials and potentially benefit from promising experimental treatments.
The guideline was published in the Journal of Clinical Oncology.
Partridge AH, Rumble RB, Carey LA, et al. Chemo- and Targeted Therapy for Women with HER2 Negative (or unknown) Advanced Breast Cancer: American Society of Clinical Oncology Clinical Practice Guideline. JCO 2014; Published online before print September 2. doi: 10.1200/JCO.2014.56.7479