SAN FRANCISCOThe decision to treat metastatic breast cancer with combination or single-agent chemotherapy may depend on the patient's and the clinician's perception and definition of the goals of such therapy, according to speakers at the 3rd Annual Oncology Congress.
"All therapy for metastatic breast cancer is palliative, and median survival depends mostly on the tempo of the patient's disease, defined by its biology, rather than the therapy we give," said Hyman B. Muss, MD, of the Vermont Cancer Center at the University of Vermont. "Once you've exhausted hormonal therapy in hormone-receptor positive patients, the average survival is only about 2 years. So the goal of treatment is to control disease and symptoms and to maximize quality of life."
In a debate session at the congress, Dr. Muss presented the argument for single-agent therapy for most patients with metastatic breast cancer.
Although Dr. Muss argued that "kindler, gentler" single-agent sequential therapy is generally the more appropriate choice, he cited possible exceptions: combination therapy with biologics such as bevacizumab (Avastin), trastuzumab (Herceptin), lapatinib (Tykerb), and ixabepilone (Ixempra), and combination therapy for symptomatic patients or those with rapidly progressing disease.
Taking the pro side was Hope Rugo, MD, of the UCSF Comprehensive Cancer Center. She argued for the rational use of combinations in metastatic patients (see Table), citing improvements in disease-free survival and in some cases overall survival. "You can improve upon being asymptomatic," she said.
Part of the difference in opinion on the question "Is A+B superior to A followed by B?" boils down to the definitions of "superior" and quality of life. Dr. Rugo argued that improvement in progression-free survival is a quality-of-life endpoint and is generally superior with combination therapy.