By Kathleen Doheny
WEDNESDAY, Nov. 9, 2016 (HealthDay News) -- A more intense type of chemotherapy offers little benefit over standard chemotherapy for women with high-risk early breast cancer, European researchers report.
Known as tailored dose-dense chemotherapy, the treatments are given over a shorter period of time without increasing the overall dose. It has been suggested as a way to improve the effectiveness of the treatment for early breast cancer.
However, the European study did not find a difference in recurrence-free survival or overall survival after five years of follow-up. The investigators did find that the dose-dense group had better event-free survival, defined as the time to any breast cancer relapse, cancer in the opposite breast, other malignant growths or death from any cause.
Despite the results, a U.S. breast cancer expert said there is still a role for the approach in certain women.
Researchers from The Swedish Breast Cancer Group, led by Dr. Jonas Bergh of the Karolinska Institute and University Hospital in Stockholm, randomly assigned more than 2,000 women to either the standard chemotherapy group or the dose-dense group. All of the participants had had surgery for node-positive or high-risk node-negative breast cancer.
After five years, 89 percent of the dose-dense group and 85 percent of the standard group were alive and had no recurrence of cancer. In addition, the researchers found that 87 percent of the dose-dense group had event-free survival at five years, compared with 82 percent of the standard group.
Some patients answered questions about quality of life and side effects. Those in the dose-dense group reported worse quality of life on parameters like sexual functioning and side effects such as fatigue, the findings showed.
Dr. Joanne Mortimer is director of women's cancer programs and co-director of the breast cancer program at the City of Hope Cancer Center in Duarte, Calif.
"I don't know that everyone needs dose-dense [chemotherapy] but I think it may be better in triple-negative breast cancer," she said.
In so-called triple-negative breast cancers, the usual receptors known to fuel breast cancer are not found. These cancers are estrogen receptor-, progesterone receptor- and HER2-negative. These cancers can be aggressive and more likely to recur.
Mortimer cited another study, published in 2010, in which researchers reviewed more than 3,000 breast cancer patients and compared the two approaches. Their conclusion was that the dose-dense approach resulted in better overall and disease-free survival, especially in women with hormone receptor-negative cancers.
The other potential benefit of dose-dense, Mortimer said, is that the chemotherapy is administered over a shorter period of time, which most women welcome. "I think most patients are happy to be done sooner," she added.
Dose-dense is typically given every two weeks, and the treatment is finished in eight weeks. In standard therapy, it is typically given every three weeks, for a total of 12 weeks, the researchers said.
The more intense treatment can cause issues with low blood cell counts, however. So, "when you give it, you do have to give it with white blood cell growth factors" to offset that problem, Mortimer explained.
The new study was published Nov. 8 in the Journal of the American Medical Association.