Many breast cancer patients can skip chemo, study says
Finding could spare 70,000 in US from harsh treatment regimen
Thousands of women could skip painful and detrimental chemotherapy in treating early-stage breast cancer, according to a groundbreaking study.
The decade-long study, discussed Sunday at the American Society of Clinical Oncology conference in Chicago, was hailed as the largest breast cancer treatment trial ever conducted. It showed that most patients with an intermediate risk of cancer recurrence can avoid chemotherapy without hurting their chances of beating the disease.
That could affect up to 70,000 women a year in the United States and thousands more around the world, the study said.
“The impact is tremendous,” said the study’s leader, Dr. Joseph Sparano of Montefiore Medical Center in New York. Most women in this situation don’t need treatment beyond surgery and hormone therapy.
The study, funded by the National Cancer Institute, foundations and proceeds from the U.S. breast cancer postage stamp, is the latest development in a national trend on cancer treatments. For several years, cancer care has been evolving away from chemotherapy — older drugs with harsh side effects — in favor of gene-targeting therapies, hormone blockers and immune system treatments. When chemo is used now, it’s sometimes for shorter periods or lower doses than it
once was.
The study cast doubt on chemo’s necessity in treating women in early stages of the disease where it has not spread to lymph nodes, it is hormonepositive and it is not the type that the drug Herceptin targets.
The breast cancer study gave 10,273 patients a test called Oncotype DX, which uses a biopsy sample to measure the activity of genes involved in cell growth and response to hormone therapy, to estimate the risk that a cancer will recur.
For the study, the 67 percent of women showing an intermediate risk of recurrence had surgery and hormone therapy and half of those also received chemo. After nine years, 94 percent of both groups were still alive and about 84 percent were alive without signs of cancer, meaning that the chemo made no difference.
Dr. Lisa Carey, a breast specialist at the University of North Carolina’s Lineberger Comprehensive Cancer Center, said she would be very comfortable advising patients to skip chemo if they were like those in the study who did not benefit from it.
“Oncologists have been getting much smarter about dialing back treatment so that it doesn’t do more harm than good,” Steven Katz, a University of Michigan researcher who examines medical decision-making, told The Washington Post. “That’s important because chemo is toxic; it whacks patients out and can result in longterm job loss.”
Dr. Jennifer Litton, at MD Anderson Cancer Center in Houston, agreed, but said patients should be cautious. “Risk to one person is not the same thing as risk to another.”