mammogram image; Photo by thomasandreas, Getty Images/iStockphoto
Chemotherapy does little to boost long-term survival rates for many women with the most common form of breast cancer. Most only need hormonal treatment following surgery, according to a study released June 3.
That means thousands of women can be safely spared the toxic effects of chemotherapy, says William J. Irvin Jr. the Virginia medical director for medical oncology, and director of clinical research for Bon Secours Virginia Health System and Bon Secours Cancer Institute. “This is clearly a win,” he says.
The study looked at data from the Trial Assigning Individualized Options for Treatment (TAILORx), a long-term (it followed women for nine years), extensive trial (more than 10,000 participants at 1,182 sites). The breast cancer type involved is described as hormone receptor positive, HER2-negative, and has not spread into the lymph nodes, according to a National Cancer Institute release.
Study results will provide women more accurate information when weighing treatment options, and help ensure that women receive the optimal level of care instead of over-treatment.
“It’s been a 15-year process to develop more precise tests that basically let’s us identify who these women who would benefit, and the others who do not and can be spared chemo,” says Charles E. Geyer Jr., associate director of clinical research at VCU Massey Cancer Center, and a study author.
In TAILORx, tumors taken from participants were subject to a gene expression test. Test results were used to determine a risk score for cancer recurrence on a scale of 0 to 100. Women determined to be at a low risk had a score of 0 to 10, and received only hormone treatment. Women in the mid-range had a score of 11 to 25 and were randomly assigned to either receive both hormone treatment and chemotherapy or just hormone therapy alone. A score of 26 and above was considered high risk, and those women received both chemotherapy and hormonal treatment.
Researchers found that women in the mid-range who received only hormone therapy after tumor removal had the same 9-in-10 survival rate of their cancer without a recurrence of the disease when followed up after five years as the women who had received both chemotherapy and hormonal therapy. They also basically had the same survival rate without recurrence after nine years (83.3 percent for hormone therapy and 84.3 percent for combined therapies), according to the National Cancer Institute report. Including the women who had a recurrence of the disease, the overall survival rate after nine years was just under 94 percent for both groups. The recurrence rate was 3 percent after nine years for the women in the low-risk group who had received only hormone therapy.
The study suggest that hormone-only treatment should be recommended for anyone with a 0 to 10 recurrence score, and also for anyone 50 or younger with a score of 11 to 15, and for women older than 50 with a score of 11 to 25.
Chemotherapy may be considered proper for a woman with a higher-end score of 26 or more, and for a women age 50 or younger with a score of 16 to 25.
A large percentage of women with this type of cancer fell into the middle-range, and that’s where the precision was needed, and the trial delivered, says Geyer. “TAILORx was a real ambitious effort,” he says.
Irvin notes that technology has improved and practices have been refined since the TAILORx began a decade ago, and that most up-to-date oncologists had already been recommending the treatment regimen. “What this does is really affirm that practice,” he says.
