Study: More Breast Cancer Patients Can Safely Skip Chemotherapy

A federally funded study has found that many women with the most common type of early stage breast cancer likely do not need chemotherapy after surgery. The study was presented June 3, 2018 at the American Society of Clinical Oncology meeting in Chicago, and simultaneously published in the New England Journal of Medicine. It is likely to change the way many newly diagnosed breast cancer patients are treated.

"With results of this groundbreaking study, we now can safely avoid chemotherapy in about 70% of patients who are diagnosed with the most common form of breast cancer," said Kathy Albain, MD, a co-author of the study. "For countless women and their doctors, the days of uncertainty are over."

The Trial Assigning IndividuaLized Options for Treatment (TAILORx) study involved more than 10,000 women with hormone receptor (HR)-positive, HER2-negative breast cancer that had not spread to lymph nodes. The women’s tumors were tested with Oncotype DX, the brand-name of a gene expression test that can help predict if some early stage (stage 1 or 2) breast cancers are likely to come back after initial treatment. The test looks at a set of 21 genes in cancer cells from tumor biopsy samples to get a “recurrence score” between 0 and 100. The higher the score, the greater the chance the cancer will come back. Previous studies have found that women with scores of 10 or lower did not need chemotherapy, while women with scores higher than 25 did benefit from chemotherapy. But for the large group of women with intermediate scores (11 to 25) and their doctors, the need for chemotherapy has been less clear.

Most women in the mid-range can avoid chemo

The new study looked at the 6,711 women from the trial who fell in the mid-range of 11 to 25. The goal of the study was to find out if these women could safely skip the chemotherapy.

Following surgery, the women were randomly assigned to receive chemotherapy followed by hormone therapy, or hormone therapy alone. The study was intended to measure invasive disease-free survival, the proportion of women who had not died, or had their cancer return, or developed a new cancer. Results were very similar between the 2 groups.

  • Five years after treatment, the rate of invasive disease-free survival was 93.1% for those who had chemo and 92.8% for those who did not.
  • Nine years after treatment, the rate of invasive disease-free survival was 84.3% for those who had chemo and 83.3% for those who did not.

Rates of overall survival were also very similar between the 2 groups.

  • Five years after treatment, the rate of overall survival was 98.1% for those who had chemo and 98.0% for those who did not.
  • Nine years after treatment, the rate of overall survival was 93.8% for those who had chemo and 93.9% for those who did not.

"Until now, we've been able to recommend treatment for women with these cancers at high and low risk of recurrence, but women at intermediate risk have been uncertain about the appropriate strategy to take," said Jeffrey Abrams, MD, a co-author of the study. "These findings, showing no benefit from receiving chemotherapy plus hormone therapy for most patients in this intermediate-risk group, will go a long way to support oncologists and patients in decisions about the best course of treatment."

Age as a factor

Chemotherapy did appear to have some benefit in women who were age 50 or younger with a recurrence score of 16 to 25. For this age group, there were 2% fewer cases of cancer returning for recurrence scores between 16 to 20, and 7% fewer cases for scores between 21 to 25.

The authors conclude that the new findings suggest chemotherapy may be avoided in about 70% of women with HR-positive, HER2-negative, node-negative breast cancer. They say this applies to women who are:

  • older than age 50 and with a recurrence score of 11–25
  • any age with a recurrence score of 0–10
  • age 50 years or younger with a recurrence score of 11–15

The findings suggest that chemotherapy may be considered for the remaining 30% of women with HR-positive, HER2-negative, node-negative breast cancer – those who are:

  • any age with a recurrence score of 26–100
  • age 50 years or younger with a recurrence score of 16–25

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master's-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Adjuvant Chemotherapy Guided by a 21-Gene Expression Assay in Breast Cancer. Published June 3, 2018 in the New England Journal of Medicine. First author Joseph A. Sparano, MD, Albert Einstein College of Medicine, New York.


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