Majority of women with early-stage breast cancer may not need chemotherapy, according to a recently published landmark study. “The findings will have an immediate impact on clinical practice, sparing thousands of women the side effects of chemotherapy,” the American Society of Clinical Oncology (ASCO) said in a statement.
The study, published in the New England Journal of Medicine, was able to “identify women who could safely skip chemotherapy and take only a drug that blocks the hormone estrogen or stops the body from making it,” The New York Times reports. These drugs are an essential part of treatment as they lower the risk of the disease recurring and new tumors from arising.
The women who could skip chemo were identified using gene tests on tumor samples. They were found to be “estrogen-sensitive, test negative for HER2 and have early stage tumors below five centimeters that have not spread to lymph nodes,” CNN reported.
It is a description that fits around 50 percent of women diagnosed with breast cancer worldwide. “They also have a score between 11 and 25 on the Oncotype DX Breast Recurrence Score test,” CNN added.
The recurrence test mentioned measures the likelihood of cancer recurring in the patient within 10 years. Those who score between 0 to 10 are advised to skip chemotherapy but take hormone therapy after their tumor is removed. Those who score between 26 to 100 are advised to have both chemotherapy and hormone therapy, Reuters explains.
Majority of patients, however, have scores between 11 to 25 (considered “intermediate”), and the problem lies in whether or not these women need chemotherapy.
“This has been one of the large unanswered questions in breast cancer management in recent times, what to do with patients with intermediate scores,” Dr. Larry Norton, who is not a part of the study, told The New York Times.
As per results from the landmark study, which spanned several years and involved over 10,000 women (who had the type of breast cancer mentioned—hormone receptor-positive, HER2-negative, and axillary node-negative), doctors may now have the answer they need.
More than 6,000 participants of the study had recurrence scores of 11 to 25. These women were randomly assigned to receive hormone therapy alone or both hormone therapy and chemotherapy. Results from the data comparing the two groups showed there was no benefit from adding chemotherapy to hormone therapy to the chosen participants. “There was no benefit in terms of overall survival, disease-free survival, or cancer spread beyond the breast,” reported HealthDay.
“Half of all breast cancers are hormone receptor-positive, HER2-negative, and axillary node-negative,” said lead study author Dr. Joseph A. Sparano, in a statement. “Our study shows that chemotherapy may be avoided in about 70 percent of these women when its use is guided by the test, thus limiting chemotherapy to the 30 percent who we can predict will benefit from it.”
Researchers add that women below 50 years old with a recurrence score of 16 to 25 may still benefit from chemo. But in all women above 50 who are in the early stages of the type of breast cancer described, chemo was not necessary, concluded the authors.
“Chemotherapy can save lives, but has serious risks that make it important to avoid treatment if it is not needed,” The New York Times explained. In the short-term patients suffer through nausea, fatigue, hair loss, an increased risk for infection, and, for younger women, infertility and early menopause, according to ASCO. “Certain delayed side effects that may occur months or years after chemotherapy are rare, but potentially serious, including heart failure and leukemia.”
The Philippines has one of the highest incidence rates of breast cancer in Asia with one in every 13 Filipinas expected to develop it in her lifetime, the Philippine Daily Inquirer reported. Breast cancer risk increases with age especially after 50, according to the Philippine Society of Medical Oncology.
This story originally appeared on Smartparenting.com.ph.
* Minor edits have been made by the Femalenetwork.com editors.