"We can spare thousands and thousands of women from getting toxic treatment that really wouldn't benefit them", Dr. Ingrid A. Mayer, from Vanderbilt University Medical Center and author of the study, was quoted as saying.
Results from this study suggest many women with this specific type of tumour do not receive any additional benefit from having chemotherapy in combination with endocrine therapy, compared to endocrine therapy alone.
Experts believe the case, discussed at the American Society of Clinical Oncology meeting in Chicago, marks the start of a breakthrough for thousands of women who now have no hope. We think this area needs more voices, reasoned analysis and ideas than just those provided by News Corp, lifestyle mags, Facebook groups and corporate newsletters.
"It feels miraculous, and I am beyond amazed that I have now been free of cancer for two years", Ms Perkins said.
She said the breast cancer study and others like it show the importance of research groups like the CRCWM and how their work can have huge payoffs. But of the 7,000 women overall in the 11-25 range, 70% wouldn't have actually needed chemotherapy, Kathy Albain, an oncologist at Loyola University Medical Center in IL, told NPR.
According to Dr. Stephanie Bernik, chief of surgical oncology at Lenox Hill Hospital in New York City, "Breast surgeons and oncologists have been using the 21-gene assay for years to guide treatment after surgical excision". Oncotype DX and other genomic tests have spurred a trend sure to accelerate following Sunday's report.
Usually, after the removal of the tumor, many women undergo chemotherapy combined with hormonal treatment to prevent any return of the cancer.
Of those, 6,711 scored in the intermediate range of 11-25, and were randomly assigned hormone therapy alone or hormone therapy plus chemotherapy. "The trial was created to address this question, and provides a very definitive answer".
The researchers performed a prospective trial between 2006 and 2010 involving 10,273 women with hormone-receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative, axillary node-negative breast cancer.
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She was married to Andy Spade , the brother of actor David Spade , and had a 13-year-old daughter, Frances. Kate Spade Handbags was launched in 1993, with its first store located in Manhattan's SoHo neighbourhood.
Oncotype DX is becoming more standard. The results are sure to accelerate the decline in chemotherapy for the disease. They were then monitored for an average of 7.5 years to see how many of them died or had their cancer recur.
While previous studies demonstrated that patients with low scores (10 or lower) did not need chemotherapy, and women with high scores (above 25) did require and benefit from chemotherapy, there was no conclusive research guiding patients and doctors on whether or not to undergo chemotherapy in cases with a tumor with a midrange score, according to the study.
It follows trials of a genetic test that analyses the danger of a tumour.
Forty-nine-year-old Judy Perkins was faced with a terrifying prognosis after several rounds of punishing chemotherapy had failed to stop a tumour in her right breast.
Charity Breast Cancer Care said it was a "life-changing breakthrough".
This means thousands of women will be able to avoid all of the side effects chemotherapy implies, such as nausea, vomiting, hair loss and fatigue, while still achieving positive long-term outcomes. But as doctors began to learn more about the disease, experts decided many patients were being over-treated.
"I, as an oncologist on Monday in clinic, will offer less chemotherapy that will not be of benefit to patients and that is very reassuring to know that when I am offering patients chemotherapy they are likely to benefit from it".
Doctors at the U.S. National Cancer Institute concluded that Perkins wouldn't survive with conventional therapy and as a result picked her for a radical new therapy which harnessed the power of her immune system to fight the tumours.