An experimental new therapy for advanced breast cancer is being hailed as a "paradigm shift" in treating the disease.
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.
"It feels miraculous, and I am beyond amazed that I have now been free of cancer for two years", Ms Perkins said.
When she was selected for the trial in 2015, the Florida woman "had tennis ball-sized tumours in her liver and secondary cancers throughout her body". Following this "recalibration" of the genetic test, the researchers estimated that chemotherapy was not justified in 70% of cases of breast cancer.
A 21-gene test called Oncotype Dx that has been around since 2004 has helped guide some decisions, post-surgery. "With all the side effects that chemotherapy has, if there's any way it can be avoided, if it's not necessary, you don't want to give it, you don't want to take it", Yost said.
The TAILORx study, led by the Montefiore Medical Centre in NY, found women older than 50 with this form of breast cancer and a score of up to 25 did not need chemotherapy. Should we not give them chemotherapy?
"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". For the past 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. But the researchers who conducted this new controlled experiment found that chemotherapy provided no additional benefit over hormone treatments alone. Dr Steven Rosenberg, chief of surgery at the National Cancer Institute said that this was the most "personalized" form of medicine that there is.
The phase III clinical trial, named "TAILORx", followed over 10,000 women diagnosed with breast cancer between 2006 and 2010. Patients using both types of treatment had an overall survival rate of 93.8 percent.
The technique has previously been used to treat blood cancers and melanoma, but "it is the first time the treatment has been successful for late-stage breast cancer".
Now we do. This very large, very important study is telling us that people with those intermediate scores have a very good prognosis and that prognosis is not improved by chemotherapy.
Until now, chemotherapy was highly recommended with a result greater than 25, and below 10 it was not.
"We have been waiting for these results for years", said Allison Kurian, an oncologist at Stanford University who wasn't involved in the trial.
There was some benefit from the chemotherapy for a small subgroup - women with a score of 16 to 25 who were age 50 or younger, Sparano's team said.
"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 MI researcher who examines medical decision-making, told the Washington Post.