The study, led by the Albert Einstein Cancer Center in NY, is a rare cancer breakthrough as it can save money and instantly change practice. Some study leaders consult for breast cancer drugmakers or for the company that makes the gene test. "I spoke to four people about her case, including one of the doctors associated with the Tailorx trial", said Dr Ramesh Sarin, senior consultant surgical oncology at the Indraprastha Apollo Hospitals.
The results are expected to spare as many as 70,000 women from the expensive procedure that comes with harsh side effects.
Previously, the same study had shown that women with a low risk of recurrence can avoid chemo, and other studies had shown that those with a high risk of recurrence should receive it. Today, she said, she has a "few spots" in her left lung that Rosenberg believes may be scar tissue.
Rachel Rawson, of Breast Cancer Care, added: "This life-changing breakthrough is absolutely wonderful news and could liberate thousands of women from the agony of chemotherapy".
"Moving forward, when women are making this decision, this study will help us put it into perspective and give them better advice next week than we were able to give them last week", Jennifer Litton, an associate professor and oncologist at MD Anderson Cancer Center in Houston, Texas, explained to USA Today. Twenty-five percent of those patients won't qualify for chemotherapy because of age or medical problems.
"We went rafting down the Grand Canyon", said Perkins, who has two sons and two stepsons with her husband.
The findings only apply to women with specific early stage breast cancers.
Meanwhile, according to Prof Bryan Hennessy, clinical lead of Cancer Trials Ireland, this is a "globally important breast cancer trial". It's called the Oncotype DX test.
The treatment, which is known as T-cell immunotherapy, works a little something like this.
In an article commenting on the results of Dr Rosenberg's trial, Dr Laszlo Radvanyi of the Ontario Institute for Cancer Research said they provided evidence that "we are now at the cusp of a major revolution" in cancer immunotherapy.
According to a new United States study, after the tumor has been removed from the breast, chemotherapy would only be needed in 20% of cases for patients suffering of breast cancer.
"All cancers have mutations, and that's what we're attacking with this immunotherapy", he said. But as doctors began to learn more about the disease, experts decided many patients were being over-treated. It was first issued in 1998 and has been reissued multiple times since, and has raised more than $86 million for breast cancer research.
Gilead shares gained as much as 3.7 percent on Monday, and were up 1.9 percent to $69.60 at 11:16 a.m.in NY.
The dramatic success has raised hopes that the therapy will work in more patients with advanced breast cancer and other hard to treat cancers, such as ovarian and prostate. The tumour is assigned a "recurrence score" from 0 to 100 - higher the score, greater the chance the cancer will recur, with chemotherapy reducing the risk of recurrence.
In past studies. doctors looked back at the data for patients in this third group and determined that they would benefit from chemotherapy.
Harold Burstein, a breast cancer specialist at Dana-Farber Cancer Institute, said that in some ways the debate over de-escalation misses a larger issue.