More Breast Cancer Patients Can Skip Chemo - Gene Test

For some breast cancer patients, the chemo decision may now be easier

The confusion comes from a genetic test called Oncotype DX that rates the likelihood of breast cancer recurrence on a 100-point scale.

All of the women in the study, called the Trial Assigning Individualized Options for Treatment (Rx), or TAILORx, had their breast tumors analyzed with a molecular test. Some women 50 or younger, however, did see benefits from chemo. He is not an author of the study, but his hospital participated.

The first patient to undergo the treatment, Judy Perkins, was diagnosed with incurable stage 4 breast cancer in 2013, ten years after undergoing a mastectomy for an earlier bout with the disease.

While chemo can be greatly helpful to some patients, it has a significant number of drawbacks and serious side effects. "It was all gone", she said.

However, the results of the TAILORx trial show only 30 per cent of women with this particular form of early-stage breast cancer benefit from the treatment.

But most women get an intermediate result meaning they are unclear as to what to do. That means more than 85,000 women a year can safely forgo chemotherapy. Twenty-five percent of those patients won't qualify for chemotherapy because of age or medical problems.

New research suggests that more breast cancer sufferers may be able to avoid grueling chemotherapy treatment.

The global trial, known as TAILORx, involved over 10,000 women from 1,182 research units in Ireland, the US, Canada, Australia, New Zealand and Peru.

Breast cancer is the second most common cancer among women in the United States, behind only skin cancer. Researchers used it to estimate the risk that a cancer will come back based on 21 genes linked with breast cancer recurrence.

All the same, he says, the message of the new study isn't that chemotherapy is irrelevant. "Chemotherapy has saved a tremendous amount of lives, and will continue to do so", Dr. José Baselga said, via NPR.

Rosenberg says investigators have already tested the approach in liver and colorectal cancer, but the "big picture" is that it is not cancer type-specific. Endocrine therapy, such as tamoxifen, is more important with this disease than chemotherapy, said Otis Brawley, chief medical and scientific officer for the American Cancer Society.

The new research now indicates that these women in this range would most likely not benefit from the costly and often physically devastating chemotherapy protocol. Now only about 60 percent of USA patients who could potentially benefit from it are taking the gene test, he says. Chemotherapy could still be on the table for people who fall outside of this group.

Albain said research is ongoing, as scientists are now exploring questions about what types of chemotherapy might be effective on various groups based on their genomics, and what will happen to the participants of the clinical trial as even more time passes. The researchers gave half the women hormone-blocking drugs alone, and half hormone-blocking drugs and chemotherapy.

"I was very sceptical about whether this treatment would work because I knew the odds were not really great", said Perkins. Others want chemo for even the smallest chance of benefit.

The treatment is not only expensive but physically demanding and several other patients in the clinical trial died during treatment, including several who succumbed to side effects. "After the treatment dissolved most of my tumours, I was able to go for a 40-mile hike", she added.

Sara Kiley Watson is NPR's Science Desk intern.