A recently published U.S.-led study of more than 10,000 women whose tumours were tested determined that most patients with early-stage estrogen-positive breast cancer and no lymph-node spread should be able to avoid chemo and be treated with surgery, radiation and a hormone-blocking drug like tamoxifen alone.
The study is the largest ever performed looking at breast cancer treatment, and its results are expected to spare thousands of women in Canada each year from having to undergo rounds of chemotherapy and its harsh side-effects.
Funded by the U.S. National Cancer Institute, with additional funding from the Canadian Cancer Society Research Institute, the research looked at women with breast cancer with an intermediate risk of recurrence, based on their scores from the genetic test.
Previously, scores from the US$3,000 Oncotype DX test, used since 2004, allowed doctors to sort out women at high risk and low risk of recurrence to determine whether they would benefit from chemotherapy.
But women with in-between scores fell into a grey area — should they get chemo or not?
That’s what the study, which began in 2006 and included 10,253 women aged 18 to 75, set out to determine, with participants randomized to receive chemo plus a hormone-dampening drug or that medication alone.
The results were stunning.