The largest ever breast cancer treatment trial has found 70 percent of early-stage breast cancer patients receive no benefit from chemotherapy and can be effectively treated with endocrine therapy alone.
The trial, Trial Assigning IndividuaLized Options for Treatment (Rx), or TAILORx, was sponsored by the US National Cancer Institute (NCI). It involved over 10,000 participants enrolled since 2006 at sites in five countries, including Australia and New Zealand.
According to Genomic Health, the world's leading provider of genomic-based diagnostic cancer tests, including the Oncotype DX Breast Recurrence Score test, around 50 percent of all breast cancer patients diagnosed worldwide each year have hormone-receptor positive, HER2-negative, node-negative cancer.
The tumours of trial participants were analysed using the Oncotype DX Breast Recurrence Score test. It examines the activity of 21 genes to predict the risk of a recurrence over 10 years
"The TAILORx study definitively established that chemotherapy may be spared in about 70 percent of these patients, including all women older than 50 with Breast Recurrence Score results of 0 to 25 and all women age 50 or younger with Breast Recurrence Score results of 0 to 15," said the company.
"Importantly, 30 percent of early-stage breast cancer patients will derive benefit from chemotherapy, including women of any age with Breast Recurrence Score results of 26 to 100, and in women younger than 50, where a modest (2 percent) benefit from chemotherapy was observed with Breast Recurrence Score results of 16 to 20, which gradually grew as scores increased up to and above 25."