New test may spare chemo
likemanywomen,CharlotteDew dreaded the prospect of chemotherapy after having surgery to remove a cancerous lump in her breast, especially since her doctors were uncertain if these powerful drugs were actually needed to prevent the disease from spreading.
Dew’s cancer, diagnosed last summer, was found to be small and slowgrowing, although a biopsy showed that some cells had spread to one of the nearby lymph nodes, under the arm, indicating a risk that the cancer could come back.
“The doctors couldn’t tell me if I would benefit from chemotherapy or not,” the 49-year-old gynaecologist recalls. “It was hard to make a decision. Chemotherapy is horrible, and I wanted to avoid the side-effects such as nausea and hair loss if I could, but at the same time I was worried — supposing I didn’t have chemotherapy and the cancer recurred?”
It was then that Dew learned from her surgeon about a new gene test that is being hailed by specialists in the U.K. as a breakthrough in breast cancer diagnosis. Developed by a California-based company and called Oncotype DX, it can help women and their doctors decide if they need chemotherapy after breast cancer surgery. Already used extensively in the U.S., it is now available privately in the U.K., at a cost of about $4,000.
Known as a genomic assay, OncotypeDXinvolvesextractingRNAfrom a sample of the breast tumour and analyzing the activity of 21 genes controlling the behaviour of cancer cells. It gives a recurrence score, which indicates how likely the cancer is to return within 10 years of the initial diagnosis, with the risk being graded as low, intermediate or high. It also calculates how likely an individual woman is to benefit from chemotherapy.
According to Simon Cawthorn, a breast surgeon at the Breast Care Centre at Southmead Hospital, Bristol, the test is an “exciting breakthrough” that could benefit about half of all women with breast cancer. It is suitable for women with early-stage cancer that is fuelled by estrogen.