Researchers have come up with a genomic test that assesses the activity in 70 genes responsible for growing and spreading cancer in the body, helping identify women with early-stage breast cancer who can skip out on chemotherapy.

In a study published in The New England Journal of Medicine, researchers identified early-stage breast cancer patients who survived for five years without metastasis using a genomic test called MammaPrint.

This is not the first time a genomic test has been used for a cancer-related purpose, but there is a growing recognition in how it is able to effectively identify breast cancer patients who can do away with chemo safely. However, the study is one of the most rigorous and largest, which is helpful in reassuring doctors and patients alike that the technology can be trusted.

MammaPrint works by assessing the activity of 70 genes. Those with high-risk tumors will have 50 of the genes turned on and the rest turned off. In low-risk cases, it's the opposite: 50 genes turned off and 20 active.

"[U]sing MammaPrint could change clinical practice by substantially de-escalating the use of adjuvant chemotherapy and sparing many patients an aggressive treatment they will not benefit from." said Martine Piccart, M.D., Ph.D., one of the study's authors and Medicine Department head of the Jules Bordet Institute in Brussels.

According to the study, almost half of women diagnosed with early-stage breast cancer who would normally be on the receiving end of chemotherapy can actually avoid the treatment with little risk of their cancer spreading or coming back.

In another study published in the journal Oncotarget, researchers also turned to genes to assess death risk in patients with breast cancer. According to their findings, they discovered that women with cancer cells that are low in the STC2 gene, but high in the F12 gene are 32 percent likelier to succumb to the disease within the next 10 years. However, if cancer cells were high in STC2 but low in F12, breast cancer patients only had a 10-percent chance of dying within the same period of time.

Obesity has been found to be linked to higher risks of developing breast cancer and these risks increase the longer a woman is overweight. Specifically, for every decade that a woman is overweight, their chances of developing a cancer type associated with obesity increases by up to 7 percent. In the case of breast cancer, the risks of developing the disease can go up by as much as 5 percent in women who are overweight.

Excess weight plays a role in increasing cancer risk because it promotes inflammation, which is ideal for tumor growth.

Photo: Ed Uthman | Flickr