WASHINGTON, July 23 (UPI) -- Researchers in two studies have found that giving extra radiation to the lymph nodes of breast cancer patients can help reduce recurrence of the disease, though they have not yet shown whether the tactic will increase survival over the long term.
Breast cancer can spread regionally in the body to lymph nodes under the arm and collarbone, and can be spread by the lymph system to other parts of the body.
"Additional radiation to the surrounding lymph nodes reduced the risk of subsequent recurrence of breast cancer both locally, such as under the arm, and at sites distant from the breast, such as the bone, liver and lung," said Dr. Tim Whelan, a professor of oncology at McMaster University's Michael G. DeGroote School of Medicine. "The treatment did not increase survival, but follow-up is still relatively early."
The study done by McMaster University researchers, which is published in the New England Journal of Medicine, looked at 1,800 women between 2000 and 2007 who'd been diagnosed with node-positive or high-risk node-negative breast cancer, who were split in two groups, with one group receiving additional radiation and the other not.
There was only a 1 percent difference between the two groups of women in terms of surviving to a 10-year follow-up, however 82 percent of women in the group that received additional radiation to their lymph nodes did not have a recurrence of breast cancer, as opposed to 77 percent of the other group.
Another study of 4,000 women diagnosed between 1996 and 2004, which is also published in the New England Journal of Medicine, found that 3 percent more women had not experienced a recurrence of breast cancer, a statistically significant number.
Even without improvements in survival rates, the tactic has been successful enough that researchers said it can be factored in to treatment with patients, for whom personalization is quickly becoming the best way to strike back against cancer, said Dr. Rahul Tendulkar, a cancer specialist at Cleveland Clinic, in a press release.
"There are many different varieties of breast cancer," Tendulkar said. "A number of different factors must be taken into consideration when coming up with a treatment plan for each individual."
