CHICAGO (CBS) — A new study published Tuesday said that a device that sends electrical impulses to the brain can disrupt the growth of tumor cells in the kind of cancer Senator John McCain has.

The device has electrodes that are attached to the shaved head of a person who has glioblastoma, an aggressive form of brain cancer. The device is worn nearly 24/7, except for occasional breaks and weekly electrode changes.

Dr. Roger Stupp, the study’s lead author and professor at Northwestern University’s Feinberg School of Medicine said those who have worn the device were found to have lived, on average, five months longer than those who don’t.

“There are more patients who are alive at 2 years and 3 years and longer with this device,” he said.

The way the device works is it sends low-level electric signals to the glioblastoma.

“If you turn around the magnetic field in a certain frequency, you will perturb the dividing tumor cells in a way that they cannot appropriately divide and they will ultimately die,” Dr. Stupp said.

He said treatment with the device is typically two years and is repeated once the cancer cells start multiplying again.

Dr. Stupp says he’s been looking extensively for more than 20 years to find new treatments for glioblastoma and that, while the device is not a cure for the cancer, “every step forward makes me feel happy for my patients. We care for patients and we need better treatments and that’s the kind of engine for our research.”

He said it appears that Sen. McCain did not use the device or else people would have seen him with a shaved head, wearing it.

The study is in Tuesday’s edition of the Journal of the American Medical Association.

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