AURORA, Colo. -- Radiation has been used to treat cancer for decades, but one of the challenges facing doctors was how to ensure that the patient was receiving the appropriate dose.

New technology is making dose measurement easier.

Mary Ann Gofigan goes to the University of Colorado Cancer Center five days a week for breast cancer radiation treatment. And thanks to the breakthrough Smart Marker, she and her doctors know that the dosage she’s receiving is correct and that the targeting is precise.

"It’s a pretty significant advance," said Dr. Rachel Rabinovitch, a radiation oncologist at the University of Colorado Cancer Center. "It's real time in vivo dosimetry, which means it’s in the patient measuring every specific treatment."

The hospital is the first in the western United States to use the Dose Verification System Smart Marker which is a thin glass capsule measuring the length of a nickel. The Smart Marker was implanted at the same time Mary Ann’s malignant tumor was removed. A detection paddle is used to read the wireless sensor before and after each radiation treatment, and for the first time it allows doctors to verify the treatments they are delivering.

"This allows us to very accurately measure the radiation and ensure that we are giving high quality treatment," said Rabinovitch. "Too much radiation and you can have higher side effects and long-term complications, too little and we’re not treating the cancer effectively."

This is a concern for physician and patient alike.

"They are very exact but this was an added measure, this gave me more peace of mind that they knew how much I was getting and it was the right dosage," said Gofigan.

Rabinovitch says there have been a couple of instances where the patients' radiation dose needed to be adjusted as indicated by the Smart Marker.

"It allowed us to modify a patients' plan and correct it, and we wouldn’t have known that otherwise," said Rabinovitch.

This technology is quality assurance for maximizing the therapeutic effect of the radiation.

"It’s like medicine, you know how much you take, you measure it, and this is measurable so it’s a good thing," said Gofigan. The U.S. Food and Drug Administration has approved the Dose Verification System for use in breast cancer patients and prostate cancer patients whose prostate is intact.