A Brisbane hospital has become the first facility in Queensland to use a new technique to help improve radiation therapy for breast cancer sufferers.

Queensland women battling breast cancer are now less likely to suffer harmful doses of radiation to their hearts during therapy thanks to a new treatment technique.

Brisbane's Princess Alexandra Hospital is the first facility in Queensland to use Deep Inspiration Breath-hold (DIBH), which involves patients breathing deeply through a snorkel-like device while receiving therapy so physicians can better time radiation doses.

Essentially, therapists wait until the patient is holding their breath to deliver the radiation so the heart and lungs are as far from the firing line as possible.

"This is a good news story as ladies with breast cancer are living longer," Associate Professor Margot Lehman said.

"We need to be looking at the quality of the survival."

Ass Prof Lehman said there were plans to roll out the technique - which is already used in Europe, the US and southern Australian states - across Queensland.

But it can only be used on women with left-sided breast cancer and "favourable anatomy", she clarified.

Sue Hewlett, 59, has just wrapped up six weeks of therapy using the deep breathing technique to target her breast cancer.

She said breathing into the snorkel apparatus was challenging at first because she'd just completed a gruelling course of chemotherapy but she eventually got used to it.

"I just had to really concentrate," the one-time Princess Alexandra Hospital nurse said.

"It's a little bit uncomfortable, having your nose pinched and having something in your mouth for sometimes up to 15 minutes."

But it's worth it to protect her heart given a family predisposition to heart disease, she said.

Having now finished her treatment, she feels brighter, and plans to celebrate alongside her husband, who has just retired.

"We'll go away on a holiday and rest and relax," she said.