Story by Jennifer Nichols, Seven News.

Cancer survivors who've suffered serious side-effects from radiotherapy are being offered new hope of a normal life

Brisbane's Wesley Research Institute is trialling high pressure oxygen treatment, with remarkable results.

After being diagnosed with prostate cancer, intensive radiation treatment left father of five John Stead with stressful, debilitating bowel problems.

John joined an international hyperbaric medicine study at Brisbane's Wesley Research Institute, where Dr Ken Thistlethwaite said the breakthrough treatment "allows the growth of new healthy tissue where there was previously scar tissue".

The process involves breathing in pure oxygen in a pressurised room, which increases oxygen absorption in tissue damaged by radiation.

To gather proof the technique works, doctors studied patients who'd suffered pain or bleeding after radiation treatment for ovarian and prostate cancer.

Of 150 patients worldwide, 89 per cent either healed or had significant improvement.

Five years after he first stepped into the hyperbaric chamber John's life is dramatically changed for the better.

"I think you've got to have been there to understand it," Mr Stead said.

"It's put my life back to the way it was prior to being diagnosed with cancer."

The results have been so promising, the Wesley Research Institute is now funding a further study for survivors of voice box and bladder cancer with radiation tissue damage.