Ken Morris, who has early-stage prostate cancer, chose to undergo a new procedure at a private clinic in Toronto. (CBC)

Some men with prostate cancer are paying for a new treatment to target cancer cells called high intensity focused ultrasound, which is less invasive than surgery or radiation.

HIFU, which was developed in the United States about 10 years ago, is a computer-controlled probe that is inserted into the rectum and emits ultrasound beams inside the prostate where it creates enough heat to destroy targeted tissue.

A few months ago, Ken Morris was diagnosed with early-stage prostate cancer and elected to undergo the procedure at a private clinic in downtown Toronto that offers the less-invasive treatment.

"That was one of the first qualities of HIFU that attracted me to it," he said. "No cutting, no stitching."

Morris was a candidate for the procedure because his cancer was not aggressive. He was sold on the promise of fewer side effects commonly associated with prostate surgery despite the hefty $20,000 fee.

"The likelihood of erectile dysfunction seems to be somewhat lower," said Dr. Laurence Klotz, a urologist at Sunnybrook Health Sciences Centre in Toronto. "We can do a nerve-sparing HIFU treatment, which really doesn't treat the nerves at all, and the rate of incontinence or difficulty controlling the urine also seems to be significantly lower than with surgery."

About 7,000 men around the world have undergone the treatment. Early studies suggest most patients emerge cancer-free but there is very little extensive, long-term data.

Dr. Joseph Chin, a urologist at London Health Sciences Centre in London, Ont., is doing a clinical trial using HIFU and looking at whether it is safe, effective and extends the lives of men for whom radiation therapy hasn't worked.

"We really need to go for up to five years, 10 years, before we know long-term … whether these patients are 'cured,'" he said.

After recently undergoing the procedure, Morris said HIFU was the best choice for him.

"I'm very pleased that I'm feeling so good, sitting at my house, talking to you normally right now," he told CBC News. "That's one thing I didn't expect. I expected to feel a lot worse."

Morris won't know for weeks whether he is free of cancer, but he said he has no regrets about his decision to try HIFU.