An already commonly used drug may help slow the growth of prostate cancer tumours in men who've been advised to take a wait-and-see approach to their disease.
Among many of the Canadian men diagnosed every year with the disease, their cancer is growing so slowly that the disease may never threaten their lives.
That's why doctors often advise these men to skip surgery, because not only is it unnecessary, it can help avoid many of the potential side effects of prostate surgery, such as incontinence.
But the "watchful waiting" approach is often a hard sell for many men, who feel they should do something about their cancer.
Now some Canadian researchers say they have found a way to make watchful waiting more bearable: an inexpensive drug that appears to slow the growth of tumours.
The drug is called Avodart (dutasteride) and it's already widely used to shrink enlarged prostates. Dr. Neil Fleshner of Princess Margaret Hospital in Toronto recently reported to the American Society for Clinical Oncology that the drug also seems to delay prostate tumour growth in some men with slower-growing cancers.
"We're cautiously extremely optimistic that this might represent an entire new treatment paradigm for patients around the world," Fleshner told CTV News.
Fleshner's team tested the drug in some 300 men with low-risk cancer confirmed by a biopsy. The men were given either daily Avodart or placebo pills. They then underwent new biopsies 1-1/2 and 3 years later.
The prostate cancer got worse in 38 per cent of men taking Avodart and 49 per cent of those on placebo pills. Final biopsies showed no signs of cancer in 36 per cent of men on Avodart versus 23 per cent of those on dummy pills.
Doctors say the fact that they couldn't even find the cancer when new biopsies were done shows how tiny many of these cancers were to start with.
Researchers gave no details on side effects observed in the study, but said no new ones appeared that haven't already been seen in current Avodart users. Avodart can sometimes cause sexual problems, such as impotence. It can also cause breast tenderness.
The study was sponsored by Avodart's maker, GlaxoSmithKline.
Doctors say since many men with early prostate cancer rush into surgery, this drug treatment may make more men comfortable with "watchful waiting."
"It is very reassuring to men to say actually we are not doing nothing if you go on this pill we are actually taking some steps to slow the progression of the disease stabilize, or even kill off some of the cancer cells," said Dr. Laurence Klotz of the Canadian Prostate Cancer Association, who was not involved in the study.
Veteran political organizer John Laschinger was part of the study. He uses the medication in hopes it will keep his cancer in check. So far, it's worked: Laschinger says his tumour remains small, and not a threat.
"I hope I die with the disease, not because of it," he says.
With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip
