Canadians have virtually no access to the most advanced diagnostic test in the world, considered by health experts to be the best tool for detecting certain cancers early and determining how far tumours have spread.

The technology in question, Positron Emission Tomography (PET) scans, uses radioactive drugs to detect cancer. A number of studies indicate this scanner is highly effective in detecting cancer.

But with a cost of between $1.5-million and $3-million per machine, plus hundreds of thousands of dollars in maintenance each year, provincial governments have been slow to adopt the state-of-the-art technology.

There are only three public PET scanners in Canada -- in Hamilton, Ont., Sherbrooke, Que., and Edmonton (which operates just one evening a week). There are more than 250 in the United States. The machines are also commonly used in Germany, Japan and Australia.

The Edmonton machine will be fully operational by April. "And I have no indication that the government is prepared to put operating dollars into it, so it may just sit there, a lump of metal doing nothing in a very nice building," said Dr. Sandy McEwan, head of the Canadian Association of Nuclear Medicine.

"In the United States, it would be considered malpractice not to do a PET scan on someone suspected of having lung cancer," added Dr. McEwan, an oncologist at the Cross Cancer Institute in Edmonton.

About 57% of Canadians believe the quality and quantity of medical technology in the United States is far superior or somewhat superior to that in Canada, according to a National Post / Global poll conducted by COMPAS Inc.

Patients with lung cancer, colon cancer, cancers in the head and neck, advanced breast cancer, lymphoma and melanoma can avoid some surgeries and invasive tests by having PET scans. For example, PET scans are 93% accurate in detecting the spread of lung cancer, compared with 63% for CAT scans.

A recent U.S. study shows doctors change the way they treat 60% of advanced breast cancer patients after viewing results from a PET scan. Physicians switched treatments because the PET results were more accurate in determining the spread of breast cancer than such traditional imaging technologies as CAT scans or MRIs.

A private company, International P.E.T. Diagnostics Inc., is taking advantage of the lack of scanners in the public system. Its first clinic, in Vancouver, charges $2,500 for the test and has attracted clients from as far away as Newfoundland. The company plans to expand its clinics to Toronto, Montreal and Calgary.

Other radiological procedures in Canada, such as CAT scans and MRIs, are funded by the public health-care system but the equipment is ageing and waiting lists have grown so long that private health companies are beginning to offer the services to those willing to pay for them.

"It is totally leaving the door open to privatization and that's what we have been seeing in the past three years," said Normand Laberge, executive director of the Canadian Association of Radiologists.

There are about 20 private MRI clinics in three provinces -- British Columbia, Alberta and Quebec -- and companies are looking to expand, possibly in Winnipeg and Halifax.

Clearly, private clinics -- offering expanded services and often the latest technology -- are establishing a stronger foothold in the health-care market. Just three years ago, they accounted for 1% of the MRI market; today, it is believed to be more than 10%.

One reason is hospital waiting times in Canada, on average, are 69% higher today than in 1993.

"We have very limited access to current modern imaging techniques in Victoria, particularly," said Dr. John Mathieson, head of radiology in Victoria's Capital Health Region. "For relatively routine tests in other parts of the world, we have a waiting list going beyond reason. Our waiting lists for MRIs and CAT scans is going into next summer. People are being booked for June and nobody even has calendars for next year yet."

St. Paul's Hospital in Vancouver started offering full-body CAT scans in August in the evenings for just less than $1,000 a test. A Montreal clinic offers a private CAT scan for $250. Wait times are minimal, one or two weeks, compared with backups as long as six months in the public system.

Without prompt access to such procedures, said Dr. Mathieson, many patients undergo surgery or other treatments when it is too late to correct problems. "It means they are suffering for months without having a diagnosis made and treatment done. That is just normal in Victoria right now."

It is not a problem unique to British Columbia. In September, Quebec radiologists decided to charge patients a $4 user fee for every X-ray unless the province agreed to replace ageing equipment before the end of the year.

It is in direct violation of the Canada Health Act.

"This is Third World medicine in Quebec," Dr. Gaetan Barrette, president of the Association of Radiologists in Quebec, has said.

"I am absolutely positive that things are going to get worse," predicted Dr. Mathieson.

New data comparing medical equipment in economically developed countries, put together by the Fraser Institute, ranks Canada 19th of 25 countries in terms of MRI availability to patients, just ahead of Luxembourg, the Czech Republic, Hungary, Greece, Poland and Mexico.

In an examination of CAT scans per capita, the data determined Canada ranked 18th of 23 countries. Luxembourg and the Czech Republic moved ahead of Canada, though the United Kingdom ranked 20th.