The Vancouver Sun
Tuesday 11 June 2001

Cancer agency seeks funds for popular PET scan

Experts say the technology could save money by stopping unnecessary treatment.
Pamela Fayerman Vancouver Sun

Despite the $2,500 price tag, the number of PET scans on cancer patients has skyrocketed more than 300 per cent in the eight months since Canada's first private diagnostic clinic offering the advanced technology opened in Vancouver.

But with a fund from a philanthropist used to cover the cost of the scans for the neediest patients quickly drying up, the B.C. Cancer Agency is readying a pitch to the provincial government to publicly fund Positron Emission Tomography scans on the grounds that they offer a true advantage over other imaging technology like MRIs, CTs and x-rays in many circumstances.

At a conference Monday, oncologists and nuclear medicine specialists gathered to draft clinical guidelines on using PET scans in the early diagnosis, monitoring and followup of cancer patients.

Unlike CT or MRI scans, which image anatomical structures in the body, PET scans peer into the body's chemistry to provide a view of metabolic activity and function within cells and tissues. Traditionally, a biopsy has been needed to tell whether a tumour is cancerous, but a PET scan can often tell whether a tumour is benign or malignant--and whether the cancer has spread--without surgery or other invasive procedures.

It does that with the use of radioactive, sugar-based tracing agents injected into the patient. The PET scanner detects signals from the tracing agents as they are taken up in diseased parts of the body. A computer then assembles the signals into three-dimensional images that show biological functions.

"The conference is validating the use of PET in oncology and is helping to define the application of this technology in Canada's health care system," said Denis Tusar, the Vancouver architect who established the $4-million PETscan Centre at the B.C. Research and Innovation complex at the University of B.C.

In its first month of operation last October the clinic conducted a dozen scans. By last month, that number had swelled to 51.

Dr. Simon Sutcliffe, chief executive officer of the B.C. Cancer Agency, said it is "inconceivable that PET scans won't become the imaging modality of choice" in many cases. Previously, the cancer agency sent patients to Seattle for scans, using funds from a $150,000 trust fund set up by a donor to help those who could not afford to pay for it themselves. But with the fund soon to be depleted, Sutcliffe said his goal is to persuade government "in a responsible way" to establish a fund to cover the scans.

"We're here to define which patients need this state-of-the-art technology and to define the proven indications," he said in an interview at the conference, held at the Morris Wosk Centre for Dialogue at Simon Fraser University's downtown campus.

Because it is a new and expensive technology, doctors know they have to prove to governments (and in the U.S., to private insurers) that PET scans are cost effective.

Dr. Richard Wahl, director of the division of nuclear medicine in the radiology department at Johns Hopkins in Baltimore, said without PET scans, many cancer patients may undergo unnecessary treatment.

So PET scans can be cost saving because they eliminate unneeded procedures and treatments such as surgery, chemotherapy or radiation.

Indeed, research studies done over the past decade indicate that doctors have changed their treatment approach in up to 50 per cent of cases in which a PET scan was done.

Wahl said when a PET scan shows cancer has spread to the bones and throughout the body, surgery shouldn't be deemed as potentially curative and so palliative care would then be the approach to be taken.

Though it has not yet been proven to be better than less expensive imaging techniques for many less common types of cancer, PET scans are highly sensitive and specific in cancers found in the lungs, breast, colorectal, head, neck and gynecological areas.

Instead of a series of blood tests, x-rays, ultrasounds, and MRIs, the PET scan can diagnose disease, stage it, determine if the cancer treatment is working and whether cancer has recurred.

The technology is not without its weaknesses, however, as some experts at the conference noted the relatively high false-positive rate for some cancers and the fact that the tracing agents sometimes find elevated metabolic activity in benign tumours or in parts of the body that are infected or inflamed.

Although researchers are studying the use of PET scans in neurology and cardiology, the vast majority of scans are done on cancer patients. A B.C. Cancer Agency study estimates, for example, that if, as projected, there are 2,200 cases of colorectal cancer in the province this year, there are 100 potentially curable and ideal candidates for PET scans whose cancer wouldn't be detected without PET.

Sutcliffe said with a total of nearly 20,000 newly diagnosed cancer patients each year in B.C., a conservative estimate of the number of PET scans that could--and should--be conducted is 8,000. Since each clinic can perform about 2,000 scans per year, Sutcliffe said it is feasible that more PET scan clinics could open.

As to whether clinics are publicly funded or are private-public partnerships, Sutcliffe said he has no preference, just as long as his patients get access to them.

Sun Health Issues Reporter
pfayerman@pacpress.southam.ca

This article was downloaded from www.vancouversun.com and appeared in the Vancouver Sun, Tuesday, June 11, 2001, on page A3