Detecting Cancer Earlier
When laboratory tests say there's a good chance you have cancer, but a biopsy doesn't turn up anything, what can you do? Should you wait it out, wondering whether a hidden cancer is growing undetected?
A relatively new alternative may allow people to find out whether they have cancer before it becomes obvious, reports Correspondent Jaine Andrews of CBS News affiliate KELO-TV in Sioux Falls, S.D.
The device is referred to as a PET scan. PET stands for positron emission tomography.
"This high-powered machine, technology, will tell me whether or not I have cancer," says 82-year-old Don Johnson.
Johnson may have lung cancer. X-rays show a mass on his lung, and he has had both a CAT scan and a biopsy.
"I thought they would know," Johnson says. "Well, they don't know for sure."
Johnson is given an injection of a radioactive isotope, or radioactive sugar.
Here's how it works: Because cancer cells feed on sugar, they will instantly attach themselves to the radioactive substance injected into Johnson's body.
The scanner maps a 3-D image of the patient, revealing the body's metabolic processing of the sugar injection.
"No allergic reactions, no drug effects, no invasive procedures at all," says Dr. Fred Lovrien of Nuclear Imaging, Ltd.
To bring PET scans to people in rural areas of North Dakota who otherwise would not be treated at local hospitals, Nuclear Imaging has put the technology on wheels - transporting the equipment in a semi-truck.
The machine itself looks like an ordinary CAT scan, and Johnson is placed inside a tunnel that will allow the device to take a reading of his entire body. But this machine can see
what no CAT scan can - and works more quickly.
"A lot of the other procedures that are done, like CAT scanning and MRI and ultrasound and X-rays look at anatomy," says Dr. W. Allan Boade of Nuclear Imaging.
They tell you only that something is there, not what it is or what it's doing.
"There are times when this is gonna say: We don't have to do surgery. Or we should do chemotherapy or some other form of treatment," Boade says.
The PET scan can find a cancer as small as half an inch. Nuclear Imaging's machine, made by CTI Inc. of Knoxville, Tenn., costs $2 million, and the test will cost patients about $1,800.
Five years ago the machine cost about $6 million, a prohibitive price for medical centers that weren't research facilities or university hospitals. Since then, the technology has become cheaper and more hospitals are able to purchase it.
Eighty percent of the scans are used to look for cancer, but the PET scan can also test for heart damage, Alzheimer's disease, Parkinson's syndrome and epilepsy.