Doubts Arise on a Test To Detect Cancer Signs
Published: April 10, 1990
BOSTON, April 9— Four years ago, a test that seemed to detect all forms of cancer from tiny blood samples appeared destined to revolutionize the way doctors screen people for the disease.
Now, many specialists doubt the method will ever live up to its promise. For reasons they cannot explain, the test seems to work only in the hands of the physician who invented it.
The physician, Dr. Eric T. Fossel of Beth Israel Hospital in Boston, said in 1986 that he had found a way to tell whether a person had cancer simply by examining a bit of the patient's blood in a nuclear magnetic resonance scanner. It would detect tumors too small to feel or spot on X-rays.
Dr. Fossel continued to work on the method and reported more encouraging results as he tested thousands of blood samples. The discovery was so important that many other doctors hurried to try it out. Apparently without reported exception, they failed.
Two studies published in the current issue of The New England Journal of Medicine add to the mounting evidence against it. ''We were unable to determine whether or not a person had cancer based on the blood test,'' said Dr. Paul Okunieff of Massachusetts General Hospital.
Carefully mirroring Dr. Fossel's methods, Dr. Okunieff tested blood from 79 people with cancer or pre-cancerous diseases and 66 people in the hospital for other reasons. The test could not tell them apart.
Another researcher, Terje Engan, directed a Norwegian group from the University of Trondheim that conducted a similar comparison of blood from 104 cancer patients and 164 healthy people. When the people studied were the same sex and age, the test could not distinguish those with cancer from those without.
Test Works for Only One Man
In his report, Dr. Okunieff reviewed 18 studies, including his own, that used nuclear magnetic resonance scanners to diagnose cancer. Only six, all by Dr. Fossel, worked. In one of those studies, published last year, doctors from the West German Cancer Center in Essen sent blood samples to Dr. Fossel from 54 men with testicular cancer, 88 men who had been successfully treated for the disease and 57 healthy men the same age.
Dr. Fossel, who had no information about the patients' status, conducted the nuclear magnetic resonance tests and sent back the results. The German doctors found that Dr. Fossel's findings were 90 percent accurate.
So the question remains: How can a test work for one person but nobody else?
''I honestly don't know what went wrong, but there is this big difference between what he's getting and what other people reported,'' said Dr. Robert Shulman of the Yale University School of Medicine.
Dr. Fossel refused to discuss the latest reports but issued a statement implying that others have not duplicated his results because they failed to follow his methods faithfully.
''Clearly, the NMR cancer blood test requires close adherence to the specified techniques,'' he wrote, ''but when carried out correctly, this method is a candidate system for detection of cancer as well as for monitoring cancer therapy.''
At the National Cancer Institute, which has financed some of Dr. Fossel's research, Dr. Roger Aamodt said he was ''reasonably sure'' that the test would not be suitable for general cancer screening. However, he said it might still be of some benefit in checking the progress of treatment or recurrence in some individual cancer patients.
Dr. Aamodt said no one knew why the test seemed to work only for Dr. Fossel. While it is possible that the reasons have to do with differences in techniques or the patient populations studied, the explanations are ''essentially all supposition and speculation,'' he said.
Dr. Aamodt and Dr. Okunieff said they thought Dr. Fossel had honestly tried to obtain accurate results.
''We are still in a position where it is up in the air,'' said Dr. Aamodt. ''This has been a controversial area since the first finding. A lot of people looked at this and said it didn't make sense. All along there have been questions. What you are seeing is science in action.''