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Debate Over Lung Cancer Test

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If a simple, painless test can find the world's deadliest cancer when it is smaller than a pea — and such a test does indeed exist — shouldn't people who are most at risk have one?

Surprisingly, the federal government, American Cancer Society and a raft of cancer specialists say the answer is "no."

They are waging an uphill battle as frightened current and former smokers rush to get a special kind of X-ray that other physicians are urging for lung cancer detection but that has not yet conclusively been shown to save lives.

A huge federal study is under way to see if it can, and answers may come as soon as next year. In the meantime, it's generating a classic "can't wait for science" stampede.

The clamor rose last week with the deaths of newsman Peter Jennings and "Dallas" star Barbara Bel Geddes, and the news that "Superman" widow Dana Reeve has lung cancer.

Patricia Dowds and her husband, David Byrom, psychologists from Long Island, are among the many former smokers who voted with their wallets and had the $300 test on Friday.

"We do it for our own peace of mind," Dowds explained.

No one disputes that the test, called a spiral or helical CT scan, detects lung abnormalities as small as 5 millimeters — less than a fifth of an inch.

The argument is over whether that's a good thing.

For every cancer these scans detect, many more "false positives" occur — harmless bumps and lumps leading to painful, expensive and unnecessary biopsies and surgeries. Complications can include lung collapse, bleeding and infection.

"The concern that we have is false positive rates," which range from 25 percent to as high as 60 percent, said Tom Glynn, the cancer society's director of science and trends. "What we don't want to do is create even more anxiety" by backing a test that is so imprecise, he said.

Even when cancers are found, experts argue about whether that's a benefit or a risk. No one knows how many of these tumors are so slow-growing that they pose less of a health threat than the surgery, radiation and chemotherapy used to treat them.

However, screening proponents say there's no mystery about how deadly the disease is, and that survival improves the sooner it is detected. About 172,570 Americans will be diagnosed with lung cancer this year and almost as many, 163,510, will die of it.