A Leading Cause of Death, but Less So [NYT]
By GINA KOLATA
Published: April 15, 2007
Last month, Elizabeth Edwards’s breast cancer recurred. Then Tony Snow, the president’s press secretary, said his colon cancer was back. On Wednesday, Fred Thompson, the former Republican senator from Tennessee and a possible presidential candidate, said he has had lymphoma.
News about cancer, it seems, is everywhere. But, as statisticians readily explain, impressions can be misleading. While cancer remains the second-leading killer of Americans, behind heart disease, and while no one would make light of the toll from the disease, cancer deaths are on the wane.
The National Cancer Institute reports that death rates have been declining since the early 1990s. The most recent data, from 2002 through 2004, show death rates falling by 2.6 percent a year for men and 1.8 percent a year for women.
Men have more cancer and higher cancer death rates than women, notes Brenda Edwards, a statistician at the cancer institute, but part of the reason the death rate fell so much for men is that more of them have stopped smoking. Lung cancer is the biggest cause of cancer deaths in men and women.
Other reasons for the decline in the cancer mortality rate in men and women, Dr. Edwards says, include better treatment, better care, and earlier detection.
In men, death rates fell for 12 of the 15 most common cancers, including those of the lung, colon and rectum, and prostate. And, for women, death rates fell for 10 of the 15 most common cancers, including cancers of the breast, colon and rectum, cervix, and the ovaries.
Cancer incidence has been flat recently, the cancer institute reports. But incidence is harder to interpret than mortality, explains Eric Feuer, a statistician at the cancer institute. One reason is cancer screening. The harder doctors look the more cancer they will find.
For example, prostate cancer rates rose by an unprecedented 16.2 percent a year from 1988 to 1992. The reason was that the P.S.A. test, a blood test for prostate cancer, was coming into widespread use and finding cases that otherwise might not have been found for years, if ever.
Once all those cancers were found, there was less to find when the same men were tested in subsequent years. Incidence fell by 10.2 percent a year from 1992 to 1995. Now it is flat.
For statisticians like Dr. Feuer, though, the death rates tell the real story and the story is heartening.
“I was here at the N.C.I. when mortality was fairly flat,” he recalls. “There was a lot of effort, but now it’s finally coming to fruition.”
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