美国国家公共电台 NPR Cancer Death Rate Falls As Lung Cancer Picture Improves : Sho（在线收听）

ARI SHAPIRO, HOST:

Cancer death rates in the United States recently dropped more sharply than ever, according to an analysis by the American Cancer Society. NPR science correspondent Richard Harris reports on what's driving the trend.

RICHARD HARRIS, BYLINE: Cancer death rates in the United States have been falling gradually for about three decades. Rebecca Siegel at the Cancer Society has just finished crunching the latest data through 2017.

REBECCA SIEGEL: We had the biggest single-year drop ever.

HARRIS: Death rates dropped by more than 2% in a single year. And she points to one primary reason.

SIEGEL: It seems to be driven by accelerating declines in lung cancer mortality, which are very encouraging because lung cancer is the leading cause of cancer death in the U.S., causing more deaths than breast, colorectal and prostate cancers combined.

HARRIS: People with advanced lung cancer still have a gloomy outlook. Most will die within five years of diagnosis, and most smokers don't follow through and get screened to catch cancer early, despite official recommendations to do so.

SIEGEL: It probably is more the steady reductions in smoking, along with these treatment advances in the past decade, that have come together to create a perfect storm.

HARRIS: The story is not as positive for breast cancer and colorectal cancer, Siegel says.

SIEGEL: Progress has slowed a bit, although rates are still declining. And for prostate cancer, the rapid declines in death rates of the past couple of decades actually halted.

HARRIS: Siegel says that may in part be because health officials have changed their views about a common blood test called a PSA. Extensive use of that test led to many needless surgeries and complications because it identified many cancers that were actually never going to cause harm. But ratcheting back that test has also meant finding fewer cancer cases, Siegel says.

SIEGEL: I think there is a big need for a better test.

HARRIS: And despite the downward trend in cancer rates, the U.S. population is aging, which means there are more older people at risk for cancer every year and more deaths from the disease.

SIEGEL: So we have more than 600,000 deaths from cancer in this country every year, and that number continues to grow.

HARRIS: And with treatments getting progressively more expensive, that's a problem not just for individuals but for the entire health care system.

Richard Harris, NPR News.