Editorials
Why Cancer Deaths are Dropping Dramatically
By Nancy A. Ferrari
Each year, the American Cancer Society (ACS) evaluates recent trends in cancer diagnoses, survival rates, and deaths. Last year’s analysis showed that 369 fewer people died of cancer in 2003 than in 2002. This year, the data reveal an even more dramatic drop. In 2004, cancer took 3,014 fewer lives than it did in 2003.
The report, released in mid-January of 2007, goes on to put a face to this very encouraging trend. For men, lung cancer death rates falling, and after creeping up for decades, leveling off for women. Researchers believe that this reflects differences in historical smoking patterns between the sexes. Women’s tobacco use peaked nearly 20 years after it did for men, so the downward trend in lung cancer deaths is lagging as well.
Breast cancer rates appear to be holding steady after creeping up since 1980. "What has changed significantly," said Donald P. Braun, Ph.D., vice president of clinical research at Cancer Treatment Centers of America, "is more widespread use of screening mammography. Today, roughly 80% of women get screened, compared to only 50%-60% 10 years ago."
What’s more, improved therapies for advanced breast cancer mean that women with the disease are living longer. "Thanks to early detection, more breast cancers are discovered when they are still curable and better therapies for advanced disease mean longer survival times. Together, these factors collaborate to bring down the annual number of breast cancer deaths," said Dr. Braun.
An increasing number of men are being diagnosed with prostate cancer, but this is in part to vigilant PSA screening. Rates of colorectal cancer are falling for both sexes. In fact, the drop in cancer deaths from 2003 - 2004 is primarily the result of fewer colorectal cancer deaths in both sexes. Improvements in early detection and treatment helped reduce death rates from breast, prostate, and colorectal cancers.
Amid the excitement over these numbers, clearly much work remains. In its yearly report, the ACS also predicts cancer prevalence and deaths for the coming year. In 2007, researchers expect that, the most common cancer diagnoses in men to be, in order of prevalence: prostate, lung, and colorectal cancer. In women, the top three cancer diagnoses will be breast, lung, and colorectal cancer. The most deadly cancer may come as surprise. For many men, prostate cancer is a big worry; for women, breast cancer. But it is lung cancer that will be the leading cause of cancer deaths for both sexes. Although more women will be diagnosed with breast cancer, lung cancer continues to bear the dubious distinction of killing more women than breast cancer and colorectal cancer combined. The National Lung Cancer Screening Trial is underway to evaluate whether screening smokers and past smokers will help reduce lung death cancer deaths. It will compare standard X-ray and spiral CT scans to see which may provide the best way to detect early disease.
Not an Equal Opportunity Killer
Cancer is not an equal opportunity killer. African-American men are 15% more likely to develop cancer and 38% more likely to die from it when compared to White men. African-American women are 9% less likely than White women to develop cancer, but are 18% more likely to die from it. Why? Late diagnosis, differences in risk factors, inadequate health care, and even specific tumor characteristics may all play a role.
The authors caution that any statistics on cancer prevalence and death rates must be interpreted carefully. Numbers normally fluctuate from year to year and may be skewed by small study populations. And it’s difficult to know just how many people have been diagnosed with a specific cancer because not all states have complete cancer registration. But there is no question that the numbers reinforce the value of early detection and the importance of continued research on more effective treatment strategies.
-- Nancy Ferrari is a medical writer based in the Boston area.