The U.S. continues to see a decline in cancer mortality, according to the latest numbers published by the U.S. government on May 22 in Cancer. However, the figures also indicate a rising incidence of late-stage prostate cancer, possibly due to the decline in prostate-specific antigen (PSA) screening.
The "Annual Report to the Nation on the Status of Cancer" tracked cancer incidence and mortality in the U.S. for all major cancers from 1999. Researchers found that cancer death rates fell 1.8% per year for men and 1.4% per year for women. Between 2011 and 2015, death rates fell for 11 of the 18 most common cancers in men and for 14 of the 20 most common cancers in women (Cancer, May 22, 2018).
In addition to lower mortality rates, the researchers also found lower rates of cancer incidence, at least among men. Cancer incidence went from a 0.6% annual decline from 1999 to 2008 for men to a 2.2% annual decline from 2008 to 2014. Incidence rates for women were stable over the same period.
Death rates from breast cancer for women declined 1.6% on average per year from 1999 to 2015; breast cancer incidence fell before 2004 but has been rising since then at an average annual rate of 0.4%. In all, 78% of breast cancer cases are diagnosed at stage I or II, for which survival rates are high (100% and 92%, respectively). About 6% of cases are diagnosed at stage IV, for which the five-year survival rate is 26.5%.
| Change in U.S. annual death rates for 5 most prevalent cancers, 2010-2015 | ||
| Cancer type | Death rate per 100,000 | Average annual percent change |
| Men | ||
| Lung and bronchus | 53.8 | -3.8% |
| Prostate | 19.5 | -2.2% |
| Colon and rectum | 17.3 | -2.5% |
| Pancreas | 12.6 | 0.2% |
| Liver and intrahepatic bile duct | 9.4 | 1.6% |
| Women | ||
| Lung and bronchus | 35.4 | -2.4% |
| Breast | 20.9 | -1.6% |
| Colon and rectum | 12.2 | -2.7% |
| Pancreas | 9.5 | 0.2% |
| Ovary | 7.2 | -2.3% |
The report delved specifically into prostate cancer in a separate article in Cancer. The start of PSA screening in 1988 led to a sharp increase in prostate cancer incidence in the 1990s, until research studies began questioning how many cancers being detected were indolent and would never pose a health risk to men. Widespread PSA screening began declining, and in 2012 the U.S. Preventive Services Task Force (USPSTF) recommending against routine PSA screening.
But the pendulum has been swinging back in favor of at least some PSA screening. The USPSTF in 2017 recommended changing its guideline against screening, instead recommending that men 55 to 69 years old discuss with their doctors whether to get PSA tests.
Indeed, in this week's cancer report, researchers found indications that the drop in PSA screening could be leading to more late-stage disease.
"After a decline in PSA test usage, there has been an increased burden of late-stage disease, and the decline in prostate cancer mortality has leveled off," wrote Dr. Serban Negoita, PhD, of the U.S. National Cancer Institute (NCI) and colleagues.
The researchers also found higher mortality rates for several other cancers, including liver cancer, possibly caused by obesity and the prevalence of hepatitis C infection among baby boomers. Obesity is also thought to be contributing to higher death rates for uterine and pancreatic cancer. Finally, an increase in cancers of the oral cavity and pharynx among white men is believed to be related to human papillomavirus infection.
