Cancer deaths in the United States fell by 1.7 percent between 2014 and 2015, contributing to a 26 percent decline over the past two decades, according to the annual statistics report released this week by the American Cancer Society (ACS). The drop is largely attributable to declines in breast, colon, lung and prostate cancers, which together account for 45 percent of all cancer deaths.

Cancer incidence, or new cases, decreased over the past decades among men and remained stable among women, according to the report. Yet about 40 percent of men and 38 percent of women in the United States are expected to develop cancer in their lifetime.

Each year the ACS compiles updated statistics on new cancer cases, cancer-related deaths and disparities in cancer incidence and mortality. The 2018 report, by Rebecca Siegel, MPH, and colleagues from the ACS Surveillance and Health Services Research program, includes incidence data through 2014 and mortality data through 2015.

Based on the latest data, the report projects that there will be 1,735,350 new cases of invasive cancer (about 4,700 new diagnoses per day) and 609,640 cancer deaths (about 1,700 per day) in the U.S. in 2018. This does not count nearly 64,000 cases of breast carcinoma in situ, or not spread beyond its site of origin, and more than 87,000 cases of noninvasive melanoma of the skin.

Experts say the decline in cancer mortality—reflecting approximately 2.4 million fewer deaths—is largely due to a reduction in smoking, especially among men. Lung cancer alone is responsible for about a quarter of all cancer deaths. Earlier detection and advances in treatment also play a role.

“This new report reiterates where cancer control efforts have worked, particularly the impact of tobacco control,” said ACS chief medical officer Otis Brawley, MD. “A decline in consumption of cigarettes is credited with being the most important factor in the drop in cancer death rates. Strikingly though, tobacco remains by far the leading cause of cancer deaths today, responsible for nearly three in 10 cancer deaths.”

Overall, cancer is the second leading cause of death for both men and women in the United States, after cardiovascular disease. However, it reaches number one in some population subgroups, including Latinos and Asian Americans. Cancer accounted for 22 percent of the 2.7 million U.S. deaths in 2015, but it was the only one of the 10 leading causes of death that declined from 2014 to 2015, according to the report.

Survival is highest for prostate cancer (99 percent), melanoma of the skin (92 percent) and female breast cancer (90 percent), and lowest for lung cancer (18 percent), liver cancer (18 percent) and pancreatic cancer (8 percent), which tend to be diagnosed at more advanced stages. Blood cancers saw some of the biggest improvements in survival thanks to the development of targeted therapies; for example, five-year survival with chronic myeloid leukemia increased from 22 percent in the mid-1970s to 68 percent by 2013.

Cancer Disparities

The most common cancer types among men are prostate, lung and colorectal cancers. Prostate cancer accounts for about one in five new cancer diagnoses in men, but prostate cancer mortality has fallen by 52 percent since 1993, according to the report. Lung cancer deaths among men dropped by 45 percent between 1990 and 2015.

The most common types among women are breast, lung and colorectal cancers. Breast cancer accounts for 30 percent of new diagnoses, but deaths have fallen by 39 percent since 1989 due to earlier detection and treatment. Women—who started smoking in large numbers later than men—saw a 19 percent decline in lung cancer deaths between 2002 and 2015. Cervical cancer remains a leading cause of cancer death among women in the 20-to-39 age group, showing that many are still not getting the recommended screening and human papillomavirus (HPV) vaccination.

Colon and rectal cancer mortality for both men and women has been cut in half since 1970 due to a reduction in risk factors and increased screening and improved treatment, but the death rate has recently started to creep up among people younger than 55.

The report notes that liver cancer is rising rapidly among women, though it is stabilizing among men. The authors suggest that this may be due to the prevalence of hepatitis C among aging baby boomers (those born between 1945 and 1965). Expanded hepatitis C virus screening and treatment with new well-tolerated antivirals can lower the risk of developing hepatocellular carcinoma, the report authors emphasize.

An estimated 10,590 children ages 1 to 14 will be diagnosed with cancer and 1,180 will die of cancer in 2018, according to the report; in this age group leukemia is the most common type of cancer. Cancer is the second most common cause of death for children, after accidents.

The ACS report shows some stubborn disparities with respect to race, ethnicity and geographic region.

African Americans have both higher cancer incidence and mortality compared with white people. In 2015, the cancer death rate was 14 percent higher among Blacks than among whites overall. But the disparity was much smaller among Black people older than 65 than among younger people (7 percent versus 31 percent), which the report authors attribute to the fact that universal access to Medicare for seniors helps overcome differences in access to care.

For all cancers combined, the five-year survival rate is 68 percent among white people and 61 percent among African Americans, the report says. Blacks are more likely to be diagnosed at advanced stages of cancer, but even after adjusting for sex, age and stage at diagnosis, African Americans had a 33 percent higher risk of death after a cancer diagnosis than whites, and Native Americans were 51 percent more likely to die of cancer.

“Cancer occurrence and outcomes vary considerably between racial and ethnic groups, largely because of inequalities in wealth that lead to differences in risk factor exposures and barriers to high-quality cancer prevention, early detection and treatment,” the report authors concluded.

Click here to read an ACS press release about the report.

Click here to read the full report.

Click here for the latest ACS Cancer Facts & Figures.