Improved cancer prevention and treatment in the past two decades has led to declines in both cancer deaths and diagnoses.
The number of cancer deaths in the U.S. has fallen steadily for two decades, with more than 1.3 million deaths avoided due to improvements in cancer prevention and treatment.
Declines varied by age, race, and sex, with the largest decreases seen among middle-aged men and women, compared to those 70 years and older. Middle-aged black men, in particular, experienced the most dramatic progress—an approximate 50 percent drop in the rate of cancer deaths in 20 years.
In spite of the significant drop in cancer death rates among black men, this group continues to have the highest incidence of cancer of any ethnic group in the U.S., double that of Asian Americans, who have the lowest rates.
The five-year survival rate of blacks also lags behind that of whites for several types of cancer, including uterine, oral, and urinary and bladder cancers.
This new data is presented in a report by the American Cancer Society, published in CA: A Cancer Journal for Clinicians.
In addition to looking at past data, researchers projected that the U.S. will see 1.7 million new cancer cases in 2014—around 4,500 new cancer diagnoses each day. They also expect that this year there will be 585,720 deaths—about 1,600 each day—due to cancer.
Researchers also expect three cancers—prostate, lung, and colon cancer—to be the most common among men this year, accounting for almost half new cases and 46 percent of cancer deaths. Among women, the most common cancers—breast, lung, and colon cancer—account for half of the projected new cancer cases and deaths.
However, the actual number of cancer deaths may differ from the estimates due to advances in screening and treatment.
“Low-dose CT lung [cancer] screening is projected to result in a 14 percent decrease in mortality,” says Andrea McKee, M.D., Chair of Radiation Oncology at Lahey Hospital & Medical Center. “This will have a large impact on cancer statistics overall, given the burden of lung cancer diagnosis in the U.S.”
Cancer death rates rose for much of the twentieth century, peaking in 1991, after which they started dropping steadily. Tobacco use among men caused much of this early increase due to deaths from lung cancer.
Between 1991 and 2010, men and women saw similar annual declines in cancer deaths—1.8 percent and 1.4 percent, respectively. Women, however, lost ground after 2006, with cancer deaths among men continuing to drop while holding steady among women.
“This is likely due to the fact that smoking prevalence among women peaked 20 years later than men, and there has been a slower quit rate seen among women than men,” says McKee. “Given the high prevalence of lung cancer in this country (more than one-quarter of all cancer deaths are due to lung cancer), any changes in lung cancer incidence and mortality will have a fairly profound impact on the overall statistics.”
The authors of the paper also noted that deaths from breast cancer among women have not decreased much since 2003.
In spite of the overall decline in cancer deaths, the number of cases increased for several types of cancer, including melanoma skin cancer, thyroid cancer, liver cancer, and kidney cancer. The largest annual increases were in thyroid cancer—5.4 percent for women and 6.5 percent for men.
Cancer continues to rank among the top causes of death for both men and women in the U.S.
“Although overall cancer is the second leading cause of death after heart disease,” says McKee, “within 20-year age groups, cancer is the leading cause of death for adults aged 40 to 79. Among females specifically, cancer is the first or second leading cause of death in every age group.”
While advances in cancer treatment over the past two decades have helped people survive a cancer diagnosis, screening and early detection programs have also helped doctors find malignancies early, when they can be more easily treated.
“It is clear from the trends that mortality rates are impacted by trends in screening,” says McKee.
For example, among women, improved screening for cervical cancer led to an 80 percent decrease in uterine cancer deaths between 1930 and 2010.
“Similarly, mortality decreases observed in colon, prostate, and breast cancer are due in large part to early detection through screening,” says McKee.