Americans are dying from cancer at lower rates and living longer after being diagnosed with the disease than in years past, according to the latest Annual Report to the Nation on the Status of Cancer, which was released Friday.
For several cancers, the improvements in five-year survival rates were for both early and late-stage disease. That finding is important, for many experts believe that much of the improvement in cancer survival rates of recent decades has had more to do with earlier diagnoses than with more effective treatments.
The new report, which analyzed data collected through 2014, also found that the overall cancer incidence rates — the rates at which people are diagnosed with new cancers — has decreased in men, but remains unchanged in women.
“The continued drops in overall cancer death rates in the United States are welcome news, reflecting improvements in prevention, early detection and treatment,” said Betsy A. Kohler, executive director of North American Association of Central Cancer Registries (NAACCR), in a released statement. “But this report also shows us that progress has been limited for several cancers, which should compel us to renew our commitment to efforts to discover new strategies for prevention, early detection and treatment, and to apply proven interventions broadly and equitably.”
The report is a collaboration between the NAACCR, the American Cancer Society, the Centers for Disease Control and Prevention, and the National Cancer Institute.
Trends in death rates
The overall U.S. cancer death rate declined during the period 2010-2014 — by 1.8 percent per year in men, 1.4 percent per year in women and 1.6 percent per year in children, according to the report.
Those rates fell for 11 of the 16 most common types of cancer in men and for 13 of the 18 most common types of cancer in women, including lung, colorectal, breast (in women only) and prostate.
Death rates increased, however, for cancers of the liver (men and women), pancreas (men), brain (men) and uterus.
Across all racial and ethnic groups, lung cancer remains the leading cause of cancer death among men, and lung, breast and colorectal cancer remain the leading causes of cancer death among women.
Black men and black women have the highest cancer death rates of any racial or ethnic group, and Asian/Pacific Islander men and women have the lowest. The risk of dying from cancer varied significantly by race and ethnicity. That risk was 33 percent higher in blacks and 51 percent higher in American Indians and Alaska Natives than in whites, for example.
Trends in survival rates
The researchers also compared the five-year survival rates (the percentage of patients who live at least five years after their cancer is diagnosed) for people diagnosed with cancer in 1975-1977 with the rates for those diagnosed with the disease in 2006-2012.
“While trends in death rates are the most commonly used measure to assess progress against cancer, survival trends are also an important measure to evaluate progress in improvement of cancer outcomes,” said Ahmedin Jemal, a cancer epidemiologist at the American Cancer Society and the report’s lead author, in the released statement.
"We last included a special section on cancer survival in 2004, and as we found then, survival improved over time for almost all cancers at every stage of diagnosis," Jemal added. "But survival remains very low for some types of cancer and for most types of cancers diagnosed at an advanced stage."
Since the late 1970s, the cancers with the greatest increases in survival rates — increases of 25 percent or more — were leukemia, non-Hodgkin lymphoma, myeloma (cancer of the bone marrow), and prostate and kidney cancers.
Other cancers with significant increases in survival rates were thyroid cancer, melanoma, and breast cancer in women.
Breast cancer was also one of a handful of cancers for which the five-year survival rate for advanced disease significantly improved. In 1975-1977, 18.7 percent of women diagnosed with late-stage breast cancer were living five years after their diagnosis. By 2006-2012, that five-year survival rate had climbed to 33.6 percent.
The researchers also looked at the relative five-year survival rates for various cancers. Some researchers consider this a more useful measure of cancer survival, for it compares the five-year survival rate of people with cancer with that of the general population.
During the period 2006-2013, the cancers with the lowest five-year relative survival rates were pancreas (8.5 percent), liver (18.1 percent), lung (18.7 percent), esophagus (20.5 percent), stomach (31.1 percent) and brain (35 percent). Those with the highest were prostate (99.3 percent), thyroid (98.3 percent), melanoma (93.2 percent) and female breast (90.8 percent).
Among the data were some troubling racial and ethnic disparities. The relative risk of death for all cancers combined was 33 percent higher in blacks and 51 percent higher in American Indians and Alaska Natives than in whites.
“Much work remains in order to understand the likely multiple causes of these observed differences,” write the authors of the report.
Racial and ethnic disparities in being able to access treatment for cancer — particularly timely treatment — are among those causes, they add. Other research has shown, for example, that black women with breast cancer are less likely than white women to receive and be able to follow-through with chemotherapy treatments. They are also more likely to experience delays in receiving such treatments.
Trends in incidence rates
The report also looked at cancer incidence rates — the rates of newly diagnosed cases of the disease. It found that the overall rates decreased in men, but stayed the same in women.
The rates fell for seven of the 17 most common cancers in men and seven of the 18 most common cancers in women, including lung and colorectal cancers. The rates rose, however, for seven cancers in men and nine cancers in women, including myeloma, liver cancer, mouth cancer and thyroid cancer in both men and women and pancreatic cancer in men.
Some of those increases in incidence rates probably reflect better methods of detecting cancer, the authors of the report point out. “For example, the continued increase in melanoma and thyroid cancer incidence rates over the past several decades is in part thought to reflect increased diagnostic scrutiny,” they write. “However, incidence rates for both cancer types increased for late-stage and large tumors, suggesting the role of underlying risk factors such as increases in intermittent recreational sun exposures for melanoma and radiation and other unrecognized carcinogens for thyroid cancer.”
There are “many reasons for optimism about the potential for research to accelerate the development of highly effective treatments,” the report stresses. Yet, it adds, “important challenges remain in the access and delivery of cancer care to enable all populations to benefit from treatment advances.”
Some of the new cancer drugs cost $10,000 per month and are not affordable even by most insured patients because of the high out-of-pocket expenses, which are about 20% of the drug’s cost for Medicare-insured patients). The high cost of cancer treatment dubbed “financial toxicity” has been associated with reduced spending on groceries and clothing, skipped medications and physician appointments to save money, bankruptcy, and mortality. It has been suggested that if measures are not taken to contain the escalating trend in treatment costs, cancer care in the United States could become less affordable and could impede the very goal of the Affordable Care Act, which is to make high-quality health care accessible to all.
Public health efforts aimed at cancer prevention must continue — and intensify — the report says, noting that “a large percentage of the reduction in cancer death rates since 1990 has come from preventive measures rather than treatment advances.” Reduction in tobacco use, for example, is responsible for a full 40 percent of the decline in cancer deaths among men from 1991 to 2003.
Even now, tobacco use accounts for 30 percent of cancer deaths in the U.S. “Devoting increased resources and enacting laws and regulations to strengthen tobacco control policies at both state and federal levels — such as tobacco product pricing strategies, plain packaging, statewide comprehensive smoke-free laws, and reducing nicotine content in tobacco products to nonaddictive levels — could greatly reduce morbidity and mortality from smoking-related cancers and other smoking-related diseases,” the report says.
Obesity is another major risk factor for cancer that requires more aggressive and effective preventive measures, according to the report. It notes that half of all new endometrial cancers in the U.S. and about a quarter of all new cancers of the pancreas and kidney are estimated to be related to obesity, which has reached epidemic proportions in this country.
“Overall cancer death rates continue to decrease in the United States, reflecting improvements in prevention, early detection, and treatment,” the report concludes. “However, progress in reducing mortality and improving survival is limited for several cancers. This requires renewed commitment to redouble our efforts to discover new strategies for prevention, early detection, and treatment and to apply proven interventions broadly and equitably.”