Over the past 25 years, there has been a 27 percent drop in the overall U.S. cancer death rate, which translates into about 2.6 million fewer cancer deaths between 1991 and 2016. These statistics are contained in a new report from the American Cancer Society (ACS), “Cancer statistics, 2019,” which was published early online in CA: A Cancer Journal for Clinicians (2019; doi:10.3322/caac.21551). The ACS also released a consumer version, “Cancer Facts & Figures 2019.”
“We have made stunning progress against cancer and the 27 percent decline in the overall death rate over the last 25 years is a testament to that success,” commented ASCO President Monica M. Bertagnolli, MD, FACS, FASCO, in a statement on the report. But the rising incidence of deaths due to obesity-related cancers is of concern, as are data showing continuing inequities in cancer care, said Bertagnolli, Chief of the Division of Surgical Oncology at Brigham and Women's Hospital and Professor of Surgery at Harvard Medical School.
Indeed, news from the new ACS report is not all good. The report, which contains many statistical tables, cites statistics showing that death rates from some cancers are rising, not dropping. It also cites troubling data showing inequities among Americans that affect U.S. cancer mortality. While racial disparities in cancer mortality are shrinking, differences by socioeconomic status (SES) are growing. The report, which analyzed cancer mortality rates by county-level poverty, states that by one estimate about one-third (34%) of cancer deaths in Americans aged 25-74 could likely be averted by eliminating the SES divide. “Inferior survival among those with low SES is predominately driven by a later stage of disease at diagnosis and less-aggressive treatment,” the report states.
“We are seeing the racial gap in cancer deaths is narrowing between blacks and whites—but it still exists and needs to be recognized for what it is: an inequality in care and outcomes,” said J. Leonard Lichtenfeld, MD, MACP, Deputy Chief Medical Officer for the national office of the ACS, in a commentary on the new report. “At the same time, another significant inequality is getting worse, and that's related to socioeconomic status, which includes income, education, insurance status, as well as living in rural, underserved counties throughout the country.”
In 2016, 22 percent of all U.S. deaths were from cancer, making it the second-leading cause of death after heart disease for both men and women. In many states, cancer is the leading cause of death, as well as in Hispanic and Asian Americans and people under age 80.
The lifetime probability of being diagnosed with invasive cancer is slightly higher for men (39.3%) than for women (37.7%), which the report states may reflect differences in environmental exposures, endogenous hormones, and “probably complex interactions between these influences.” Sex differences in immune function and response may also play a role.
The new ACS report notes that the steady overall decline in U.S. cancer deaths is attributable primarily to a sustained drop in smoking and to advances in early detection and treatment, especially for the four major cancers: lung, breast, prostate, and colorectal.
The new report, written by ACS staffers Rebecca L. Siegel, MPH, Kimberly D. Miller, MPH, and Ahmedin Jemal, DVM, PhD, shows that the death rate for lung cancer dropped by 48 percent for men from 1990 to 2016 and by 23 percent for women from 2002 to 2016. The female breast cancer death rate dropped by 40 percent from 1989 to 2016, while the prostate cancer death rate dropped by 51 percent from 1993 to 2016. Mortality from colorectal cancer dropped 53 percent from 1970 to 2016.
In contrast to dropping death rates for the four major cancers, death rates rose from 2012 through 2016 for liver, pancreatic (men only), and endometrial cancers. Death rates also rose for brain and other nervous system cancers, soft tissue (including heart), and sites within the oral cavity and pharynx association with HPV.
The ACS report shows that from 2006 to 2015 the U.S. cancer incidence rate overall was stable in women and declined by about 2 percent in men. In men, this drop reflects accelerated declines in the past 5 years of about 3 percent per year for lung and colorectal cancers, as well as a drop of 7 percent per year for prostate cancer. Declines in cancer incidence for women have continued for lung cancer, the report shows, but have slowed in recent years for colorectal cancer, while incidence rates for other common cancers are increasing or stable (e.g., an increase of 0.4% for breast cancer).
The 5-year survival rate for all cancers combined diagnosed during 2008 through 2014 was 67 percent for whites and 62 percent for blacks, which shows that racial disparities in cancer care are narrowing, according to the ACS report. But in contrast, socioeconomic disparities are widening, with the most notable gaps for the most preventable cancers. For example, the report shows that the most dramatic socioeconomic difference in death rates occurred for colorectal cancer and reflects a shift over time; death rates for men in the poorest counties were about 20 percent lower than in affluent counties in the early 1970s, but now are 35 percent higher.
The report's authors say this shift is due to changes in diet and smoking patterns that put people at increased risk for colorectal cancer, as well as slower dissemination of screening and treatment advances among populations in lower socioeconomic groups.
“In contemporary times, the prevalence of behaviors that increase cancer incidence and mortality are vastly higher among residents of the poorest counties, including double the prevalence of smoking and obesity compared to residents of the wealthiest counties,” the authors state.
Ironically, some states are home to both the wealthiest and poorest counties, suggesting statewide opportunities for improvement, suggest the ACS report's authors. “A broader application of existing cancer control knowledge with an emphasis on disadvantaged groups would undoubtedly accelerate progress against cancer.”
Lichtenfeld noted that in the poorest U.S. counties death rates from cervical cancer are two times higher than in other parts of the country, a statistic which “speaks volumes” about the need for early detection, treatment, and HPV vaccination for all who are eligible in the U.S. He said the fact that SES differences are especially striking in cancers for which effective early detection and treatment exist shows that the country needs to do more to reduce cancer disparities between affluent and disadvantaged Americans through increased access.
“The findings in this report reflect the sad truth that where a patient lives often dictates their chances of surviving cancer for a wide range of reasons,” Bertagnolli said. “For example, ASCO's 2018 National Cancer Opinion Survey found that rural patients typically spend 50 minutes traveling one way to see their cancer doctor compared to 30 minutes for non-rural patients. This extra hardship is compounded in poorer counties where something as simple as a full gas tank can make the difference in a person's ability to get the care they need.”
As previously reported in Oncology Times, data from a recent patient advocacy summit sponsored by the National Comprehensive Cancer Network in Washington, D.C. showed that the inability to afford a $100 tank of gas for a truck puts even one cancer treatment out of reach for many Native Americans living on rural reservations far from cancer treatment centers. At that summit, Shonta Chambers, MSW, Executive Vice President-Health Equity and Community Engagement for the Patient Advocate Foundation, stressed that providing high-quality care to underserved patients today must address the patient's social, financial, geographic, and economic issues, regardless of cancer type.
Bertagnolli also cited another ASCO concern about SES disparities in cancer care: unequal participation in clinical trials. “This report also highlights our long-standing concerns about the underrepresentation of individuals from lower socioeconomic populations in cancer clinical trials and the access to treatment advances these trials may provide. We must work to ensure every patient has access to cancer care that reflects their individual needs as well as the opportunity to participate in research and contribute to progress,” she noted.
Bertagnolli said ASCO commends ACS for “annually monitoring cancer incidence, mortality, and trends in the United States,” and stated that ASCO intends to “continue our efforts towards furthering the progress we have made in treating cancer and eliminating disparities in care.”
Peggy Eastman is a contributing writer.