January 13, 2021
For the second year in a row, mortality from cancer has fallen in the United States, driven largely by reductions in the incidence of, and death from, non-small cell lung cancer (NSCLC) in men and women, according to a new report from the American Cancer Society.
The study was published online January 12 in CA: A Cancer Journal for Clinicians.
"Mortality rates are a better indicator of progress against cancer than incidence or survival because they are less affected by biases resulting from changes in detection practices," comment the authors, led by Rebecca Siegel, MPH, American Cancer Society, Atlanta, Georgia.
"The overall drop of 31% as of 2018 [since the early 1990s] translates to an estimated 3,188,500 fewer cancer deaths (2,170,700 in men and 1,017,800 in women) than what would have occurred if mortality rates had remained at their peak," researchers add.
Importantly, lung cancer accounted for 46% of the total decline in cancer mortality in the past 5 years, with a record, single-year drop of 2.4% between 2017 and 2018.
The recent and rapid reductions in lung cancer mortality reflect better treatments for NSCLC, the authors suggest. For example, survival rates at 2 years have increased from 34% for patients diagnosed with NSCLC between 2009 and 2010 to 42% for those diagnosed during 2015 and 2016 -- an absolute gain of 5% to 6% in survival odds for every stage of diagnosis.
On a more somber note, the authors warn that COVID-19 is predicted to have a negative impact on both the diagnosis and outcomes of patients diagnosed with cancer in the near future, as previously reported by Medscape Medical News.
"We anticipate that disruptions in access to cancer care in 2020 will lead to downstream increases in advanced stage diagnoses that may impede progress in reducing cancer mortality rates in the years to come," Siegel said in a statement.
New Cancer Cases
The report provides an estimated number of new cancer cases and deaths in 2021 in the US (nationally and state-by-state) based on the most current population-based data for cancer incidence through 2017 and for mortality through 2018. "An estimated 608,570 Americans will die from cancer in 2021, corresponding to more than 1600 deaths per day," Siegel and colleagues report.
The greatest number of deaths are predicted to be from the most common cancers: lung, prostate and colorectal cancer in men and lung, breast and colorectal cancer in women, they add. However, the mortality rates for all three cancers are continuing to fall.
As of 2018, the death rate from lung cancer had dropped by 54% among males and by 30% among females over the past few decades, investigators note.
Mortality from female breast cancer has also dropped by 41% since 1989; by 52% for prostate cancer since 1993; and by 53% to 59% for colorectal cancer for men (since 1980) and women (since 1969), respectively.
In contrast, the pace of the annual decline in lung cancer mortality doubled among men from 3.1% between 2009 and 2013 to 5.5% between 2014 and 2018, and from 1.8% to 4.4% among women during the same time intervals.
Increase in Incidence at Common Sites
Despite the steady progress in mortality for most cancers, "rates continue to increase for some common sites," Siegel and colleagues report.
For example, death rates from uterine corpus cancer have accelerated from the late 1990s at twice the pace of the increase in its incidence. Death rates have also increased for cancers of the oral cavity and pharynx -- although in this cancer, increases in mortality parallel an increase in its incidence.
"Pancreatic cancer death rates [in turn] continued to increase slowly in men ... but remained stable in women, despite incidence [rates] rising by about 1% per year in both sexes," the authors observe.
Meanwhile, the incidence of cervical cancer, although declining for decades overall, is increasing for patients who present with more distant-stage disease as well as cervical adenocarcinoma, both of which are often undetected by cytology.
"These findings underscore the need for more targeted efforts to increase both HPV vaccination among all individuals aged [26 and younger] and primary HPV testing or HPV/cytology co-testing every 5 years among women beginning at age 25," the authors emphasize.
On a more positive note, the long-term increase in mortality from liver cancer has recently slowed among women and has stabilized among men, they add.
Once again, disparities in both cancer occurrence and outcomes varied considerably between racial and ethnic groups. For example, cancer is the leading cause of death in people who are Hispanic, Asian American, and Alaska Native. Survival rates at 5 years for almost all cancers are still higher for White patients than Black patients, although the disparity in cancer mortality between Black persons and White persons has declined to 13% from a peak of 33% in 1993.
Geographic disparities in cancer mortality rates also still prevail; the rates are largest for preventable cancers such as lung and cervical cancer, for which mortality varies by as much as fivefold across states.
And although cancer remains the second most common cause of death among children, death rates from cancer have continuously declined over time among both children and adolescents, largely the result of dramatic declines in death rates from leukemia in both age groups.
The study authors have disclosed no relevant financial relationships.