Public health policies and treatment advances have made a difference.
In 1971, President Richard Nixon declared a war on cancer. Many oncologists and patients now reject the bellicose analogy but coming up to the 50th anniversary of Nixon’s statement, the progress that has been made against the second leading killer of Americans is notable.
Because of a combination of public health policies, medical advances, and social reforms, the overall, age-adjusted cancer death rate has been falling since 1991 when it peaked at 215 cancer deaths per 100,000 people. The death rate from cancer declined by 2.2% from 2016 to 2017, the largest single-year drop ever, according to the American Cancer Society’s Cancer Facts & Figures 2020 report.
Earlier diagnosis, more precise treatment, and reduced exposure to known carcinogens — principally cigarettes — have had a favorable effect on five-year survival rates, which now stand at 70% for Whites and 64% among Blacks, as well as on mortality rates.
Lung, colorectal, breast, and prostate cancer are among the most common types of cancer, so declines in their death rates account for much of the drop in the overall death rates. Here are mortality rate trends for those cancers as reported in cancer society’s 2020 report:
The cancer society also noted a steep decline in melanoma deaths that it attributes to treatment advances. “The accelerated drops in lung cancer mortality as well as in melanoma that we’re seeing are likely due at least in part to advances in cancer treatment over the past decade, such as immunotherapy,” said William Cance, M.D., the chief medical and scientific officer for the American Cancer Society, in a statement. “They are a profound reminder of how rapidly this area of research is expanding, and now leading to real hope for cancer patients.”
It is important to understand the journey of cancer research and treatment that led to the 25-year decline in deaths, but also to set new goals to ensure treatment is more personalized and equitable in years to come.
“There are certain cancers that have very poor prognoses and high fatality rates. Some of these cancers could benefit from making preventive healthcare and better lifestyles become accessible to all,” notes Smita Bhatia, M.D., M.P.H., an investigator on the St. Baldrick’s Foundation–SU2C Pediatric Cancer Dream Team and director of the Institute for Cancer Outcomes and Survivorship at the University of Alabama, Birmingham. Others, such as pancreatic cancer, she says, require ongoing scientific discovery, and equal access of the scientific discovery to all, in order for death rates to continue to decline.
Maybe one of the more under-appreciated facts about cancer in the United States is huge growth in the number of Americans who have had cancer who are still living: cancer survivors. In an opinion article published in the New England Journal of Medicine in September, Richard Schilsky, M.D., chief medical officer and executive vice president of the American Society of Clinical Oncology (ASCO), and his coauthors noted that there were 3 million cancer survivors in the United States in 1970. Now there are almost 17 million. The country has a larger population, and the cancer incidence—the number of new cases diagnosed each year—has tripled from just over 600,000 in 1970 to a projected 1.8 million cases this year, Schilsky and his colleagues noted. Earlier detection because of screening and treatment advances factor into survivorship. In 1970, the five-year survival rate was 49%. Now it is about 70%.
“It was a very different landscape both in understanding risk factors for cancer, understanding cancer biology, and having a wide array of cancer-specific treatments,” Schilsky said in podcast that accompanied the article.
In the NEJM article, Schilsky and his colleagues credit the 1971 National Cancer Act billed by Nixon as launching a war on cancer as catalyzing the progress in cancer treatment over the past 50 years. They credit the law with increasing funding for research and creating the network of comprehensive cancer centers, which, in turn, led to new treatment strategies (including palliative care), a better understanding of risk factors, and a national network of clinical trials.
In the podcast, Schilsky talked about risk factors “coming into much clearer focus” and efforts to mitigate those risks, including prophylactic breast surgery for women with the highly penetrant BRCA gene mutations, sunscreen to prevent skin cancer, programs to encourage Americans to quit smoking, and vaccination against the human papillomavirus to protect against cervical and anal cancer.
The role of screening
All of this occurred against the backdrop of recognizing that early detection of cancer is associated with better outcomes and that has led to the widespread implementation of cancer screening strategies, said Schilsky, who mentioned screening for cervical, colorectal, breast, and lung cancer specifically.
But cancer screening is controversial. Otis Brawley, M.D., a professor at Johns Hopkins University in Baltimore and a member of the Managed Healthcare Executive® editorial advisory board, has been outspoken about what he sees as overscreening that leads to false positives, overtesting, and overtreatment. “Yes, we are still overscreening, but it is not as bad as it once was, especially in prostate cancer,” Brawley said in a recent interview with the MHE editors.
A 2018 article posted on the National Cancer Institute’s website titled “Crunching Numbers: What Cancer Screening Statistics Really Tell Us” goes through some of the explanations and arguments for how screening may skew cancer mortality statistics, including lead-time and length bias. Moreover, any relative risk reduction seen in a cancer screening program that covers the general population is likely to translate into reductions in absolute risk that are quite small for the simple reason that for a general population the risk of developing cancer is small.
Although overall cancer mortality figures are encouraging, the disaggregated numbers paint a different picture. Survival rates are lower for Black patients (62%) than for White patients (68%) for every type of major cancer except for kidney and pancreatic cancer, for which they are roughly the same, according to Cancer Facts & Figures 2020.
The American Association for Cancer Research (AACR) published a 156-page report about disparities in September. “In recent years, some strides have been made in combating cancer health disparities, as illustrated by narrowing of racial and ethnic disparities in the overall cancer incidence and death rates,” the report notes. “However, progress has come too slowly, and the cost of all health disparities, including cancer and COVID-19 health disparities—in terms of premature deaths, lost productivity, and the impact on communities—remains monumental and must be addressed.” AACR recommendations for closing the disparity gap include increasing funding for efforts to close the gap and enrolling diverse populations in clinical trials.
Donna Marbury is a freelance writer in Columbus, Ohio.