Report: U.S. Cancer Rates Have Fallen for at Least 25 Years
Although that is good news, cancer is the second-most common cause of death in the U.S., with more than 1.7 million new cancer cases each year and more than 600,000 cancer deaths. The report notes that one of the biggest factors in decreased cancer rates are lower tobacco smoking rates. Improvements in early detection and treatment are also a factor.
Unfortunately, obesity-related cancer deaths are increasing, and deaths caused by prostate cancer have leveled out—they were dropping.
Cancer death rates increased in the U.S. until the early 1990s, the report notes. It has dropped ever since, decreasing 27 percent between 1991 and 2016. As mentioned above, this is related to smoking. Lung cancer rates have dropped by almost 50 percent among men since 1991. Siegel notes that it is a delayed effect from a drop in smoking that began in the 1960s.
Prostate cancer is the second leading cause of cancer death in men. For twenty years prostate cancer death rates dropped. From 2013 to 2016, however, those rates flattened. Researchers and physicians wonder if that stagnation is related to a 2011 decision by the U.S. Preventive Services Task Force to stop recommending routine prostate-specific antigen (PSA) blood testing for men.
Cancer deaths related to obesity include thyroid, pancreatic and uterine cancer, as well as liver cancer. Liver cancer deaths increased since the 1970s but were associated with hepatitis C (HCV) infections. HCV infection is decreasing, largely due to the effectiveness of various HCV drugs like Gilead Sciences’ Harvoni and Sovaldi.
However, with that drop in HCV-related cancers, obesity is linked to about a third of liver cancer deaths, a bigger factor than hepatitis. Siegel is concerned that because risk factors do not necessarily show up for decades, these new links to obesity and cancer “may just be … the tip of the iceberg in terms of the effect of the obesity epidemic on cancer.”
It’s important to note that the biopharmaceutical industry has played an important role in decreasing cancer rates. The entire field of immuno-oncology, which has really come to fruition in the last few years, has revolutionized the treatment for certain types of cancers, and drugs are increasingly targeting specific patient populations.
Just a few examples of 2018 approvals include Array BioPharma’s June 2018 approval for Braftovi and Mektovi for unresectable or metastatic melanoma with a BRAFV600E or BRAFV600k mutation; Regeneron Pharmaceuticals’ Libtayo for cutaneous squamous cell carcinoma, approved in September 2018; Pfizer’s Talzenna in October 2018 for deleterious germline BRCA-mutated HER2-negative locally advanced or metastatic breast cancer; Pfizer’s Daurismo in November 2018 for newly-diagnosed acute myeloid leukemia in adults 75 years or older; Janssen’s Erleada for prostate cancer in February 2018; AstraZeneca’s Lumoxiti for relapsed or refractory hairy cell leukemia, and many others.
From November 2016 through October 2017, the U.S. Food and Drug Administration (FDA) approved 18 new cancer therapies and 13 new uses of cancer therapies. And 2017 was an historic year, when the first T-cell and gene therapy for cancer was approved. The American Society of Clinical Oncology notes, “Research results on other immunotherapies and targeted therapies released in 2017 have changed the treatment paradigms for lung, prostate, and bladder cancer.”
And although this latest report is good news, more than 14 million people worldwide will be diagnosed with cancer, with almost 9 million death a year, or 22,000 cancer deaths daily. And it’s expected to increase, hitting 21 million cancer patients worldwide and 13 million annual deaths by 2030.
One of the things the new American Cancer Society report discusses are disparities in cancer deaths related to income, race and gender. Darrell Gray, deputy director of Ohio State University’s Center for Cancer Health Equity, noted, “We’ve known for some time that race is a surrogate” for other factors, such as poverty and access to healthcare, as well as paying for care.
The ASCO report states, “Significant cancer health disparities continue to exist in certain populations. Race, ethnicity, socioeconomic status, and geography all affect patient health outcomes, and racial and ethnic minorities and individuals of lower socioeconomic status experience worse cancer outcomes.”
Age is also a significant factor. According to ASCO, more than 60 percent of cancer diagnoses in the U.S. are in people 65 years or older. Yet older adults are underrepresented in clinical trials. In November 2017, ASCO and the FDA held a workshop to evaluate ASCO’s recommendations to improve the evidence base for treating older adults, and ASCO continues to encourage federal agencies and the cancer research community to increase enrollment of older adults in clinical trials.
Siegel concludes the ACS report, “Although the racial gap in cancer mortality is slowly narrowing, socioeconomic inequalities are widening, with residents of the poorest counties experiencing an increasingly disproportionate burden of the most preventable cancer. These counties are low-hanging fruit for locally focused cancer control efforts, including increased access to basic health care and interventions for smoking cessation, healthy living, and cancer screening programs. A broader application of existing cancer control knowledge with an emphasis on disadvantaged groups would undoubtedly accelerate progress against cancer.”