Published February 4, 2022 in medicalnewstoday.com
By Kimberly Drake
Many people have a cancer diagnosis or know someone living with cancer, which might make it seem as though the incidence of this disease is on the rise. In this Special Feature, Medical News Today investigates the latest surveillance data and speaks with experts to find out if cancer rates are really increasing.
Cancer impacts people of all ethnicities, sexual identities, and economic backgrounds. Although cancer prevention and treatment strategies have improved over the years, cancer diagnoses appear to be rising.
But have cancer rates really increased? And if so, what factors are playing a role? To try and answer these questions, Medical News Today investigated the latest data and statistics on cancer prevalence and mortality rates.
We also spoke with two experts about cancer rates and the impact COVID-19 may have had on cancer prevention, diagnosis, and treatment.
How prevalent is cancer currently?
According to one study published in JAMA OncologyTrusted Source, and based on data from the Global Burden of Diseases, Injuries, and Risk Factors Study, 2019Trusted Source, 18.7 million people worldwide received a cancer diagnosis in 2010, and the total deaths from cancer numbered 8.29 million.
Fast forward to 2019, and those numbers had increased significantly, with 23.6 million people receiving a new cancer diagnosis and records documenting 10 million cancer deaths.
The scientists who conducted the research also found that among 22 groups of injuries and diseases studied, cancer was the second leading cause of death, years of life lost, and disability-adjusted life years.
The World Health Organization (WHO)Trusted Source indicates that the most common types of cancers diagnosed in 2020 were:
- breast cancer (2.26 million diagnoses)
- lung cancer (2.21 million diagnoses)
- colon and rectal cancer (1.93 million diagnoses)
- prostate cancer (1.41 million diagnoses)
- nonmelanoma skin cancer (1.20 million diagnoses)
- stomach cancer (1.09 million diagnoses)
Furthermore, lung cancer caused 1.8 million deaths, closely followed by:
- colorectal cancer (935,000 deaths)
- liver cancer (830,000 deaths)
- stomach cancer (769,000 deaths)
- breast cancer (685,000 deaths)
StatisticsTrusted Source indicate that males experience a higher cancer mortality rate than females. Additionally, the death rate from cancer is highest among Black males and lowest among Asian and Pacific Islander females.
Yet despite these statistics, the American Cancer SocietyTrusted Source suggests that, in the United States, the overall cancer mortality rate has been steadily decreasing over the last 28 years. For example, the organization indicates the death rate from cancer fell 32%Trusted Source between 1991 and 2019when considering data from males and females.
Factors that may play a role in this decrease include:
- a reduction in the number of people who smoke, as smoking is a leading cause of lung cancer
- the addition of chemotherapy treatment after surgery for breast and colon cancer
- the use of combination therapy for many cancers
- the advancement of prevention and early detection strategies for some cancer types
In addition, the organization reports an increase in the 3-year survival rate for people living with lung cancer. For example, in 2004, 21 in 100 people with a diagnosis of lung cancer were living 3 years after diagnosis. In 2018, that number rose to 31 in 100 people.
Progress with diagnosing lung cancer in the localized stage and improvements in surgical techniques and treatment medications may play a role in the improved survival rate.
What forms of cancer are on the rise?
Although the overall mortality rate from cancer may be decreasing, certain types of cancer are on the rise. For example, according to Cancer Statistics, 2022Trusted Source, published in the American Cancer Society’s journal, CA: A Cancer Journal for Clinicians, data from 2014 to 2018 indicated a 0.5% annual increase for female breast cancer. At the same time, the incidence of prostate cancer remained stable.
Between 2015 and 2050, the Centers for Disease Control and Prevention (CDC)Trusted Source expects new cancer diagnoses in the U.S. to stabilize in females and decrease in males.
However, the CDC projects that colorectal, prostate, and female breast cancers will rise, and cancer diagnoses in older adults will increase due to an aging population.
In addition, research indicates that from 1973 to 2015, certain subtypes of cancer — specifically carcinoma of the kidney — have risen in adolescents and young adults in the U.S., with an overall cancer rate increase of 29.6%Trusted Source in this age group.
What is causing an increase in cancer rates?
Although we are making progress with some types of cancer, the National Cancer InstituteTrusted Source suggests that the incidence of other cancers may rise due to an increase in some risk factors.
These include the fact that people are living longer — as a person’s cancer risk tends to increaseTrusted Source as they advance in age — and the fact that many people also have obesity.
ReportsTrusted Source suggest that people with obesity may have an increased risk for certain types of cancer. Worldwide, 650 millionTrusted Source adults had obesity in 2016.
In addition, continued difficulties with accessing quality healthcare due to socioeconomic challenges or racial bias may contribute to an increase in cancer rates.
For example, according to a WHO reportTrusted Source, 90% of countries in the high income group have comprehensive treatment available. In comparison, less than 15% of countries in the low income group have access to quality treatments.
Dr. Susan Pandya, head of cancer metabolism global development oncology and immuno-oncology at Servier Pharmaceuticals, told MNT:
“While death rates are decreasing, there has been an increase in diagnoses, with an expected increase of almost 50% by 2050. With the growing population — including the elderly population — and the utilization of advanced imaging diagnostics, which detect earlier stages of cancer and/or more indolent forms of cancer, rates could continue to climb.”
Has the COVID-19 pandemic impacted cancer rates?
It may be many years before surveillance data accurately depict COVID-19’s impact on cancer rates. Still, reduced access to healthcare facilities because of pandemic-related closures and reluctance to attend medical appointments because of fear of exposure to SARS-CoV-2 may have negatively impacted cancer prevention, diagnosis, and treatment.
Dr. Michael Zinner, the CEO and executive medical director at Miami Cancer Institute, told MNT:
“A report in the Journal of Clinical Oncology shared that, at the height of the pandemic in April 2020, colon cancer screenings by colonoscopy were down 75%. Modeled experiences show that at 10 years (2030), there are up to potentially 4,000 more deaths from colon cancer. Essentially, the warning is that these delayed screenings due to [COVID-19] are a ticking time bomb with a 10-year fuse.”
He added: “I worry that screening will also be impacted — mammograms, colonoscopies, CT scans for lung cancer, or even visits to the gynecologist. For example, we’ve gone to virtual visits for many of our medical oncologists, almost all of our genetics, almost all of our cancer patient support services, but we really can’t do that for radiation therapy or for surgical preop cases. We’ve really been hit.”
Dr. Zinner reported that, as of early- to mid-January, 310 out of 1,800 employees at his place of work — about 17% — were absent due to COVID-19. This included 7 out of 12 radiation therapists.
“Unfortunately, it’s the same in [New York] and Boston. In Boston, they have administrators being used as transport, pushing patients to X-ray and radiation therapy. It’s been dramatic, but hopefully, we’re on the recovery side of Omicron. [B]ut I don’t know for sure,” he said.
Dr. Zinner emphasized that people with cancer were receiving appropriate treatment despite these challenges.
“Regarding elective procedures like colonoscopies, we may have to postpone their screening because either the patient or the staff have [COVID-19]. Canceling your cancer care is never a good idea. Postponing cancer care is what we have to do.”
— Dr. Michael Zinner
Dr. Pandya said that “the COVID-19 pandemic has, without a doubt, impacted cancer diagnoses. This is likely due to the various challenges that patients and providers faced in accessing and providing care during unprecedented times.”
“It is important to note [that] cancer incidence and mortality data lag 2–4 years behind the current year due to the time it takes to collect, compile, quality check, analyze and interpret the data,” Dr. Pandya noted. “Therefore, we do not have a full picture just yet on how the pandemic has affected these statistics.”
She also reported that cancer testing and screening rates are currently still lower than they were pre-pandemic.
“While we must fight COVID-19, we can’t lose sight that cancer is a leading cause of death in the U.S., second to heart disease,” Dr. Pandya emphasized.
‘Today, we understand more’
Although an aging population and increased incidence of known cancer risk factors may contribute to an overall increase in cancer rates, other factors may play a role. These may include better diagnostic techniques, more open exchange of healthcare information, and improved awareness.
Dr. Pandya explained that “today, we understand more about risk factors for certain cancers, such as environmental exposures and healthy living habits, leading to more awareness about cancer incidence and prevention.”
Still, despite the apparent increase in cancer rates, data suggest that the mortality rate from cancer is decreasing. This trend may result from earlier diagnosis and improved treatment strategies, translating into a hopeful future for people living with cancer.