Medically reviewed by Susan Kerrigan, MD and Marianne Madsen
The COVID-19 pandemic upended lives and daily routines. It affected many people’s social, mental, and economic health, and the full effects of the pandemic may only be felt in years to come. But, for cancer patients, the consequences of COVID restrictions might be felt a lot sooner.
Cancer and Screenings
Cancer is the second leading cause of death in the US (after heart disease). According to the CDC, just under 600,000 Americans died from cancer in 2019. To combat this, many health organizations and professionals recommend regular cancer screenings. These screenings can help discover some forms of cancer early, before they have grown and spread and become harder to treat. One study showed that breast cancer deaths were reduced by around 20% as a result of screenings.
Postponement of Screenings
At the start of the coronavirus pandemic, many cancer organizations and agencies, including the American Society of Breast Surgeons and the American College of Radiology, recommended postponing screenings. This was to help protect staff and patients and help stop the spread of COVID. This resulted in a sharp decline in the number of cancer screenings. One study published in May 2020 showed cancer screenings had dropped by between 86% and 94% in 2020 compared to the three previous years. The research was updated two months later to show a rise in screenings. However, screenings were still around 30% lower than pre-COVID levels.
Cancer Death Rate
The American Cancer Society (ACS) estimates that around 608,570 Americans will die from cancer in 2021. At the moment, there hasn’t been sufficient data published to suggest that any additional deaths might be caused as a direct result of COVID. However, the ACS believes that the long-term impact of delayed cancer screenings will see an increase in late-stage diagnoses where the probability of death is much higher.
Estimated Increase in Mortality from Cancer due to Screening Delays
The notion that delayed screenings would lead to higher mortality was backed up by a journal article written by Norman Sharpless, director of the National Cancer Institute (NCI), in June 2020. Based on NCI data modeling, he estimated that the pandemic would cause an additional 1% increase in breast and colorectal cancer deaths by 2030. This is equivalent to 10,000 extra deaths as a result of delays in screenings during COVID.
Sharpless also highlights the effect that COVID has had on clinical research and trials. He argues that research has moved toward examining the effects of the virus on cancer patients and away from broader cancer research. With labs being temporarily closed and clinical trials suspended, progress on developing new, more effective therapies has been delayed. According to Sharpless, pausing research and trials could cause slowdowns in cancer progress for many years to come.
Restart Strategies
Any discussion of mortality rates should consider what strategies are being put in place for restarting screenings. In a study cited in the British Journal of Cancer, several methods were examined, including restarting without catching up on missed screenings, immediately catching up, and gradually catching up, among others. The findings showed that when screenings were not rescheduled and simply canceled, cancer deaths increased. However, immediate or gradual catching up helped to reduce the increase in mortality rates.
The impact of COVID on cancer deaths can only be assessed once we have sufficient data to compare to previous years. Evaluating how much of that increase may have been caused by delayed or canceled screenings instead of other factors such as delayed treatments might be harder to quantify.
References
- An Update on Cancer Deaths in the United States
- Cancer Screening Overview (PDQ®)–Patient Version – National
- Benefits and Harms of Breast Cancer Screening: A Systematic Review
- ASBrS and ACR Joint Statement on Breast Screening Exams During the COVID-19 Pandemic
- Delayed Cancer Screenings
- Delayed Cancer Screenings—A Second Look
- Cancer Facts and Figures – 2021
- COVID-19 and cancer
- Effects of cancer screening restart strategies after COVID-19 disruption