During the early months of the COVID-19 pandemic in 2020, elective medical procedures, including screenings for breast cancer, were curtailed to prioritize urgent medical needs and reduce the risk of spreading the coronavirus in health-care settings. A study showed that, as of May 2020, preventive screenings for breast and cervical cancer dropped by 94%. Breast cancer treatment protocols were also changed, resulting in delays in treatment and reductions in chemotherapy administration.

A recent study by Alagoz et al published in the Journal of the National Cancer Institute examined the impact of the disruption in breast cancer control. Due to the short-term declines in screening and delays in diagnosis and treatments during the first 6 months of the pandemic, the study authors predict that there will be 2,487 additional breast cancer deaths between 2020 and 2030. That figure would likely double if the pandemic’s effects on delays in screening, symptomatic diagnosis, and chemotherapy administration were extended for 12 months, according to the study’s findings.

Study Methodology

The researchers used three established breast cancer simulation models from the National Cancer Institute’s Cancer Intervention and Surveillance Modeling Network to predict the effect of COVID-19–related interruptions on mammography screening, delays in symptomatic cancer diagnosis, and reductions in chemotherapy use among women with early-stage disease from March to September 2020. Sensitivity analyses were performed to determine the effect of key model parameters, including the duration of the pandemic impact.

Each model estimated the effect of COVID-19 disruptions on breast cancer deaths among all women aged 30 to 84 years between 2020 and 2030 in the United States.

Results

The researchers found that by 2030, the models projected 950 (model range = 860–1,297) cumulative excess breast cancer deaths related to reduced screening; 1,314 (model range = 266–1,325) associated with delayed diagnosis of symptomatic cases and 151 (model range = 146–207) associated with reduced chemotherapy use in women with hormone receptor–positive, early-stage cancer. Jointly, 2,487 (model range = 1,713–2,575) excess breast cancer deaths were estimated, representing a 0.52% (model range = 0.36%–0.56%) cumulative increase expected by 2030 in the absence of the pandemic’s disruptions.

Sensitivity analyses indicated that the breast cancer mortality impact would be approximately double if the modeled pandemic effects on screening, symptomatic diagnosis, and chemotherapy extended for 12 months.

“Initial pandemic-related disruptions in breast cancer care will have a small long-term cumulative impact on breast cancer mortality. Continued efforts to ensure prompt return to screening and minimize delays in evaluation of symptomatic women can largely mitigate the effects of the initial pandemic-associated disruptions,” concluded the study authors.

Clinical Significance

“There were many reports on the short-term impact of COVID-19 on breast cancer control activities,” said lead study author Oguzhan Alagoz, PhD, Professor in the College of Engineering, Population Health Sciences at the University of Wisconsin-Madison School of Medicine and Public Health, in a statement. “We found that the rapid adaptations of health-care facilities to devise strategies to resume breast cancer screening, diagnosis, and treatment services within a 6-month period greatly mitigated the potential impact on breast cancer mortality. Facilities should prioritize screening women who missed their routine mammography exam during the pandemic to reduce the impact of [the] pandemic on mortality.”

Disclosure: For full disclosures of the study authors, visit academic.oup.com/jnci.