Researchers have documented a substantial decline in cancer and precancer diagnoses at the Northeast's largest health-care system (Massachusetts General Brigham) during the first peak of the COVID-19 pandemic due to a drop in the number of cancer screening tests performed. These findings were published by Ziad Bakouny, MD, MSc, and colleagues as a research letter in JAMA Oncology.

The findings, which confirm concerns that COVID-related restrictions may have delayed the detection and treatment of many cancers, were moderated somewhat by data showing that cancer screenings and diagnoses at the health-care system largely rebounded to prepandemic levels in the months following the initial peak. The study provides added impetus for people who missed or postponed a cancer screening test early in the COVID-19 pandemic to contact their health-care provider to discuss the potential need to reschedule one, the study authors said.

Ziad Bakouny, MD, MSc

“It's widely thought that fewer people were screened for cancer and precancerous lesions during the first surge of the pandemic, because of limitations on nonurgent medical procedures, restrictions on patient volume, patients' concerns about the spread of the virus, and the need for social distancing,” said Dr. Bakouny, of Dana-Farber Cancer Institute. “For this study, we wanted to document the extent of this decline, and its impact on cancer diagnoses, at a major U.S. health-care system.”

Study Methods

The investigators drew on a registry of patient data at Massachusetts General Brigham, a system of hospitals, community health centers, and physician practices in Massachusetts. They tracked how many people underwent cancer screening tests—mammograms, colonoscopies, Papanicolaou (Pap) tests, prostate-specific antigen (PSA) tests, and low-dose computed tomography (CT) scans—and how many were diagnosed with cancer. The data covered four 3-month periods: March 2 to June 2, 2020, the first peak of the pandemic; the previous 3 months; the subsequent 3 months; and the same 3 months in 2019.

Decline in Screening, Diagnoses

The statistics revealed a significant decline in cancer screening during the peak period. A total of 15,453 patients underwent screening exams in the March to June time frame, compared to 64,269 in the previous 3 months and 60,344 in the same 3 months of 2019. However, screening levels largely recovered in the 3-month post-peak period, to 51,944.

The decrease in screening tests was accompanied by decreases in diagnoses of the cancers detected by those tests. The researchers calculated that had the same number of people been screened during the peak period as in the previous 3 months, approximately 1,438 additional cancers and precancerous growths would have been diagnosed.

The falloff in diagnoses, though temporary, is a source of concern because cancers detected at an early stage are often easier to treat than those that aren't discovered until they've had time to grow and spread, pointed out Dr. Bakouny.

“It's reassuring, though, to see that in the 3-month post-peak period, the number of screening tests and diagnoses resulting from those tests returned to a near-normal level,” he added.

The researchers also found that the percentage of screening tests resulting in a cancer or precancer diagnosis was higher during the height of the pandemic than at other times. This may be because, at a time of limited screening availability, physicians recommended screening primarily for patients at highest risk for cancer.

“This investigation is especially timely, given that we are currently dealing with a second, and potentially worse, wave of the pandemic,” said co–senior author Quoc-Dien Trinh, MD, of Brigham and Women's Hospital. “We have learned to leverage a redesigned patient flow, increased use of telehealth, and made other accommodations to allow our patients to continue receiving standard-of-care cancer screening and diagnosis in the safest possible environment.”

While the study focused on a single, large health-care system in one part of the country, emerging data suggest its findings have relevance for other regions as well, concluded Dr. Bakouny.

Disclosure: For full disclosures of the study authors, visit jamanetwork.com.