Pandemic-related disruptions have resulted in decreases in both diagnostic testing for cancer and new diagnoses based on data from the national veterans healthcare system, according to a study results published in the journal Cancer.

While it is known that the COVID-19 pandemic has led to delays in cancer treatment, its impact on new diagnoses is less clear. Brajesh Lal, MD, of the University of Maryland in Baltimore, and colleagues assessed differences in the number of diagnostic procedures and new diagnoses for bladder cancer, colorectal cancer, lung cancer and prostate cancer before and during the pandemic.

For this study, the researchers examined all diagnostic and screening tests and new cases diagnosed between 2016 and 2020 using data from the Veterans Health Administration. They evaluated trends in these numbers from January 2018 through December 2020. They established the baseline period as 2018 to 2019 and compared figures for those years to numbers from 2020.

Between 2018 and 2020, the researchers identified 4.1 million cancer-related health care encounters, 3.9 million diagnostic and screening procedures and 251,647 new cancer diagnoses.

Overall, cancer-related encounters fell sharply in April and May 2020 compared with the same months in 2018 and 2019, but they rebounded to near the previous levels by that summer. In April 2020, encounters related to bladder, prostate, colorectal and lung cancers fell by 27%, 26%, 19% and 10%, respectively, compared with April 2018 and 2019.

Diagnostic and screening procedures declined even more steeply. In April 2020, colonoscopies, prostate biopsies, cystoscopies (bladder exams), chest CT scans, cystoscopies, colonoscopies and fecal occult blood tests for colon cancer decreased by 93%, 80%, 74%, 64% and 54%, respectively. And unlike overall encounters, diagnostic procedures did not rebound to baseline levels and remained lower throughout 2020. During 2020, the number of colonoscopies was 45% below the annual pre-pandemic number, and prostate biopsies, cystoscopies, fecal blood tests and chest CT scans were 29%, 21%, 13% and 12% lower, respectively.

New cancer diagnoses fell between March and June 2020. Although new diagnoses began to rise again in June, they did not return to pre-pandemic levels. On the other hand, the researchers observed no rebound above baseline levels to make up for lost time. Comparing 2020 to previous years, the number of new diagnoses fell by 23% for prostate cancer, 20% for colorectal cancer, 18% for bladder cancer and 13% for lung cancer.

“The authors identified substantial reductions in procedures used to diagnose cancer and subsequent reductions in new diagnoses of cancer across the United States because of the COVID-19 pandemic,” they wrote. “These reductions were different across states and worsened even as pandemic-related curbs improved.”

Click here to read the study in Cancer.

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