Diagnosis of new cancer cases declined during the pandemic and has not recovered to expected levels, according to a study published in the March issue of the Journal of the National Comprehensive Cancer Network .

Antoine Eskander, M.D., from the University of Toronto, and colleagues assessed the impact of the pandemic on weekly reported cancer incidence. Analysis included 358,487 adults diagnosed with cancer in Ontario, Canada, from Sept. 25, 2016, to Sept. 26, 2020.

The researchers found that at the start of the pandemic, there was an immediate 34.3 percent decline in the estimated mean cancer incidence volume (relative rate, 0.66), followed by a 1 percent increase in cancer incidence volume in each subsequent week (relative rate, 1.009). Both screening and nonscreening cancers followed similar trends. Melanoma and cervical, endocrine, and prostate cancers had the largest immediate declines. A weekly decline in incidence during the COVID-19 period continued for hepatobiliary and lung cancers. Early in the pandemic (March 15 to Sept. 26, 2020), 12,601 fewer people were diagnosed with cancer, with an estimated weekly backlog of 450.

"Our data demonstrates that many cancers have gone undetected due to the disruptions in the health care system in response to the COVID-19 pandemic," Eskander said in a statement. "This is concerning because a delay in diagnosis for cancer is associated with a lower chance of cure."

Two authors disclosed financial ties to the pharmaceutical industry.

Abstract/Full Text