Studies estimate that the COVID-19 pandemic can cause death among cancer patients, with predictions in a rise of US cancer deaths over the next decade owing to screening deficits, and others blaming cancer surgery delays in Ontario to poorer survival rates. 

To accommodate critically ill COVID-19 patients, several healthcare facilities canceled or delayed appointments for other indications, including cancer. Before COVID-19 vaccines were available, patients with nonemergent conditions were advised to stay home rather than risk infection in hospitals. 

Median 18% drop in colorectal cancer screening

In a study published in Cancer, a team led by Northwestern University researchers conducted a national quality-improvement (QI) study on the return to cancer screening among 748 accredited US cancer programs. Pre-pandemic and pandemic monthly screening test volumes (MTVs) to identified screening gaps were used. 

Most facilities reported gaps in monthly screenings for colorectal cancer (104 of 129 [80.6%]), cervical cancer (20/29 [69.0%]), breast cancer (241/436 [55.3%]), and lung cancer (98/220 [44.6%]).

The median relative changes in MTVs were -17.7% for colorectal cancer, -6.8% for cervical cancer, -1.6% for breast cancer, and 1.2% for lung cancer. No geographic differences were seen.

These findings prompted participating cancer programs to start 814 QI projects to break down barriers to cancer screening, including screening resources. The screening rates of these projects are still being evaluated, but all facilities have set target goals that could be 57,141 for breast cancer, 6,079 for colorectal cancer, 4,280 for cervical cancer, and 1,744 for lung cancer.

"Cancer screening is still in need of urgent attention, and the screening resources made available online may help facilities to close critical gaps and address screenings missed in 2020," the researchers wrote.

10-year survival could fall up to 0.9%

University of Toronto researchers built a microsimulation model using real-world population data on cancer care in Ontario from 2019 and 2020 to test the effect of COVID-19-related surgery delays on survival. 

The study published in the Canadian Medical Association Journal (CMAJ) estimated cancer surgery wait times over the first 6 months of the pandemic by simulating a slowdown in operating room capacity (60% operating room resources in month 1, 70% in month 2, and 85% in months 3 to 6), compared with simulated pre-pandemic conditions with 100% resources.

The model population consisted of 22,799 patients awaiting cancer surgery before the pandemic and 20,177 new referrals. The average wait time to surgery before the pandemic was 25 days, compared with 32 days afterward. As a result, 0.01 to 0.07 life-years were lost per cancer patient, translating to 843 life-years lost among cancer patients.

With a 60% reduction in surgical resources for cancer patients in the first six months of the pandemic, incremental increases in wait time of 10 to 21 days over pre-pandemic wait times translated to 0.1 to 0.11 life-years lost per patient and reductions in 10-year survival of 0.3 to 1.6 percentage points across cancer types.