Now researchers are studying the impact, looking to see how many cancers were missed and whether tumours found since then are more advanced.

Studies suggest that fewer cancers were diagnosed last year, likely because of the drop in screening. About 75 cancer organisations recently urged a return to pre-pandemic screening levels as soon as safely possible.

‘Get the damn mammogram’: breast cancer awareness month

But tumours take years to develop, and some reports suggest that a few months’ delay in screening for certain types of cancer may not have been as bad as feared. For example, researchers in the Netherlands found that a lapse in that country’s mammography programme did not lead to more cancers being found at a late stage after screening resumed.

The pandemic also bred some creative solutions, such as wider use of tests that can be done at home. In Philadelphia, a large church partnered with local doctors and used its drive-through flu-shot programme to also pass out stool tests for colon cancer screening.

“We’re not afraid to try anything as it relates to health and wellness,” said Reverend Leroy Miles of Enon Tabernacle Baptist Church. “The women were encouraging men to get the screening, saying, ‘I got my mammogram.’ And I’m saying, ‘ma’am, you have a colon too’.”

‘Don’t trade your health for wealth’: breast cancer survivor

Screening tests differ in their risks and benefits, and health experts have long debated who should get which ones and how often. The pandemic lapse may serve as a “natural experiment” to see their value in modern times versus what’s known from studies done long ago.

Any difference in deaths may not be seen for years, and early detection is only one factor in survival. Treatment also matters, and it was hurt by pandemic delays too.

Based on what’s known about breast cancer deaths from past years in the US, about 10 per cent “could have been prevented if women were getting routine screening”, but 20 per cent to 25 per cent could have been prevented with appropriate treatment, said Dr Otis Brawley, a Johns Hopkins University professor and former chief medical officer of the American Cancer Society.

“That’s not to say screening is not important, but many people think that cancer screening saves more lives than it actually does,” Brawley said.

A short-term delay may not hurt mortality much if screening resumes quickly, as it needs to do, he said.

Some reassuring news came at a recent American Association for Cancer Research conference from Sabine Siesling of the Netherlands Comprehensive Cancer Organisation. That country offers women ages 50 to 74 a mammogram every two years, but stopped in mid-March 2020 because of Covid-19. After it resumed in late summer, results “did not show any shift” to more advanced tumours, she reported.

Researchers from Massachusetts General and Brigham and Women’s Hospital analysed their screening tests for lung, cervical, colon, prostate and breast cancer. Screening dropped dramatically between March and June, but the proportion of tests that found cancer or a precancer was higher than usual, suggesting that those who did get screened were at higher risk.

When screening returned to near normal from June to September, the number of potentially “missed” cancers was lower than expected.

Why a Hong Kong family crowdfunded father’s cancer fight

Miles, who has drawn more than 1,000 church members to other health events, called the University of Pennsylvania and said: “We know how to get people to come if you’re willing and able to set something up.”

Dr Carmen Guerra had a US federal government grant to increase screening in racially diverse communities and realised that home tests could help. Studies show these tests, which look for blood in stool, help save lives. People put a tiny stool sample in a tube and mail it to a lab or, in this case, use a drop box at the church. If blood is found, the next step is colonoscopy.

Doctors passed out kits in the car park during a drive-through flu-shot event in October. Church members had to watch a video about colon cancer in advance and register to ensure they qualified for screening.

So far, 154 kits have been returned. Stacy Hill was among the 13 who tested positive. The 48-year-old Philadelphia woman had just lost her job and health insurance. Her colonoscopy revealed two growths that, like Abraham’s, were caught before they turned cancerous.

“I was shocked,” Hill said. “I’m a proactive-type person so I was glad to know.”

The doctors also helped her enrol in Medicaid, “so now I have medical insurance” and can continue getting cancer screenings, she said.

The church hopes to offer the home tests again during blood pressure and diabetes screening events this spring.