Thousands of Canadians failed to undergo proactive cancer screening or diagnosis of possible cancers last year because of the pandemic, leading some doctors and advocates to fear a future surge in advanced tumors and deaths.
Data obtained by the National Post from two provinces and a report issued by a third show that proactive screening of patients without symptoms, and diagnosis of those suspected of having cancer plummeted in the first months of the coronavirus crisis.
Prostate cancer saw a particularly dramatic change, with 60 per cent fewer biopsies performed in Ontario between last March and August.
The Quebec Health Ministry estimates that over 4,000 people who normally would have been diagnosed with a malignancy during the first COVID-19 wave went undiagnosed.
It has absolutely had an impact. I’ve seen it with my own eyes. It’s extremely stressful
Experts blame both restrictions imposed by the health-care system itself, and patients afraid to visit doctors or the hospital when problems arise.
The number of tests has climbed back to normal levels recently, but there were still hundreds of thousands fewer mammograms, pap smears and colorectal cancer screens conducted on Canadians in 2020 than the year before.
That happened on top of a delay in hundreds of thousands of elective operations, which one prominent surgeon says has almost certainly allowed some cancers to get worse.
“I do believe that patients with cancer in Canada … are being rendered fatal, terminal or incurable, as a result of what’s happened,” said Dr. Neil Fleshner, chair of urology at the University of Toronto. “It has absolutely had an impact. I’ve seen it with my own eyes. It’s extremely stressful.”
While the missed screening may have less short-term impact than delayed surgeries, he said he seems to be encountering more patients with advanced, harder-to-treat disease.
Amid talk of triaging COVID-19 patients to assess who gets priority for limited critical-care resources, Fleshner said triaging of a sort has already occurred in the health care system. Cancer and other non-coronavirus patients have borne the brunt of that prioritizing, the physician said, though he said he supports the efforts to tackle the pandemic.
Based on the Quebec report about the pandemic’s first wave, Eva Villalba worries that over the last year more than 8,000 Quebecers have gone undiagnosed with cancer.
“Where this gets us is another pandemic,” said the executive director of the Quebec Cancer Coalition. “When we do catch these people, when we do screen them and get them through diagnosis, it won’t be early any more, it will be more advanced cases of cancer.”
But not everyone is convinced the consequences of the interruptions will be dire. One prominent skeptic of mass cancer screening programs says they detect so few serious malignancies, the coronavirus is likely to have minimal if any impact.
Only about.5 per cent of screening mammograms finds a tumour of any size.
Where this gets us is another pandemic
The pandemic “gives us a really interesting opportunity to evaluate (screening),” said Dr. Steven Narod, a University of Toronto breast-cancer expert. “I can pretty much promise you there will be no difference.”
Meanwhile, the system in parts of the country is seeing more disruption. Ontario just announced it was scaling back elective surgeries again, after huge numbers have already been delayed.
Since the pandemic began, the province has carried out 215,000 fewer cancer and other operations – not including heart or transplant surgeries – than during the same period a year ago, said Ontario Health Monday.
The pandemic has also affected both cancer screening and diagnosis. Screening programs like regular mammograms for women over a certain age are designed to catch malignancy at an early stage. Diagnosis through biopsy or other means occurs as a result of a patient’s screening results or suspicious symptoms.
Resections – removal of tissue – and biopsies to diagnose cancer dropped in Ontario by about 20 per cent between March and August, with prostate biopsies seeing the steepest decline at 60 per cent, according to figures Ontario Health provided to the Post.
Despite some catch-up later in the year, there were still 15 per cent fewer resections and five per cent fewer biopsies overall in 2020 than before the pandemic. But the testing numbers have increased above the 2019 level this year, the agency adds.
Ontario ordered routine cancer screening paused in March 2020, and the impact was striking.
By the end of the year, the system had done about 360,000 fewer pap smears for cervical cancer, conducted 220,000 fewer mammograms and processed 300,000 fewer colon-cancer tests.
British Columbia’s Provincial Health Services Authority provided less extensive data, but said the province saw a 20-per-cent decrease in new cancer diagnoses in the first part of the pandemic.
Diagnoses are now climbing back up to pre-COVID-19 levels, the agency says. The number of screening mammograms B.C. did this February was about the same as in February 2019.
Quebec’s Health Ministry issued a report in January detailing the pandemic’s impact on cancer care. Based on the reduced number of biopsy and other pathology reports, it estimated 4,119 new cancers went undiagnosed just between March and August of 2020 that would have been found earlier.
Some of the potential impact of the lost screening will be rectified through catching up, and many of the missed tumours would be slow-growing, said Dr. Joseph Ragaz, a University of British Columbia medical oncologist and breast-cancer expert.
But he said a study he and colleagues have just completed – yet to be published – underscores that mammogram screening does significantly reduce the death toll from breast cancer, especially in women 60 and older.
“Clearly, it’s something that may have consequences,” said Ragaz about the pandemic-related cutbacks. “What we really see is that the screening leads to earlier diagnosis, and it will also lead to earlier management of breast cancer.”