This photomicrograph shows cancerous cells detected by a Pap test. Canada is phasing out the Pap test for a more accurate HPV detection test that can be performed less often.A. Elizabeth Plott/The Canadian Press
Canada is beginning to phase out the Pap test – a ritual of women’s health care for decades that dramatically reduced deaths from cervical cancer – to make way for a more accurate test that can be performed less often.
Most provincial health-care systems are switching or studying switching to a new test that detects high-risk strains of the human papillomavirus (HPV), the sexually transmitted pathogen that causes nearly all cervical cancers.
“It’s better because it detects accurately,” said Gina Ogilvie, a Tier 1 Canada Research Chair in global control of HPV-related diseases and prevention and a professor at the University of British Columbia. “When you use it, you detect those precancerous lesions earlier and also, when you have a negative HPV test, you have greater confidence in the results.”
Because the new HPV test is more reliable than the old-fashioned Pap, women’s health experts say it can safely be performed every five years instead of every three. It can also be done at home with a swab that women administer themselves and pop in the mail.
In May, Prince Edward Island became the first province to publicly fund HPV testing as its primary means of screening for cervical cancer, but without self-swabbing at home as an option. Quebec and New Brunswick have publicly announced plans to switch, but haven’t yet done so. Other provinces are laying groundwork for the change and running pilot projects, including British Columbia, which hosted a landmark randomized clinical trial that showed HPV testing is superior to the Pap.
Dr. Ogilvie was one of the leaders of HPV FOCAL, a study that divided more than 19,000 healthy B.C. women into two groups: One screened with the HPV test and the other with a Pap test.
The Pap test, named for its Greek creator, George Papanicolaou, involves a doctor or nurse scraping cells from the wall of the cervix and sending them to a lab, where they’re examined under a microscope for abnormalities that could be harbingers of cancer.
The HPV test begins in much the same way – with a swab of the cervix taken by a health-care professional or a person at home – but ends with a different type of lab equipment searching for the DNA of HPV and genotyping it to see if it’s one of the strains likelier to cause cancer.
The HPV FOCAL trial found that cervical pre-cancer was discovered earlier in women who had HPV testing, allowing them to be treated before invasive cervical cancer could develop.
Those results, published in 2018, reinforced earlier research and bolstered the case for replacing the Pap, but didn’t spur overnight change in Canada. In fact, some women’s health experts argue the country’s fractured health system, where each province and territory moves at its own pace, is taking too long to make a switch that several of its peers, including Australia and Britain, have already adopted.
“It’s a wonderful project,” said Diane Francoeur, the chief executive officer of the Society of Obstetricians and Gynaecologists of Canada. “But for now it is slow, slow, slow. Way too slow.”
Others say it is critical that jurisdictions take their time to build the lab infrastructure and public education campaigns necessary for a successful switch to HPV testing – one that won’t provoke the backlash Australia experienced when it transitioned in 2017 to women being screened every five years with the HPV test instead of every two with the Pap.
“The switch is not as easy as it might sound,” said Craig Earle, the chief executive officer of the federally funded Canadian Partnership Against Cancer (CPAC). Besides educating women and doctors about the longer interval between tests, health leaders must figure out how to track results and follow up with patients who don’t have a regular primary-care provider, particularly if at-home HPV tests are widely adopted, Dr. Earle added.
Still, there have been some concrete steps forward. In June, CPAC – which is encouraging the switch to HPV testing as part of a national commitment to eliminate cervical cancer by 2040 – and two Canadian medical specialty societies published the first national guidelines on HPV testing for clinicians. That was a few weeks after PEI implemented its province-wide program with the help of $621,000 from CPAC.
For now, PEI is only offering the HPV test in person, so the experience for women is not much different than getting a traditional Pap, save for the five-year interval between tests, said Krista Cassell, a Charlottetown obstetrician-gynecologist.
PEI is hoping to eventually offer self-sampling, an approach that Dr. Ogilvie in B.C. said her province has already tested and found to be successful in a pilot program that sent at-home testing kits to more than 10,000 women.
Self-sampling has the potential to increase cervical cancer screening rates among women who live in rural and remote communities, those who don’t have a doctor, and those who avoid Pap tests because of past trauma, said Amanda Selk, a gynecologist at Women’s College Hospital in Toronto and the president of the Society of Canadian Colposcopists, one of the groups behind the new guidelines for HPV testing.
Dr. Selk knows that some will prefer to keep being screened for cervical cancer in-person, if only to talk with a doctor about their overall health.
She and others who support phasing out Pap tests say both in-person and at-home HPV tests should be available. “I think we do a disservice to Canadians by not allowing people choices when the technology is there,” Dr. Selk said. “It would be a huge loss to not have self-screening options.”
If at-home HPV-screening reaches more women, and if enough young people get the HPV vaccine, there is hope that Canada can achieve its goal of eliminating cervical cancer by 2040, said Lucy Gilbert, the director of gynecologic oncology at McGill University Health Centre. “And then my grandchildren’s generation won’t be talking about HPV screening.”