The Pap test that has been used for decades as the standard in cervical cancer screening for Canadian women should be replaced by a test that detects high-risk types of human papillomavirus (HPV), a new study says.
The virus is associated with the vast majority of cervical cancers.
Whether they receive a Pap test or HPV test, the experience for patients is the same in their doctors’ or nurse practitioners’ offices. Women have the same physical exam whereby their cervix is swabbed for cells. The difference happens when that sample is sent to the lab for analysis.
The clinical trial, conducted in B.C. and published in the Journal of the American Medical Association (JAMA), randomly divided about 19,000 women into two groups. The control group had the traditional Pap test for their initial screening, while the test group had primary HPV screening — a test that looked for more than a dozen specific types of HPV most likely to cause precancerous lesions in the cervix.
The HPV test found almost 60 per cent more precancers — or abnormal cells that could potentially become cancerous — during the initial screening than the Pap test, said study co-author Dr. Dirk van Niekerk, a pathologist who is also the medical leader of the cervical cancer screening program at the B.C. Cancer Agency.
That kind of early detection is the hallmark of cervical cancer prevention, because health-care providers can take action to treat precancerous cells before they become cancer. Depending on the “grade,” or how far advanced they are, they may simply require monitoring (because in younger patients, the cells sometimes repair themselves on their own)
Alternatively, they can be removed with laser treatment or with an electrical wire loop — a procedure known as “LEEP.”
“The pre-cancerous stage is essentially 100 per cent curable,” van Niekerk said. “They usually take up to 10 years to progress to cancers, but the point is if you don’t