The Pap test being replaced

Quebec plans to use the more accurate HPV test, which could be offered by self-sampling

Louise Leduc
The Press

A small revolution in sight in cervical cancer screening in Quebec.

Within a few months, it is hoped, the Pap test will be replaced in the first line by the HPV test.

Considered more precise, the HPV test can be done in the clinic, but also at home – yes, with a swab! –, a possibility that is being studied.

Last week, in an interview with The Press on various women’s health topics, the D^r Lionel Carmant, Minister Delegate for Health and Social Services, had let go. “The Pap test is outdated. »

This declaration is in line with an opinion of the National Institute of Excellence in Health and Social Services (INESSS), which, in January, published an opinion recommending that we stop giving first intention to the cytological Pap test (named after its inventor, the Greek doctor Georgios Papanicolaou, for the record) to prefer the HPV test.

Almost all cases of cervical cancer are caused by human papillomaviruses (HPV) transmitted sexually or by direct contact with infected mucous membranes.

Over time, the virus can cause abnormal cells that can lead to cervical cancer.

The Pap test consists of an analysis of cells taken from the cervix in order to detect abnormal cells. The HPV test, on the other hand, allows the detection of the virus from a genital swab.

The Pap test would continue to be used, but only later, when the HPV test would have shown the presence of the virus.

INESSS recommends administering the HPV test to women from age 25 to age 65.

One of the advantages of the HPV test is that it might only be done every five years (rather than every two or three years for the Pap test).

Australia and the Netherlands have already implemented the HPV test as the primary test for screening for cervical cancer, indicates INESSS.

” It is enormous ! »

In terms of screening, the HPV test, “it’s huge! “says the D^D Josianne Paré, obstetrician-gynecologist at the Fleurimont Hospital of the Sherbrooke University Hospital Center and spokesperson for the file on behalf of the Association of Obstetricians and Gynecologists of Quebec.

An important first step was taken in 2008 when the vaccine against the human papilloma virus began to be offered to all girls in the fourth year of primary school, then, from 2016, to boys of the same age.

Since the 1970s, indicates the D^D Paré, the Pap tests have made it possible to “reduce the incidence of cancer of the cervix”, a downward trend which, with vaccines, should be accentuated.

INESSS (under the pen of Caroline Turcotte, lead author of the opinion) notes that the expected decrease in the incidence of HPV infections and cervical lesions following vaccination – good news, of course – could however “lead to poorer screening performance by the Pap test, in particular by affecting the positive predictive value of this test”.

The HPV test therefore now appears “as a superior tool”, continues the D^D Ready. Because it is more sensitive, but also because it is less heavy.

Self-test possible

Minister Lionel Carmant indicated that the entire file of cervical cancer screening had been entrusted to the national director of mother and child health (although screening obviously affects all women and not not just mothers).

Many questions remain. One of them: will this test always be done during a clinic visit or could it be done at home?

According to INESSS, “self-sampling should be offered to under-screened people. This includes all people who do not participate in screening according to the guidelines”.

Eventually, “depending on the evolution of knowledge”, self-sampling could also be offered to the general population”, we can also read in the opinion of INESSS.

But with COVID-19, it has been clear that not everyone is a small swab champion, they say at the D^D Ready.

A priori, she replies, it’s not very complicated and if the sample was badly taken, in the laboratory, it would be known immediately. No risk of being wrong, therefore.

But given that so many women are not followed by a doctor, if the test was done at home, who would do the follow-up?

This is among the questions that future protocols will have to answer, says the D^D Ready.

A (small) reservation

In the scientific literature, however, it is noted that the HPV test has a lower specificity than that of the Pap test. (Specificity measures the ability of a test to give a negative result. It’s the true negative rate.) What about?

“With the HPV test, we don’t focus on the cells, but on the presence of the virus, recalls the gynecologist. It is possible that we have the virus without having abnormal cells, that the virus, therefore, has not yet caused any damage. »

But anyway, continues the D^D Paré, the HPV test is 40% more sensitive and only 2% less “specific” than the Pap test, a difference which is not significant in his opinion.

The latest developments in screening inspire him. Because despite the great strides that have been made in the prevention of cervical cancer, “young women aged 20 or 30 still do not know that there is screening”, worries the D^D Ready.

Eventually, she continues, cervical cancer screening should be part of a program as structured as that for breast cancer whereby every Quebec woman, at age 50, receives an invitation from the government to take a mammography.

Finally, it should be noted that cancer of the cervix is ​​only one of several other gynecological cancers to follow.