New test cuts frequency of cervical cancer checks

Cervical cancer is among top diseases affecting women globally. According to the World Health Organisation (WHO), about 90 per cent of deaths caused by the disease occur in low and middle-income countries such as Kenya.

Screening tests are recommended for preventing the disease as well as detecting it early, when it can be effectively treated.

The most commonly used test in Kenya is the Pap smear. It enables doctors to detect lesions or abnormal cells in the cervix that can be treated before they turn cancerous.

Kenya is yet to come up with screening guidelines. But most countries recommend that women have their first cervical cancer test at the age of 21. Subsequent ones should take place every three years until the age of about 70 years. Even though screening tests save lives, they can be a source of anxiety for women due to the uncertainty of what the results might reveal.

To address this challenge, women can now benefit from a more accurate cervical cancer screening tool known as the Human Papilloma Virus (HPV) DNA test that does not require frequent screening appointments.

Unlike the Pap smear test that detects abnormal cells caused by the HPV, which is responsible for cervical cancer, the DNA test is able to detect the virus long before it can attack cells and make them abnormal.

A new study published in the Lancet Oncology Journal shows that due to its enhanced accuracy, the HPV DNA test reduces the frequency of screenings women should undergo in life.

The findings showed that women undergoing the test could stop cervical cancer screening at 55 years, if they test negative, as they are predicted to be at low risk of the disease thereafter.

The cessation age of the new test is 20 years earlier than the 75 years limit for the Pap smear test, based on the study that was funded by the Canadian Institutes of Health Research.

Talia Malagon, lead author of the study from McGill University in Canada, noted that the study does not suggest that all screening should stop at age 55, since benefits of continued testing depend on the type of screening used.

“For countries that still use the Pap smear, screening at older ages should further reduce the risk of cervical cancer. However, our results suggest that for countries that use HPV testing as part of their screening, it might be possible to stop screening earlier than we are currently doing, provided women have a negative HPV test.”

HPV DNA tests can detect about 96 per cent of high-grade precancerous lesions as opposed to only 55 per cent in Pap smear tests. This has led to its wide adoption in developed countries. Depending on the country guidelines, women between the ages of 30 to 70 who use the HPV DNA test for regular screening are required to repeat the process every five years as opposed to three years for the Pap smear test. The HPV DNA test can also help with diagnosis when results of Pap smear tests are unclear. This enables doctors to determine — with certainty — the presence or absence of cervical cancer.

According to the researchers, the increasing availability of HPV DNA testing means that it might replace pap smears in many countries.

“But due to the higher cost of HPV testing, higher income countries may be more likely to switch.”

In Kenya, the test was introduced in 2015 but due to cost implications it is still a preserve of the few that can afford it.

Recent statistics released by the International Agency for Research on Cancer in GLOBOCAN 2018 indicate that cervical cancer is the second most prevalent type of cancer in Kenya after its breast variety.

Nevertheless, cervical cancer causes more deaths (12 per cent) than breast cancer in (nine per cent).

"We can prevent the deaths by increasing awareness so women can embrace regular screening for cervical cancer," said Nelly Mugo, a gynaecologist and principal research scientist at the Kenya Medical Research Institute who has done a lot of research on cervical cancer.

Dr Mugo noted that the new HPV vaccine, introduced recently in Kenya, would go a long way in preventing future cervical cancer cases.

The vaccine offers protection against certain HPV types that are responsible for a majority of cervical cancer cases.

For it to be effective, it should be administered to women or girls before they have their first sexual intercourse.

Symptoms of the disease include vaginal bleeding after intercourse, bleeding between periods or after menopause or a watery bloody vaginal discharge that may be heavy or accompanied by a foul odour. Sometimes, those affected may experience pelvic pain or pain after intercourse.