Within the next 50 years, cervical cancer could probably be wiped out if countries execute national screening programs based on discovery of the human papilloma virus (HPV). Supposedly it may be the reason for the disease, jointly with vaccination programs against the virus. This has been claimed by a cervical cancer screening expert.
It was mentioned in Berlin by Professor Jack Cuzick in Europe’s largest cancer congress, ECOO 15 – ESMO 34 that while the existing HPV vaccines apparently guard against two cancer-causing strains of the HPV virus, very soon there might be vaccines on hand that may shield against nine types of strains. If vaccination were to be joined with HPV screening, then gradually the cancer may vanish from those countries that had claimed to effectively execute national programs.
“It’s important to say up front that the HPV is responsible for all cervix cancer. If you can eradicate the virus, the cancer will not appear. So the current vaccine holds the promise of eradicating about 70-75% of cervical cancers (caused by HPV types 16 and 18), and there appears to be some additional cross protection amongst types that are closely related to 16 or 18, in particular 31, 45 and a little bit of 33. There are new vaccines being planned that will vaccinate against nine types. If they are successful, there should be no need to screen women that have been vaccinated at all. That’s the long-term future: vaccination and no screening. After about 50 years, we could see cervical cancer disappearing,” commented Professor Cuzick, who is the John Snow Professor of Epidemiology and head of department at the Cancer Research UK Centre for Epidemiology, Mathematics and Statistics, Wolfson Institute of Preventive Medicine.
As the existing HPV vaccine apparently only guards against two of the cancer-causing types, supposedly vaccinated women may still need screening throughout their life.
Professor Cuzick, explained, “Women vaccinated above the age of about 16 will need to be regularly screened for the rest of their life, because the vaccine is not effective in women who have already been exposed to the virus. Even for girls vaccinated before this age with the current vaccine, there will be a need for some screening to protect from cancers caused by HPV types not in the vaccine, so screening is here to stay for the foreseeable future. However, we need to change to screening for HPV rather than the Pap smear test, and then it will be possible for the tests to be conducted at longer intervals.”
The Pap test apparently depends on personal evaluation by people investigating the cells in the smear with a microscope and errors could take place. In contrast, the HPV test is approximately entirely automated, and it may be intended to spot the virus in the smear than depending on visual examination, and so it may have fewer chances to be affected by human error.
Professor Cuzick remarked, “There’s overwhelming evidence that HPV screening is more effective than the Pap smear test, which misses about a third to a half of all high grade lesions. There are now several available commercial HPV tests and most of these tests show a sensitivity (the proportion of true positives correctly identified) in the order of 95% for high grade lesions, whereas cytology is somewhere between 50-70%. So it would really streamline the service because you could test less frequently, and it’s also been shown that the protection lasts longer so that screening every five to seven years is probably appropriate.”
He is of the opinion that the European Union and national governments ought to take the lead in debates on executing screening and vaccination programs.
Professor Cuzick mentioned, “There’s been a lot of concern, particularly with the vaccine, that dissemination of information about HPV has come mainly from the drug companies, and people are, not surprisingly, a little sceptical of pharmaceutical-based education programs. So if the EU was to take this up without pharmaceutical support, I think it would be very appropriate and it would provide a forum that would be extremely legitimate.”
He added, “For younger women we think HPV testing should happen every five years starting at age 25-30; by the time they’re 50, if they’ve been negative, they could probably be screened every eight years. So there’s a lot to be gained, both in terms of better protection and less frequent screening, which will save time and money. If women can go less often and get more protection it makes a lot of sense.”
The price of HPV may go down in the coming months with the number of tests increasing.
It is said to be more accurate and shifting to HPV testing could also save the government’s money in the long run.