Vaccination against human papillomavirus

We disagree with many of Abby Lippman and colleagues' arguments against HPV vaccination.1 The quantity and quality of the scientific evidence in support of HPV vaccines and new technologies for cervical cancer screening, such as HPV testing, are just as good as, if not better than, those anchoring other strategies for cancer prevention. As with most new vaccines, cost is a concern. With time, competition and economies of scale make vaccination policies more affordable. A paradigm change in cervical cancer screening using HPV-testing technology is likely to occur in synergy with vaccination and will help to improve cost- effectiveness.2 There are lessons to be learned, but adjustments in policies can be made as the new science emerges.

Seemingly cautious arguments that we do not know enough about HPV vaccination of girls and women are irrelevant and untenable. The vaccines have been thoroughly tested in young women aged 15–25 years at risk of HPV exposure and proven to be safe and efficacious; immunobridging studies indicate that the immune response in adolescents is stronger than in young and old adults; and to be of maximal benefit, vaccination programs must focus on pre-exposure prophylaxis. The argument about herd immunity is not yet one that we can use. Eventually, phase IV trials may lead to policy revisions, and vaccination of boys and men could become a complementary prevention strategy.

The argument that cervical cancer will not develop in most women infected with oncogenic HPVs ignores basic cancer epidemiology. Most smokers will not develop lung cancer, yet we consider smoking cessation the foremost cancer prevention paradigm. More importantly, lung cancer can develop in people who have never smoked, but an infection with an oncogenic HPV type is a necessary precursor for cervical cancer. Incidentally, safe sex is practically an oxymoron in the prevention of HPV infection; condom use is not protective.3

Finally, we disagree with the argument that there is no Canadian cervical cancer epidemic to justify urgency. Cervical cancer rates have declined in Canada, but the enormous costs and morbidity resulting from screening and managing precursor lesions are seldom appreciated. By analogy, Canadian childhood cancer mortality (180 deaths of children aged 0–19 years in 20074)has declined, but not fast enough. Would we oppose a federal policy that could prevent 70% of childhood cancers? The 400 Canadian women who die of cervical cancer every year4 suffer unbearable pain and loss of function and form. Their dignity slips away as the disease progresses and treatment fails. Pelvic exenteration, a heroic act by gynecologic oncologists to rescue patients with locally advanced disease, is among the most gruesome and complex of all surgical procedures and is psychologically devastating. No economic analysis can assign a proper value to a procedure that causes so much suffering, or to an initiative that would allow patients to avoid it.

Eppur si muove.