Guest blog: Cancers caused by HPV can be eradicated by vaccination25.08.2023
One of the priority projects of the European Union's cancer control program aims to root out cancers caused by the human papilloma virus (HPV) by 2030 in the EU. The EU's goal is vaccination coverage exceeding 90% for girls and a significant increase in vaccination coverage for boys.
The disease burden caused by HPV is high. Approximately 80% of people get an HPV infection at some point in their lives without the vaccine. Although people often recover from the infection, in some it can linger and lead to premalignant growth and, if left untreated, to cancer.
HPV infection can cause several cancers
In addition to cervical cancer, HPV infection causes cancers in the genital area including external female genitals, vagina, penis, and anus. About one third of head and neck cancers are caused by HPV. The prevalence of HPV is highest in oropharyngeal cancers (36–58%). HPV also causes condylomas and papillomas.
Large-scale cervical cancer screenings were introduced in Finland in the 1960s, when the connection of HPV as a cause of cancer was not yet understood. Thanks to the screening program, the number of cervical cancers decreased dramatically. Screening has shifted the focus from cervical cancer to the treatment of its precursors. In Finland, the annual number of treatments for cervical cancer precursors is about 3,000. In addition, there are about 30,000 screen-positive patients being monitored. Despite the screening system, today the number of cervical cancers has increased again, especially among young adults. In 2021, there were 212 new cases.
It is worth noting that screening is only offered for cervical cancer. The results of organised screening for other HPV-related cancers, such as penile, anal or oropharyngeal cancers, are poor.
Vaccination prevents cancer and premalignant growth
The significance of HPV infection as a prerequisite for the development of cervical cancer was presented in the 1970s, and it was not until 1995 that the International Agency for Research on Cancer (IARC) declared the papilloma virus a carcinogen, that is, a cancer-causing agent. The invention was considered significant, as it enabled the development of a vaccine to prevent HPV-related diseases.
The German virologist Harald zur Hausen was awarded the Nobel Prize in Medicine for the research that led to HPV vaccines in 2008. Finns have also actively participated in HPV research. The researcher couple, professors Stina and Kari Syrjänen, are well-respected in the world's HPV science communities, especially as pioneer researchers of HPV in the oral area since the 70s.
The development and introduction of the vaccine has been a success story. It has created hope for eradicating HPV infection and related diseases from the world, diseases which are costly and cause human suffering. Although cervical cancer screening is important, it is already about treating the disease.
Vaccination, on the other hand, is prevention, which targets the cause of cancer and already makes it possible to prevent the precursors and onset of cancer. The first HPV vaccine was approved in 2006. Screening is still needed in addition to the vaccine program, although it could clearly be reduced for vaccinated persons.
More than 500 million HPV vaccine doses administered
There is more research data on the effectiveness and safety of the HPV vaccine than on any other vaccine. More than 500 million doses of HPV vaccines have been administered worldwide. In Finland, all children and young people are equally offered the right to the HPV vaccine. Finland's vaccination programme started in 2013 and boys were added to the programme in 2020.
At the moment, vaccination coverage in Finland is clearly lower than the EU-set goals. There are also notable regional differences in vaccination coverage. However, having a high vaccination coverage for all genders would be crucial in achieving good herd immunity and eradicating diseases caused by HPV.
M.D.Ph.D, specialist in gynecology and obstetrics and psychotherapist. Member of the national HPV network.