Vaccination for cervical cancer
Summary
Cervical cancer, one of the most common gynaecological cancers, is the consequence of persistent infection by the human papillomavirus family. This article is an authoritative review on the subject, by Professor Ian Hector Frazer internationally acclaimed for his work on the development of the world’s first cervical cancer vaccine. (Image - © istockphoto.com)
Key Points
- Cancer of the cervix is a consequence of persistent infection of cervical epithelium by the human papillomavirus family.
- Infection with high-risk papillomaviruses is predominantly acquired through sexual intercourse, and occurs in at least 30% of young women and men, generally before the age of 25.
- Cervical cancer prevention to date has relied on screening for the cellular consequences of persisting infection with high risk human papillomavirus, through the Pap smear program.
- Commercial vaccines to prevent infection with high-risk human papillomaviruses have recently become available. Production of these recombinant vaccines is similar to production of the currently available recombinant Hepatitis B vaccines.
- These vaccines have been demonstrated ~95% effective at preventing infection with the HPV types they incorporate, and 100% effective at preventing HPV associated disease.
- The vaccines have proven safe and well tolerated.
- Maximum benefit from delivery of vaccine programs is to younger women before onset of sexual activity, although women already infected with one HPV type will likely benefit from protection against infection with the other HPV types incorporated in the vaccine.
- HPV vaccines currently available have the potential to prevent the ~70% of cervical cancer caused by HPV16 and HPV18 infection, and are therefore an adjunct to, rather than a replacement for, whatever cervical cancer screening programs are currently available.
Declaration of interests: As the inventor of a technology that supports the HPV vaccines currently available, IH Frazer and his university derive royalties from their sale. He also consults in the HPV vaccine field for Merck, and for CSL.
Cancer of the human cervix is a consequence of persistent infection of cervical epithelium by one of a limited number of members of the human papillomavirus family. This family of over 200 related viruses includes some which cause genital and body warts, with no apparent malignant potential, and many virus types which produce no apparent disease. However, a group of about 10 human papillomaviruses, particularly exemplified by HPV16, are termed high-risk viruses because persisting infection can lead to epithelial cancer of the anogenital epithelium, and contribute to about 20% of head and neck cancers and a small percentage of skin cancers.1 Infection with high-risk papillomaviruses is predominantly acquired through sexual intercourse, and occurs in at least 30% of young women and men, generally before the age of 25. Infection is common, largely because the lesion of acute infection is asymptomatic and persists for an average of a least a year. In consequence, HPV associated cancers are also common, contributing 10% of the total global cancer burden. Cervical cancer, the most common HPV associated cancer, kills 0.25 million women worldwide each year, and is one of the two most common causes of cancer death in women in most resource poor and developing countries