Adapting cervical dysplasia screening, treatment and prevention approaches to low resource settings.

Cervical cancer is a common disorder worldwide. Screening and treatment paradigms in highly developed countries have dramatically decreased disease prevalence and the implementation of preventive vaccination against high risk human papillomavirus (HPV) subtypes should decrease prevalence even further. Promising advances are also being made toward the development of a therapeutic vaccine for cervical neoplasia. Underresourced countries suffer from an inability to implement many of the approaches to prevention and diagnosis that have proved successful in countries with adequate resources. Several protocols are presently being developed that are low cost and require minimal training and infrastructure that may allow low-resource areas to begin to improve the early diagnosis of low and moderate grade cervical neoplasia. These protocols should support efforts at early treatment to prevent progression to cancer. Simultaneous expansion of prophylactic and possibly therapeutic vaccine availability is essential in the worldwide fight against this prevalent but largely preventable disease.

Human papillomavirus vaccines: current issues & future.

Cervical cancer is the leading cause of cancer mortality among women in worldwide. Some 99 per cent of cervical cancer cases are linked to genital infection with human papillomaviruses (HPVs) comprised of approximately 15 oncogenic genital HPV types. Most HPV infections resolve spontaneously. But, the remainder persist and may then progress to cervical cancer in some women. In high-resource countries, the best way to prevent cervical cancer is to implement organised gynaecological screening programs with appropriate treatment of the detected pre-cancerous lesions. However, in developing countries, this method is not practicable because of cost and complexity of proper screening. Vaccines against HPV infections hold promise to reduce incidence of cervical cancer cost-effectively. Two Prophylactic HPV vaccines have been thus far developed: Gardasil, a quadrivalent vaccine targeting HPV-6, -11, -16 and -18) and Cervarix, a bivalent vaccine which targets HPV-16 and -18. Both vaccines contain L1 virus-like particles (VLPs) derived from HPV-16 and -18 which are most frequently associated with cervical cancer. The L1-VLP vaccines are HPV type-specific and therefore can effectively prevent infection of a HPV type in question alone. Therefore, the L1-VLP vaccines are hoped to be multivalent for 15 oncogenic HPV types, which comes at a price. Otherwise, costly cytologic screening for cervical cancer is still necessary. The current HPV vaccines thus may not be ultimate strategy and study on new HPV vaccines is needed. Broad-spectrum prophylactic vaccines against all oncogenic HPV types and therapeutic vaccines for clearance of HPV-related cervical lesion are being developed.