HPV is the most common sexually transmitted disease and is one of the main causes of cervical cancer, killing more than 250,000 women every year world-wide.
HPV infections are common, affecting 70-80% of the female population throughout lifetime. Although spontaneous regression occurs in 90% of the cases, a significant number of women with persistent infections will develop cervical cancer. HPV infection is sexually transmitted with the highest prevalence in young women around 20 years old. The progression to cervical cancer takes 10-15 years, and Pap smear screening programs are commonly introduced to find women with cervical cell changes and follow them closely until regression or treatment if progression to precancerous lesions (dysplasia) is detected. HPV testing is increasingly used in follow-up of patients and may soon be introduced in primary screening programs.
Surgery has undesirable side effects
From screening programs in the developed part of the world, cervical Pap smears are obtained regularly to check for the presence of cervical dysplasia. Cervical dysplasia is mainly treated by local surgical procedures (conisation) including loop electrosurgical excision procedure (LEEP), loop excision of transformation zone (LETZ), laser and cold knife in addition to cryosurgery. Unfortunately, conisation also removes normal cervical tissue that may lead to bleeding, infection, stenosis, infertility and preterm delivery in later pregnancies. Tissue-preserving procedures like Cevira would therefore be attractive for treatment of cervical dysplasia.
No treatment available for HPV
HPV tests are increasingly available and are used together with colposcopy and cervical cell sampling (cytology) to address persistent and aggressive HPV infections. HPV tests are increasingly included in public screening programs, but no standard therapeutic treatment is available. HPV infection is also the cause of genital warts. Prophylactic HPV vaccines are available but have only moderate coverage and will not significantly impact the number of patients with cervical dysplasia in the short-term.
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2. Ferenczy A, Franco E. Persistent human papillomavirus infection and cervical neoplasia. The Lancet Oncology 2002;3:11-16.