Targeting the human papillomavirus for prevention of cervical cancer
Different types of human papillomavirus (HPV) vary in the extent they cause precursor lesions (CIN) and cancer. There are limited long-term efficacy data on HPV testing in primary screening Among 72 cervical cancers in Mozambique, HPV 16 and 18 were the most frequent HPV types (69% of cases). Comparing 108 cervical cancers cases and 517 matched controls nested within a population-based cohort in Taiwan, HPV 16 seropositivity implied a 6-fold increased cancer risk. In a cohort of 5696 women in Sweden, HPV types 16, 31 and 33 conveyed the highest risks for future high-grade CIN (CIN 2+), attributing to 33.1%, 18.3% and 7.7% of CIN 2+ cases, respectively. In a pooled analysis of seven European longitudinal studies of HPV-based cervical screening, the cumulative incidence rate of CIN grade 3 or worse (CIN 3+) was higher after 3 years among women with normal cytology than among women with a negative HPV test after 6 years. Finally, in a randomized cervical cancer screening trial in Sweden, adding testing for HPV persistence resulted in a 51% (95% CI: 13-102) increase of CIN 2+ at prevalent screening, which was followed by a reduction of 42% (95% CI: 4-76) of CIN 2+ at incident screening. In conclusion, HPV-based cervical cancer screening protects against future CIN 2+, and the long-term protective effect should enable extended screening intervals to 6 years. Albeit HPV 16 is the most important carcinogenic HPV type all over the world, different ?high-risk? HPV types convey distinctly different risks for CIN 2+, which should be considered in design of screening tests and vaccines.
Microbiology in the Medical Area, bakteriologi, virologi, Mikrobiologi, mycology, virology, bacteriology, prevention, Microbiology, CIN, vaccine, cervical intraepithelial neoplasia, screening, cervical cancer, Human Papillomavirus, HPV, mykologi, Public health, epidemiology, Folkhälsa, epidemiologi
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