Options for triage and implications for colposcopists within European HPV-based cervical screening programmes

The development of human papillomavirus (HPV)-based screening should detect more pre-cancerous changes and so reduce the incidence and mortality from cervical squamous carcinoma and cervical adenocarcinoma. However, many more women are high risk HPV (hrHPV) screen positive compared to cytology-based screening, especially in younger age-women. A variety of tests have become available which may triage into those hrHPV test-positive women who need immediate referral to colposcopy from those who need early repeat HPV tests or recall on the basis of their disease status. We performed a literature review of publications and a manual search from 2010, reporting cytology, HPV partial genotyping, dual-staining and DNA methylation for triage of hrHPV positive tests, including their comparative performance between these methods as well as the effectiveness of some triage combinations with reference to HPV-based screening services in Europe. Cost effectiveness and the structure of triage algorithms for colposcopists also have been considered. From one report evaluating four options for triage as single options or as combined algorithms, partial genotyping for HPV 16 and 18 with dual-staining yielded the highest risk of cervical intraepithelial neoplasia grade three or worse within an HPV positive population and with an acceptable colposcopy rate. From a separate paper, this option appeared cost effective. However, publications were difficult to compare objectively. All options have their merits but a combination triage involving any two of cytology, HPV partial genotyping or dual-staining seems most efficient at present. HPV vaccination may impact upon the performance of future partial genotyping. DNA Methylation may become an acceptable future option.