Randomized Controlled Trial of Human Papillomavirus Testing in Primary Cervical Cancer Screening (SWEDESCREEN)

Swedish Cancer Society, Europe Against Cancer (European Union Directorate General XII- Public Health)

Human papillomavirus (HPV)-based cervical screening is known to increase sensitivity for detection of high-grade cervical intraepithelial neoplasia (CIN). Randomized trials of longitudinal efficacy are required to assess whether these gains represent overdiagnosis or a protective effect. Methods: A total of 12527 women, aged 32-38, attending population-based invitational screening in Sweden were randomized 1:1 to HPV test and cytology (intervention arm) or cytology only (control arm). HPV-positive women were invited for a second HPV test at least one year later and women with type-specific persistent infections were then invited to colposcopy. A similar number of random double-blinded procedures are performed in the control arm. Women are followed with comprehensive registry-based follow-up. Primary outcome is the relative rates of CIN grade 2 or worse (CIN2/CIN3+) found in subsequent screening. Secondary outcomes are the relative rates of CIN2/CIN3+ found in the aseline screening and outcomes stratified by grade of CIN (CIN 2 or CIN3+).

Incidence of CIN2/CIN3+ lesions (which includes invasive cancers and in situ adenocarcinomas) found by subsequent screening (i.e. after the enrollment screening round and its associated follow-up).

Secondary outcomes were the incidence of CIN2/CIN3+ lesions at enrollment screening (including associated follow-up) and outcomes stratified by CIN2 and CIN3+ lesions as endpoints.

Inclusion Criteria: Women aged 32-38 years old Attending the Swedish population-based organised cervical screening program Exclusion Criteria: Not providing informed consent

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