RESUMO
Less frequent cervical cancer screening in human papillomavirus (HPV) vaccinated birth cohorts could produce considerable savings without increasing cervical cancer incidence and loss of life-years. We report here the baseline findings and interim results of safety and accuracy of infrequent screening among HPV16/18 vaccinated females. The entire 1992-1994 birth-cohorts (30,139 females) were invited to a community-randomized HPV16/18-vaccination trial. A total of 9,482 female trial participants received HPV16/18-vaccination in 2007-2009 at age of 13-15. At age 22, 4,273 (45%) of these females consented to attend a randomized trial on frequent (ages 22/25/28; Arm 1: 2,073 females) vs. infrequent screening (age 28; Arm 2: 2,200 females) in 2014-2017. Females (1,329), who had got HPV16/18 vaccination at age 18 comprised the safety Arm 3. Baseline prevalence and incidence of HPV16/18 and other high-risk HPV types were: 0.5% (53/1,000 follow-up years, 104 ) and 25% (2,530/104 ) in the frequently screened Arm 1; 0.2% (23/104 ) and 24% (2,413/104 ) in the infrequently screened Arm 2; and 3.1% (304/104 ) and 23% (2,284/104 ) in the safety Arm 3. Corresponding prevalence of HSIL/ASC-H and of any abnormal cytological findings were: 0.3 and 4.2% (Arm 1), 0.4 and 5.3% (Arm 2) and 0.3 and 4.7% (Arm 3). Equally rare HSIL/CIN3 findings in the infrequently screened safety Arm A3 (0.4%) and in the frequently screened Arm 1 (0.4%) indicate no safety concerns on infrequent screening despite the up to 10 times higher HPV16/18 baseline prevalence and incidence in the former.