National experience in the first two years of primary human papillomavirus (HPV) cervical screening in an HPV vaccinated population in Australia: observational study
Menée en Australie à partir de données portant sur 3 745 318 femmes vaccinées contre le papillomavirus humain (HPV) et ayant bénéficié d'un test HPV entre décembre 2017 et décembre 2019 (âge : de 25 à 69 ans), cette étude estime la proportion de patientes dont le résultat du test HPV est positif, la proportion de patientes ayant bénéficié d'une colposcopie ainsi que les taux de détection de lésions cervicales intraépithéliales de grade 2 ou plus et de lésions cancéreuses
Objective : To review the first two years of the primary human papillomavirus (HPV) cervical screening programme in an HPV vaccinated population.
Design : Observational study.
Setting Australia.
Participants : 3 745 318 women with a primary HPV test between 1 December 2017 and 31 December 2019; most women aged <40 years had previously been offered vaccination against HPV16 and HPV18.
Interventions : Primary HPV screening with referral if HPV16 or HPV18 (HPV16/18) positive and triage with liquid based cytology testing (threshold atypical squamous cells-cannot exclude high grade squamous intraepithelial lesion) for women who were positive for high risk HPV types other than 16/18. A 12 month follow-up HPV test was recommended in triaged women with a negative or low grade cytology result, with referral if they tested positive for any high risk HPV type at follow-up.
Main outcome measures : Proportion of women who had attended for their first HPV screening test, tested positive, and were referred for colposcopy; and short term risk of detecting cervical intraepithelial neoplasia (CIN) grade 2 or worse, CIN grade 3 or worse, or cancer.
Results : 54.6% (n=3 507 281) of an estimated 6 428 677 eligible women aged 25-69 had undergone their first HPV test by the end of 2019. Among those attending for routine screening, positivity for HPV16/18 and for HPV types not 16/18 was, respectively, 2.0% and 6.6% in women aged 25-69 (n=3 045 844) and 2.2% and 13.3% in highly vaccinated cohorts of women aged 25-34 (n=768 362). Colposcopy referral (ages 25-69 years) was 3.5%, increasing to an estimated 6.2% after accounting for women who had not yet had a 12 month repeat test. Cervical cancer was detected in 0.98% (456/46 330) of women positive for HPV16/18 at baseline, including 0.32% (89/28 003) of women with HPV16/18 and negative cytology. Women with HPV types not 16/18 and negative or low grade cytology at both baseline and 12 months were at low risk of serious disease (3.4% CIN grade 3 or worse; 0.02% cancer; n=20 019) but estimated to account for 62.0% of referrals for this screening algorithm.
Conclusions : Colposcopy referral thresholds need to consider underlying cancer risk; on this basis, women with HPV16/18 in the first round of HPV screening were found to be at higher risk regardless of cytology result, even in a previously well screened population. Women with HPV types not 16/18 and negative or low grade cytology showed a low risk of serious abnormalities but constitute most referrals and could be managed safely with two rounds of repeat HPV testing rather than one. HPV16/18 driven referrals were low in HPV vaccinated cohorts.
BMJ , article en libre accès, 2021