Clinical relevance of partial HPV16/18 genotyping in stratifying HPV-positive women attending routine cervical cancer screening: a population-based cohort study.

OBJECTIVE: To evaluate partial HPV16/18 genotyping as a possible biomarker to select women attending HPV-based cervical cancer screening at higher risk to be referred to colposcopy. DESIGN: Population-based cohort study. SETTING: Organised cervical cancer screening programmes (Italy). POPULATION: Women with high-risk HPV infection (period: 2015-2019). METHODS: We analysed the association between partial HPV16/18 genotyping, cytology triage and histologically confirmed diagnosis of high-grade cervical intraepithelial neoplasia (CIN3+ ) lesions. MAIN OUTCOME MEASURES: Detection rate (DR) and positive predictive value (PPV) for histologically confirmed CIN3+ (any episode in the 2 years after baseline); sensitivity for CIN3+ and number of colposcopies needed for lesion detection. RESULTS: The study included 145 437 women screened with HPV testing by the clinically validated COBAS 4800 HPV assay (Roche). Overall, 9601 (6.6%) women were HPV+ at baseline; HPV16 and HPV18 were present in 1865 and 594 samples, respectively. The cumulative (baseline plus 1-year repeat) cytology positivity was 42.8% and high-grade cytology was significantly higher (P < 0.0001) among women with HPV16 infection at baseline (15.2%). The cumulative CIN3+ DR for women with HPV16, HPV18 and other HPV-type infections was 9.8%, 3.4% and 1.8%, respectively. CONCLUSIONS: Partial HPV16 genotyping may play a role in triage, whereas HPV18 seems to behave much more similarly to the other HPV types and does not provide additional stratification. HPV16 genotyping combined with high-grade cytology can be envisaged as a triage biomarker in cervical screening to maximise CIN3+ detection while minimising colposcopy at baseline or 1-year repeat. TWEETABLE ABSTRACT: HPV16 genotyping combined with high-grade cytology can be used as triage biomarker for CIN3+ in HPV-positive women.