Impact of HPV mRNA types 16, 18, 45 detection on the risk of CIN3+ in young women with normal cervical cytology

BACKGROUND: Despite a well-established cervical cancer (CC) screening program in Norway, the incidence of CC in young women is increasing, peaking at 35 years of age. 25 percent of all women diagnosed with CC had normal cytology within 3 years prior to cancer diagnosis, addressing the need to improve the screening programme to further reduce cancer incidences missed by cytology. OBJECTIVE: We wanted to investigate the detection rate of CIN3+ in women 25–39 years with normal cytology by using a 3-type HPV mRNA test as a targeted quality assurance measure. The control group is women with normal cytology. METHODS: During 2014–2017, samples from 13,021 women 25–39 years of age attending cervical cancer screening were analysed at Nordlandssykehuset, Bodø, Norway, including 1,896 women with normal cytology and HPV mRNA test (intervention group), and 11,125 women with cytology only (control group). The HPV mRNA testing was performed using a 3-type HPV E6/E7 mRNA test (PreTect SEE; direct genotyping 16, 18 and 45). The women were followed-up according to national guidelines throughout December 2021. RESULTS: Of the 13,021 women, 429 women (3.3%) had CIN3+ confirmed by biopsy in the follow-up, including 13 cases of invasive cervical cancer. Of the 1,896 women with normal cytology and HPV mRNA test (intervention group), 49 women (2.6%) had a positive test. The risks of CIN3+ among women with either a positive or negative HPV mRNA test were 28.6% (14/49) and 0.8% (14/1847). None of the women in the intervention group developed cervical cancer during follow-up. Of the 11,125 women with cytology only (control group), 712 women (6.4%) had abnormal cytology (ASC-US+). The risks of CIN3+ among women with abnormal and normal cytology were 17.7% (126/712) and 2.6% (275/10,413). CONCLUSION: By testing women 25–39 years of age with a normal cytology result using a specific 3-type HPV mRNA test, an increase in screening programme sensitivity can be achieved without an excessive additional workload. Women with normal cytology and a negative HPV mRNA test have a very low risk of cervical cancer.