Data show longer intervals between HPV testing likely safe

Key takeaways:

• Data suggest HPV testing provides greater long-term protection against cervical precancer than cytology.
• HPV testing 8 years after a negative result was comparable to testing 5 years after negative cytology.

A 5-year interval between cervical cancer screenings using HPV testing does not increase risk for cervical precancer detection compared with cytology every 3 years and may be a more effective screening method long term, researchers report.

The U.S. has gradually transitioned from cytology to HPV-based screening for cervical cancer over the past 20 years, according to Anna Gottschlich, PhD, MPH, assistant professor of population science at Wayne State University School of Medicine. The U.S. Preventive Services Task Force currently recommends one of three options for routine cervical cancer screening: cytology screening every 3 years; HPV screening every 5 years; or co-testing with HPV and cytology screening every 5 years.

“HPV screening performs better than cytology at identifying cervical precancers,” Gottschlich told Healio. “Due to the superiority of the HPV test to detect cervical precancers, the risk for detection of cervical precancers is lower after a negative HPV test compared with cytology. In fact, we found that the risk 5 years after a negative HPV screen was lower than the risk 3 years after a negative cytology screen, which is the current recommended interval for routine cytology-based screening. Our findings confirm that HPV testing provides greater long-term protection against cervical precancer than cytology.”

For the longitudinal study, researchers analyzed data from women and people with a cervix who received one (n = 5,546) or two (n = 6,624) negative HPV screens during the HPV FOCAL randomized trial and from women with one (n = 782,297) or two (n = 673,778) normal cytology results using data from the provincial screening registry in British Columbia, Canada. Participants from each cohort were aged 25 to 65 years at the initial screening. Researchers followed all participants for 14 years and compared long-term risk for cervical intraepithelial neoplasia grade 2 or worse and grade 3 or worse.

The findings were published in Cancer Epidemiology, Biomarkers & Prevention.

At 8 years, researchers found that the cumulative risks for cervical intraepithelial neoplasia grade 2 or worse were 3.2 of 1,000 among people who received one negative HPV screening (95% CI, 1.6-4.7) and 2.7 of 1,000 for people who received two negative HPV screenings (95% CI, 1.2-4.2). This was comparable to the risk among women who received cytology only after 3 years follow-up, with an incidence of 3.3 of 1,000 (95% CI, 3.1-3.4) and 2.5 of 1,000, respectively (95% CI, 2.4-2.6).

Cumulative risk for cervical intraepithelial neoplasia grade 2 or worse after 10 years was low in both HPV cohorts, at 4.7 of 1000 (95% CI, 2.6-6.7) and 3.9 of 1,000, respectively (95% CI, 1.1-6.6).

The researchers noted that differences in drop-out and screening rates in the trials may have made the HPV groups less comparable during the study; however, loss to follow-up was low. The study was also conducted in a well-screened population; results are not directly applicable to low-resource settings.

“This study confirmed earlier findings that the extended 5-year interval between HPV screens does not increase risk for cervical precancer detection, and in fact, the 5-year interval is more effective than cytology every 3 years,” Gottschlich told Healio. “As the U.S. transitions from cytology and co-testing to primary HPV screening, further research is needed to identify optimal implementation strategies. For example, we need more information regarding the appropriate age to enter and exit screening programs and optimal triage strategies after an abnormal HPV screen.”

The researchers noted they will continue to follow the cohorts to better understand optimal implementation strategies for HPV screening, including appropriate ages for entry and exit into screening and triage management strategies.

For more information:

Anna Gottschlich, PhD, MPH, can be reached at gottschlicha@karmanos.org; X (Twitter): @AnnaGottschlich.