Partial HPV vaccination linked to cervical intraepithelial neoplasia decreases
Partial HPV vaccination has resulted in population-level decreases in cervical intraepithelial neoplasia, according to research published in JAMA Oncology.
These data may be used to support increasing the cervical cancer screening age, according to the researchers.
“Persistent infection with HPV can cause high-grade cervical intraepithelial neoplasia, which can progress to invasive cervical cancer,” Cosette M. Wheeler, PhD, regent’s professor of pathology and obstetrics and gynecology at University of New Mexico Health Sciences Center, and colleagues wrote. “Randomized trials have shown that HPV vaccines are efficacious in preventing HPV infection and low-grade and high-grade cervical intraepithelial neoplasia, and cervical cancer reductions of 70% to 90% are envisioned to be possible through population vaccination during the next 25 years.”
Wheeler and colleagues studied population-based trends in the incidence of cervical intraepithelial neoplasia that overlapped with implementation of HPV vaccination.
The researchers used data collected between January 2007 and December 2014 in the New Mexico HPV Pap Registry — the only nationwide surveillance system to capture population-based estimates of cervical cancer screening and cervical intraepithelial neoplasia incidence since the introduction of the HPV vaccination.
The researchers calculated annual percentage changes to analyze cervical intraepithelial neoplasia trends during the study period.
The incidence of low-grade (CIN1) and high-grade (CIN2 and CIN3) cervical intraepithelial neoplasia served as the study’s primary outcome measure.
The researchers observed 13,520 cases of CIN1, 4,296 cases of CIN2 and 2,823 cases of CIN3 diagnosed in females aged 15 years to 29 years during the study period.
Significant annual percentage decreases occurred for females aged 15 years to 19 years for CIN1 (–9; P < .001), CIN2 (–10.5; P = .03) and CIN3 (–41.3; P = .05).
Women aged 20 years to 24 years also experienced a significant decrease of –6.3 in CIN2 incidence (P = .02).
Conversely, cervical intraepithelial neoplasia incidence increased in women aged 25 years to 29 years, with significant increases in CIN1 (P = .05) and CIN3 (P = .002).
Cervical cytology screening rates significantly decreased during the study period (P < .001 for all age groups).
“Overall, our data demonstrate that clinical outcomes of cervical intraepithelial neoplasia will be reduced among cohorts partially vaccinated for HPV, which will change clinical practice and reduce the cost-effectiveness of current clinical care that supports cervical cancer prevention,” Wheeler and colleagues wrote. “Most important, screening modalities and strategies, as well as clinical management algorithms, will need to evolve as we work toward a rational integration of HPV vaccination and cervical screening.” – by Cameron Kelsall
Disclosure: Wheeler reports grants received by her employer from the NCI and the National Institute of Allergy and Infectious Diseases during the conduct of this study, as well as other support from GlaxoSmithKline, Merck and Roche Molecular Systems outside the submitted work. Please see the full study for a list of all other researchers’ relevant financial disclosures.