Missed opportunities for concomitant HPV vaccination among childhood cancer survivors.

Purpose: Childhood cancer survivors are at higher risk of human papillomavirus (HPV)-related second cancers than adolescents without cancer, yet their HPV vaccination uptake is lower. Using a statewide sample, we evaluated whether survivors are at higher risk of missed opportunities for concomitant HPV vaccination. Methods: From statewide healthcare data, we identified encounters where vaccines were received. Concomitant HPV vaccine missed opportunities were defined as a vaccine encounter where the HPV vaccine was not administered, although eligibility criteria were met. From these encounters, our sample included 327 survivors identified from the Utah Cancer Registry, diagnosed 2000-2016 at ages 0-9, and a birth year and sex-matched sample without cancer from the general population (n = 1,911). Mixed-effects Poisson regression estimated the rate of concomitant missed opportunities per vaccine encounter and 95% confidence intervals by vaccine encounter type (all vaccines, flu shot only, or adolescent/catch-up) from 2013 to 2016. Results: Survivors had more concomitant HPV vaccine missed opportunities than the population sample (70.0% vs. 59.0%). On average, survivors were 12% more likely to have missed opportunities at vaccine encounters and 4% more likely at flu shot only encounters. The predicted excess risk of concomitant missed opportunities for survivors ranged from 0.5 per10 vaccine encounters to 1.1 per10 vaccine encounters. Higher parental education, rurality, younger first vaccine age, and chemotherapy were associated with missed opportunities. Conclusions: Childhood cancer survivors have more missed opportunities for concomitant HPV vaccination than a population sample. As flu shots should be administered annually, providers have a regular opportunity to recommend and deliver the HPV vaccine to survivors. [ABSTRACT FROM AUTHOR]