In a systemic analysis of global literature reported in The Lancet, Wei et al estimated the proportion of invasive cervical cancer cases caused by specific human papillomavirus (HPV) genotypes.
Study Details
A literature search through February 2024 was performed to identify studies reporting HPV genotype–specific prevalence in women with invasive cervical cancer and in women with normal cervical cytology. Odds ratios were estimated by comparing HPV genotype–specific prevalence among patients with HPV-positive invasive cervical cancer and individuals with normal cervical cytology in a model adjusting for region, year of paper publication, and HPV primer or test; HPV genotypes with a lower bound of the 95% confidence interval of the odds ratio >1.0 were considered to be causal for invasive cervical cancer.
Key Findings
The analysis included 1,174 studies with 111,902 cases of HPV-positive invasive cervical cancer and 2,755,734 individuals with normal cervical cytology. A total of 17 HPV genotypes were considered causal for invasive cervical cancer, with odds ratios for presence in invasive cervical cancer cases vs individuals with normal cytology ranging from 48.3 (95% confidence interval [CI] = 45.7–50.9) for HPV16 and 12.5 (95% CI = 11.6–13.6) for HPV18 to 1.6 (95% CI = 1.3–1.8) for HPV56 and 1.4 (95% CI = 1.2–1.7) for HPV51.
HPV16 had the highest global attributable fraction to invasive cervical cancer (61.7%), followed by HPV18 (15.3%), HPV45 (4.8%), HPV33 (3.8%), HPV58 (3.5%), HPV31 (2.8%), and HPV52 (28%). The remaining causal genotypes (HPV35, 59, 39, 56, 51, 68, 73, 26, 69, and 82) had a combined global attributable fraction of 5.3%.
Attributable fractions for HPV16 and 18 combined and HPV16, 18, 31, 33, 45, 52, and 58 combined (the causal genotypes with the highest attributable fractions) were lowest in Africa (71.9% and 92.1%, respectively) and highest in central, western, and southern Asia (83.2% and 95.9%, respectively). HPV35 had a higher attributable fraction in Africa (3.6%) than in other regions (range = 0.6%–1.6%). In other regions, respective attributable fractions were 75.5% and 95.3% in eastern and southeastern Asia, 73.3% and 93.6% in Latin America and the Caribbean, 80.9% and 95.8% in North America, and 79.4% and 94.2% in Oceania.
The investigators concluded, “This study provides a comprehensive global picture of HPV genotype–specific attributable fractions in invasive cervical cancer, before the influence of HPV vaccination. These data can inform HPV genotype–specific vaccination and screening strategies to reduce the burden of invasive cervical cancer.”
Gary M. Clifford, PhD, of the International Agency for Research on Cancer (IARC/WHO), Early Detection, Prevention and Infections Branch, Lyon, France, is the corresponding author for The Lancet article.
Disclosure: The study was funded by the EU Horizon 2020 Research and Innovation Programme. For full disclosures of the study authors, visit thelancet.com.
