Objective: We conducted a baseline study of human papillomavirus (HPV) type prevalence in invasive cervical cancers (ICCs) using data from 7 cancer registries (CRs) in the United States. Cases were diagnosed between 1994 and 2005 before the implementation of the HPV vaccines.
Materials and methods: Cancer registries from Florida, Kentucky, Louisiana, Michigan, Hawaii, Iowa, and Los Angeles, California identified eligible ICC cases and obtained sections from representative blocks of archived tumor specimens for DNA extraction. All extracts were assayed by linear array and, if inadequate or HPV negative, retested with INNO-LiPA Genotype test. Clinical and demographic factors were obtained from the CRs and merged with the HPV typing data to analyze factors associated with different types and with HPV negativity.
Results: A total of 777 ICCs were included in this analysis, with broad geographic, age, and race distribution. Overall, HPV was detected in 91% of cases, including 51% HPV-16, 16% HPV-18 (HPV-16-negative), and 24% other oncogenic and rare types. After HPV-16 and -18, the most common types were 45, 33, 31, 35, and 52. Older age and nonsquamous histology were associated with HPV-negative typing.
Conclusions: This study provides baseline prevaccine HPV types for postvaccine ICC surveillance in the future. HPV-16 and/or -18 were found in 67% of ICCs, indicating the potential for vaccines to prevent a significant number of cervical cancers.