Human Papillomavirus Laboratory Testing: the Changing Paradigm Eileen M. Burd Emory University School of Medicine, Department of Pathology and Laboratory Medicine, and Emory University School of Medicine, Department of Medicine, Division of Infectious Diseases, Atlanta, Georgia, USA SUMMARY ..................................................................................................................................................291 INTRODUCTION ............................................................................................................................................291 OROPHARYNGEAL CANCER ................................................................................................................................296 ANAL CANCER ..............................................................................................................................................298 CERVICAL CANCER .........................................................................................................................................300 Current Cervical Cancer Screening Guidelines ...........................................................................................................301 COMMERCIALLY AVAILABLE TEST SYSTEMS FOR HPV DETECTION IN THE CLINICAL LABORATORY ....................................................303 HPV Molecular Detection Methods .......................................................................................................................303 DNA-Based Tests: Signal Amplification ..................................................................................................................306 HC2 HPV DNA test .....................................................................................................................................306 Cervista HPV HR test ...................................................................................................................................307 DNA-Based Tests: Target Amplification ..................................................................................................................307 cobas 4800 HPV test ...................................................................................................................................307 E6/E7 mRNA PCR (Reverse Transcriptase PCR) ............................................................................................................308 HIGH-RISK HPV DETECTION AS A FIRST-LINE TEST IN PRIMARY CERVICAL CANCER SCREENING ........................................................308 THE ROLE OF HPV GENOTYPING ...........................................................................................................................310 HPV SURVEILLANCE FOLLOWING COLPOSCOPY TREATMENT............................................................................................311 FUTURE CHALLENGES ......................................................................................................................................311 REFERENCES ................................................................................................................................................312 AUTHOR BIO ................................................................................................................................................319 SUMMARY High-risk human papillomaviruses (HPVs) cause essentially all cervical cancers, most anal and oropharyngeal cancers, and some vaginal, vulvar, and penile cancers. Improved understanding of the pathogenesis of infection and the availability of newer tests are changing the approach to screening and diagnosis. Molecular tests to detect DNA from the most common high-risk HPVs are FDA approved for use in conjunction with cytology in cervical cancer screening programs. More-specific tests that detect RNA from high-risk HPV types are now also available. The use of molecular tests as the primary screening tests is being adopted in some areas. Genotyping to identify HPV16 and -18 has a recommended role in triaging patients for colposcopy who are high-risk HPV positive but have normal cytology. There are currently no recommended screening methods for anal, vulvar, vaginal, penile, or oropharyn- geal HPV infections. HPV testing has limited utility in patients at high risk for anal cancer, but p16 immunohistochemistry is rec- ommended to clarify lesions in tissue biopsy specimens that show moderate dysplasia or precancer mimics. HPV testing is recom- mended for oropharyngeal squamous cell tumors as a prognostic indicator. Ongoing research will help to improve the content of future guidelines for screening and diagnostic testing. INTRODUCTION P apillomaviruses are common worldwide and are known to infect birds and most mammals, including humans. Because of similar structure, papillomaviruses and polyomaviruses were initially taxonomically positioned in the same family, Papoviridae. Both are small (40- to 60-nm) viruses with nonenveloped icosa- hedral capsids and carry their genetic material as circular double- stranded DNA associated with histones. The size of the genome is about 8 kb for papillomaviruses and 5 kb for polyomaviruses, and, with the exception of a small homologous segment in the poly- omavirus T-antigen and papillomavirus E1 genes that correspond to a helicase, they do not share any substantial sequence similarity. Further, although both viruses replicate in the host cell nucleus, the replication strategies are very different, with papillomavirus DNA transcription occurring on only one DNA strand in one direction while polyomavirus DNA replication is bidirectional. Because of these differences, papillomaviruses have been sepa- rated into their own family, Papillomaviridae. Papillomaviruses contain stable DNA genomes that are replicated with high fidelity by the host cell machinery. Sequence changes by mutation or re- combination are rare events and appear to occur at frequencies similar to those in the DNA genomes of the infected host. Papil- lomaviruses are generally considered to be species specific; how- ever, there are rare reports of cross-species infection, such as hu- man papillomavirus DNA associated with cutaneous squamous lesions of the cat (1, 2). Human papillomavirus (HPV) is the broad term referring to the group of related papillomavirus strains that infect humans. HPV genomes are similarly organized and are divided into three major regions (early genes, late genes, and an upstream regulatory region) separated by two polyadenylation (pA) sites (early pA and Published 24 February 2016 Citation Burd EM. 2016. Human papillomavirus laboratory testing: the changing paradigm. Clin Microbiol Rev 29:291–319. doi:10.1128/CMR.00013-15. Address correspondence to eburd@emory.edu. Copyright © 2016, American Society for Microbiology. All Rights Reserved. crossmark April 2016 Volume 29 Number 2 cmr.asm.org 291 Clinical Microbiology Reviews on June 1, 2020 by guest http://cmr.asm.org/ Downloaded from