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Hampson IN, Oliver AW, Hampson L. Potential Effects of Human Papillomavirus Type Substitution, Superinfection Exclusion and Latency on the Efficacy of the Current L1 Prophylactic Vaccines. Viruses 2020; 13:v13010022. [PMID: 33374445 PMCID: PMC7823767 DOI: 10.3390/v13010022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 12/22/2020] [Accepted: 12/22/2020] [Indexed: 12/16/2022] Open
Abstract
There are >200 different types of human papilloma virus (HPV) of which >51 infect genital epithelium, with ~14 of these classed as high-risk being more commonly associated with cervical cancer. During development of the disease, high-risk types have an increased tendency to develop a truncated non-replicative life cycle, whereas low-risk, non-cancer-associated HPV types are either asymptomatic or cause benign lesions completing their full replicative life cycle. HPVs can also be present as non-replicative so-called “latent” infections and they can also show superinfection exclusion, where cells with pre-existing infections with one type cannot be infected with a different HPV type. Thus, the HPV repertoire and replication status present in an individual can form a complex dynamic meta-community which changes with respect to both time and exposure to different HPV types. In light of these considerations, it is not clear how current prophylactic HPV vaccines will affect this system and the potential for iatrogenic outcomes is discussed in light of recent outcome data.
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Maza M, Schocken CM, Bergman KL, Randall TC, Cremer ML. Cervical Precancer Treatment in Low- and Middle-Income Countries: A Technology Overview. J Glob Oncol 2017; 3:400-408. [PMID: 28831448 PMCID: PMC5560450 DOI: 10.1200/jgo.2016.003731] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cervical cancer is the fourth leading cause of cancer-related death in women worldwide, with 90% of cases occurring in low- and middle-income countries (LMICs). There has been a global effort to increase access to affordable screening in these settings; however, a corresponding increase in availability of effective and inexpensive treatment modalities for ablating or excising precancerous lesions is also needed to decrease mortality. This article reviews the current landscape of available and developing technologies for treatment of cervical precancer in LMICs. At present, the standard treatment of most precancerous lesions in LMICs is gas-based cryotherapy. This low-cost, effective technology is an expedient treatment in many areas; however, obtaining and transporting gas is often difficult, and unwieldy gas tanks are not conducive to mobile health campaigns. There are several promising ablative technologies in development that are gasless or require less gas than conventional cryotherapy. Although further evaluation of the efficacy and cost-effectiveness is needed, several of these technologies are safe and can now be implemented in LMICs. Nonsurgical therapies, such as therapeutic vaccines, antivirals, and topical applications, are also promising, but most remain in early-stage trials. The establishment of evidence-based standardized protocols for available treatments and the development and introduction of novel technologies are necessary steps in overcoming barriers to treatment in LMICs and decreasing the global burden of cervical cancer. Guidance from WHO on emerging treatment technologies is also needed.
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Affiliation(s)
- Mauricio Maza
- Mauricio Maza, Katherine L. Bergman, and Miriam L. Cremer, Basic Health International, New York, NY; Celina M. Schocken, Pink Ribbon Red Ribbon, Washington, DC; Thomas C. Randall, National Cancer Institute, Massachusetts General Hospital, Boston, MA; and Miriam L. Cremer, Cleveland Clinic, Cleveland, OH
| | - Celina M. Schocken
- Mauricio Maza, Katherine L. Bergman, and Miriam L. Cremer, Basic Health International, New York, NY; Celina M. Schocken, Pink Ribbon Red Ribbon, Washington, DC; Thomas C. Randall, National Cancer Institute, Massachusetts General Hospital, Boston, MA; and Miriam L. Cremer, Cleveland Clinic, Cleveland, OH
| | - Katherine L. Bergman
- Mauricio Maza, Katherine L. Bergman, and Miriam L. Cremer, Basic Health International, New York, NY; Celina M. Schocken, Pink Ribbon Red Ribbon, Washington, DC; Thomas C. Randall, National Cancer Institute, Massachusetts General Hospital, Boston, MA; and Miriam L. Cremer, Cleveland Clinic, Cleveland, OH
| | - Thomas C. Randall
- Mauricio Maza, Katherine L. Bergman, and Miriam L. Cremer, Basic Health International, New York, NY; Celina M. Schocken, Pink Ribbon Red Ribbon, Washington, DC; Thomas C. Randall, National Cancer Institute, Massachusetts General Hospital, Boston, MA; and Miriam L. Cremer, Cleveland Clinic, Cleveland, OH
| | - Miriam L. Cremer
- Mauricio Maza, Katherine L. Bergman, and Miriam L. Cremer, Basic Health International, New York, NY; Celina M. Schocken, Pink Ribbon Red Ribbon, Washington, DC; Thomas C. Randall, National Cancer Institute, Massachusetts General Hospital, Boston, MA; and Miriam L. Cremer, Cleveland Clinic, Cleveland, OH
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