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New Zealand Perspectives of HPV vaccination and Genital Tract Neoplasia. Sept 2006 Peter Sykes. Hpv 16/186/11. Age 9-26 3 vaccinations. MERCK. cervarix. Hpv 16/18. Cervical cancer is an important cause of mortality and morbidity particularly in developing countries. .
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New Zealand Perspectives of HPV vaccination and Genital Tract Neoplasia Sept 2006 Peter Sykes
Hpv 16/186/11 Age 9-26 3 vaccinations MERCK cervarix Hpv 16/18
Cervical cancer is an important cause of mortality and morbidity particularly in developing countries. • Commonest in subsahara and central/south america • 1 in 10 cancers • 90% life lost in developing countries
Sexual contact Acute hpv infection Persistent hpv infection Integration of hpv DNA Accumulation of mutation Invasion Normal CIN 1/HPV CIN2/3 Cancer HPV infection is an obligatory step in the development of cervical cancer 10 to 30 yrs
Barriers to HPV prevention • Prevalence of HPV infection • 30-40%14 and 15 yr old have had sex • Lack of culture medium • Numerous HPV types (96)
14.6 16 18 69.7 45 25.7 17 52.5 67.6 12.6 31 33 57 52 58 Others Prevalence of HPV Types in Cervical Cancer HPV Type North America/ Europe South Asia Northern Africa Central/South America *A pooled analysis and multicenter case control study (N = 3607) 1. Muñoz N, Bosch FX, Castellsagué X, et al. Int J Cancer. 2004;111:278–285.
HPV 16 and 18 VLP vaccines are a major medical advance • Produces a stronger immune response than infection • No risk of infection • Prevents persistent infection • Has the potential to reduce the risk of cervical cancer by about 70% • Has the potential to reduce the risk of other hpv related cancers
Vaccination hpv 16, 18 almost eliminates 16/18 related disease at 24 months Modified-intention-to-treat population Subjects are counted once in each applicable endpoint category. A subject may appear in more than one category. *Cases per 100 person years at risk. n = received ≥ 1 vaccination; includes protocol violations; HPV 6, 11, 16 or 18 sero(-) and HPV 6, 11, 16 or 18 DNA(-) at Day 1; Cases counted starting one month post-dose 1
Abnormal cervical cytology causes significant morbidity and resource utilisation in NZ women
The impact of abnormal cervical cytology • Psychological impact • Repeat cytology (cost) • Colposcopy • Treatment • Reproductive impact • Follow up colposcopy • Annual cytology
The burden of abnormal cytology in NZ • 400,000 smears per annum • 30,000 abnormal • 4,000 have high grade smears • Approx 5,000 have high grade abnormalities that need treatment • Thousands more are treated for low grade abnormalities CWH colposcopy Clinc • 1100 new patients • 3000 colposcopies
A large proportion of cervical abnormalities can be prevented by hpv vaccination • 63% CIN3 /AIS hpv 6,11,18,16 pos • 40% CIN any grade hpv 6,11,18,16 pos • 10% reduction cin smear • 16% reduction in treatment cin • 25% reduction rx warts Proportion of cin3 or worse assc with16,18,6,11.
Genital warts are a common cause of unpleasant and troublesome morbidity • 1% sex active people • Require multiple RX • 30,000 sex heath clinic appts • 90% hpv 6 and 11
Young New Zealand women should be educated about HPV infection encouraged to undergo vaccination • Vaccine well tested and no serious side effects • Demonstrated short term benefit reduction of CIN • Benefit likely regardless of sexual history • HPV testing not required • (prevention of warts gardasil) BUT • Cervical screening recommendations are unchanged. • Long term benefits unproven (but likely) • Provided screening is adhered to the risk of cervical cancer is low.
Cervical screening recommendations unchanged • Current commercial tests do not allow investigation of HPV status pre vaccination. • Cervical screening below age 20 is not indicated. • Risk of CIN and cancer persists. • Interval of screening is dependent on natural history of disease and sensitivity of test.
A population based strategy of HPV vaccination has the potential to significantly reduce the future incidence of cervical cancer and other HPV related genital tract cancers.
In 2001 189 new registrations of cervical cancer 24 women anal, 42 vulval and 14 vaginal cancer.
Cervical cancer epidemiology is characterised by its falling incidence and mortality and inequalities of race and socioeconomic status
The decrease in cervical cancer has been dramatic !How rare will it be in 2035?
Cervical cancer is most frequent in the poorly screened population. • Older women • Maori • Immigrant population • Low Socioeconomic status
Only a population based vaccination program will reduce cancer mortality. • 100% effective given to 100% population may reduce incidence by 50-80% • Difficult to reach populations • Need to vaccinate prior to sexual activity • Lag time of 10-30 years • Immigrant populations may influence incidence
Other Considerations • Long term data very limited • Unknown acceptance in NZ population • The epidemiology of HPV and cervical cancer could change • Vaccination could change screening behaviour • Other HPV related cancers may be increasing
The cost of a national vaccination program is likely to be difficult to justify on the basis of cancer prevention. • High cost of vaccine • Small number of lives saved • advanced age of women with advanced cancer • Current high expenditure on cervical cancer prevention • Competing vaccinations • Could the money be better spent • The vaccination of high incidence populations should be considered.
The cost benefit of prevention of screen detected abnormalities (and warts) by hpv vaccination must be carefully considered. • The cost of screen detected abnormalities need to be calculated. • The epidemiology of HPV serotypes and CIN in NZ needs further study • Long term vaccination data required • Modelling needs to account for future epidemiological and screening trends.
Cervical cancer prevention is an important emotive and political issue. 1988
Cervical cancer has a particular emotive impact • Fear of cancer • Body image • Sexuality • Reproduction • Devastating symptoms • Stigma of STI
Ethnic disparities of Ca Cervix • Maori have greater incidence and mortality • Maori less uptake of screening • Greater delays in treatment • Poorer prognosis • Opportunistic vaccination could increase disparities • Population based vaccination could decrease them.
HPV vaccine in NZ • Major Medical Breakthrough • HPV vaccination should be encouraged in young women Cervical screening must continue • More information on the cost benefit of vaccination is required The risk of cervical cancer in screened women is very low • Funding is a Political issue