The Future Control of Cervical Cancer

Hazel LewisPublic Health Physician

WellingtonCartwright Forum, 7 August 2015

NCSP-R

centralised

1965 1990 20001988

Cartwright Report

NCSP established

In 14 AHB

1996

NSU

Gisborne Inquiry (CSI)

McGoogan review

2001 2004

CCA

Legislation amended

NCSP-R outsourced

1999 Guidelines

2008 Guidelines incorporating HPV testing, LBC conversion

2008

History of cervical screening in New Zealand

2011

1st ParliamReview

Screening Trials In Thames, Wanganui, Otago, Waikato

2ndParliam Review

2015

Policies, stds reviews

NCSP research: HPV prevalence, modelling primary HPV, Compass study

Lab automation

Monitoring indicators reviewed and implemented

146 recs implemented

AuditsCancer case audits

Global Cervical Cancer Incidence, 2012

Global Cervical Cancer Mortality, 2012

Cervical cancer incidence trends (ASR (W) per 100,000)

Globocan, 2012

The next 10 years: Dual Prevention

We now have two powerful technologies to dramatically reduce cervical cancer incidence:- Screening for HPV infection- Immunisation against HPV

Success will depend on using both technologies together to achieve effective coverage in all groups

This will require better technologies, better guidelines, better information systems and better partnerships with all communities

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Dual prevention has its pitfalls

In principle, dual prevention should increase effective coverage and reduce gaps

Two concerns:

- Perception of protection

- Impact on cytology screening laboratories

Response:

- Education

- Change screening test from cytology to HPV

Challenges to implementing dual prevention

• Increase cervical screening coverage

• Co-ordinate components of the screening programme, close gaps (Who will do what? How much will communities be involved?)

• Improve quality of the screening programme

• Increase HPV vaccination coverage (2 doses?)

• Reduce inequalities between socio-economic and ethnic groups

• Minimise cost barriers – ‘free’ in primary care

• Improve co-ordination between screening and immunisation programmes

• Media involvement (change behaviours, minimise risks)

Programmes must be: easily affordable, effective, equitable

Screening for HPV infection

Cervical cancer is caused by infection with specific “high-risk” types of HPV (hrHPV)

15 hrHPV types identified in cervical cancers (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68, 73, 82)

Infection is common – only a few of infected women will develop cancer. Persistent infection (>2 years) more likely to lead to cervical cancer

Cancer slowly develops over a period of years from precursor lesions – CIN, making screening possible

hrHPV testing has been shown to provide a much better protection against CIN3 and cervical cancer than cytology

Natural history of HPV infection

Schiffman M, Castle P. N Engl J Med 2005, 353:2101-2104

Primary HPV screening Screening tests (cervical Pap smear, HPV) identify an existing pre-invasive cervical

lesion

Pap smear (ie cytology) has been the mainstay of cervical screening for past 60 years

However, increased awareness of limitations of cytology:

- Interpretation subjective, potential sources of error (lesion not sampled, abnormal cells may not be transferred, preservation of cells may be inadequate, may be reading errors)

- Single Pap low sensitivity (44-65%)

- Poor in preventing adenocarcinoma

- Poor PPV – unnecessary colposcopy

- Requires at least 3 yearly repeats

Effects of new HPV vaccines

Key clinical question that has informed change is the reduction in the burden of CIN3 and cervical cancer incidence and mortality by the combination of hrHPV testing and cytology (60-70% greater efficacy than cytology alone)

Primary HPV screening continued

- Impact on inequalities, as can self test with HPV

- Extending the screening interval from 3 to 5 years

- Education

- Effects on laboratories

- Transition phase, for safety reasons, given NZ cervical screening, should be considered

HPV testsTwo types:

- those that report pooled hrHPV types

- those that report the presence of HPV 16 and 18

HPV can be detected via DNA testing, RNA testing and testing of cellular markers of HPV

Specimens can be obtained using a swab, broom, brush or tampon which is then placed in a transport medium

Over 100 tests available worldwide but not comparable

A test can be falsely negative – important to standardise the quality of test used

New clinical guidelines for cervical screening

Key clinical questions must inform change:

What are the benefits and potential harms of HPV screening with cytology triage?

What are the benefits and harms of starting screening at 20, 25 or 30 years and when to stop?

What is the best screening interval?

Accuracy of self collected specimens?

Immunisation against HPV Introduced on 1 September 2008

Provided for year 8 (11-12 year old girls)

Programme targeted and tailored implementation to achieve equity

Mixed school based and primary care delivery

Vaccine uptake higher when evidence of integration and information sharing across components of the Programme (community engagement, primary care and school based delivery systems)

Improvements should address misinformation about HPV vaccine, integration of delivery systems, possible health equity mechanisms (role of and levers available to primary health organisations locally)

HPV vaccine – current issues

Full HPV vaccine coverage (3 doses) well below target

Coverage falls after 1st dose

Girls only, offered free vaccine

Impact on current cytology based screening (high grade lesions)

Absence of data linkage - Immunisation Register with NCSP Register, therefore unable to monitor effectively

HPV immunised women may not be screened, and will be at risk for cervical cancer

Key health education messages (HPV vaccine and screening) should be part of ongoing communication strategy

Future developments in HPV immunisation

Nonavalent vaccines (CE studies) FDA approved Gardasil 9, Dec 2014 with HPV types

6/11/16/18/31/33/45/52/58 Two dose regimens should be explored Better integration of HPV vaccine with screening

- Information systems (data linkage)

- Education

- Workforce Greater involvement / empowerment of communities

Summary: Future Control of Cervical Cancer

Dual prevention Better technologies

- Screening test (hrHPV)

- Vaccine (nonavalent) Better implementation

- New clinical guidelines

- ‘New’ register for cervical screening (Integrated Data Infrastructure)

- Data linkage of two registers (NCSP-R and NIR within IDI)

- Community Partnerships Timely analysis and publication