Summary

initiative in Australia, halving cervical cancer incidence and mortality since it was introduced in 1991. This has been achieved through organised, population-based cervical screening using 2-yearly Pap tests to detect precancerous changes to cervical cells, allowing treatment before any progression to cervical cancer, thereby preventing this disease. Cervical screening using Pap tests has been supported by high-quality cervical cytology through pathology laboratories, and by state and territory cervical cytology registers, that supported appropriate recommendations for clinical management, and provided a safety net to women who participated in cervical screening.

Improvements in technology, a greater understanding of the role of human papillomavirus (HPV) in the development of cervical cancer, and the introduction of an HPV vaccine that is now administered to girls and boys under the National Immunisation Program, led to a process by which the NCSP was reviewed and ‘renewed’, to ensure that the NCSP continued to provide Australian women with safe and effective cervical screening. As a result of this process, on 1 December 2017, a ‘renewed’ NCSP was introduced.

The renewed NCSP changes the way that women are screened. Instead of women aged 20–69 having a Pap test every 2 years, women aged 25–74 now have a Cervical Screening Test (CST) every 5 years (the CST is an HPV test, followed by a cytology test if HPV is found). Another change is the collection of cervical screening data by the National Cancer Screening Register (NCSR), which is now the sole source of cervical screening data.

Two years after its commencement, this is the first report to present data for the renewed NCSP. This report introduces the 20 performance indicators that will be used to monitor the NCSP going forward, and presents data against 9 of those for which data exist and have been deemed of adequate completeness for inclusion. Others that cannot be reported at this time will appear in future reports.

In considering the data contained within this report, it should be noted that this is a new program with a new source of data, some of which are incomplete. It is expected that data completeness will improve in future, allowing for more comprehensive reporting. Data not considered of adequate completeness to provide useful estimates were colposcopy and histology. This report therefore focuses on recruitment and screening in the renewed NCSP.

As a result of significant changes to the NCSP that was implemented in Australia from 1 December 2017, it must be recognised that program data presented in this report are not comparable to data published in previous years. Further, due to insufficient time having elapsed to adequately measure all performance indicators, in addition to current limitations of data held in the NCSR, this report presents a snapshot that is transitional in nature and cannot be considered directly comparable to data that will be published in future reports.

Participation

Participation refers to the number of women who had a cervical screening test over a certain period of time. Participation in the new 5-year program cannot be properly reported until there are 5 years of data available. In the interim, preliminary estimates have been calculated. Over the 2 years 2017–2018, participation in cervical screening by women aged 25–69 was 53% of the eligible population, and over the 3 years 2016–2018, participation was 68%. These crude rates include pre-renewal and post-renewal data, and include women aged 25–69 who had any cervical screening test (Pap or HPV test) over the reporting period.

A single year estimate of participation of 54% (that includes only women aged 25–74 who had an HPV test under the renewed NCSP) has also been produced for 2018. This single-year estimate mirrored previously-observed trends—participation in cervical screening decreased with increasing remoteness (43% in Very remote areas compared with 54% in Major cities) and decreased with increasing socioeconomic disadvantage (48% in areas of most disadvantage compared with 60% in areas of least disadvantage).

Response to invitation

Under the renewed NCSP, women are invited to screen (or to rescreen if they have screened before). In 2018, 20% of women aged 25–74 who were invited to screen or rescreen had an HPV test within 6 months.

Rescreening

Rescreening looks at the time between a woman’s HPV test in 2018 and her last normal Pap test in the preceding 5 years. Of the women aged 25–74 screened in 2018 who had a normal Pap test within the preceding 5 years, 76% rescreened appropriately, meaning that their HPV test was between 21 months and 3 years after their last normal Pap test. In contrast, 8% rescreened early (before 21 months) and 16% rescreened late (after 3 years).

Screening results

Risk refers to the risk for significant cervical abnormality, and is determined by the result of the Cervical Screening Test (CST)—comprised of an HPV test and, if indicated, reflex liquid based cytology (LBC). The risk allocated to the woman determines her recommendation. Women considered to be at low risk are recommended to rescreen in 5 years, women considered to be at intermediate risk are recommended to have a repeat HPV test in 12 months, and women considered to be at higher risk are referred for colposcopy.

Of the 1,523,868 primary screening episodes in 2018 in women aged 25–74:

  • 91% were low risk for significant cervical abnormality
  • 6% were intermediate risk for significant cervical abnormality
  • 3% were higher risk for significant cervical abnormality
  • fewer than 1% could not be assigned a risk (due to unsatisfactory or incomplete tests).

Screening HPV test positivity

All women who have a CST have an HPV test. This HPV test includes partial genotyping, which means that not only can it determine if a cancer-causing (oncogenic) HPV type is present, but it can further determine whether oncogenic HPV types 16 or 18 (the 2 types that cause most cervical cancers) are present. This means that the results of an HPV test will be one of ‘Oncogenic HPV not detected’, ‘Oncogenic HPV 16/18 detected’, ‘Oncogenic HPV (not 16/18) detected’, or ‘Unsatisfactory’

Screening HPV test positivity measures the proportion of primary screening HPV tests that detect oncogenic HPV. Of the 1,523,868 primary screening HPV tests performed in 2018 in women aged 25–74:

  • 2% were positive for oncogenic HPV types 16 or 18
  • 7% were positive for oncogenic HPV types other than 16 or 18.