But cervical cancer death rates are low thanks to early screening, and the proportion of squamous cell carcinomas has dropped drastically.
One in 10 HPV screening tests come back positive for a type that causes cervical cancer, according to the latest figures from the National Cervical Screening Program.
But the incidence of cervical cancer and mortality was low in the five years to 2022, at 11 new cases and two deaths per 100,000 women in the general population.
This reflects the success of the cervical cancer screening program, which has halved cervical cancer incidence and mortality since 1991, the Australian Institute of Health and Welfare said.
The latest data showed that for every 1000 participants screened in 2022, 14 had a high-grade abnormality detected by histology, and one had a cervical cancer detected.
“This reflects that the aim of cervical screening is not to detect cervical cancer, but to prevent it through the detection of high-grade abnormalities,” the AIHW said.
It’s the AIHW’s fifth report since the cervical screening program changed in 2017 from two-yearly Pap tests to five-yearly HPV screening, to be followed by a liquid-based cytology (LBC) tests if oncogenic HPV was found.
In those five years, more than 4.7 million participants aged 25 to 74 had a primary screening or 12-month repeat HPV test – a participation rate of 68% of the eligible population.
In 2022, the CST data showed only 2% of the results were positive for HPV 16 or 18, while 8% were positive for oncogenic HPV (non 16/18).
The 2021 figures also showed that 63% of participants aged 25 to 74 at higher risk of a significant cervical abnormality had a colposcopy within three months, and the median time to colposcopy was 56 days.
But for Aboriginal and Torres Strait Islander women at higher risk of a significant cervical abnormality, only 51% had a colposcopy within three months.
After analysing data on the histological subtypes of cervical cancer, the AIHW said squamous cell carcinomas now made up only 60% of cervical cancers, down from the “historical proportion” of 95%.
“The [National Cervical Screening Program] has been successful in preventing squamous cell carcinomas by detecting high-grade squamous abnormalities, these being readily identified by repeated cervical cytology.”
Adenocarcinomas now made up 29% of all cervical cancers because there were fewer squamous cell carcinomas, and adenocarcinomas had not been reduced by cervical screening at the same rate, the AIHW said.
Over the five-year period, women aged 25 to 29 had the highest participation rate at 80%, while the lowest rate was 35% among participants aged 70 to 74.
In addition, women living in socioeconomically disadvantaged areas were found to be more likely to die from cervical cancer.
Between 2017 and 2021, mortality was 3.5 per 100,000 women in the most socioeconomically disadvantaged areas, compared with 1.2 in areas of highest socioeconomic advantage.
And the incidence of cervical cancer among Aboriginal and Torres Strait Islander women was 2.1 times the rate of non-Indigenous women, while mortality was 3.5 times higher.
Participants living in remote areas were also found to be less likely to take part in screening. Participation in the screening program was lowest in very remote areas, where just 59% of people took part in screening compared to 70% in major cities.
The AIHW said it anticipated future reductions in the incidence of cervical cancer, thanks to the national HPV vaccination program and the renewed national cervical screening program.
“Australia is set to become the first country in the world to actively eliminate cervical cancer, with modelling predicting that the incidence of cervical cancer will drop to fewer than four new cases per 100,000 women by 2035, and to fewer than one new case per 100,000 women by 2066.”
But cervical screening remains a vital secondary prevention strategy even for people who have been HPV-vaccinated as well as those who are unvaccinated.
“It is important that all eligible people participate in cervical screening, irrespective of their HPV vaccination status.”
Earlier data from the Australian Institute of Health and Welfare showed that 72% of cervical cancers diagnosed between 2002 and 2012 in women aged 20 to 69 were in women who had never been screened or had been late with their screening.
“This research further showed that cervical cancers that did occur in recently screened women were less likely to cause death than those diagnosed in women who had never screened, which is likely due to these cancers being detected at an earlier stage.”
