Colonoscopies in Australia - how much does the National Bowel Cancer Screening Program contribute to colonoscopy use?

Objectives and importance of study: Colorectal cancer (CRC) is Australia's fourth most commonly diagnosed cancer. CRC screening is an effective intervention to reduce this burden. The National Bowel Cancer Screening Program (NBCSP) provides 2-yearly immunochemical faecal occult blood tests (iFOBTs) to Australians aged 50-74 years; a diagnostic colonoscopy is conducted after a positive iFOBT. Clinical guidelines inform colonoscopy usage, and appropriate use of these guidelines is vital to investigate gastrointestinal symptoms, detect bowel abnormalities and CRC, and remove precancerous polyps. Colonoscopy services are under strain, with limited formal strategies to prioritise patients. There are concerns among practitioners and patient advocates that the NBCSP generates additional colonoscopy requests and increases wait times, worsening patient outcomes and prolonging distress. In this research study, we estimate and project colonoscopy use in Australia from 2001 to 2030 and determine the impact of the NBCSP by examining model-estimated NBCSP colonoscopy demand. METHODS: Colonoscopy use in Australia was compiled using Medicare Benefits Schedule (MBS) claims for colonoscopies from 2001 to 2019. From these data, projections were made from 2020 to 2030. Policy1-Bowel, a microsimulation model, was used to estimate NBCSP-related colonoscopy demand from screening follow-up and colonoscopic surveillance from 2006 to 2030. RESULTS: MBS-funded colonoscopy use increased from 284 676 in 2001 to 663 213 in 2019. Annual use is projected to be more than 780 000 by 2030. Of these, 10-14% are projected to be generated by the NBCSP. Per-capita MBS-funded colonoscopy utilisation increased 0.2% annually over 2015-2019, a slowing of growth compared to previous trends. CONCLUSION: The NBCSP accounts for a modest fraction of colonoscopy use in Australia, and a better understanding of colonoscopy use not associated with the NBCSP is needed. Promoting adherence to guideline-recommended iFOBT and colonoscopy use could ease pressure on services and improve outcomes.

Changes in prostate cancer incidence, mortality and survival in relation to prostate specific antigen testing in New South Wales, Australia.

BACKGROUND: To examine changes in prostate cancer incidence and mortality rates, and 5-year relative survival, in relation to changes in the rate of prostate specific antigen (PSA) screening tests and the use of radical prostatectomy (RP) in the Australian population. METHODS: Prostate cancer stage-specific incidence rates, 5-year relative survival and mortality rates were estimated using New South Wales Cancer Registry data. PSA screening test rates and RP/Incidence ratios were estimated from Medicare Benefits Schedule claims data. We used multiple imputation to impute stage for cases with "unknown" stage at diagnosis. Annual percentage changes (APC) in rates were estimated using Joinpoint regression. RESULTS: Trends in the age-standardized incidence rates for localized disease largely mirrored the trends in PSA screening test rates, with a substantial 'spike' in the rates occurring in 1994, followed by a second 'spike' in 2008, and then a significant decrease from 2008 to 2015 (APC -6.7, 95% CI -8.2, -5.1). Increasing trends in incidence rates were observed for regional stage from the early 2000s, while decreasing or stable trends were observed for distant stage since 1993. The overall RP/Incidence ratio increased from 1998 to 2003 (APC 9.6, 95% CI 3.8, 15.6), then remained relatively stable to 2015. The overall 5-year relative survival for prostate cancer increased from 58.4% (95% CI: 55.0-61.7%) in 1981-1985 to 91.3% (95% CI: 90.5-92.1%) in 2011-2015. Prostate cancer mortality rates decreased from 1990 onwards (1990-2006: APC -1.7, 95% CI -2.1, -1.2; 2006-2017: APC -3.8, 95% CI -4.4, -3.1). CONCLUSIONS: Overall, there was a decrease in the incidence rate of localized prostate cancer after 2008, an increase in survival over time and a decrease in the mortality rate since the 1990s. This seems to indicate that the more conservative use of PSA screening tests in clinical practice since 2008 has not had a negative impact on population-wide prostate cancer outcomes.

Working towards a comprehensive understanding of HPV and cervical cancer among Indigenous women: a qualitative systematic review.

RATIONALE: Indigenous peoples carry a disproportionate burden of infectious diseases and cancers and are over-represented among the socially disadvantaged of most countries. Human papillomavirus (HPV) is a risk factor and causative agent of cervical, oropharyngeal and other cancers. Recent literature shows evidence of Indigenous populations being at increased risk of HPV infections and its associated cancers. OBJECTIVE: This is a qualitative systematic review. The objective of this study was to explore the experiences and barriers Indigenous women face in relation to HPV awareness, knowledge and cervical screening, in order to better understand factors that may mitigate against or facilitate prevention efforts for HPV infection and associated cancers. METHODS: Two investigators independently searched MEDLINE, PubMed, SCOPUS and Web of Science databases (for articles published from inception until 30 June 2020) using a prespecified search strategy to identify qualitative studies on narratives of Indigenous women regarding HPV infection awareness, knowledge and cervical screening, across all geographic and income-level settings. Using a 'meta-study' approach, a social ecological model of cervical screening, infection and associated cancer prevention among Indigenous populations was formulated. RESULTS: Five core themes were identified and formulated within the social ecological model; intrapersonal factors, interpersonal factors, institutional/organisational factors, sociocultural/community factors and public policy. These collectively formed the proposed social ecological model of HPV infection awareness and cervical cancer prevention among Indigenous women. This model has been synthesised by taking into account personal stories of Indigenous women and healthcare workers, thus offering a more nuanced, organised, structured and culturally sensitive approach to policy translation. CONCLUSION: The social ecological model of HPV infection awareness and cervical cancer prevention among Indigenous women offers a holistic and practical approach for Indigenous health policy makers. It clearly addresses the high risk of Indigenous populations at a global level in experience of both HPV infection and HPV-related cancers. PROSPERO REGISTRATION NUMBER: CRD42020207643.

Has Human Papillomavirus (HPV) Vaccination Prevented Adverse Pregnancy Outcomes? Population-Level Analysis After 8 Years of a National HPV Vaccination Program in Australia.

BACKGROUND: Human papillomavirus (HPV) infection, and its sequelae of precancerous cervical lesions and their subsequent treatment, have been linked with an increased risk of adverse pregnancy outcomes. Publicly funded HPV vaccination of female adolescents began in Australia in 2007 with initial catch-up to age 26 years. METHODS: Using data from the National Perinatal Data Collection we compared rates of preterm births and small-for-gestational-age infants born in Australia 2000-2015. We used generalized linear models, assuming a Poisson distribution and log link function, with single-year categories of infant birth year, maternal age, and age-specific HPV vaccination coverage as independent variables. RESULTS: In maternal cohorts with 60%-80% HPV vaccination coverage as achieved in Australia, there was a relative rate reduction of 3.2% (95% confidence interval, 1.1%-5.3%) in preterm births and 9.8% (8.2% to 11.4%) in small-for-gestational-age infants, after adjustment for infant's birth year and maternal age. CONCLUSION: This analysis provides provisional population-level evidence of a reduction in adverse pregnancy outcomes in cohorts of women offered HPV vaccination. Confounding by smoking or other variables and/or ecological analysis limitations, however, cannot be excluded. These findings indicate potential broader benefits of HPV vaccination than have been documented to date.

The combined impact of implementing HPV immunisation and primary HPV screening in New Zealand: Transitional and long-term benefits, costs and resource utilisation implications.

BACKGROUND: In response to emergent evidence, many countries are transitioning from cytology-based to HPV screening. We evaluated the impact of an upcoming transition on health outcomes and resource utilisation in New Zealand. METHODS: An extensively validated model of HPV transmission, vaccination, natural history and cervical screening ('Policy1-Cervix') was utilised to simulate a transition from three-yearly cytology for women 20-69 years to five-yearly HPV screening with 16/18 genotyping for women 25-69 years, accounting for population growth and the impact of HPV immunisation. Cervical cancer rates, resources use (test volumes), costs, and test positivity rates from 2015 to 2035 were estimated. FINDINGS: By 2035, the transition to HPV screening will result in declines in cervical cancer incidence and mortality rates by 32% and 25%, respectively, compared to 2018. A potentially detectable 5% increase in cervical cancer incidence due to earlier detection is predicted for the year of transition. Annual numbers of women screened will fluctuate with the five-year screening interval. Cytology volumes will reduce by over 80% but colposcopy volumes will be similar to pre-transition rates, and program costs will be reduced by 16%. A 9% HPV test positivity rate is expected in the first round of HPV screening (2019-2023), with 2.7% of women referred for colposcopy. Transitioning from cytology to primary HPV cervical screening could avert 149 cancer cases and 45 deaths by 2035. CONCLUSION: Primary HPV screening and vaccination will reduce cervical cancer and resources use. A small transient apparent increase of invasive cancer rates due to earlier detection may be detectable at the population level, reflecting the introduction of a more sensitive screening test. These findings can be used to inform health services planning and public communications surrounding program implementation.

Health services costs for cancer care in Australia: Estimates from the 45 and Up Study.

BACKGROUND: Cancer care represents a substantial and rapidly rising healthcare cost in Australia. Our aim was to provide accurate population-based estimates of the health services cost of cancer care using large-scale linked patient-level data. METHODS: We analysed data for incident cancers diagnosed 2006-2010 and followed to 2014 among 266,793 eligible participants in the 45 and Up Study. Health system costs included Medicare and pharmaceutical claims, inpatient hospital episodes and emergency department presentations. Costs for cancer cases and matched cancer-free controls were compared, to estimate monthly/annual excess costs of cancer care by cancer type, before and after diagnosis and by phase of care (initial, continuing, terminal). Total costs incurred in 2013 were also estimated for all people diagnosed in Australia 2009-2013. RESULTS: 7624 participants diagnosed with cancer were matched with up to three controls. The mean excess cost of care per case was AUD$1,622 for the year before diagnosis, $33,944 for the first year post-diagnosis and $8,796 for the second year post-diagnosis, with considerable variation by cancer type. Mean annual cost after the initial treatment phase was $4,474/case and the mean cost for the last year of life was $49,733/case. In 2013 the cost for cancers among people in Australia diagnosed during 2009-2013 was ~$6.3billion (0.4% of Gross Domestic Product; $272 per capita), with the largest costs for colorectal cancer ($1.1billion), breast cancer ($0.8billion), lung cancer ($0.6billion) and prostate cancer ($0.5billion). CONCLUSIONS: The cost of cancer care is substantial and varies by cancer type and time since diagnosis. These findings emphasise the economic importance of effective primary and secondary cancer prevention strategies.