Colorectal cancer screening in Australia
Authors: Ernst J Kuipers, Iris Lansdorp-Vogelaar
Journal: The Lancet Public Health (2017)

Colorectal cancer is among the most common causes of cancer-related mortality. Between 1990 and 2013, global colorectal cancer-related mortality increased from 490 000 to 771 000 per annum.1GBD 2013 Mortality and Causes of Death CollaboratorsGlobal, regional, and national age–sex specific all-cause and cause-specific mortality for 240 causes of death, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013.Lancet. 2015; 385: 117-171Summary Full Text Full Text PDF PubMed Scopus (5368) Google Scholar Our failure to systematically reduce incidence and mortality is remarkable because colorectal cancer is more fitted for population screening and prevention than any other malignancy. It has a long preclinical stage with treatable precursors, adenomatous, and serrated polyps.2Kuipers EJ Grady WM Lieberman D et al.Colorectal cancer.Nat Rev Dis Prim. 2015; 1: 15065Crossref PubMed Scopus (834) Google Scholar Polyp removal and treatment of early cancer improve disease outcome. The array of screening instruments continues to expand. The effect of screening on incidence and mortality has been extensively shown.3Kuipers EJ Rösch T Bretthauer M Colorectal cancer screening—optimizing current strategies and new directions.Nat Rev Clin Oncol. 2013; 10: 130-142Crossref PubMed Scopus (152) Google Scholar Screening can be cost saving due to high disease incidence, low costs of some screening methods, and high costs of treatment for advanced cancer. The slow implementation of population screening in most countries relates to various issues that might differ per region.4Schreuders EH Ruco A Rabeneck L et al.Colorectal cancer screening: a global overview of existing programmes.Gut. 2015; 64: 1637-1649Crossref PubMed Scopus (715) Google Scholar Effective screening requires political support, provision of information to the target population, resources, training of health professionals, and quality assurance. Effective implementation of population screening that is optimally adapted to any local situation can thus take many years. In the Netherlands for instance, 16 years were needed from initial preparation of pilot studies in 2002 to completed roll-out of a national screening programme in 2018.5Toes-Zoutendijk E van Leerdam ME Dekker E et al.real-time monitoring of results during first year of Dutch colorectal cancer screening program and optimization by altering fecal immunochemical test cut-off levels.Gastroenterology. 2017; 152: 767-775Summary Full Text Full Text PDF PubMed Scopus (142) Google Scholar With many potential screening strategies, among others varying in primary screening method, age range, and screening interval, it is very difficult to evaluate all options in practice in any individual country. This underscores the value of decision models. These models simulate a population over time and allow assessment of the effect of different screening strategies.6Kuntz KM Lansdorp-Vogelaar I Rutter CM et al.A systematic comparison of microsimulation models of colorectal cancer: the role of assumptions about adenoma progression.Med Decis Mak. 2011; 31: 530-539Crossref PubMed Scopus (82) Google Scholar In The Lancet Public Health, Jie-Bin Lew and colleagues7Lew JB St John JB Xu XM et al.Long-term evaluation of benefits, harms, and cost-effectiveness of the National Bowel Cancer Screening Program in Australia: a modelling study.Lancet Public Health. 2017; (published online June 26.)http://dx.doi.org/10.1016/S2468-2667(17)30105-6Google Scholar modelled the future impact of the Australian colorectal cancer screening programme on disease incidence and mortality.7Lew JB St John JB Xu XM et al.Long-term evaluation of benefits, harms, and cost-effectiveness of the National Bowel Cancer Screening Program in Australia: a modelling study.Lancet Public Health. 2017; (published online June 26.)http://dx.doi.org/10.1016/S2468-2667(17)30105-6Google Scholar The programme consists of biennial faecal immunochemical testing (FIT) of 50–74 year-old participants followed by colonoscopy in case of a haemoglobin concentration higher than 20 μg/g in the faeces.7Lew JB St John JB Xu XM et al.Long-term evaluation of benefits, harms, and cost-effectiveness of the National Bowel Cancer Screening Program in Australia: a modelling study.Lancet Public Health. 2017; (published online June 26.)http://dx.doi.org/10.1016/S2468-2667(17)30105-6Google Scholar The programme started in 2006, with slow roll-out despite an incidence of colorectal cancer among the highest in the world. Single-round participation is now 39%, and 70% of screenees with a positive FIT receive further assessment.8Australian Institute of Health and WelfareNational bowel cancer screening program. Monitoring report.http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129559632Date: 2017Google Scholar The authors calculated that screening with 40% participation will prevent 92 200 cancer cases and 59 000 deaths until 2040, and is highly cost effective. The authors also modelled other scenarios at different levels of participation. The forecasts under different scenarios are helpful, not only for Australia but also for other countries contemplating such a programme. Lew and colleagues' study7Lew JB St John JB Xu XM et al.Long-term evaluation of benefits, harms, and cost-effectiveness of the National Bowel Cancer Screening Program in Australia: a modelling study.Lancet Public Health. 2017; (published online June 26.)http://dx.doi.org/10.1016/S2468-2667(17)30105-6Google Scholar provides important support for the further roll-out and continuation of the programme. This is a key message for the Australian population, politicians, and health-care providers. Despite its preventive effect, the model predicts that screening at the current participation level will not bring the number of colorectal cancer diagnoses and deaths per annum below current numbers. This should stimulate Australian public health professionals to find means to increase participation, which currently is lower compared with other colorectal cancer screening programmes and internationally accepted targets.9Ponti A Anttilla A Ronco G et al.Cancer screening in the European Union. Report on the implementation of the Council recommendation on cancer screening.https://ec.europa.eu/health/sites/health/files/major_chronic_diseases/docs/2017_cancerscreening_2ndreportimplementation_en.pdfDate: 2017Google Scholar Indeed, the USA aim for 80% screening coverage of the target population by 2018, while European guidelines recommend an uptake of at least 65%.10von Karsa L Patnick J et al.European Colorectal Cancer Screening Guidelines Working GroupEuropean guidelines for quality assurance in colorectal cancer screening and diagnosis: Overview and introduction to the full Supplement publication.Endoscopy. 2012; 45: 51-59Crossref PubMed Scopus (390) Google Scholar The study findings should also stimulate to reduce the current 30% failure rate to assess individuals with a positive FIT.8Australian Institute of Health and WelfareNational bowel cancer screening program. Monitoring report.http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129559632Date: 2017Google Scholar Similar issues are encountered elsewhere, which underlines the relevance to share best practices.4Schreuders EH Ruco A Rabeneck L et al.Colorectal cancer screening: a global overview of existing programmes.Gut. 2015; 64: 1637-1649Crossref PubMed Scopus (715) Google Scholar Apart from these strengths, the study also has some limitations. Decision models are based on a range of assumptions regarding progression of neoplasia, efficacy, and costs of treatment, and screening accuracy and impact. Realistic predictions thus ask for extensive validation of the model against data from long-term prospective randomised screening trials, like has been done for other models.6Kuntz KM Lansdorp-Vogelaar I Rutter CM et al.A systematic comparison of microsimulation models of colorectal cancer: the role of assumptions about adenoma progression.Med Decis Mak. 2011; 31: 530-539Crossref PubMed Scopus (82) Google Scholar, 11Rutter CM Knudsen AB Marsh TL et al.Validation of models used to inform colorectal cancer screening guidelines.Med Decis Mak. 2016; 36: 604-614Crossref PubMed Scopus (40) Google Scholar The decision model in this study seemed to lack this validation for the impact of screening.7Lew JB St John JB Xu XM et al.Long-term evaluation of benefits, harms, and cost-effectiveness of the National Bowel Cancer Screening Program in Australia: a modelling study.Lancet Public Health. 2017; (published online June 26.)http://dx.doi.org/10.1016/S2468-2667(17)30105-6Google Scholar The predictions that screening can reduce colorectal cancer incidence and mortality, as well as reduce costs, are widely supported. But the magnitude of effect might differ. The model used by Lew and colleagues7Lew JB St John JB Xu XM et al.Long-term evaluation of benefits, harms, and cost-effectiveness of the National Bowel Cancer Screening Program in Australia: a modelling study.Lancet Public Health. 2017; (published online June 26.)http://dx.doi.org/10.1016/S2468-2667(17)30105-6Google Scholar predicts that FIT screening with 60% participation might reduce overall colorectal cancer mortality with 40–45%, whereas available studies do not find a mortality reduction of more than 40% even if all eligible individuals in the population participate.12Giorgi Rossi P Vicentini M Sacchettini C et al.Impact of screening program on incidence of colorectal cancer: a cohort study in Italy.Am J Gastroenterol. 2015; 110: 1359-1366Crossref PubMed Scopus (93) Google Scholar Despite this limitation, we applaud Australia for monitoring and evaluating their cancer screening programme. These studies improve and optimise cancer screening,5Toes-Zoutendijk E van Leerdam ME Dekker E et al.real-time monitoring of results during first year of Dutch colorectal cancer screening program and optimization by altering fecal immunochemical test cut-off levels.Gastroenterology. 2017; 152: 767-775Summary Full Text Full Text PDF PubMed Scopus (142) Google Scholar yet they are nevertheless lacking in most countries. In an effort to build capacity for such monitoring and evaluation, the Horizon 2020 funded EU-TOPIA project was launched, which will provide countries across Europe access to validated web-based monitoring and modelling instruments. In conclusion, Australia has high colorectal cancer incidence and mortality. The number of cancer cases and deaths would, without intervention, certainly further increase in the coming two decades. FIT screening can halt this increase, and save costs. It is therefore important that the roll-out of the FIT programme continues, and that measures are taken to increase its participation as well as assessment of screenees with a positive FIT. Policy makers and health-care providers should next look at additional interventions to further improve the impact of screening, for instance by lowering FIT cut-off. For more on the EU-TOPIA project see eu-topia.org For more on the EU-TOPIA project see eu-topia.org We declare no competing interests. IL-V is funded by the EUTOPIA project (H2020-PHC-2014 No. 634753). Long-term evaluation of benefits, harms, and cost-effectiveness of the National Bowel Cancer Screening Program in Australia: a modelling studyThe NBCSP has potential to save 83 800 lives over the period 2015–40 if coverage rates can be increased to 60%. By contrast, the associated harms, although an important consideration, are at a smaller magnitude at the population level. The programme is highly cost-effective and within a decade of full roll-out, there will be reduced annual health systems expenditure on colorectal cancer control due to the impact of screening. Full-Text PDF Open Access