Screening practices of Australian men and women categorized as "at or slightly above average risk" of colorectal cancer

Effects of health education on screening rate of first-degree relatives of cancer patients: A systematic review and meta-analysis

OBJECTIVE

To synthesize the effects of educational intervention on the screening rate of first-degree relatives of cancer patients.

METHODS

A total of eight Chinese and English databases were searched (PubMed, Embase, Cochrane Library, CINAHL, Web of Science, Scopus, Medline and China Biology Medicine disc) from the time of library establishment to June 2023, for randomized controlled trials investigating the effects of educational intervention on screening rate of first-degree relatives of cancer patients. Two researchers independently screened and evaluated the quality of studies. RevMan 5.3 software was used to calculate the pooled effect size.

RESULTS

Thirteen studies involving 5628 participants were chosen to include in the meta-analysis. The results revealed that health education can increase screening rate of first-degree relatives of cancer patients (RR = 1.39, 95% CI = 1.16-1.65, P = 0.0002). The effect shown after short-term follow-up (≤6 months) was insignificant in terms of improving screening rate (RR = 1.46, 95% CI = 0.94-2.26, P = 0.09), but after long-term follow-up (＞6 months) the improvement was greater (RR = 1.37, 95% CI = 1.13-1.65, P = 0.002).

CONCLUSION

Health education is effective in increasing the screening rate of first-degree relatives of cancer patients. The effect is more evident after long-term than short-term follow-up.

Potential global loss of life expected due to COVID-19 disruptions to organised colorectal cancer screening

Background

Screening for colorectal cancer (CRC) decreases cancer burden through removal of precancerous lesions and early detection of cancer. The COVID-19 pandemic has disrupted organised CRC screening programs worldwide, with some programs completely suspending screening and others experiencing significant decreases in participation and diagnostic follow-up. This study estimated the global impact of screening disruptions on CRC outcomes, and potential effects of catch-up screening.

Methods

Organised screening programs were identified in 29 countries, and data on participation rates and COVID-related changes to screening in 2020 were extracted where available. Four independent microsimulation models (ASCCA, MISCAN-Colon, OncoSim, and Policy1-Bowel) were used to estimate the long-term impact on CRC cases and deaths, based on decreases to screening participation in 2020. For countries where 2020 participation data were not available, changes to screening were approximated based on excess mortality rates. Catch-up strategies involving additional screening in 2021 were also simulated.

Findings

In countries for which direct data were available, organised CRC screening volumes at a country level decreased by an estimated 1.3-40.5% in 2020. Globally, it is estimated that COVID-related screening decreases led to a deficit of 7.4 million fewer faecal screens performed in 2020. In the absence of any organised catch-up screening, this would lead to an estimated 13,000 additional CRC cases and 7,900 deaths globally from 2020 to 2050; 79% of the additional cases and 85% of additional deaths could have been prevented with catch-up screening, respectively.

Interpretation

COVID-19-related disruptions to screening will cause excess CRC cases and deaths, but appropriately implemented catch-up screening could have reduced the burden by over 80%. Careful management of any disruption is key to improving the resilience of colorectal cancer screening programs.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by Cancer Council New South Wales, Health Canada, and Dutch National Institute for Public Health and Environment.

Exploring a novel method for optimising the implementation of a colorectal cancer risk prediction tool into primary care: a qualitative study

Background

We developed a colorectal cancer risk prediction tool (‘CRISP’) to provide individualised risk-based advice for colorectal cancer screening. Using known environmental, behavioural, and familial risk factors, CRISP was designed to facilitate tailored screening advice to patients aged 50 to 74 years in general practice. In parallel to a randomised controlled trial of the CRISP tool, we developed and evaluated an evidence-based implementation strategy.

Methods

Qualitative methods were used to explore the implementation of CRISP in general practice. Using one general practice in regional Victoria, Australia, as a ‘laboratory’, we tested ways to embed CRISP into routine clinical practice. General practitioners, nurses, and operations manager co-designed the implementation methods with researchers, focussing on existing practice processes that would be sustainable. Researchers interviewed the staff regularly to assess the successfulness of the strategies employed, and implementation methods were adapted throughout the study period in response to feedback from qualitative interviews.

The Consolidated Framework for Implementation Research (CFIR) underpinned the development of the interview guide and intervention strategy. Coding was inductive and themes were developed through consensus between the authors. Emerging themes were mapped onto the CFIR domains and a fidelity checklist was developed to ensure CRISP was being used as intended.

Results

Between December 2016 and September 2019, 1 interviews were conducted, both face-to-face and via videoconferencing (Zoom). All interviews were transcribed verbatim and coded. Themes were mapped onto the following CFIR domains: (1) ‘characteristics of the intervention’: CRISP was valued but time consuming; (2) ‘inner setting’: the practice was open to changing systems; 3. ‘outer setting’: CRISP helped facilitate screening; (4) ‘individual characteristics’: the practice staff were adaptable and able to facilitate adoption of new clinical processes; and (5) ‘processes’: fidelity checking, and education was important.

Conclusions

These results describe a novel method for exploring implementation strategies for a colorectal cancer risk prediction tool in the context of a parallel RCT testing clinical efficacy. The study identified successful and unsuccessful implementation strategies using an adaptive methodology over time. This method emphasised the importance of co-design input to make an intervention like CRISP sustainable for use in other practices and with other risk tools.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13012-022-01205-8.

Prevalence of skin examination behaviours among Australians over time

BACKGROUND

We aimed to examine the prevalence and correlates of opportunistic skin check behaviours among Australians and whether changes over time might explain increasing underlying rates of melanoma in situ.

METHODS

The National Sun Protection Survey involved periodic telephone-based cross-sectional surveys during summer since 2003. Skin checks by a doctor in the past 12 months was asked in four summers over 2006-2017, and responses from 23,374 Australians aged 12-69 years were analysed. Prevalence estimates were weighted to be representative of the Australian population. Chi-square tests compared the prevalence over time and by characteristics.

RESULTS

The overall proportion reporting whole-body skin checks in the past 12 months was 20 % in 2006-07 and 2010-11, 21 % in 2013-14, and 22 % in 2016-17; but increased from 29 % in 2006-07 to 37 % in 2016-17 for those aged 45-69 years (p < 0.0001). In 2016-17, 5% reported a skin check of part-body and 9% for a specific mole or spot. The proportion reporting no skin checks increased from 61 % to 64 % over time (p < 0.0001). Whole-body skin checks were more common among older respondents, females, and also varied by residence location, skin sensitivity, skin colour, risk perception, and socio-economic index (all p < 0.001).

CONCLUSION

Approximately one third of Australians had their skin checked by a doctor within a 12-month period, but this varied across population sub-groups. Skin check behaviours were relatively stable over time, with modest increases in the prevalence of skin checks for those aged 45-69 years. These findings do not explain underlying large increases in rates of melanoma in situ.

The CRISP-P study: feasibility of a self-completed colorectal cancer risk prediction tool in primary care

OBJECTIVE

Australia and New Zealand have the highest incidence of colorectal cancer (CRC) globally. Our research team has developed a CRC risk prediction tool for use in primary care to increase targeted screening. This study, Colorectal cancer RISk Prediction tool - patient ('CRISP-P'), aimed to determine the following to inform a future trial design: (i) the feasibility of self-reporting; (ii) the feasibility of recruitment methods; and (iii) the prevalence of CRC risk.

METHODS

Participants aged between 40 and 75 years were recruited consecutively from three primary care waiting rooms. Participants input data into CRISP on a tablet without receiving clinical advice. Feasibility was evaluated using recruitment rate, timely completion, a self-reported 'ease-of-use', score and field notes. Prevalence of CRC risk was calculated using the CRISP model.

RESULTS

Five hundred sixty-one (90%) patients agreed to use the tool and 424 (84%) rated the tool easy to use. Despite this, 41% of people were unable to complete the questions without assistance. Patients who were older, without tertiary education or with English as their second language were more likely to require assistance (P < 0.001). Thirty-nine percent of patients were low risk, 58% at slightly increased and 2.4% were at moderately increased risk of developing colorectal cancer in the next 5 years.

CONCLUSIONS

The tool was perceived as easy to use, although older, less educated people, and patients with English as their second language needed help. The data support the recruitment methods but not the use of a self-completed tool for an efficacy trial.

Costs and Cost-Effectiveness of Targeted, Personalized Risk Information to Increase Appropriate Screening by First-Degree Relatives of People With Colorectal Cancer

Background. Economic evaluations are less commonly applied to implementation interventions compared to clinical interventions. The efficacy of an implementation strategy to improve adherence to screening guidelines among first-degree relatives of people with colorectal cancer was recently evaluated in a randomized-controlled trial. Using these trial data, we examined the costs and cost-effectiveness of the intervention from societal and health care funder perspectives. Method. In this prospective, trial-based evaluation, mean costs, and outcomes were calculated. The primary outcome of the trial was the proportion of participants who had screening tests in the year following the intervention commensurate with their risk category. Quality-adjusted life years were included as secondary outcomes. Intervention costs were determined from trial records. Standard Australian unit costs for 2016/2017 were applied. Cost-effectiveness was assessed using the net benefit framework. Nonparametric bootstrapping was used to calculate uncertainty intervals (UIs) around the costs and the incremental net monetary benefit statistic. Results. Compared with usual care, mean health sector costs were $17 (95% UI [$14, $24]) higher for those receiving the intervention. The incremental cost-effectiveness ratio for the primary trial outcome was calculated to be $258 (95% UI [$184, $441]) per additional person appropriately screened. The significant difference in adherence to screening guidelines between the usual care and intervention groups did not translate into a mean quality-adjusted life year difference. Discussion. Providing information on both the costs and outcomes of implementation interventions is important to inform public health care investment decisions. Challenges in the application of cost-utility analysis hampered the interpretation of results and potentially underestimated the value of the intervention. Further research in the form of a modeled extrapolation of the intermediate increased adherence effect and distributional cost-effectiveness to include equity requirements is warranted.

Family history-based colorectal cancer screening in Australia: A modelling study of the costs, benefits, and harms of different participation scenarios

BACKGROUND

The Australian National Bowel Cancer Screening Programme (NBCSP) was introduced in 2006. When fully implemented, the programme will invite people aged 50 to 74 to complete an immunochemical faecal occult blood test (iFOBT) every 2 years.

METHODS AND FINDINGS

To investigate colorectal cancer (CRC) screening occurring outside of the NBCSP, we classified participants (n = 2,480) in the Australasian Colorectal Cancer Family Registry (ACCFR) into 3 risk categories (average, moderately increased, and potentially high) based on CRC family history and assessed their screening practices according to national guidelines. We developed a microsimulation to compare hypothetical screening scenarios (70% and 100% uptake) to current participation levels (baseline) and evaluated clinical outcomes and cost for each risk category. The 2 main limitations of this study are as follows: first, the fact that our cost-effectiveness analysis was performed from a third-party payer perspective, which does not include indirect costs and results in overestimated cost-effectiveness ratios, and second, that our natural history model of CRC does not include polyp sojourn time, which determines the rate of cancerous transformation. Screening uptake was low across all family history risk categories (64%-56% reported no screening). For participants at average risk, 18% reported overscreening, while 37% of those in the highest risk categories screened according to guidelines. Higher screening levels would substantially reduce CRC mortality across all risk categories (95 to 305 fewer deaths per 100,000 persons in the 70% scenario versus baseline). For those at average risk, a fully implemented NBCSP represented the most cost-effective approach to prevent CRC deaths (AUS$13,000-16,000 per quality-adjusted life year [QALY]). For those at moderately increased risk, higher adherence to recommended screening was also highly cost-effective (AUS$19,000-24,000 per QALY).

CONCLUSION

Investing in public health strategies to increase adherence to appropriate CRC screening will save lives and deliver high value for money.

The use of a risk assessment and decision support tool (CRISP) compared with usual care in general practice to increase risk-stratified colorectal cancer screening: study protocol for a randomised controlled trial

BACKGROUND

Australia and New Zealand have the highest incidence rates of colorectal cancer worldwide. In Australia there is significant unwarranted variation in colorectal cancer screening due to low uptake of the immunochemical faecal occult blood test, poor identification of individuals at increased risk of colorectal cancer, and over-referral of individuals at average risk for colonoscopy. Our pre-trial research has developed a novel Colorectal cancer RISk Prediction (CRISP) tool, which could be used to implement precision screening in primary care. This paper describes the protocol for a phase II multi-site individually randomised controlled trial of the CRISP tool in primary care.

METHODS

This trial aims to test whether a standardised consultation using the CRISP tool in general practice (the CRISP intervention) increases risk-appropriate colorectal cancer screening compared to control participants who receive standardised information on cancer prevention. Patients between 50 and 74 years old, attending an appointment with their general practitioner for any reason, will be invited into the trial. A total of 732 participants will be randomised to intervention or control arms using a computer-generated allocation sequence stratified by general practice. The primary outcome (risk-appropriate screening at 12 months) will be measured using baseline data for colorectal cancer risk and objective health service data to measure screening behaviour. Secondary outcomes will include participant cancer risk perception, anxiety, cancer worry, screening intentions and health service utilisation measured at 1, 6 and 12 months post randomisation.

DISCUSSION

This trial tests a systematic approach to implementing risk-stratified colorectal cancer screening in primary care, based on an individual's absolute risk, using a state-of-the-art risk assessment tool. Trial results will be reported in 2020.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trial Registry, ACTRN12616001573448p . Registered on 14 November 2016.

Prevalence of appropriate colorectal cancer screening and preferences for receiving screening advice among people attending outpatient clinics

OBJECTIVE

To examine among people attending outpatient clinics aged 50-74 at average risk of colorectal cancer (CRC): 1) The proportion who report: a) faecal occult blood test (FOBT) within the past two years; and b) colonoscopy within the past five years, including the reasons for undergoing colonoscopy; 2) characteristics associated with under-screening; 3) For those who are under-screened, the proportion who are: a) willing to receive help and the acceptability of different methods of receiving help, and; b) unwilling to receive help and reasons for this.

METHODS

Cross-sectional survey of 197 participants attending a major regional hospital in New South Wales, Australia. Multivariable logistic regression was used to determine correlates of under-screening.

RESULTS

A total of 59% reported either FOBT in the past two years or colonoscopy in the past five years. Of those reporting colonoscopy in the past five years, 21% were potentially over-screened. Males were more likely than females to be under-screened. Of those under-screened (41%), fewer than half were willing to receive screening advice. Conclusions and implications for public health: A significant proportion of people attending outpatient clinics are under-screened for CRC, with some people also over-screened. There is a need to explore strategies to overcome both under- and over-screening.

Faecal occult blood testing (FOBT)-based colorectal cancer screening trends and predictors of non-use: findings from the South Australian setting and implications for increasing FOBT uptake

Objective The present study used data from three South Australian population health surveys to examine trends in knowledge, recent use and reasons for use or non-use of faecal occult blood testing (FOBT) for colorectal cancer (CRC) screening from 2011 to 2014. Screening awareness and demographic factors related to non-use were also examined. Methods FOBT trends were examined for respondents aged 50–75 years across survey years (n ~ 1000). Logistic regression analyses were undertaken to determine predictors of non-use and reasons for non-use of FOBT based on latest data. Results The proportion of respondents reporting recent FOBT use has trended up, whereas the proportion reporting non-use has trended down. Awareness of screening recommendations has increased. Respondents who were aware of screening recommendations and those aged 65–69 years were significantly less likely to report non-use. The most commonly reported reasons for FOBT use were as part the national screening program or routine examination, whereas reasons for non-use were not having symptoms and doctor not advising to have the test. Conclusions FOBT screening trends are indicative of the positive effect of the continued expansion of the national screening program. FOBT uptake may be increased by addressing salient barriers, as indicated by persisting reasons for non-use of FOBT. What is known about the topic? Australia has one of the highest age-standardised incidence rates of CRC (or bowel cancer) in the world. Population screening using non-invasive stool-based FOBT was implemented in Australia in 2006 with the introduction of the National Bowel Cancer Screening Program (NBCSP). To date, the NBCSP has been extended to only a small proportion of the target population and FOBT screening rates remain well below desired levels to effect changes in CRC outcomes at the population level. There is a recognised need for more robust data on CRC screening practices to inform interventions aimed at increasing FOBT uptake, beyond the scope of the NBCSP. What does this paper add? The study provides valuable insights into trends of FOBT screening indicators over time in the South Australia, drawing on data from population state health surveys undertaken from 2011 to 2014. A particular advantage of the dataset was that it included data on reasons for use and non-use of FOBT. These data are not routinely assessed in population-level studies of FOBT uptake, although such information would be beneficial for tracking implementation of the national program and identifying salient barriers to FOBT uptake in low-participation groups. Thus, the study also describes factors related to non-use and reasons for non-use of FOBT among the target population for CRC screening. What are the implications for practitioners? Results suggest that there have been considerable shifts in community knowledge and FOBT screening participation rates from 2011 to 2014, reflecting the positive effect of the NBCSP. Reliance on physician recommendation to screen, as well as knowledge deficits related to screening frequency and the perceived relevance of screening remain prominent barriers to FOBT uptake. Recommendations for increasing FOBT uptake are made in view of salient barriers and identified segments of the population less likely to report FOBT use.

The CRISP colorectal cancer risk prediction tool: an exploratory study using simulated consultations in Australian primary care

Background

In Australia, screening for colorectal cancer (CRC) with colonoscopy is meant to be reserved for people at increased risk, however, currently there is a mismatch between individuals’ risk of CRC and the type of CRC screening they receive.

This paper describes the development and optimisation of a Colorectal cancer RISk Prediction tool (‘CRISP’) for use in primary care. The aim of the CRISP tool is to increase risk-appropriate CRC screening.

Methods

CRISP development was informed by previous experience with developing risk tools for use in primary care and a systematic review of the evidence. A CRISP prototype was used in simulated consultations by general practitioners (GPs) with actors as patients. GPs were interviewed to explore their experience of using CRISP, and practice nurses (PNs) and practice managers (PMs) were interviewed after a demonstration of CRISP. Transcribed interviews and video footage of the ‘consultations’ were qualitatively analyzed. Themes arising from the data were mapped onto Normalization Process Theory (NPT).

Results

Fourteen GPs, nine PNs and six PMs were recruited from 12 clinics. Results were described using the four constructs of NPT: 1) Coherence: Clinicians understood the rationale behind CRISP, particularly since they were familiar with using risk tools for other conditions; 2) Cognitive participation: GPs welcomed the opportunity CRISP provided to discuss healthy and unhealthy behaviors with their patients, but many GPs challenged the screening recommendation generated by CRISP; 3) Collective Action: CRISP disrupted clinician-patient flow if the GP was less comfortable with computers. GP consultation time was a major implementation barrier and overall consensus was that PNs have more capacity and time to use CRISP effectively; 4) Reflexive monitoring: Limited systematic monitoring of new interventions is a potential barrier to the sustainable embedding of CRISP.

Conclusions

CRISP has the potential to improve risk-appropriate CRC screening in primary care but was considered more likely to be successfully implemented as a nurse-led intervention.

Can a print-based intervention increase screening for first degree relatives of people with colorectal cancer? A randomised controlled trial

Objective: To test the effectiveness of a targeted print‐based intervention to improve screening adherence in first degree relatives of people with colorectal cancer (CRC).

Methods: People with CRC and their adult first degree relatives were identified through a population‐based cancer registry and randomly allocated as a family unit to the intervention or control condition. The control group received general information about CRC screening. The intervention group received printed advice regarding screening that was targeted to their risk level. Screening adherence was assessed at baseline and at 12 months via self report.

Results: 752 (25%) index cases and 574 (34%) eligible first degree relatives consented to take part in the trial and completed baseline interviews. At 12 months, 58% of first degree relatives in the control group and 61% in the intervention group were adherent to screening guidelines (mixed effects logistic regression group by time interaction effect =2.7; 95%CI=1.2–5.9; P=0.013). Subgroup analysis indicated that the intervention was only effective for those with the lowest risk.

Conclusions: Provision of personalised risk information may have a modest effect on adherence to CRC screening recommendations among first degree relatives of people diagnosed with CRC.

Implications: Improved strategies for identifying and engaging first degree relatives are needed to maximise the population impact of the intervention.

Colorectal cancer screening in the familial risk population: Is colonoscopy still the strategy of choice?

First-degree relatives of patients with colorectal cancer (CRC) are at high risk of this disease. For this reason, medical organizations and clinical guidelines recommend more intensive screening and surveillance for such first-degree relatives than for the average-risk population. Colonoscopy has been the cornerstone of CRC screening in this setting. Although colonoscopy is the most sensitive technique for the detection of neoplastic lesions (especially non-advanced adenomas), its role is less clear for CRC. In addition, screening colonoscopy has several limitations that may affect the success of a screening campaign, such as poor participant acceptance, the need for skilled endoscopists, participant access to screening colonoscopy, overburdened endoscopy units, potential complications, and procedure-related costs. In addition, recent evidence has cast doubt on the advantage of colonoscopy over other strategies for the detection of advanced neoplastic lesions. Despite being less sensitive in general, other screening methods frequently recommended in the average-risk population may be more acceptable and thus help increase CRC screening uptake. This review discusses recent evidence on the risk of CRC in first-degree relatives, the advantages and disadvantages of each screening technique, participation rates depending on the technique, patient preferences, and barriers to screening.

Colorectal cancer screening

Colorectal cancer is one of the most common malignancies in Australia, and screening to detect it an earlier stage is cost-effective. Furthermore, detection and removal of precursor polyps can reduce incidence. Currently, there are limited data to determine the screening rate in Australia, but it is certainly lower than the 80% screening rate considered desirable. Whether colonoscopy is used as the screening test or to follow up positive results of an initial non-invasive test, it plays a fundamental role. Despite high sensitivity and specificity, it is expensive and invasive with measurable risk and is not acceptable as an initial test to many participants. It does not provide complete protection, and interval cancers between planned colonoscopies are associated with proximal location, origin in sessile serrated adenomas and operator-dependent factors. An essential component of colorectal screening is the measurement of colonoscopy quality indicators, such as caecal intubation and adenoma detection rates, which are known to be associated with the rate of interval cancer. The non-invasive screening test currently recommended in Australia is biennial testing for faecal occult blood between the ages of 50 and 75 using a faecal immunochemical test, with positives evaluated by colonoscopy. This is provided through the National Bowel Cancer Screening Programme, currently for those at the ages of 50, 55, 60 and 65 years, with full implementation of biennial screening by 2020. To improve screening in Australia, the most fruitful approach may be to acknowledge that there is a choice of screening tests and to focus on the goal of improving overall participation rate and being able to measure this.

Equivalency of fecal immunochemical tests and colonoscopy in familial colorectal cancer screening

BACKGROUND & AIMS

Colonoscopy is the recommended screening procedure for first-degree relatives of patients with colorectal cancer (CRC), but few studies have compared its efficacy for CRC detection with that of other screening strategies. We conducted a controlled randomized trial to compare the efficacy of repeated fecal immunochemical tests (FITs) and colonoscopy in detecting advanced neoplasia (advanced adenoma or CRC) in family members of patients with CRC.

METHODS

In a prospective study, 1918 first-degree relatives of patients with CRC were randomly assigned (1:1 ratio) to receive a single colonoscopy examination or 3 FITs (1/year for 3 years; OC-Sensor; cutoff ≥10 μg hemoglobin/g feces, corresponding to 50 ng hemoglobin/mL buffer). The strategies were considered to be equivalent if the 95% confidence interval of the difference for the detection of advanced neoplasia was ±3%. Follow-up analyses were performed to identify false-negative FIT results and interval CRCs.

RESULTS

Of all eligible asymptomatic first-degree relatives, 782 were included in the colonoscopy group and 784 in the FIT group. In the intention-to-screen analysis, advanced neoplasia was detected in 33 (4.2%) and 44 (5.6%) first-degree relatives in the FIT and colonoscopy groups, respectively (odds ratio = 1.41; 95% confidence interval: 0.88-2.26; P = .14). In the per-protocol analysis, 28 first-degree relatives (3.9%) in the FIT group and 43 (5.8%) in the colonoscopy group had advanced neoplasia (odds ratio = 1.56; 95% confidence interval: 0.95-2.56; P = .08). FIT missed 16 of 41 advanced adenomas but no CRCs. The FIT strategy required endoscopic evaluation of 4-fold fewer individuals to detect 1 advanced neoplasia than the colonoscopy strategy.

CONCLUSIONS

Repeated FIT screening (1/year for 3 years) detected all CRCs and proved equivalent to colonoscopy in detecting advanced neoplasia in first-degree relatives of patients with CRC. This strategy should be considered for populations where compliance with FITs is higher than with colonoscopy. ClinicalTrials.gov number: NCT01075633 (COLONFAM Study).

Cost-effectiveness of family history-based colorectal cancer screening in Australia

Background

With 14.234 diagnoses and over 4047 deaths reported in 2007, colorectal cancer (CRC) is the second most common cancer and second most common cause of cancer-related mortality in Australia. The direct treatment cost has recently been estimated to be around AU$1.2 billion for the year 2011, which corresponds to a four-fold increase, compared the cost reported in 2001. Excluding CRCs due to known rare genetic disorders, 20% to 25% of all CRCs occur in a familial aggregation setting due to genetic variants or shared environmental risk factors that are yet to be characterised. A targeted screening strategy addressed to this segment of the population is a potentially valuable tool for reducing the overall burden of CRC.

Methods

We developed a Markov model to assess the cost-effectiveness of three screening strategies offered to people at increased risk due to a strong family history of CRC. The model simulated the evolution of a cohort of 10,000 individuals from age 50 to 90 years. We compared screening with biennial iFOBT, five-yearly colonoscopy and ten-yearly colonoscopy versus the current strategy of the Australian National Bowel Cancer Screening Programme (i.e. base case).

Results

Under the NBCSP scenario, 6,491 persons developed CRC with an average screening lifetime cost of AU$3,441 per person. In comparison, screening with biennial iFOBT, colonoscopy every ten years, and colonoscopy every five years reduced CRC incidence by 27%, 35% and 60%, and mortality by 15%, 26% and 46% respectively. All three screening strategies had a cost under AU$50,000 per life year gained, which is regarded as the upper limit of acceptable cost-effectiveness in the Australian health system. At AU$12,405 per life year gained and an average lifetime expectancy of 16.084 years, five-yearly colonoscopy screening was the most cost-effective strategy.

Conclusion

The model demonstrates that intensive CRC screening strategies targeting people at increased risk would be cost-effective in the Australian context. Our findings provide evidence that substantial health benefits can be generated from risk-based CRC screening at a relatively modest incremental cost.