Evaluation of the benefits, harms and cost-effectiveness of potential alternatives to iFOBT testing for colorectal cancer screening in Australia

Early colorectal cancer screening–no time to lose

In this editorial, we comment on the article entitled “Stage at diagnosis of colorectal cancer through diagnostic route: Who should be screened?” by Agatsuma et al. Colorectal cancer (CRC) is emerging as an important health issue as its incidence continues to rise globally, adversely affecting the quality of life. Although the public has become more aware of CRC prevention, most patients lack screening awareness. Some poor lifestyle practices can lead to CRC and symptoms can appear in the early stages of CRC. However, due to the lack of awareness of the disease, most of the CRC patients are diagnosed already at an advanced stage and have a poor prognosis.

SMARTERscreen protocol: a three-arm cluster randomised controlled trial of patient SMS messaging in general practice to increase participation in the Australian National Bowel Cancer Screening Program

BACKGROUND

Australia persistently has one of the highest rates of colorectal cancer (CRC) in the world. Australia's National Bowel Cancer Screening Program (NBCSP) sends a biennial Faecal Immunochemical Test (FIT)-the 'NBCSP kit'-to everyone eligible for the programme between 50 and 74 years old; however, participation in the programme is low, especially in the 50- to 60-year-old age group. Our previous efficacy trial ('SMARTscreen') demonstrated an absolute increase in uptake of 16.5% (95% confidence interval = 2.02-30.9%) for people sent an SMS with motivational and instructional videos, from their general practice prior to receiving their NBCSP kit, compared to those receiving usual care. Building on the strengths of the SMARTscreen trial and addressing limitations, the 'SMARTERscreen' trial will test the effect on participation in the NBCSP of sending either an SMS only or an SMS with online video material to general practice patients due to receive their NBCSP compared to 'usual care'.

METHODS

SMARTERscreen is a three-arm stratified cluster randomised controlled trial involving 63 general practices in two states in Australia. Eligible patients are patients who are aged 49-60 years and due to receive their NBCSP kit within the next 2 weeks during the intervention period. General practices will be equally randomised to three trial arms (21:21:21, estimated average 260 patients/practice). The two interventions include (i) an SMS with an encouraging message from their general practice or (ii) the same SMS with weblinks to additional motivational and instructional videos. The control arm will receive 'usual care'. Using the intention-to-treat approach, primary analysis will estimate the three pair-wise between-arm differences in the proportion of eligible patients who participate in the NBCSP within 6 months of when their kit is sent, utilising screening data from the Australian National Cancer Screening Register (NCSR). Patient intervention adherence to the interventions will also be evaluated. Findings will be incorporated into the Policy1-Bowel microsimulation model to estimate the long-term health benefits and cost-effectiveness of the interventions.

DISCUSSION

SMARTERscreen will provide high-level evidence determining whether an SMS or an SMS with web-based material sent to general practice patients prior to receiving their NBCSP kit increases participation in bowel cancer screening.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12623000036617. Registered on 13 January 2023. Trial URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=385119&isClinicalTrial=False.

Is there a place for sigmoidoscopy in colorectal cancer screening? A systematic review and critical appraisal of cost-effectiveness models

INTRODUCTION

Screening for colorectal cancer (CRC) is effective in reducing both incidence and mortality. Colonoscopy and stool tests are most frequently used for this purpose. Sigmoidoscopy is an alternative screening measure with a strong evidence base. Due to its distinct characteristics, it might be preferred by subgroups. The aim of this systematic review is to analyze the cost-effectiveness of sigmoidoscopy for CRC screening compared to other screening methods and to identify influencing parameters.

METHODS

A systematic literature search for the time frame 01/2010-01/2023 was conducted using the databases MEDLINE, Embase, EconLit, Web of Science, NHS EED, as well as the Cost-Effectiveness Registry. Full economic analyses examining sigmoidoscopy as a screening measure for the general population at average risk for CRC were included. Incremental cost-effectiveness ratios were calculated. All included studies were critically assessed based on a questionnaire for modelling studies.

RESULTS

Twenty-five studies are included in the review. Compared to no screening, sigmoidoscopy is a cost-effective screening strategy for CRC. When modelled as a single measure strategy, sigmoidoscopy is mostly dominated by colonoscopy or modern stool tests. When combined with annual stool testing, sigmoidoscopy in 5-year intervals is more effective and less costly than the respective strategies alone. The results of the studies are influenced by varying assumptions on adherence, costs, and test characteristics.

CONCLUSION

The combination of sigmoidoscopy and stool testing represents a cost-effective screening strategy that has not received much attention in current guidelines. Further research is needed that goes beyond a narrow focus on screening technology and models different, preference-based participation behavior in subgroups.

Geographical and spatial variations in bowel cancer screening participation, Australia, 2015-2020

BACKGROUND

Participation in bowel cancer screening programs remains poor in many countries. Knowledge of geographical variation in participation rates may help design targeted interventions to improve uptake. This study describes small-area and broad geographical patterns in bowel screening participation in Australia between 2015-2020.

METHODS

Publicly available population-level participation data for Australia's National Bowel Cancer Screening Program (NBCSP) were modelled using generalized linear models to quantify screening patterns by remoteness and area-level disadvantage. Bayesian spatial models were used to obtain smoothed estimates of participation across 2,247 small areas during 2019-2020 compared to the national average, and during 2015-2016 and 2017-2018 for comparison. Spatial heterogeneity was assessed using the maximized excess events test.

RESULTS

Overall, screening participation rates was around 44% over the three time-periods. Participation was consistently lower in remote or disadvantaged areas, although heterogeneity was evident within these broad categories. There was strong evidence of spatial differences in participation over all three periods, with little change in patterns between time periods. If the spatial variation was reduced (so low participation areas were increased to the 80th centile), an extra 250,000 screens (4% of total) would have been conducted during 2019-2020.

CONCLUSIONS

Despite having a well-structured evidence-based government funded national bowel cancer screening program, the substantial spatial variation in participation rates highlights the importance of accounting for the unique characteristics of specific geographical regions and their inhabitants. Identifying the reasons for geographical disparities could inform interventions to achieve more equitable access and a higher overall bowel screening uptake.

Effectiveness of Colorectal Cancer (CRC) Screening on All-Cause and CRC-Specific Mortality Reduction: A Systematic Review and Meta-Analysis

(1) Background: The aim of this study was to pool and compare all-cause and colorectal cancer (CRC) specific mortality reduction of CRC screening in randomized control trials (RCTs) and simulation models, and to determine factors that influence screening effectiveness. (2) Methods: PubMed, Embase, Web of Science and Cochrane library were searched for eligible studies. Multi-use simulation models or RCTs that compared the mortality of CRC screening with no screening in general population were included. CRC-specific and all-cause mortality rate ratios and 95% confidence intervals were calculated by a bivariate random model. (3) Results: 10 RCTs and 47 model studies were retrieved. The pooled CRC-specific mortality rate ratios in RCTs were 0.88 (0.80, 0.96) and 0.76 (0.68, 0.84) for guaiac-based fecal occult blood tests (gFOBT) and single flexible sigmoidoscopy (FS) screening, respectively. For the model studies, the rate ratios were 0.45 (0.39, 0.51) for biennial fecal immunochemical tests (FIT), 0.31 (0.28, 0.34) for biennial gFOBT, 0.61 (0.53, 0.72) for single FS, 0.27 (0.21, 0.35) for 10-yearly colonoscopy, and 0.35 (0.29, 0.42) for 5-yearly FS. The CRC-specific mortality reduction of gFOBT increased with higher adherence in both studies (RCT: 0.78 (0.68, 0.89) vs. 0.92 (0.87, 0.98), model: 0.30 (0.28, 0.33) vs. 0.92 (0.51, 1.63)). Model studies showed a 0.62-1.1% all-cause mortality reduction with single FS screening. (4) Conclusions: Based on RCTs and model studies, biennial FIT/gFOBT, single and 5-yearly FS, and 10-yearly colonoscopy screening significantly reduces CRC-specific mortality. The model estimates are much higher than in RCTs, because the simulated biennial gFOBT assumes higher adherence. The effectiveness of screening increases at younger screening initiation ages and higher adherences.

Colon and rectal cancer treatment patterns and their associations with clinical, sociodemographic and lifestyle characteristics: analysis of the Australian 45 and Up Study cohort

BACKGROUND

Colorectal cancer is the third most diagnosed cancer globally and the second leading cause of cancer death. We examined colon and rectal cancer treatment patterns in Australia.

METHODS

From cancer registry records, we identified 1,236 and 542 people with incident colon and rectal cancer, respectively, diagnosed during 2006-2013 in the 45 and Up Study cohort (267,357 participants). Cancer treatment and deaths were determined via linkage to routinely collected data, including hospital and medical services records. For colon cancer, we examined treatment categories of "surgery only", "surgery plus chemotherapy", "other treatment" (i.e. other combinations of surgery/chemotherapy/radiotherapy), "no record of cancer-related treatment, died"; and, for rectal cancer, "surgery only", "surgery plus chemotherapy and/or radiotherapy", "other treatment", and "no record of cancer-related treatment, died". We analysed survival, time to first treatment, and characteristics associated with treatment receipt using competing risks regression.

RESULTS

86.4% and 86.5% of people with colon and rectal cancer, respectively, had a record of receiving any treatment ≤2 years post-diagnosis. Of those treated, 93.2% and 90.8% started treatment ≤2 months post-diagnosis, respectively. Characteristics significantly associated with treatment receipt were similar for colon and rectal cancer, with strongest associations for spread of disease and age at diagnosis (p<0.003). For colon cancer, the rate of "no record of cancer-related treatment, died" was higher for people with distant spread of disease (versus localised, subdistribution hazard ratio (SHR)=13.6, 95% confidence interval (CI):5.5-33.9), age ≥75 years (versus age 45-74, SHR=3.6, 95%CI:1.8-7.1), and visiting an emergency department ≤1 month pre-diagnosis (SHR=2.9, 95%CI:1.6-5.2). For rectal cancer, the rate of "surgery plus chemotherapy and/or radiotherapy" was higher for people with regional spread of disease (versus localised, SHR=5.2, 95%CI:3.6-7.7) and lower for people with poorer physical functioning (SHR=0.5, 95%CI:0.3-0.8) or no private health insurance (SHR=0.7, 95%CI:0.5-0.9).

CONCLUSION

Before the COVID-19 pandemic, most people with colon or rectal cancer received treatment ≤2 months post-diagnosis, however, treatment patterns varied by spread of disease and age. This work can be used to inform future healthcare requirements, to estimate the impact of cancer control interventions to improve prevention and early diagnosis, and serve as a benchmark to assess treatment delays/disruptions during the pandemic. Future work should examine associations with clinical factors (e.g. performance status at diagnosis) and interdependencies between characteristics such as age, comorbidities, and emergency department visits.

A systematic analysis of the global and regional burden of colon and rectum cancer and the difference between early- and late-onset CRC from 1990 to 2019

The burden of colorectal cancer (CRC) varies substantially across different geographical locations. However, there was no further quantitative analysis of regional social development and the disease burden of CRC. In addition, the incidence of early- and late-onset CRC has increased rapidly in developed and developing regions. The main purpose of this study was to investigate the trends in CRC burden across different regions, in addition to the epidemiological differences between early and late-onset CRC and their risk factors. In this study, estimated annual percentage change (EAPC) was employed to quantify trends in age-standardized incidence rate (ASIR), mortality rate, and disability-adjusted life-years. Restricted cubic spline models were fitted to quantitatively analyze the relationship between trends in ASIR and Human Development Index (HDI). In addition, the epidemiological characteristics of early- and late-onset CRC were investigated using analyses stratified by age groups and regions. Specifically, meat consumption and antibiotic use were included to explore the differences in the risk factors for early- and late-onset CRC. The quantitative analysis showed that the ASIR of CRC was exponentially and positively correlated with the 2019 HDI in different regions. In addition, the growing trend of ASIR in recent years varied substantially across HDI regions. Specifically, the ASIR of CRC showed a significant increase in developing countries, while it remained stable or decreased in developed countries. Moreover, a linear correlation was found between the ASIR of CRC and meat consumption in different regions, especially in developing countries. Furthermore, a similar correlation was found between the ASIR and antibiotic use in all age groups, with different correlation coefficients for early-onset and late-onset CRC. It is worth mentioning that the early onset of CRC could be attributable to the unrestrained use of antibiotics among young people in developed countries. In summary, for better prevention and control of CRC, governments should pay attention to advocate self-testing and hospital visits among all age groups, especially among young people at high risk of CRC, and strictly control meat consumption and the usage of antibiotics.

Cost-Effectiveness of Colorectal Cancer Surveillance in Hodgkin Lymphoma Survivors Treated with Procarbazine and/or Infradiaphragmatic Radiotherapy

BACKGROUND

Hodgkin lymphoma survivors treated with infradiaphragmatic radiotherapy (IRT) and/or procarbazine have an increased risk of developing colorectal cancer. We investigated the cost-effectiveness of colorectal cancer surveillance in Dutch Hodgkin lymphoma survivors to determine the optimal surveillance strategy for different Hodgkin lymphoma subgroups.

METHODS

The Microsimulation Screening Analysis-Colon model was adjusted to reflect colorectal cancer and other-cause mortality risk in Hodgkin lymphoma survivors. Ninety colorectal cancer surveillance strategies were evaluated varying in starting and stopping age, interval, and modality [colonoscopy, fecal immunochemical test (FIT, OC-Sensor; cutoffs: 10/20/47 μg Hb/g feces), and multi-target stool DNA test (Cologuard)]. Analyses were also stratified per primary treatment (IRT and procarbazine or procarbazine without IRT). Colorectal cancer deaths averted (compared with no surveillance) and incremental cost-effectiveness ratios (ICER) were primary outcomes. The optimal surveillance strategy was identified assuming a willingness-to-pay threshold of €20,000 per life-years gained (LYG).

RESULTS

Overall, the optimal surveillance strategy was annual FIT (47 μg) from age 45 to 70 years, which might avert 70% of colorectal cancer deaths in Hodgkin lymphoma survivors (compared with no surveillance; ICER:€18,000/LYG). The optimal surveillance strategy in Hodgkin lymphoma survivors treated with procarbazine without IRT was biennial FIT (47 μg) from age 45 to 70 years (colorectal cancer mortality averted 56%; ICER:€15,000/LYG), and when treated with IRT and procarbazine, annual FIT (47 μg) surveillance from age 40 to 70 was most cost-effective (colorectal cancer mortality averted 75%; ICER:€13,000/LYG).

CONCLUSIONS

Colorectal cancer surveillance in Hodgkin lymphoma survivors is cost-effective and should commence earlier than screening occurs in population screening programs. For all subgroups, FIT surveillance was the most cost-effective strategy.

IMPACT

Colorectal cancer surveillance should be implemented in Hodgkin lymphoma survivors.

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.

Characteristics of patients aged 50-74 years with a request for an immunochemical faecal occult blood test in the Australian general practice setting

ObjectiveTo support improving participation in the National Bowel Cancer Screening Program (NBCSP), we aimed to identify Medicare-subsidised test requests for immunochemical faecal occult blood tests (FOBT) in Australian general practice for patients aged 50-74 years, eligible for the NBCSP, and describe sociodemographics, risk factors, indications and outcomes.MethodsA cross-sectional study was conducted using de-identified data from 441 Australian general practice sites in the MedicineInsight database, recorded from 1 January 2018 to 31 December 2019.ResultsOf the 683 625 eligible patients, 45 771 (6.7%) had a record of a general practitioner (GP)-requested FOBT, either to aid diagnosis in symptomatic patients, or for screening; 144 986 (21.2%) patients had only an NBCSP FOBT. A diagnosis of polyps, gastrointestinal inflammatory condition or haemorrhoids, or a referral to a gastroenterologist or general surgeon, was more commonly recorded in the 6 months after a GP-requested FOBT than after an NBCSP FOBT. Uptake of NBCSP FOBTs was lower among those with obesity, high alcohol consumption and current smokers, who are at higher risk of bowel cancer.ConclusionsThis study describes the patient characteristics, reasons and outcomes associated with GP-requested FOBTs, identifies under-screened population sub-groups, and suggests involvement of GPs to improve participation in the NBCSP.

The SMARTscreen Trial: a randomised controlled trial investigating the efficacy of a GP-endorsed narrative SMS to increase participation in the Australian National Bowel Cancer Screening Program

BACKGROUND

Increasing participation in the Australian National Bowel Cancer Screening Program (NBCSP) is the most efficient and cost-effective way of reducing mortality associated with colorectal cancer by detecting and treating early-stage disease. Currently, only 44% of Australians aged 50-74 years complete the NBCSP. This efficacy trial aims to test whether this SMS intervention is an effective method for increasing participation in the NBCSP. Furthermore, a process evaluation will explore the barriers and facilitators to sending the SMS from general practice.

METHODS

We will recruit 20 general practices in the western region of Victoria, Australia to participate in a cluster randomised controlled trial. General practices will be randomly allocated with a 1:1 ratio to either a control or intervention group. Established general practice software will be used to identify patients aged 50 to 60 years old who are due to receive a NBCSP kit in the next month. The SMS intervention includes GP endorsement and links to narrative messages about the benefits of and instructions on how to complete the NBCSP kit. It will be sent from intervention general practices to eligible patients prior to receiving the NBCSP kit. We require 1400 eligible patients to provide 80% power with a two-sided 5% significance level to detect a 10% increase in CRC screening participation in the intervention group compared to the control group. Our primary outcome is the difference in the proportion of eligible patients who completed a faecal occult blood test (FOBT) between the intervention and control group for up to 12 months after the SMS was sent, as recorded in their electronic medical record (EMR). A process evaluation using interview data collected from general practice staff (GP, practice managers, nurses) and patients will explore the feasibility and acceptability of sending and receiving a SMS to prompt completing a NBCSP kit.

DISCUSSION

This efficacy trial will provide initial trial evidence of the utility of an SMS narrative intervention to increase participation in the NBCSP. The results will inform decisions about the need for and design of a larger, multi-state trial of this SMS intervention to determine its cost-effectiveness and future implementation.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12620001020976 . Registered on 17 October 2020.

Cancer screening simulation models: a state of the art review

Background

Nowadays, various simulation approaches for evaluation and decision making in cancer screening can be found in the literature. This paper presents an overview of approaches used to assess screening programs for breast, lung, colorectal, prostate, and cervical cancers. Our main objectives are to describe methodological approaches and trends for different cancer sites and study populations, and to evaluate quality of cancer screening simulation studies.

Methods

A systematic literature search was performed in Medline, Web of Science, and Scopus databases. The search time frame was limited to 1999–2018 and 7101 studies were found. Of them, 621 studies met inclusion criteria, and 587 full-texts were retrieved, with 300 of the studies chosen for analysis. Finally, 263 full texts were used in the analysis (37 were excluded during the analysis). A descriptive and trend analysis of models was performed using a checklist created for the study.

Results

Currently, the most common methodological approaches in modeling cancer screening were individual-level Markov models (34% of the publications) and cohort-level Markov models (41%). The most commonly evaluated cancer types were breast (25%) and colorectal (24%) cancer. Studies on cervical cancer evaluated screening and vaccination (18%) or screening only (13%). Most studies have been conducted for North American (42%) and European (39%) populations. The number of studies with high quality scores increased over time.

Conclusions

Our findings suggest that future directions for cancer screening modelling include individual-level Markov models complemented by screening trial data, and further effort in model validation and data openness.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12911-021-01713-5.

Health system costs and days in hospital for colorectal cancer patients in New South Wales, Australia

Introduction

Colorectal cancer (CRC) care costs the Australian healthcare system more than any other cancer. We estimated costs and days in hospital for CRC cases, stratified by site (colon/rectal cancer) and disease stage, to inform detailed analyses of CRC-related healthcare.

Methods

Incident CRC patients were identified using the Australian 45 and Up Study cohort linked with cancer registry records. We analysed linked hospital admission records, emergency department records, and reimbursement records for government-subsidised medical services and prescription medicines. Cases’ health system costs (2020 Australian dollars) and hospital days were compared with those for cancer-free controls (matched by age, sex, geography, smoking) to estimate excess resources by phase of care, analysed by sociodemographic, health, and disease characteristics.

Results

1200 colon and 546 rectal cancer cases were diagnosed 2006–2013, and followed up to June 2016. Eighty-nine percent of cases had surgery, chemotherapy or radiotherapy, and excess costs were predominantly for hospitalisations. Initial phase (12 months post-diagnosis) mean excess health system costs were $50,434 for colon and $60,877 for rectal cancer cases, with means of 16 and 18.5 excess hospital days, respectively. The annual continuing mean excess costs were $6,779 (colon) and $8,336 (rectal), with a mean of 2 excess hospital days each. Resources utilised (costs and days) in these phases increased with more advanced disease, comorbidities, and younger age. Mean excess costs in the year before death were $74,952 (colon) and $67,733 (rectal), with means of 34 and 30 excess hospital days, respectively–resources utilised were similar across all characteristics, apart from lower costs for cases aged ≥75 at diagnosis.

Conclusions

Health system costs and hospital utilisation for CRC care are greater for people with more advanced disease. These findings provide a benchmark, and will help inform future cost-effectiveness analyses of potential approaches to CRC screening and treatment.

Cost-effectiveness analysis of a community-based colorectal cancer screening program in Shanghai, China

OBJECTIVE

This study investigated the cost-effectiveness of a community-based colorectal cancer-screening program (C-CRCSP) in Shanghai, China, among the residents in the urban, suburban and rural areas.

METHODS

A Markov model was constructed to evaluate the cost-effectiveness of a 25-year annual C-CRCSP including 100 000 populations. Cost-effectiveness was determined by the incremental cost-effectiveness ratio (ICER); referring to either life-years gained, or quality-adjusted life-years (QALYs) gained. The threshold was gross domestic product per capita. Univariate and multivariate sensitivity analyses were performed to investigate the influence of compliance, prevalence, technological performance, medical cost and annual cost discount rate (3.5%) on ICER. A probabilistic sensitivity analysis evaluated the probability of the cost-effectiveness of C-CRCSP at different maximum acceptable ceiling ratios.

RESULTS

Compared with no screening, the C-CRCSP resulted in total gains of 7840 QALYs and 2210 life-years (LY), at a total cost of CNY 58.54 million; that is, the ICER were CNY 7460/QALYs and CNY 26650/LY. Stratifying by residency, the cumulative gains in QALYs and LY were estimated to be the lowest in the urban populations compared with the rural and suburban populations. The cost for the urban population was 3-fold and 6-fold that of the suburban and rural populations. The ICER for QALYs ranged from 2180 (rural) to 16 840 (urban).

CONCLUSION

The cost-effectiveness of a C-CRCSP in Shanghai was most favorable for the rural population, while the urban population benefits less in terms of QALYs. ICER could be enhanced by measures that increase compliance.

Coprocytobiology: A Technical Review of Cytological Colorectal Cancer Screening in Fecal Samples

GRAPHICAL ABSTRACT

Cost-effectiveness analysis of alternative colorectal cancer screening strategies in high-risk individuals

BACKGROUND AND AIMS

Current guidelines recommend colonoscopy every 3-5 years for colorectal cancer (CRC) screening of individuals with a familial history of CRC. The objective of this study was to compare the cost effectiveness of screening alternatives in this population.

METHODS

Eight screening strategies were compared with no screening: fecal immunochemical test (FIT), Stool DNA and blood-based screening every 2 years, colonoscopy, computed tomography colonography, colon capsules, and sigmoidoscopy every 5 years, and colonoscopy at 45 years followed, if negative, by FIT every 2 years. Screening test and procedures performance were obtained from the literature. A microsimulation model reproducing the natural history of CRC was used to estimate the cost (€2018) and effectiveness [quality-adjusted life-years (QALYs)] of each strategy. A lifetime horizon was used. Costs and effectiveness were discounted at 3.5% annually.

RESULTS

Compared with no screening, colonoscopy and sigmoidoscopy at a 30% uptake were the most effective strategy (46.3 and 43.9 QALY/1000). FIT at a 30 µg/g threshold with 30% uptake was only half as effective (25.7 QALY). Colonoscopy was associated with a cost of €484,000 per 1000 individuals whereas sigmoidoscopy and FIT were associated with much lower costs (€123,610 and €66,860). Incremental cost-effectiveness rate for FIT and sigmoidoscopy were €2600/QALY (versus no screening) and €3100/QALY (versus FIT), respectively, whereas it was €150,000/QALY for colonoscopy (versus sigmoidoscopy). With a lower threshold (10 µg/g) and a higher uptake of 45%, FIT was more effective and less costly than colonoscopy at a 30% uptake and was associated with an incremental cost-effectiveness ratio (ICER) of €4240/QALY versus no screening.

CONCLUSION

At 30% uptake, current screening is the most effective screening strategy for high-risk individuals but is associated with a high ICER. Sigmoidoscopy and FIT at lower thresholds (10 µg/g) and a higher uptake should be given consideration as cost-effective alternatives.

PLAIN LANGUAGE SUMMARY

Cost-effectiveness analysis of colorectal cancer screening strategies in high-risk individuals Fecal occult blood testing with an immunochemical test (FIT) is generally considered as the most cost-effective alternative in colorectal cancer screening programs for average risk individuals without family history.Current screening guidelines for high-risk individuals with familial history recommend colonoscopy every 3-5 years.Colonoscopy every 3-5 years for individuals with familial history is the most effective strategy but is associated with a high incremental cost-effectiveness ratio.Compared with colonoscopy, if screening based on FIT is associated with a higher participation rate, it can achieve a similar effectiveness at a lower cost.

Large-scale systematic analysis of exposure to multiple cancer risk factors and the associations between exposure patterns and cancer incidence

Exposures to cancer risk factors such as smoking and alcohol are not mutually independent. We aimed to identify risk factor exposure patterns and their associations with sociodemographic characteristics and cancer incidence. We considered 120,771 female and, separately, 100,891 male participants of the Australian prospective cohort 45 and Up Study. Factor analysis grouped 36 self-reported variables into 8 combined factors each for females (largely representing 'smoking', 'alcohol', 'vigorous exercise', 'age at childbirth', 'Menopausal Hormone Therapy', 'parity and breastfeeding', 'standing/sitting', 'fruit and vegetables') and males (largely representing 'smoking', 'alcohol', 'vigorous exercise', 'urology and health', 'moderate exercise', 'standing/sitting', 'fruit and vegetables', 'meat and BMI'). Associations with cancer incidence were investigated using multivariable logistic regression (4-8 years follow-up: 6193 females, 8749 males diagnosed with cancer). After multiple-testing correction, we identified 10 associations between combined factors and cancer incidence for females and 6 for males, of which 14 represent well-known relationships (e.g. bowel cancer: females 'smoking' factor Odds Ratio (OR) 1.16 (95% Confidence Interval (CI) 1.08-1.25), males 'smoking' factor OR 1.15 (95% CI 1.07-1.23)), providing evidence for the validity of this approach. The catalogue of associations between exposure patterns, sociodemographic characteristics, and cancer incidence can help inform design of future studies and targeted prevention programmes.

Harms and Benefits of Cancer Screening

In recommending and offering screening, health services make a health claim ('it's good for you'). This article considers ethical aspects of establishing the case for cancer screening, building a service programme, monitoring its operation, improving its quality and integrating it with medical progress. The value of (first) screening is derived as a function of key parameters: prevalence of the target lesion in the detectable pre-clinical phase, the validity of the test and the respective net utilities or values attributed to four health states-true positives, false positives, false negatives and true negatives. Decision makers as diverse as public regulatory agencies, medical associations, health insurance funds or individual screenees can legitimately come up with different values even when presented with the same evidence base. The main intended benefit of screening is the reduction of cause-specific mortality. All-cause mortality is not measurably affected. Overdiagnosis and false-positive tests with their sequelae are the main harms. Harms and benefits accrue to distinct individuals. Hence the health claim is an invitation to a lottery with benefits for few and harms to many, a violation of the non-maleficence principle. While a public decision maker may still propose a justified screening programme, respect for individual rights and values requires preference-sensitive, autonomy-enhancing educational materials-even at the expense of programme effectiveness. Opt-in recommendations and more 'consumer-oriented' qualitative research are needed.

Cost-effectiveness analysis of alternative colon cancer screening strategies in the context of the French national screening program

BACKGROUND

A nationwide colorectal cancer (CRC) screening program was set up in France from 2009 for average-risk, asymptomatic people aged 50-74 years based on an immunochemical fecal occult blood test [faecal immunochemical test (FIT)] every 2 years, followed by colonoscopy if positive. The European standard recommends a participation rate of 45% for the program to be cost-effective, yet the latest published rate in France was 34%. The objective of this study was to compare the cost effectiveness of screening alternatives taking real-world participation rates into account.

METHODS

Eight screening strategies were compared, based either on a screening test (Guaiac or FIT testing, blood-based, stool DNA, computed tomography colonography, colon capsules, and sigmoidoscopy) followed by full colonoscopy if positive or direct colonoscopy. A microsimulation model was used to estimate the cost effectiveness associated with each strategy.

RESULTS

Compared with no screening, FIT was associated with a 14.0 quality-adjusted life year (QALY) increase of €50,520 per 1000 individuals, giving an incremental cost-effectiveness ratio (ICER) of €3600/QALY. Only stool DNA and blood-based testing were associated with a QALY increase compared with FIT, with stool DNA weakly dominated by blood-based testing, and the latter associated with an ICER of €154,600/QALY compared with FIT. All other strategies were dominated by FIT.

CONCLUSION

FIT every 2 years appears to be the most cost-effective CRC screening strategy when taking into account a real-world participation rate of 34%.

Validation of Microsimulation Models against Alternative Model Predictions and Long-Term Colorectal Cancer Incidence and Mortality Outcomes of Randomized Controlled Trials

Background. This study aimed to assess the validity of 2 microsimulation models of colorectal cancer (CRC), Policy1-Bowel and ASCCA. Methods. The model-estimated CRC risk in population subgroups with different health statuses, "dwell time" (time from incident precancerous polyp to symptomatically detected CRC), and reduction in symptomatically detected CRC incidence after a one-time complete removal of polyps and/or undetected CRC were compared with published findings from 3 well-established models (MISCAN, CRC-SPIN, and SimCRC). Furthermore, 6 randomized controlled trials (RCTs) that provided screening using a guaiac fecal occult blood test (Funen trial, Burgundy trial, and Minnesota Colon Cancer Control Study [MCCCS]) or flexible sigmoidoscopy (NORCCAP, SCORE, and UKFSST) with long-term follow-up were simulated. Model-estimated long-term relative reductions of CRC incidence (RR_inc) and mortality (RR_mort) were compared with the RCTs' findings. Results. The Policy1-Bowel and ASCCA estimates showed more similarities to CRC-SPIN and SimCRC. For example, overall dwell times estimated by Policy1-Bowel (24.0 years) and ASCCA (25.3) were comparable to CRC-SPIN (25.8) and SimCRC (25.2) but higher than MISCAN (10.6). In addition, ∼86% of Policy1-Bowel's and ∼74% of ASCCA's estimated RR_inc and RR_mort were consistent with the RCTs' long-term follow-up findings. For example, at 17 to 18 years of follow-up, the MCCCS reported RR_mort of 0.67 (95% confidence interval [CI], 0.51-0.83) and 0.79 (95% CI, 0.62-0.97) for the annual and biennial screening arm, respectively, and the UKFSST reported RR_mort of 0.70 (95% CI, 0.62-0.79) for CRC at all sites and 0.54 (95% CI, 0.46-0.65) for distal CRC. The corresponding model estimates were 0.65, 0.74, 0.81, and 0.61, respectively, for Policy1-Bowel and 0.65, 0.70, 0.75, and 0.58, respectively, for ASCCA. Conclusion. Policy1-Bowel and ASCCA's estimates are largely consistent with the data included for comparisons, which indicates good model validity.

Pathways to a cancer-free future: a protocol for modelled evaluations to minimise the future burden of colorectal cancer in Australia

INTRODUCTION

With almost 50% of cases preventable and the Australian National Bowel Cancer Screening Program in place, colorectal cancer (CRC) is a prime candidate for investment to reduce the cancer burden. The challenge is determining effective ways to reduce morbidity and mortality and their implementation through policy and practice. Pathways-Bowel is a multistage programme that aims to identify best-value investment in CRC control by integrating expert and end-user engagement; relevant evidence; modelled interventions to guide future investment; and policy-driven implementation of interventions using evidence-based methods. METHODS AND ANALYSIS: Pathways-Bowel is an iterative work programme incorporating a calibrated and validated CRC natural history model for Australia (Policy1-Bowel) and assessing the health and cost outcomes and resource use of targeted interventions. Experts help identify and prioritise modelled evaluations of changing trends and interventions and critically assess results to advise on their real-world applicability. Where appropriate the results are used to support public policy change and make the case for optimal investment in specific CRC control interventions. Fourteen high-priority evaluations have been modelled or planned, including evaluations of CRC outcomes from the changing prevalence of modifiable exposures, including smoking and body fatness; potential benefits of daily aspirin intake as chemoprevention; increasing CRC incidence in people aged <50 years; increasing screening participation in the general and Aboriginal and Torres Strait Islander populations; alternative screening technologies and modalities; and changes to follow-up surveillance protocols. Pathways-Bowel is a unique, comprehensive approach to evaluating CRC control; no prior body of work has assessed the relative benefits of a variety of interventions across CRC development and progression to produce a list of best-value investments.

ETHICS AND DISSEMINATION

Ethics approval was not required as human participants were not involved. Findings are reported in a series of papers in peer-reviewed journals and presented at fora to engage the community and policymakers.

Efficacy and cost-effectiveness of fecal immunochemical test versus colonoscopy in colorectal cancer screening: a systematic review and meta-analysis

BACKGROUND AND AIMS

The fecal immunochemical test (FIT) and colonoscopy are the most commonly used strategies for colorectal cancer (CRC) screening worldwide. We aimed to compare their efficacy and cost-effectiveness in CRC screening in an average-risk population.

METHODS

PubMed, Embase, and National Health Services Economic Evaluation Database were searched. Risk ratio (RR) was used to evaluate the differences in detection rates of colorectal neoplasia between FIT and colonoscopy groups. A random-effects model was used to pool RRs. Incremental cost-effectiveness ratios (ICERs) were calculated to evaluate the cost-effectiveness of FIT versus colonoscopy.

RESULTS

Six randomized controlled trials and 17 cost-effectiveness studies were included. The participation rate in the FIT group was higher than that in the colonoscopy group (41.6% vs 21.9%). In the intention-to-treat analysis, FIT had a detection rate of CRC comparable with colonoscopy (RR, .73; 95% confidence interval, .37-1.42) and lower detection rates of any adenoma and advanced adenoma than 1-time colonoscopy. Most included cost-effectiveness studies showed that annual (13/15) or biennial (5/6) FIT was cost-saving (ICER < $0) or very cost-effective ($0 < ICER ≤ $25000/quality-adjusted life-year) compared with colonoscopy every 10 years.

CONCLUSIONS

FIT may be similar to 1-time colonoscopy in the detection rate of CRC, although it has lower detection rates of any adenoma and advanced adenoma than 1-time colonoscopy. Furthermore, annual or biennial FIT appears to be very cost-effective or cost-saving compared with colonoscopy every 10 years. These findings indicate, at least partly, that FIT is noninferior to colonoscopy in CRC screening in an average-risk population. Our findings should be treated with caution and need to be further confirmed.

Improving Australian National Bowel Cancer Screening Program outcomes through increased participation and cost-effective investment

BACKGROUND

The Australian National Bowel Cancer Screening Program (NBCSP) provides biennial immunochemical faecal occult blood test (iFOBT) screening for people aged 50-74 years. Previous work has quantified the number of colorectal cancer (CRC) deaths prevented by the NBCSP and has shown that it is cost-effective. With a 40% screening participation rate, the NBCSP is currently underutilised and could be improved by increasing program participation, but the maximum appropriate level of spending on effective interventions to increase adherence has not yet been quantified.

OBJECTIVES

To estimate (i) reductions in CRC cases and deaths for 2020-2040 attributable to, and (ii) the threshold for cost-effective investment (TCEI) in, effective future interventions to improve participation in the NBCSP.

METHODS

A comprehensive microsimulation model, Policy1-Bowel, was used to simulate CRC natural history and screening in Australia, considering currently reported NBCSP adherence rates, i.e. iFOBT participation (∼40%) and diagnostic colonoscopy assessment rates (∼70%). Australian residents aged 40-74 were modelled. We evaluated three scenarios: (1) diagnostic colonoscopy assessment increasing to 90%; (2) iFOBT screening participation increasing to 60% by 2020, 70% by 2030 with diagnostic assessment rates of 90%; and (3) iFOBT screening increasing to 90% by 2020 with diagnostic assessment rates of 90%. In each scenario, we estimated CRC incidence and mortality, colonoscopies, costs, and TCEI given indicative willingness-to-pay thresholds of AUD$10,000-$30,000/LYS.

RESULTS

By 2040, age-standardised CRC incidence and mortality rates could be reduced from 46.2 and 13.5 per 100,000 persons, respectively, if current participation rates continued, to (1) 44.0 and 12.7, (2) 36.8 and 8.8, and (3) 31.9 and 6.5. In Scenario 2, 23,000 lives would be saved from 2020-2040 vs current participation rates. The estimated scenario-specific TCEI (Australian dollars or AUD$/year) to invest in interventions to increase participation, given a conservative willingness-to-pay threshold of AUD$10,000/LYS, was (1) AUD$14.9M, (2) AUD$72.0M, and (3) AUD$76.5M.

CONCLUSION

Significant investment in evidence-based interventions could be used to improve NBCSP adherence and help realise the program's potential. Such interventions might include mass media campaigns to increase program participation, educational or awareness interventions for practitioners, and/or interventions resulting in improvements in referral pathways. Any set of interventions which achieves at least 70% iFOBT screening participation and a 90% diagnostic assessment rate while costing under AUD$72 million annually would be highly cost-effective (<AUD$10,000/LYS) and save 23,000 additional lives from 2020-2040.

Economic evaluations of screening strategies for the early detection of colorectal cancer in the average-risk population: A systematic literature review

Background

Colorectal cancer (CRC) screening has proven effective in reducing CRC mortality. This study aimed to systematically review, and evaluate the reporting quality, of the economic evidence regarding CRC screening in average-risk individuals.

Methods

Databases searched included Medline, EMBASE, National Health Service Economic Evaluation, Database of Abstracts of Reviews of Effects, Cost-Effectiveness Analysis registry, EconLit, and Health Technology Assessment database. Eligible studies were cost-effectiveness and cost-utility analyses comparing CRC screening strategies in average-risk individuals, published in English or Spanish, between January 2012 and November 2018. Reporting quality was assessed using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist.

Results

Of 1,993 publications initially retrieved, 477 were excluded by duplicate review, 1,449 by title/abstract review, and 34 by full-text review. Finally, 33 publications were included in the qualitative synthesis. Most studies were conducted in Europe (36,4%), followed by United States (24,2%) and Asia (24,2%). The main screening modalities considered were fecal immunochemical tests (70%), colonoscopy (67%), guaiac fecal occult blood test (42%) and flexible sigmoidoscopy (30%). In most studies, CRC screening was deemed cost-effective compared to no screening. Sensitivity analyses indicated that cost of CRC screening tests, adherence to screening, screening test sensitivity, and cost of CRC treatment had the greatest impact on cost-effectiveness results across studies. The majority of studies (73%) adequately reported at least 50% of the items included in the CHEERS checklist. Least well reported items included setting, study perspective, discount rate, model choice, and methods to identify effectiveness data or to estimate resource use and costs.

Conclusions

CRC screening is an efficient alternative to no screening. Nevertheless, it is not possible to conclude which strategy should be preferred for population-based screening programs. Although we observed an overall good adherence to CHEERS recommendations, there is still room for improvement in economic evaluations reporting in this field.

Enhancing bowel screening: Preventing colorectal cancer by flexible sigmoidoscopy in New Zealand

OBJECTIVES

The prevention of colorectal cancer (CRC) attainable from introducing once-in-a-lifetime flexible sigmoidoscopy (FSIG) screening was assessed.

STUDY DESIGN

This is a review of relevant available information for the assessment of the impact and resource demands of FSIG in New Zealand.

METHODS

The reduction in bowel cancer incidence achievable by one-off FSIG screening from 50 to 59 years of age, an age group for which bowel screening is not currently offered, was reviewed. The prevention of CRC attainable from an offer of screening at 55 years of age in New Zealand was also estimated. The number and cost of the FSIG screening procedures required and referrals for colonoscopies and the savings in treatment were calculated.

RESULTS

Annually, about 27,500 FSIG screening procedures would be required if 50% of those turning 55 years of age accepted an offer of once-in-a-lifetime FSIG screening. This would result in three-four-fold fewer people being referred for colonoscopy than in the national 2-yearly faecal immunochemical test (FIT) screening programme and subsequently reduce demand for colonoscopy from a false-positive FIT. The number of CRC cases prevented would increase over 17 years to more than 300 per year by 2033. After 10-15 years of screening, the annual savings in health service costs, primarily from CRC prevented, were sufficient to completely fund the FSIG screening.

CONCLUSIONS

Inclusion of FSIG screening in the national bowel screening programme would significantly reduce both the incidence and mortality of CRC in New Zealand, reduce the colonoscopy demand of current bowel screening and reduce long-term health service costs.

Benefits, Harms, and Cost-Effectiveness of Potential Age Extensions to the National Bowel Cancer Screening Program in Australia

BACKGROUND

The Australian National Bowel Cancer Screening Program (NBCSP) is rolling out 2-yearly immunochemical fecal occult blood test screening in people aged 50 to 74 years. This study aimed to evaluate the benefits, harms, and cost-effectiveness of extending the NBCSP to younger and/or older ages.

METHODS

A comprehensive validated microsimulation model, Policy1-Bowel, was used to simulate the fully rolled-out NBCSP and alternative strategies assuming screening starts at 40 or 45 years and/or ceases at 79 or 84 years given three scenarios: (i) perfect adherence (100%), (ii) high adherence (60%), and (ii) low adherence (40%, as currently achieved).

RESULTS

The current NBCSP will reduce colorectal cancer incidence (mortality) by 23% to 51% (36% to 74%) compared with no screening (range reflects participation); extending screening to younger or older ages would result in additional reductions of 2 to 6 (2 to 9) or 1 to 3 (3 to 7) percentage points, respectively. With an indicative willingness-to-pay threshold of A$50,000/life-year saved (LYS), only screening from 50 to 74 years [incremental cost-effective ratio (ICER): A$2,984-5,981/LYS) or from 45 to 74 years (ICER: A$17,053-29,512/LYS) remained cost-effective in all participation scenarios. The number-needed-to-colonoscope to prevent a death over the lifetime of a cohort in the current NBCSP is 35 to 49. Starting screening at 45 years would increase colonoscopy demand for program-related colonoscopies by 3% to 14% and be associated with 55 to 170 additional colonoscopies per additional death prevented.

CONCLUSIONS

Starting screening at 45 years could be cost-effective, but it would increase colonoscopy demand and would be associated with a less favorable incremental benefits-to-harms trade-off than screening from 50 to 74 years.

IMPACT

The study underpins recently updated Australian colorectal cancer management guidelines that recommend that the NBCSP continues to offer bowel screening from 50 to 74 years.