National Bowel Cancer Screening Program Research Articles

The National Bowel Cancer Screening Programme: a service for the asymptomatic or a pathway acting as a safety net?

The National Bowel Cancer Screening Programme: a service for the asymptomatic or a pathway acting as a safety net?

National screening for colorectal cancer is associated with stage shift to earlier diagnosis.

Australia's National Bowel Cancer Screening Program consists of an immunohistochemical faecal occult blood test, targeting adults aged 50-74. Existing literature supports the principle of early detection of colorectal cancer (CRC) via national screening, but little is known about the association between colonoscopy or polypectomy rates and CRC stage over time. The aim of this study is to identify the longitudinal change to colonoscopy and polypectomy rates, and any stage shift associated with this screening program. A retrospective data-linkage study was performed using the Australian national health database (Medicare) to obtain colonoscopy and polypectomy rates between 1998 and 2017. A second prospective database of CRC resection specimens was analysed for this period. The cohort was divided based on time intervals related to the National Bowel Cancer Screening Program: pre-commencement 1998-2006 (Period A), immediately post-commencement 2007-2011 (Period B), and subsequent years 2012-2017 (Period C). Linear regression was used to test relation between annualized predictor and response variables. Annual colonoscopy rates doubled, and polypectomy rates tripled during the study (P < 0.001). Annual colonoscopy rate correlated to a lower T-stage (P = 0.038) and lower N-stage (P = 0.026), and there was a 7% increase in early CRC (stage I-II) in Period C (P < 0.001). Across the study period there was also a significant increase in right-sided tumours, and concurrent MMR deficiency and BRAF mutation. Polypectomy and colonoscopy rates increased after the introduction of the National Bowel Cancer screening program. There was a clinically significant shift to earlier CRC stage which manifested 5 years after its implementation.

Realized impact of COVID-19 related disruptions on the National Bowel Cancer Screening Program.

Colorectal cancer is the second most common cause of cancer mortality in Australia (1). The National Bowel Cancer Screening Program (NBCSP) aims to reduce mortality through early detection with a biennial faecal occult blood test for Australians aged 50-74 years (2). Modelling predicted COVID-19 would reduce participation and delay colonoscopies despite the NBCSP continuing during the pandemic (3). This study analyses the realized impact of COVID-19 related disruptions on the NBCSP and the effect on mortality. NBCSP participation, time to colonoscopy and annualized mortality were compared before and during COVID-19. The effect on mortality was determined using a validated microsimulation model (4, 5). From 1 January 2018 to 31 December 2019, 2 497 317 people participated in the NBCSP and 168 390 received a colonoscopy, compared to 2 490 265 and 162 573 from 1 January 2020 to 31 December 2021. Relative participation decreased 6 % and the proportion of colonoscopies performed within the recommended 120 days increased 14.5%. A disproportionally greater impact was observed outside major cities and in lower socioeconomic areas. An estimated 98-111 additional colorectal cancer deaths resulted from 3 % fewer colonoscopies performed during the pandemic. This study presents the most comprehensive analysis of the realized impact of COVID-19 on the NBCSP. Catch-up screening would be best targeted at Australians from rural and lower socioeconomic areas where participation remains low. Streamlined referral pathways and additional colonoscopy provisioning is required as less than two thirds of screen positive patients receive a colonoscopy within the recommended 120 days.

Increasing bowel cancer screening using SMS in general practice: the SMARTscreen cluster randomised trial.

Australia has one of the highest incidences of colorectal cancer (CRC) worldwide. The Australian National Bowel Cancer Screening Program (NBCSP) is a best-practice, organised screening programme, but uptake is low (40.9%) and increasing participation could reduce morbidity and mortality associated with CRC. Endorsement by GPs is strongly associated with increasing screening uptake. This study (SMARTscreen) aimed to test whether a multi-intervention short message service (SMS) sent by general practices to 50-60-year-old patients who were due to receive the NBCSP kit would increase NBCSP uptake, by comparing it with usual care. A stratified cluster randomised controlled trial was undertaken, involving 21 Australian general practices in Western Victoria, Australia. For intervention practices, people due to receive the NBCSP kit within a 6-month study period were sent an SMS just before receiving the kit. The SMS included a personalised message from the person's general practice endorsing the kit, a motivational narrative video, an instructional video, and a link to more information. Control practices continued with usual care, comprising at-home testing with a faecal immunochemical test (FIT) through the NBCSP. The primary outcome was the between-arm percentage difference in uptake of FIT screening within 12 months from randomisation, which was estimated using generalised linear model regression. In total, 39.2% (1143/2914) of people in 11 intervention practices and 23.0% (583/2537) of people in 10 control practices had a FIT result in their electronic health records - a difference of 16.5% (95% confidence interval = 2.02 to 30.9). The SMS intervention increased NBCSP kit return in 50-60-year-old patients in general practice. This finding informed a larger trial - SMARTERscreen - to test this intervention in a broader Australian population.

Spatial variability in socio-demographic factors affecting participation in the Australian national bowel cancer screening program

ObjectivesThe objective of this paper is to analyse the socio-demographic and spatial patterns associated with bowel cancer screening in Australia. Despite the importance of screening in reducing mortality via early intervention, it remains the case that overall screening rates are uneven between different socio-demographic groups and geographic regions. Notwithstanding this, there is limited knowledge in Australia regarding the interplay between socio-demographics and geography in relation to bowel cancer screening. Thus, this paper explores the socio-demographic and spatial patterns of screening participation across Australian regions to better inform public health policy and programs. Study designThis is a nationwide ecological study based on aggregate spatial data. MethodsAn ecological study is conducted using bowel cancer screening rates and selected socio-demographic data measured at the Statistical Area 3 level. Geographically weighted regression software is used to conduct global and spatial regression analysis. ResultsThe global regression results show that higher rates of screening participation were associated with employment/education disengagement and volunteering while in contrast, lower rates of participation were associated with higher rates of indigenous populations, people with chronic health conditions, and people with poor English skills. Considering the spatial analysis, the analysis shows that once the spatial non-stationarity in the data is considered the influence of the variables shown to be significant in the global model, has significant spatial variability. ConclusionFrom a public health perspective, addressing shortfalls in bowel cancer screening participation is an important priority. In order to understand differences in participation rates it is important to consider both socio-demographic factors as well as the geographic or spatial distribution of these factors.

Pivot to prevent bowel cancer: Reflections on adapting an Aboriginal bowel cancer screening awareness program to a digital call to action-A commentary.

The Sydney Local Health District (SLHD) Health Promotion Unit was awarded a Cancer Institute NSW grant to raise awareness of bowel cancer and promote the National Bowel Cancer Screening Program (NBCSP) among Aboriginal communities in SLHD. The COVID-19 pandemic thwarted initial plans for face-to-face workshops and plans pivoted to digital products and dissemination of messages on a range of communication platforms. The coronavirus (COVID-19) pandemic provided staff with the freedom, flexibility, and ability to be creative in ways not possible prior to the pandemic and ultimately ended up with a superior product with a reach further than anticipated. A more comprehensive suite of digital resources addressing barriers to bowel cancer screening in the Aboriginal community was produced that is able to be used more broadly. These resources have reached a much larger population group through websites, social media, as well as TV and radio advertisements, and have the potential to be used and adapted in other local health districts and states across Australia. Adapting an Aboriginal bowel cancer screening awareness program to a digital platform is a promising approach. SO WHAT?: COVID-19 provided an opportunity to create new long-lasting partnerships and to be creative beyond the scope of the original grant. This in turn produced a product with a reach further than anticipated that can also be built on and sustained.

Economic impact of implementing optical diagnosis with a "resect and discard" strategy within the English Bowel Cancer Screening Programme: Findings from the DISCARD3 study.

Advances in endoscopic technology, such as narrow band imaging and high definition colonoscopes, offer the potential for optical diagnosis (OD) with a "resect and discard" (RD) strategy for diminutive (≤5mm) and small (6-9mm) colorectal polyps. This could help alleviate the huge cost and time burden required for histopathology. The aim of this study is to conduct an economic analysis of a RD strategy within the English Bowel Cancer Screening Programme (BCSP). A decision tree was designed to compare a RD strategy with standard histopathology for patients included in the DISCARD3 study and was extrapolated to a national BCSP patient cohort. Of the 525 patients in the DISCARD3 study, 354 were assessed for surveillance intervals (after excluding cases with colorectal cancer and at least one polyp >10 mm). 269/354 cases had polyps of which, 182 had only diminutive polyps, 77 had both small and diminutive polyps, and 10 had only small polyps. Surveillance interval concordance was 97.9% in patients with at least 1 diminutive polyp and 98.7% in patients with at least 1 diminutive or small polyp. In DISCARD3, a RD approach would reduce overall direct healthcare costs by £35,468.8 (-72.3%) for patients with diminutive polyps or by £42,666.2 (-75.0%) for patients with diminutive or small polyps. When extrapolated to the entire English BCSP, the annual savings are almost £2.4m for patients with diminutive polyps or £3.4m for patients with diminutive or small polyps, after adjusting for the costs of an OD quality assurance process (QAP). OD with a RD strategy for diminutive and small polyps during BCSP colonoscopy would offer substantial cost savings without adversly affecting surveillance interval concordance.

The Barriers to Bowel Cancer Screening Scale: Examining Structural Validity, Measurement Invariance, and Criterion Validity.

The success of national cancer screening programs, such as the National Bowel Cancer Screening Program (NBCSP) in Australia, depends on public participation, which is currently an alarming 43.5% for the NBCSP. Understanding the barriers that impede screening participation requires valid measurement instruments. This study aims to cross-validate such an instrument with a new, large, and varied sample, as well as assess measurement invariance across subsamples at a greatest risk of nonparticipation (ie, testing whether the scale functions in similar ways across groups). A cross-sectional sample of 1158 participants from the target screening population (50-74 years) provided demographic information, responses to the Barriers to Home Bowel Screening (BB-CanS) scale, and information on their previous screening participation. Both the full and the brief versions of the BB-CanS scale showed good model fit for the full sample and for gender and age subsamples. Despite the inter-factor correlations being high, the unidimensional and bi-factor models exhibited poorer fit. Improvement in fit was observed with scale refinement involving the removal of 7 items. All versions of the BB-CanS scale were invariant across gender and age subsamples. Age and gender differences emerged across several barriers and variance in all 4 barriers significantly predicted prior screening participation. The BB-CanS scale is a valid measure of 4 highly correlated barriers to home bowel cancer screening: disgust relating to screening, avoidance of test outcomes, practical difficulty (or challenges), and the need for a sense of greater autonomy. All versions of the instrument measure the equivalent construct across age and gender groups. Observed differences in barriers across at-risk groups provide targets for future intervention.

The 'hot zone policy' for colorectal cancer screening presents unique risks and opportunities for rural Australia.

Colorectal cancer has geographic inequities in Australia, with higher mortality rates and lower participation in the National Bowel Cancer Screening Program (NBCSP) in remote and rural areas. The at-home kit is temperature-sensitive, necessitating a 'hot zone policy' (HZP); kits are not sent when an area's average monthly temperature is above 30°C. Australians in HZP areas are susceptible to potential screening disruptions but may benefit from well-timed interventions to improve participation. This study describes the demographics of HZP areas and estimates the impacts of potential screening changes. The number of individuals in HZP areas was estimated, as well as correlations with remoteness, socio-economic and Indigenous status. The potential impacts of screening changes were estimated. Over a million eligible Australians live in HZP areas, which are more likely to be remote/rural, have lower socio-economic status and higher Indigenous populations. Predictive modelling estimates that any 3-month screening disruption would increase CRC mortality rates up to 4.1 times more in HZP areas vs unaffected areas, while targeted intervention could decrease mortality rates 3.4 times more in HZP areas. People living in affected areas would be negatively impacted by any NBCSP disruption, compounding existing inequities. However, well-timed health promotion could have a stronger impact.

Engaging lower screening groups: a field experiment to evaluate the impact of a multiwave national campaign on participation in the National Bowel Cancer Screening Program

ObjectivesThis field study evaluated a multiwave media campaign that aired in 2019 to promote participation in the Australian National Bowel Cancer Screening Program (NBCSP), which provides free biennial mailed-out immunochemical...

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

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

Improving colonoscopy prioritisation and promoting the National Bowel Cancer Screening Program: keys to reducing bowel cancer burden.

Australia's National Bowel Cancer Screening Program (NBCSP) has the potential to prevent almost 84 000 bowel cancer deaths if 60% program participation rates could be reached and maintained over the next two decades. Immunochemical faecal occult blood test (iFOBT) is used as an initial screening tool. Participants who test positive are referred for colonoscopy for diagnostic assessment. Concerns about colonoscopy capacity and lengthy wait times between positive iFOBT and colonoscopy have hampered efforts to promote the program. However, a separate research paper published in this issue of PHRP shows that only an estimated 10-14% of Medicare-funded colonoscopies (almost 75% of all colonoscopies) in Australia are generated by the NBCSP. Inappropriate use of colonoscopy as a primary screening tool and failure to prioritise NBCSP participants may be the main reasons for long colonoscopy wait times associated with the program. Promoting clinical practice guidelines, and the Direct Access Colonoscopy initiative for priority patients, are key to reducing colonoscopy wait times and proactive promotion of the NBCSP.

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

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. 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. 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. 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.

Long-term benefits for lower socioeconomic groups by improving bowel screening participation in South Australia: A modelling study.

The gap in bowel cancer screening participation rates between the lowest socioeconomic position (SEP) groups and the highest in Australia is widening. This study estimates the long-term health impacts and healthcare costs at current colorectal cancer (CRC) screening participation rates by SEP in South Australia (SA). A Markov microsimulation model for each socioeconomic quintile in SA estimated health outcomes over the lifetime of a population aged 50-74 years (total n = 513,000). The model simulated the development of CRC, considering participation rates in the National Bowel Cancer Screening Program and estimated numbers of cases of CRC, CRC deaths, adenomas detected, mean costs of screening and treatment, and quality adjusted life years. Screened status, stage of diagnosis and survival were obtained for patients diagnosed with CRC in 2006-2013 using data linked to the SA Cancer Registry. We predict 10915 cases of CRC (95%CI: 8017─13812) in the lowest quintile (Q1), 17% more than the highest quintile (Q5) and 3265 CRC deaths (95%CI: 2120─4410) in Q1, 24% more than Q5. Average costs per person, were 29% higher in Q1 at $11997 ($8754─$15240) compared to Q5 $9281 ($6555─$12007). When substituting Q1 screening and diagnostic testing rates with Q5's, 17% more colonoscopies occur and adenomas and cancers detected increase by 102% in Q1. Inequalities were evident in CRC cases and deaths, as well as adenomas and cancers that could be detected earlier. Implementing programs to increase screening uptake and follow-up tests for lower socioeconomic groups is critical to improve the health of these priority population groups.

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

Colonoscopy use in Australia was compiled using Medicare Benefits Schedule (MBS) claims for colonoscopies from 2001 to 2019. From these data, projections were made from 2020 to 2030. Policy1-Bowel, a microsimulation model, was used to estimate NBCSP-related colonoscopy demand from screening follow-up and colonoscopic surveillance from 2006 to 2030. MBS-funded colonoscopy use increased from 284 676 in 2001 to 663 213 in 2019. Annual use is projected to be more than 780 000 by 2030. Of these, 10-14% are projected to be generated by the NBCSP. Per-capita MBS-funded colonoscopy utilisation increased 0.2% annually over 2015-2019, a slowing of growth compared to previous trends. The NBCSP accounts for a modest fraction of colonoscopy use in Australia, and a better understanding of colonoscopy use not associated with the NBCSP is needed. Promoting adherence to guideline-recommended iFOBT and colonoscopy use could ease pressure on services and improve outcomes.

High Adenoma Detection Rates in Fecal Immunochemical Test-Based Colorectal Cancer Screening: Interim Results of the National Bowel Cancer Screening Program in Qatar.

Colorectal cancer is one of the most common cancers globally. Recent reductions in mortality rates have been primarily attributed to screening programs. The State of Qatar established a national bowel cancer screening program in 2016. Fecal immunochemical testing (FIT) was used for average-risk individuals aged 50 to 74 years. Fecal immunochemical testing -positive participants were referred for total colonoscopy to detect polyps and cancers. Among 32,751 FIT invitees, 11,130 took the test, and 758 (6%) of those were FIT positive. Of these, 375 (56.13%) participants underwent a colonoscopy, and polyps were detected in 198 (52.8%) and cancers in 19 (5.1%) participants. The adenoma detection rate exceeded 40%. The high yield of polyps and cancers in the screening program justifies an active, resource-intensive, and organized bowel cancer screening effort. The high adenoma detection rate in a FIT-based program warrants recalibration of target adenoma detection rates in screening programs.

Psychological distress and bowel cancer screening participation.

To better understand barriers to participation in mail-out bowel cancer screening programs, two survey studies tested the relationship between psychological distress and self-reported bowel cancer screening. First, a nationally representative sample of Australians N=5421 completed measures of bowel cancer screening and psychological distress (using the Kessler Psychological Distress Scale; K10). Second, N=479 completed a survey measuring participation in the National Bowel Cancer Screening Program (NBCSP) and psychological distress using the Depression, Anxiety and Stress Scale. In both studies, logistic regressions were conducted to test relationships between psychological distress and self-reported screening participation. Study one found that psychological distress had a significant quadratic effect on having ever screened for bowel cancer, where screening rates were similar for those with low, moderate, or high levels of distress, but were lower for those with very high levels of distress. In study two, depression scores had a negative linear relationship with NBCSP participation (higher depression levels were associated with lower screening participation), and anxiety had a quadratic effect whereby NBCSP participation rates were higher with increasing levels of anxiety except in the severe category, where participation was significantly lower. Findings indicate that psychological distress has a complex relationship with screening, and those with extreme levels of distress consistently show lower participation rates. Special efforts to encourage screening may be required for those experiencing extreme psychological distress and mental health disorders.

Bowel cleansing efficacy of 1L NER1006versus macrogol and 3L polyethylene glycol using split-dose administration.

Colonoscopies are an important diagnostic technique in the detection of colorectal cancer and colonic disease. Adequate examination is dependent on the degree of mucosal visibility, with poor cleansing impeding the detection of neoplasms. These patients require shorter colonoscopy surveillance intervals, longer hospital stays, and increased healthcare costs-rendering a screening colonoscopy cost-ineffective. In Australia and the Gold Coast Hospital and Health Service (GCHHS), macrogol and 3L of polyethylene glycol are the preferred regimen given its safety profile and efficacy. Yet, little is known locally about the use of the new low-volume bowel preparation NER1006 (Plenvu) given its recent registration with the Therapeutic Goods of Australia (TGA). The primary outcome assessed the bowel cleansing efficacy of NER1006 compared with 7 days of macrogol and 3L of polyethylene glycol using the Boston Bowel Preparation Scale (BBPS), while also assessing the influence of notable patient characteristics such as age, gender, body mass index (BMI), and the patients Charlson comorbidity index (CCI). Secondary outcomes assessed the polyp detection rate and procedural factors including cecal intubation, scope withdrawal time, and rebooking rates. Data from all patients who underwent an outpatient colonoscopy procedure at GCHHS between 1 July 2020 and 30 September 2020 were analyzed. Patients were aged 50-74 years of age and were referred for a screening colonoscopy due to a positive fecal occult blood test (FOBT) result from the National Bowel Cancer Screening Program. Of the 238 patients who met the inclusion criteria, 108 patients received NER1006 and 130 patients received macrogol and 3L polyethylene glycol. NER1006 achieved superior overall (P< 0.001) and right-sided colon cleansing (P= 0.016). There was an even distribution of males and females (P= 0.118), the mean age of both cohorts was <65 years of age. The macrogol and 3L polyethylene glycol group had a statistically higher BMI (P< 0.001) and CCI (P< 0.001). Cecal intubation success was achieved in both cohorts (≥95%) and scope withdrawal time was ≥6min, polyp detection was non-superior (P= 0.824), but superior in NER1006 when BBPS ≥6 (P= 0.002). Rebooking rates were significantly lower in the NER1006 group (P= 0.013). This study demonstrated that NER1006 was superior in terms of overall and right-sided bowel cleansing as a primary endpoint. Patient factors demonstrated to be independent predictors of inadequate bowel preparation. Future studies should aim to explore the safety and tolerability of NER1006 while also assessing the bowel cleansing effectiveness in patients with a high BMI and comorbidity index.

Incidental findings in the bowel cancer population screening program: other polyps and malignancies - A nationwide study.

The introduction of bowel cancer population screening programs has had a profound impact on gastrointestinal pathology. While the focus is mainly on quality assurance of diagnoses relevant for the outcome of these programs (colorectal cancer and its precursors), incidental findings are increasingly diagnosed. The incidence of such findings is largely unknown. Therefore, we investigated the incidence of incidental findings within the national screening program of the Netherlands. From the Dutch nationwide pathology databank (PALGA), we retrieved all histological diagnoses of patients participating in the national bowel cancer screening program from the start in 2014 until 1/1/2021. Descriptive statistics were used. During these 7 years, in total 9407 other polyps and malignancies (262 per 10,000 colonoscopies) were diagnosed. The majority (65%) were classified as inflammatory polyps. The most common malignancies were neuroendocrine tumours (n = 198, 6 per 10,000 colonoscopies); less common were lymphomas (n = 64) and metastases (n = 33). Mesenchymal polyps, such as leiomyomas and lipomas, were relatively common (27 and 16 per 10,000 colonoscopies, respectively), in comparison with neural polyps such as perineuriomas, ganglioneuromas, and neurofibromas (respectively 3, 2, and 1 per 10,000 colonoscopies). This is the largest study into the incidence of nonconventional colorectal polyps and malignancies in a homogeneous cohort of asymptomatic patients. Several of these diagnoses may have consequences for treatment and follow-up, in particular the malignancies and detection of patients with hereditary cancer syndromes.

Impact of changes to the interscreening interval and faecal immunochemical test threshold in the national bowel cancer screening programme in England: results from the FIT pilot study

IntroductionThe NHS Bowel Cancer Screening Programme (BCSP) faces endoscopy capacity challenges from the COVID-19 pandemic and plans to lower the screening starting age. This may necessitate modifying the interscreening interval or threshold.MethodsWe analysed data from the English Faecal Immunochemical Testing (FIT) pilot, comprising 27,238 individuals aged 59–75, screened for colorectal cancer (CRC) using FIT. We estimated screening sensitivity to CRC, adenomas, advanced adenomas (AA) and mean sojourn time of each pathology by faecal haemoglobin (f-Hb) thresholds, then predicted the detection of these abnormalities by interscreening interval and f-Hb threshold.ResultsCurrent 2-yearly screening with a f-Hb threshold of 120 μg/g was estimated to generate 16,092 colonoscopies, prevent 186 CRCs, detect 1142 CRCs, 7086 adenomas and 4259 AAs per 100,000 screened over 15 years. A higher threshold at 180 μg/g would reduce required colonoscopies to 11,500, prevent 131 CRCs, detect 1077 CRCs, 4961 adenomas and 3184 AAs. A longer interscreening interval of 3 years would reduce required colonoscopies to 10,283, prevent 126 and detect 909 CRCs, 4796 adenomas and 2986 AAs.ConclusionIncreasing the f-Hb threshold was estimated to be more efficient than increasing the interscreening interval regarding overall colonoscopies per screen-benefited cancer. Increasing the interval was more efficient regarding colonoscopies per cancer prevented.