Interval Colorectal Cancer Incidence Among Subjects Undergoing Multiple Rounds of Fecal Immunochemical Testing

Proportions and characteristics of interval cancer in annual fecal immunochemical test screening and postcolonoscopy colorectal cancer: Results from a Japanese multicenter prospective study using questionnaires, the C-DETECT study

OBJECTIVES

There are several types of colorectal cancer (CRC) according to the detection methods and intervals, including interval CRC (iCRC) and postcolonoscopy CRC (PCCRC). We aimed to examine their proportions and characteristics.

METHODS

We conducted a multicenter prospective study using questionnaires in Japan ("C-DETECT study"), in which differences in CRC characteristics according to detection methods and intervals were examined from consecutive adult patients. Because the annual fecal immunochemical test (FIT) was used in population-based screening, the annual FIT-iCRC was assessed.

RESULTS

In total, 1241 CRC patients (1064 with invasive CRC) were included. Annual FIT-iCRC (a), 3-year PCCRC (b), and CRC detected within 1 year after a positive FIT with noncompliance to colonoscopy (c) accounted for 4.5%, 7.0%, and 3.9% of all CRCs, respectively, and for 3.9%, 5.4%, and 4.3% of invasive CRCs, respectively. The comparison among these (a, b, c) and other CRCs (d) demonstrated differences in the proportions of ≥T2 invasion ([a] 58.9%, [b] 44.8%, [c] 87.5%, [d] 73.0%), metastasis ([a] 33.9%, [b] 21.8%, [c] 54.2%, [d] 43.9%), right-sided CRC ([a] 42.9%, [b] 40.2%, [c] 18.8%, [d] 28.6%), and female sex ([a] 53.6%, [b] 49.4%, [c] 27.1%, [d] 41.6%). In metastatic CRC, (a) and (b) showed a higher proportions of BRAF mutations ([a] [b] 12.0%, [c] [d] 3.1%).

CONCLUSIONS

Annual FIT-iCRC and 3-year PCCRC existed in nonnegligible proportions. They were characterized by higher proportions of right-sided tumors, female sex, and BRAF mutations. These findings suggest that annual FIT-iCRC and 3-year PCCRC may have biological features different from those of other CRCs.

Interval cancers in a national colorectal screening programme based on faecal immunochemical testing: Implications for faecal haemoglobin concentration threshold and sex inequality

OBJECTIVE

To compare interval cancer proportions (ICP) in the faecal immunochemical test (FIT)-based Scottish Bowel Screening Programme (SBoSP) with the former guaiac faecal occult blood test (gFOBT)-based SBoSP and investigate associations between interval cancer (IC) and faecal haemoglobin concentration (f-Hb) threshold, sex, age, deprivation, site, and stage.

METHODS

The ICP data from first year of the FIT-based SBoSP and the penultimate year of the gFOBT-based SBoSP were compared in a prospective cohort design.

RESULTS

With FIT, 801 colorectal cancers (CRCs) were screen detected (SDC), 802 were in non-participants, 548 were ICs, 39 were colonoscopy missed and 72 were diagnosed after incomplete screening; with gFOBT: 540, 904, 556, 45, and 13, respectively. FIT had a significantly higher proportion of SDC compared to IC than gFOBT. For FIT and gFOBT, ICP was significantly higher in women than men. As f-Hb threshold increased, ICP increased and, for any f-Hb threshold for men, a lower threshold was required for comparable ICP in women. In Scotland, the current threshold of ≥80 µg Hb/g faeces would have to be lowered to ≥40 µg Hb/g faeces for women to achieve sex equality for ICP. In the FIT-based SBoSP, there were four times as many stage I SDC than IC. This was reversed in advanced stages, with twice as many stage IV CRC diagnosed as IC versus SDC.

CONCLUSIONS

Reducing the numbers of IC requires lowering the f-Hb threshold. Using different f-Hb thresholds for women and men could eliminate the sex disparity, but with additional colonoscopy.

Interval Cancer in Population-Based Colorectal Screening Programmes: Incidence and Characteristics of Tumours

The objective of this study is to evaluate interval cancer (IC) in colorectal cancer (CRC) screening, which is CRC diagnosed in an individual after having received a negative faecal occult blood test and before the next invitation to participate in screening. A follow-up study was conducted on a cohort of participants in the first three screening rounds of four colorectal cancer screening programmes in Spain, n = 664,993. A total of 321 ICs and 2120 screen-detected cancers (SCs) were found. The IC and SC rates were calculated for each guaiac (gFOBT) or immunochemical (FIT) test. A Cox regression model was used to estimate the hazard ratios (HR) of IC risk factors. A nested case-control study was carried out to compare IC and SC tumour characteristics. The IC rate was 1.16‱ with the gFOBT and 0.35‱ with the FIT. Men and people aged 60-69 showed an increased probability of IC (HR = 1.81 and HR = 1.95, respectively). There was a decreased probability of IC in individuals who regularly participated in screening, HR = 0.62 (0.47-0.82). IC risk gradually rose as the amount of Hb detected in the FIT increased. IC tumours were in more advanced stages and of a larger size than SC tumours, and they were mostly located in the cecum. These results may play a key role in future strategies for screening programmes, reducing IC incidence.

Post-colonoscopy colorectal cancer: A population-based cohort study of fecal occult blood test-positive colonoscopies

BACKGROUND

Data on post-colonoscopy colorectal cancers (PCCRCs) after fecal occult blood test (FOBT)-positive colonoscopies is scarce (guaiac-based (gFOBT) or fecal immunochemical test (FIT)).

AIMS

Evaluate the prevalence and characteristics of PCCRCs in the French gFOBT CRC screening program.

METHODS

Retrospective population-based cohort study of all gFOBT-positive colonoscopies performed among individuals aged 50-74 between 2003 and 2014 within the CRC screening program organized in the Haut-Rhin (Alsace, France). The main outcome was PCCRC-3y rate. Adenoma detection rates (ADRs) calculated on gFOBT-positive colonoscopies were compared to those calculated on FIT-positive colonoscopies performed by the same gastroenterologists.

RESULTS

Overall, 9106 gFOBT-positive colonoscopies performed by 36 gastroenterologists were included. Sixteen PCCRC-3y and 31 PCCRC-5y were diagnosed (68.8 % and 58.1 % were true interval PCCRCs respectively). The unadjusted PCCRC-3y rate was 2.4 % [95 % confidence interval (CI) 1.4 %-3.9 %]. The risk for PCCRC-5y was significantly higher when the gastroenterologist's ADR was <35 % compared to ≥35 % (HR 2.17 [95 %CI 1.19-3.93]). The mean absolute difference for ADR between gFOBT- and FIT-positive colonoscopies was 16.3 % in favor of FIT-positive colonoscopies.

CONCLUSION

PCCRC-3y prevalence was low, estimated at 2.4 %. We suggest that the minimum standard for ADR in gFOBT- and FIT-positive colonoscopies should be set at 35 % and 50 % to 55 % respectively, in the French screening program.

Interval colorectal cancers after negative faecal immunochemical test in the New Zealand Bowel Screening Pilot

OBJECTIVE

Evaluate the diagnostic performance of faecal immunochemical test (FIT), identify risk factors for FIT-interval colorectal cancers (FIT-IC) and describe long-term outcomes of participants with colorectal cancers (CRC) in the New Zealand Bowel Screening Pilot (BSP).

DESIGN

From 2012 to 2017, the BSP offered eligible individuals, aged 50-74 years, biennial screening using a quantitative FIT with positivity threshold of 15 µg haemoglobin (Hb)/g faeces. Retrospective review of prospectively maintained data extracted from the BSP Register and New Zealand Cancer Registry identified any CRC reported in participants who returned a definitive FIT result. Further details were obtained from hospital records. FIT-ICs were primary CRC diagnosed within 24 months of a negative FIT. Factors associated with FIT-ICs were identified using logistic regression.

RESULTS

Of 387 215 individuals invited, 57.4% participated with 6.1% returning positive FIT results. Final analysis included 520 CRC, of which 111 (21.3%) met FIT-IC definition. Overall FIT sensitivity for CRC was 78.7% (95% CI=74.9% to 82.1%), specificity was 94.1% (95% CI=94.0% to 94.2%). In 78 (70.3%) participants with FIT-IC, faecal Hb was reported as undetectable. There were no significant associations between FIT-IC and age, sex, ethnicity and deprivation. FIT-ICs were significantly associated with proximal tumour location, late stage at diagnosis, high-grade tumour differentiation and subsequent round screens. Median follow-up time was 74 (2-124) months. FIT-IC had significantly poorer overall survival.

CONCLUSION

FIT sensitivity in BSP compared favourably to published data. FIT-ICs were more likely to be proximal tumours with poor long-term outcomes. Further lowering of FIT threshold would have minimal impact on FIT-IC.

Performance and effectiveness of hepatocellular carcinoma screening in individuals with HBsAg seropositivity in China: a multicenter prospective study

Current guidelines recommend hepatocellular carcinoma (HCC) surveillance for at-risk individuals, including individuals with hepatitis B virus infection. However, the performance and survival benefits of annual screening have not been evaluated through multicenter prospective studies in a Chinese population. Between 2017 and 2021, we included 14,426 participants with hepatitis B surface antigen seropositivity in an annual HCC screening study in China using a multicenter prospective design with ultrasonography and serum alpha-fetoprotein. After four rounds of screening and follow-up, the adjusted hazard ratios of death after correction for lead-time and length-time biases for screen-detected cancers at the prevalent and incident rounds were 0.74 (95% confidence interval = 0.60-0.91) and 0.52 (95% confidence interval = 0.40-0.68), respectively. A meta-analysis demonstrated that HCC screening was associated with improved survival after adjusting for lead-time bias. Our findings highlight the 'real-world' feasibility and effectiveness of annual HCC screening in community settings for the early detection of HCC and to improve survival.

The effect of numeric information about the likelihood of receiving a false negative or false positive result on people's attitudes towards colorectal cancer screening using faecal immunochemical testing (FIT)

OBJECTIVE

To examine the impact of numeric risk information about false negative (FN) and false positive (FP) rates in fecal immunochemical testing (FIT) on attitudes towards screening.

METHODS

102 people aged 45-55, living in the UK, read 6 hypothetical vignettes presented online about the use of FIT kits to detect colorectal cancer, in which information about FN and FP rates was systematically varied.

RESULTS

Numeric FN risk information reduced people's interest in screening, perception of screening effectiveness and lowered trust in screening compared to verbal FN information. Verbal FN information reduced perceptions of screening effectiveness and trust compared to no FN information. People with high subjective numeracy reported lower trust in screening following the provision of numeric FN information but numeracy did not moderate any other associations. FP information did not affect attitudes towards FIT testing.

CONCLUSION

Numeric FN risk information decreased people's perceptions of screening effectiveness and trust in the results of screening. While it influenced people's interest in screening, the effect was small.

PRACTICE IMPLICATIONS

Numeric FN information has a small effect on interest in screening and could promote informed decision making without affecting screening uptake.

Socioeconomic inequalities in interval colorectal cancer are explained by differences in faecal haemoglobin concentration and age: a register-based cohort study

OBJECTIVE

To estimate the risk of interval colorectal cancer (CRC) in faecal immunochemical test (FIT) negative screening participants according to socioeconomic status.

DESIGN

In this register-based study, first round FIT negative (<20 µg hb/g faeces) screening participants (biennial FIT, citizens aged 50-74) were followed to estimate interval CRC risk. Multivariate Cox proportional hazard regression models estimated HRs based on socioeconomic status defined by educational level and income. Models were adjusted for age, sex and FIT concentration.

RESULTS

We identified 829 (0.7‰) interval CRC in 1 160 902 individuals. Interval CRC was more common in lower socioeconomic strata with 0.7‰ for medium-long higher education compared with 1.0‰ for elementary school and 0.4‰ in the highest income quartile compared with 1.2‰ in the lowest. These differences did not translate into significant differences in HR in the multivariate analysis, as they were explained by FIT concentration and age. HR for interval CRC was 7.09 (95% CI) for FIT concentrations 11.9-19.8 µg hb/g faeces, and 3.37 (95% CI) for FIT between 7.2 and 11.8 compared with those <7.2. The HR rose with increasing age ranging from 2.06 (95% CI 1.45 to 2.93) to 7.60 (95% CI 5.63 to 10.25) compared with those under 55 years.

CONCLUSION

Interval CRC risk increased with decreasing income, heavily influenced by lower income individuals more often being older and having increased FIT concentrations. Individualising screening interval based on age and FIT result, may decrease interval CRC rates, reduce the social gradient and thereby increase the screening efficiency.

Sensitivity of fecal immunochemical test and risk factors for interval colorectal cancer in a French population

BACKGROUND

Colorectal cancer (CRC) screening using fecal immunochemical testing (FIT) aims to detect pre-symptomatic colorectal lesions and reduce CRC mortality.

AIMS

The objectives of this study were to determine the FIT sensitivity for diagnosis of CRC, the impact of diagnostic circumstances on treatment and survival, and risk factors for interval cancer (IC).

METHODS

This population-based study evaluated the 2016-2017 CRC screening campaign in Finistère, France. CRCs were classified according to diagnostic circumstances: screen-detected CRC (SD-CRC), CRC with delayed diagnosis, IC after negative FIT (FIT-IC), post-colonoscopy CRC, CRC in non-responders and CRC in the excluded population.

RESULTS

This study included 909 CRCs: 248 SD-CRCs (6% of positive FIT) and 60 FIT-ICs (0.07% of negative FIT). The FIT sensitivity for CRC was 80.5% (CI95%: 76.1-84.9) at the threshold of 30 µg hemoglobin/g feces used in France. In multivariate analysis, proximal (OR:6.73) and rectal locations (OR:7.52) were associated with being diagnosed with FIT-IC rather than SD-CRC. The FIT positivity threshold maximizing the sum of sensitivity and specificity was found to be 17 µg/g, with 14 additional CRCs diagnosed compared to the current threshold.

CONCLUSIONS

Our study confirms the good sensitivity of FIT. A decrease of the FIT detection threshold could optimize sensitivity.

Missed colorectal cancers in a fecal immunochemical test-based screening program: Molecular profiling of interval carcinomas

BACKGROUND

For optimizing fecal immunochemical test (FIT)-based screening programs, reducing the rate of missed colorectal cancers (CRCs) by FIT (FIT-interval CRCs) is an important aspect. Knowledge of the molecular make-up of these missed lesions could facilitate more accurate detection of all (precursor) lesions.

AIM

To compare the molecular make-up of FIT-interval CRCs to lesions that are detected by FIT [screen-detected CRCs (SD-CRCs)].

METHODS

FIT-interval CRCs observed in a Dutch pilot-program of FIT-based screening were compared to a control group of SD-CRCs in a 1:2 ratio, resulting in 27 FIT-interval CRC and 54 SD-CRCs. Molecular analyses included microsatellite instability (MSI), CpG island methylator phenotype (CIMP), DNA sequence mutations and copy number alterations (CNAs).

RESULTS

Although no significant differences were reached, FIT-interval CRCs were more often CIMP positive and MSI positive (33% CIMP in FIT-interval CRCs vs 21% in SD-CRCs (P = 0.274); 19% MSI in FIT-interval CRCs vs 12% in SD-CRCs (P = 0.469)), and showed more often serrated pathway associated features such as BRAF (30% vs 12%, P = 0.090) and PTEN (15% vs 2.4%, P = 0.063) mutations. APC mutations, a classic feature of the adenoma-carcinoma-sequence, were more abundant in SD-CRCs (68% vs 40% in FIT-interval CRCs P = 0.035). Regarding CNAs differences between the two groups; FIT-interval CRCs less often showed gains at the regions 8p11.22-q24.3 (P = 0.009), and more often gains at 20p13-p12.1 (P = 0.039).

CONCLUSION

Serrated pathway associated molecular features seem to be more common in FIT-interval CRCs, while classic adenoma carcinoma pathway associated molecular features seem to be more common in SD-CRCs. This indicates that proximal serrated lesions may be overrepresented among FIT-interval CRCs.

Adenoma Detection Rate and Risk for Interval Postcolonoscopy Colorectal Cancer in Fecal Immunochemical Test-Based Screening : A Population-Based Cohort Study

BACKGROUND

The adenoma detection rate (ADR) is an essential quality indicator for endoscopists performing colonoscopies for colorectal cancer (CRC) screening as it is associated with postcolonoscopy CRCs (PCCRCs). Currently, data on ADRs of endoscopists performing colonoscopies in fecal immunochemical testing (FIT)-based screening, the most common screening method, are scarce. Also, the association between the ADR and PCCRC has not been demonstrated in this setting.

OBJECTIVE

To evaluate the association between the ADR and PCCRC risk in colonoscopies done after a positive FIT result.

DESIGN

Population-based cohort.

SETTING

Dutch, FIT-based, CRC screening program.

PARTICIPANTS

Patients undergoing colonoscopy, done by accredited endoscopists, after a positive FIT result.

MEASUREMENTS

Quality indicator performance and PCCRC incidence for colonoscopies in FIT-positive screenees were assessed. The PCCRCs were classified as interval, a cancer detected before recommended surveillance, or noninterval. The association between ADR and interval PCCRC was evaluated with a multivariable Cox regression model and PCCRC incidence was determined for different ADRs.

RESULTS

362 endoscopists performed 116 360 colonoscopies with a median ADR of 67%. In total, 209 interval PCCRCs were identified. The ADR was associated with interval PCCRC, with an adjusted hazard ratio of 0.95 (95% CI, 0.92 to 0.97) per 1% increase in ADR. For every 1000 patients undergoing colonoscopy, the expected number of interval PCCRC diagnoses after 5 years was approximately 2 for endoscopists with ADRs of 70%, compared with more than 2.5, almost 3.5, and more than 4.5 for endoscopists with ADRs of 65%, 60%, and 55%, respectively.

LIMITATION

The relative short duration of follow-up (median, 52 months) could be considered a limitation.

CONCLUSION

The ADR of endoscopists is inversely associated with the risk for interval PCCRC in FIT-positive colonoscopies. Endoscopists performing colonoscopy in FIT-based screening should aim for markedly higher ADRs compared with primary colonoscopy.

PRIMARY FUNDING SOURCE

None.

Evaluation of a colorectal cancer screening program composed of successive waves of different tests: The experience of the French Calvados County

BACKGROUNDS

The value of colorectal cancer (CRC) screening program in a population with a limited participation rate is debated. This study assesses the real-life performances of different screening tests in a population benefiting from an organized program and included in a cancer registry.

METHODS

Patients who participated in at least one screening campaign between 2004 and 2016 were included. Four screening procedures were used: Hemoccult II, Magstream, Hemoccult and Magstream combined, and OC Sensor. Data were crossed with the Digestive Cancer Registry of Calvados to detect CRCs diagnosed during this period. The main outcomes were CRC detection and the incidence rate of interval cancers.

RESULTS

Screening consisted of 325,083 tests in 134,498 patients. Of the 2580 CRCs detected in patients aged 50-74, 534 (20.7 %) were screen-detected. OC Sensor had the highest sensitivity for CRC detection (83.7 %, 95 % CI [76.8-89.1 %]) and the lowest interval cancer rate (2.0 per 10,000 person-years, 95 % CI [1.4-2.7]) compared with other screening tests, excluding combinations. The overall participation rate was 28.9 %.

CONCLUSION

Real-life differences in performance between different screening tests exist, and OC Sensor appears to be the best. The low participation rate suggests that the rate of screen-detected CRC could be higher.

Clinical Effectiveness of Faecal Immunochemical Test in the Early Detection of Colorectal Cancer-An Umbrella Review

Introduction: The colorectal cancer prognosis depends on the stage of the neoplasm; therefore, its early detection plays an important role. The aim of the study is evaluation of the sensitivity, specificity, and clinical effectiveness of the faecal immunochemical test in the early colorectal cancer detection. Methods: The clinical analysis was based on the results of the studies included in a systematic review conducted in accordance with the Cochrane Collaboration guidelines. The following medical information sources were searched: Medline (via PubMed), Embase (via Ovid), The Cochrane Library. Results: From 241 citations, 13 studies were included in this review. All included studies had a low risk of bias. The faecal immunochemical test is highly specific in all analysed populations ranging from 85% to 97%. In most of the found studies, sensitivity is over 75%. The faecal immunochemical test screening also determines a reduction in death (10-59%) due to colorectal cancer. Conclusions: The faecal immunochemical test is an effective and cost-effective method of conducting population-wide colorectal cancer screening. It is an alternative or complementary to other screening tests, including colonoscopy.

A comprehensive assessment of the impact of a colorectal cancer screening program in a northern Italian area

BACKGROUND

The impact of a faecal immunochemical test-based colorectal cancer (CRC) screening program in terms of patient prognosis could be affected by lead-time bias, which artificially increases the survival of screen-detected patients due to the early diagnosis.

AIMS

To provide a description of the impact of the CRC screening program in the Trentino Region (Italy), including the Cure Fraction (CF), a prognostic indicator not affected by lead-time bias.

METHODS

The program started in 2008, inviting the resident population aged 50-69 years. In this retrospective cohort study, 1,697 CRC diagnosed between 2003 and 2014 in patients aged 50-69 years were classified as pre-screening (PS), screen-detected (SD), interval cancers (IC) and not-screen-detected (NSD). We compared groups by stage at diagnosis and CF. Trends in CRC mortality were reported.

RESULTS

The proportion of stage I among SD cases was 51%, higher than PS (19%; OR 4.66, 95%CI 3.50-6.20), NSD (20.6%; OR 3.96, 95%CI 2.95-5.32) and IC (33.3%; OR 2.11, 95%CI 1.10-4.04). The CF of PS, NSD and SD cases was respectively 57% (95%CI 54-60%), 60% (95%CI 58-63%) and 93% (95%CI 89-96%). CRC mortality dropped from 40.7 to 25.6\100,000.

CONCLUSION

The program significantly improved the prognosis of patients, decreasing CRC mortality and incidence of advanced CRCs.

The diagnostic accuracy of the faecal immunohistochemical test in identifying significant bowel disease in a symptomatic population

AIM

Provisional research on the faecal immunohistochemical test (FIT) for symptomatic colorectal patients has shown a high negative predictive value but has lacked long-term patient follow-up, raising the possibility of missed diagnoses of colorectal cancer (CRC). The aim of this work is to describe the long-term diagnostic accuracy of the FIT for CRC and significant bowel disease (SBD) in a symptomatic population in NHS Lanarkshire.

METHOD

From October 2016 to February 2019, all primary care referrals of symptomatic colorectal patients in NHS Lanarkshire were asked to provide a FIT. The baseline demographics, investigations and diagnoses for each patient were prospectively completed until February 2021. A FIT result of ≥10 μg haemoglobin (Hb)/g faeces was considered to be positive.

RESULTS

A total of 5250 patients were identified (median age 62 years; 46% male; median follow-up 31 months) with 65.1% (3418) being FIT negative. The SBD rate was 6.2% and the CRC rate was 2.9% (151). The SBD rate was significantly higher in the FIT-positive group (13.8% vs. 2.2%; p < 0.001) and 32.9% of patients with FIT ≥ 400 μg Hb/g had SBD. The sensitivity of FIT ≥ 10 μg Hb/g for CRC was 87.4% and for SBD it was 76.9%. Specificity was 66.6% and 66.7%, and the negative-predictive value was 99.4% and 97.7%, respectively. Sensitivity for CRC could theoretically be increased to 94.8% if FIT-negative patients were to undergo flexible sigmoidoscopy.

CONCLUSION

A FIT-only referral pathway for symptomatic colorectal patients will miss over 12% of cancers and over 23% of SBD. Theoretically, combining FIT-negative patients with flexible sigmoidoscopy increases the sensitivity for CRC. The FIT offers a mechanism for prioritizing patient access to investigations, particularly in resource-limited areas; however, further work to identify FIT-negative patients diagnosed with CRC is required.

Optimizing the colorectal cancer screening programme using faecal immunochemical test (FIT) in Flanders, Belgium from the “interval cancer” perspective

Background

Interval cancer (IC) is a critical issue in colorectal cancer (CRC) screening. We identified factors associated with ICs after faecal immunochemical test (FIT) screening and explored the impact of lowering FIT cut-off or shortening screening interval on FIT-ICs in Flanders.

Methods

FIT participants diagnosed with a CRC during 2013–2018 were included. Factors associated with FIT-ICs were identified using logistic regression. Distributions of FIT results among FIT-ICs were examined.

Results

In total, 10,122 screen-detected CRCs and 1534 FIT-ICs were included (FIT-IC proportion of 13%). FIT-ICs occurred more frequently in women (OR 1.58 [95% CI 1.41–1.76]) and ages 70–74 (OR 1.35 [1.14–1.59]). FIT-ICs were more often right-sided (OR 3.53 [2.98–4.20]), advanced stage (stage IV: OR 7.15 [5.76–8.88]), and high grade (poorly/undifferentiated: OR 2.57 [2.08–3.18]). The majority (83–92%) of FIT-ICs would still be missed if FIT cut-off was lowered from 15 to 10 µg Hb/g or screening interval was shortened from 2 to 1 year.

Conclusions

FIT-ICs were more common in women, older age, right-sided location, advanced stage and high grade. In Flanders, lowering FIT cut-off (to 10 µg Hb/g) or shortening screening interval (to 1 year) would have a minimal impact on FIT-ICs.

Significant decrease in interval colorectal cancer incidence after implementing immunochemical testing in a multiple-round guaiac-based screening programme

BACKGROUND AND AIMS

We aimed to evaluate the effects of switching to faecal immunochemical testing (FIT) on the cumulative 2-year incidence rate of interval cancers, interval cancer rate and test sensitivity within a mature population-based colorectal cancer screening programme consisting of six rounds of biennial guaiac faecal occult blood testing (gFOBT).

METHODS

The FIT results were compared with those of gFOBT used in each of the previous two rounds. For the three rounds analysed, 279,041 tests were performed by 156,186 individuals. Logistic regression analysis was used to determine interval cancer risk factors (Poisson regression) and to compare the sensitivity of FIT to gFOBT.

RESULTS

There were 612 cases of screen-detected cancers and 209 cases of interval cancers. The sex- and age-adjusted cumulative 2-year incidence rates of interval cancers were 55.7 (95% CI, 45.3-68.5), 42.4 (95% CI, 32.6-55.2) and 15.8 (95% CI, 10.9-22.8) per 100,000 person-years after the last two rounds of gFOBT and FIT, respectively. The FIT/gFOBT incidence rate ratio was 0.38 [95% CI, 0.27-0.54] (P < 0.001). Sex- and age-adjusted sensitivity was significantly higher with FIT than with gFOBT (OR = 6.70 [95% CI, 4.48-10.01], P < 0.0001).

CONCLUSIONS

This population-based study revealed a dramatic decrease in the cumulative incidence rates of interval cancers after switching from gFOBT to FIT. These data provide an additional incentive for countries still using gFOBT to switch to FIT.

Screening for Colorectal Cancer: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Colorectal cancer (CRC) remains a significant cause of morbidity and mortality in the US.

OBJECTIVE

To systematically review the effectiveness, test accuracy, and harms of screening for CRC to inform the US Preventive Services Task Force.

DATA SOURCES

MEDLINE, PubMed, and the Cochrane Central Register of Controlled Trials for relevant studies published from January 1, 2015, to December 4, 2019; surveillance through March 26, 2021.

STUDY SELECTION

English-language studies conducted in asymptomatic populations at general risk of CRC.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently appraised the articles and extracted relevant study data from fair- or good-quality studies. Random-effects meta-analyses were conducted.

MAIN OUTCOMES AND MEASURES

Colorectal cancer incidence and mortality, test accuracy in detecting cancers or adenomas, and serious adverse events.

RESULTS

The review included 33 studies (n = 10 776 276) on the effectiveness of screening, 59 (n = 3 491 045) on the test performance of screening tests, and 131 (n = 26 987 366) on the harms of screening. In randomized clinical trials (4 trials, n = 458 002), intention to screen with 1- or 2-time flexible sigmoidoscopy vs no screening was associated with a decrease in CRC-specific mortality (incidence rate ratio, 0.74 [95% CI, 0.68-0.80]). Annual or biennial guaiac fecal occult blood test (gFOBT) vs no screening (5 trials, n = 419 966) was associated with a reduction of CRC-specific mortality after 2 to 9 rounds of screening (relative risk at 19.5 years, 0.91 [95% CI, 0.84-0.98]; relative risk at 30 years, 0.78 [95% CI, 0.65-0.93]). In observational studies, receipt of screening colonoscopy (2 studies, n = 436 927) or fecal immunochemical test (FIT) (1 study, n = 5.4 million) vs no screening was associated with lower risk of CRC incidence or mortality. Nine studies (n = 6497) evaluated the test accuracy of screening computed tomography (CT) colonography, 4 of which also reported the test accuracy of colonoscopy; pooled sensitivity to detect adenomas 6 mm or larger was similar between CT colonography with bowel prep (0.86) and colonoscopy (0.89). In pooled values, commonly evaluated FITs (14 studies, n = 45 403) (sensitivity, 0.74; specificity, 0.94) and stool DNA with FIT (4 studies, n = 12 424) (sensitivity, 0.93; specificity, 0.85) performed better than high-sensitivity gFOBT (2 studies, n = 3503) (sensitivity, 0.50-0.75; specificity, 0.96-0.98) to detect cancers. Serious harms of screening colonoscopy included perforations (3.1/10 000 procedures) and major bleeding (14.6/10 000 procedures). CT colonography may have harms resulting from low-dose ionizing radiation. It is unclear if detection of extracolonic findings on CT colonography is a net benefit or harm.

CONCLUSIONS AND RELEVANCE

There are several options to screen for colorectal cancer, each with a different level of evidence demonstrating its ability to reduce cancer mortality, its ability to detect cancer or precursor lesions, and its risk of harms.

Future Prospects of Colorectal Cancer Screening: Characterizing Interval Cancers

Tumors that are not detected by screening tests are known as interval cancers and are diagnosed clinically after a negative result in the screening episode but before the next screening invitation. Clinical characteristics associated with interval colorectal cancers have been studied, but few molecular data are available that describe interval colorectal cancers. A better understanding of the clinical and biological characteristics associated with interval colorectal cancer may provide new insights into how to prevent this disease more effectively. This review aimed to summarize the current literature concerning interval colorectal cancer and its epidemiological, clinical, and molecular features.

Sudden PSA rise to ≥20 ng/ml and prostate cancer diagnosis in the United States: A population-based study

PURPOSE

While prostate-specific antigen (PSA) screening protocols vary, many clinicians have anecdotes of screened men with low PSA levels that rise significantly and are associated with high-risk prostate cancer (PC). We sought to better understand the frequency of high-risk cases that appear suddenly in a screened population.

METHODS

We utilized data from a Commercial and Medicare advantage claims database to identify all US men ages 50 and above undergoing PSA screening who then had a sudden interval rise in PSA (e.g., PSA ≥ 20) and diagnosis of PC. We determined associations with age, race, screening intensity, and baseline PSA levels.

RESULTS

In all, 526,120 men met entry criteria with an average age of 60.7 and follow-up of 5.6 years. As the baseline PSA increased, the rate of high-risk PC increased from 2/10,000 persons among men with the lowest baseline PSA (<1 ng/ml) to 14/10,000 person-years among men with a baseline PSA < 5 ng/ml. Moreover, as a man's age at baseline PSA increased, the rate of high-risk PC also increased. In contrast, the incidence of high-risk PC did not vary significantly by race/ethnicity. More screening PSAs and shorter intervals between PSA screenings were associated with a lower incidence of high-risk PC.

CONCLUSIONS

The incidence of high-risk PC in a screened population is low (<0.1%). Our findings suggest that systematic screening cannot eliminate all PC deaths and provide an estimate for the risk of the rapid development of high-risk cancers that is comparable to that observed in active surveillance populations.

Curriculum for optical diagnosis training in Europe: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement

This manuscript represents an official Position Statement of the European Society of Gastrointestinal Endoscopy (ESGE) aiming to guide general gastroenterologists to develop and maintain skills in optical diagnosis during endoscopy. In general, this requires additional training beyond the core curriculum currently provided in each country. In this context, ESGE have developed a European core curriculum for optical diagnosis practice across Europe for high quality optical diagnosis training. 1:  ESGE suggests that every endoscopist should have achieved general competence in upper and/or lower gastrointestinal (UGI/LGI) endoscopy before commencing training in optical diagnosis of the UGI/LGI tract, meaning personal experience of at least 300 UGI and/or 300 LGI endoscopies and meeting the ESGE quality measures for UGI/LGI endoscopy. ESGE suggests that every endoscopist should be able and competent to perform UGI/LGI endoscopy with high definition white light combined with virtual and/or dye-based chromoendoscopy before commencing training in optical diagnosis. 2:  ESGE suggests competency in optical diagnosis can be learned by attending a validated optical diagnosis training course based on a validated classification, and self-learning with a minimum number of lesions. If no validated training course is available, optical diagnosis can only be learned by attending a non-validated onsite training course and self-learning with a minimum number of lesions. 3:  ESGE suggests endoscopists are competent in optical diagnosis after meeting the pre-adoption and learning criteria, and meeting competence thresholds by assessing a minimum number of lesions prospectively during real-time endoscopy. ESGE suggests ongoing in vivo practice by endoscopists to maintain competence in optical diagnosis. If a competent endoscopist does not perform in vivo optical diagnosis on a regular basis, ESGE suggests repeating the learning and competence phases to maintain competence.Key areas of interest were optical diagnosis training in Barrett's esophagus, esophageal squamous cell carcinoma, early gastric cancer, diminutive colorectal lesions, early colorectal cancer, and neoplasia in inflammatory bowel disease. Condition-specific recommendations are provided in the main document.

Colorectal Cancer Survival in 50- to 69-Year-Olds after Introducing the Faecal Immunochemical Test

Population screening has improved early diagnosis of colorectal cancer (CRC). Nonetheless, most cases are diagnosed in symptomatic patients. Faecal immunochemical testing has been recommended for assessing patients with lower gastrointestinal symptoms, but whether it improves patient survival is unknown. Our objective was to compare CRC survival in 50- to 69-year-olds between asymptomatic screen-detected patients and symptomatic patients by route to diagnosis. Methods: We identified all cases of CRC diagnosed in 50-to 69-year-olds between 2009 and 2016, in Donostialdea (Gipuzkoa, Spain). Three groups were created: 1-screen-detected CRC; 2-CRC detected in symptomatic patients after a positive faecal immunochemical test(FIT); and 3-CRC detected in symptomatic patients without a FIT or after a negative result. We analysed survival using the Kaplan-Meier method and log-rank tests. Results: Of 930 patients diagnosed with CRC, 433 cases were detected through screening and 497 in symptomatic patients, 7.9% after a positive FIT and 45.5% by other means. The 3-year CRC survival was significantly lower in group 3 (69.5%) than groups 1 (93%; p = 0.007) or 2 (87.5%; p = 0.02). The risk of death was lower in groups 1 (HR 0.42, 95% CI 0.30–0.58) and 2 (HR 0.51; 95% CI 0.29–0.87). Conclusion: Half of CRC cases in 50- to 69-year-olds are diagnosed outside screening. Use of the FIT as a diagnostic strategy in symptomatic patients may improve survival.

Incidence of Interval Colorectal Cancer After Negative Results From First-Round Fecal Immunochemical Screening Tests, by Cutoff Value and Participant Sex and Age

BACKGROUND & AIMS

We evaluated the incidence of interval cancers between the first and second rounds of colorectal cancer (CRC) screening with the FOB-Gold fecal immunochemical test (FIT), and the effects of different cutoff values and patient sex and age.

METHODS

We collected data from participants in a population-based CRC screening program in the Netherlands who had a negative result from a first-round of FIT screening. We calculated the cumulative incidence of interval cancer after a negative result from a FIT and the sensitivity of the FIT for detection of CRC at a low (15 μg Hb/g feces) and high (47 μg Hb/g feces) cutoff value.

RESULTS

Among the 485,112 participants with a negative result from a FIT, 544 interval cancers were detected; 126 were in the 111,800 participants with negative results from a FIT with the low cutoff value and 418 were in the 373,312 FIT participants with negative results from a FIT with the high cutoff value. The mean age of participants tested with the low cutoff value was 72.0 years and the mean age of participants tested the high cutoff value was 66.7 years. The age-adjusted 2-year cumulative incidence of interval cancer after a negative result from a FIT were 9.5 per 10,000 persons at the low cutoff value vs 13.8 per 10,000 persons at the high cutoff value (P < .005). The age-adjusted sensitivity of the FIT for CRC were 90.5% for the low cutoff value vs 82.9% for the high cutoff (P < .0001). The FIT identified men with CRC with 87.4% sensitivity and women with CRC with 82.6% sensitivity (P < .001).

CONCLUSIONS

In an analysis of data from a FIT population-based screening program in the Netherlands, we found that incidence of interval CRC after a negative result from a FIT to be low. Although the sensitivity of detection of CRC decreased with a higher FIT cutoff value, it remained above 80%.

Interval colorectal cancers after negative faecal immunochemical test in a 13-year screening programme

OBJECTIVE

To assess faecal immunochemical test sensitivity for cancer in a very large population-based cohort followed up for six rounds with biennial faecal immunochemical test repetition.

METHODS

This study is based on interval colorectal cancers diagnosed in a cohort of subjects aged 50-69 undergoing repeated faecal immunochemical test screening (six rounds) from 2002 to 2015. Test sensitivity was calculated using both the Proportional Interval Cancer Rate and the Interval Cancer Proportion method.

RESULTS

Among 441,647 faecal immunochemical tests (123,347 individuals), 150 interval colorectal cancers were detected after a negative faecal immunochemical test. Interval colorectal cancer incidence rate was 1.87 per 10,000 person-years (95%CI: 1.60-2.20), and it was higher during the second interval year (rate ratio: 1.78; 95%CI: 1.28-2.47), for proximal locations (rate ratio: 3.00; 95%CI: 1.92-4.68), and among 60-71 year old subjects (rate ratio: 2.37; 95%CI: 1.61-3.50). The Proportional Interval Cancer Rate was 13.1%, with an overall faecal immunochemical test sensitivity of 86.9% (95%CI: 84.7-89.0). Sensitivity was lowest at the first round (81.5%; 95%CI: 75.6-86.2), and increased to 91.9% (95%CI: 83.9-96.5) for subsequent rounds. Applying the Interval Cancer Proportion method, sensitivity was 83.9% (95%CI: 81.3-86.2), and it was highest at the first round (89.0%; 95%CI: 85.7-91.6), ranging between 73% and 83.1% at subsequent rounds.

CONCLUSIONS

A faecal immunochemical test sensitivity for cancer higher than 80% resulted in a low incidence of interval colorectal cancers, representing an accurate estimate of one of the major limits of screening programmes. Due to intrinsic biases, the Proportional Interval Cancer Rate and the Interval Cancer Proportion methods generated different trends in faecal immunochemical test sensitivity by screening round.

The cumulative false-positive rate in colorectal cancer screening: a Markov analysis

BACKGROUND

Faecal occult blood testing is widely used in colorectal cancer screening. However, there is little empirical long-term evidence on the accumulation of false-positive test results over several screening rounds. We aimed to systematically explore and quantify the cumulative false-positive rate for various scenarios of colorectal cancer screening.

METHODS

Using a Markov analysis, we estimated the lifetime cumulative number of false-positive test results (cumFP) per 100 000 50-year-old persons. We varied the screening interval and the specificity of a single screening test and the starting age of screening.

RESULTS

For a test with a specificity of 98% used from 50 to 74 years, the cumFP at age 74 was 26 260 (1-year interval), 15 102 (2-year interval), and 10 819 (3-year interval), respectively. For a test with a specificity of, respectively, 95 and 92% used at a 2-year interval, the cumFP at age 74 was 2.2 times and 3.0 times higher as compared to a test with a specificity of 98%. The cumFP at age 74 was 18% lower for screening persons aged 54-74 years vs. 50-74 years.

CONCLUSION

Our findings quantitatively illustrate the large variation of the cumFP in colorectal cancer screening between screening strategies, which is relevant to informed decision making and adequate resource planning.

Diagnostic Yield of One-Time Colonoscopy vs One-Time Flexible Sigmoidoscopy vs Multiple Rounds of Mailed Fecal Immunohistochemical Tests in Colorectal Cancer Screening

BACKGROUND & AIMS

We compared the diagnostic yields of colonoscopy, flexible sigmoidoscopy, and fecal immunochemical tests (FITs) in colorectal cancer (CRC) screening.

METHODS

A total of 30,007 asymptomatic persons, 50-74 years old, were invited for CRC screening in the Netherlands. Participants were assigned to groups that received 4 rounds of FIT (mailed to 15,046 participants), once-only flexible sigmoidoscopy (n = 8407), or once-only colonoscopy (n = 6600). Patients with positive results from the FIT (≥10 μg Hb/g feces) were referred for colonoscopy. Patients who underwent flexible sigmoidoscopy were referred for colonoscopy if they had a polyp of ≥10 mm; adenoma with ≥25% villous histology or high-grade dysplasia; sessile serrated adenoma; ≥3 adenomas; ≥20 hyperplastic polyps; or invasive CRC. The primary outcome was number of advanced neoplasia detected (diagnostic yield) by each test. Secondary outcomes were number of colonoscopies needed to detect advanced neoplasia and number of interval CRCs found during each primary screening test. Patients with interval CRCs were found through linkage with Netherlands Cancer Registry. Advanced neoplasia were defined as CRC, adenomas ≥ 10 mm, adenomas with high-grade dysplasia, or adenomas with a villous component of at least 25%.

RESULTS

The cumulative participation rate was significantly higher for FIT screening (73%) than for flexible sigmoidoscopy (31%; P < .001) or colonoscopy (24%; P < .001). The percentage of colonoscopies among invitees was higher for colonoscopy (24%) compared to FIT (13%; P < .001) or flexible sigmoidoscopy (3%; P < .001). In the intention to screen analysis, the cumulative diagnostic yield of advanced neoplasia was higher with FIT screening (4.5%; 95% CI 4.2-4.9) than with colonoscopy (2.2%; 95% CI, 1.8-2.6) or flexible sigmoidoscopy (2.3%; 95% CI, 2.0-2.7). In the as-screened analysis, the cumulative yield of advanced neoplasia was higher for endoscopic screening with colonoscopy (9.1%; 95% CI, 7.7-10.7) or flexible sigmoidoscopy (7.4%; 95% CI, 6.5-8.5) than with the FIT (6.1%; 95% CI, 5.7-6.6). All 3 screening strategies detected a similar proportion of patients with CRC. Follow-up times differed for each test (median 8.3 years for FIT and flexible sigmoidoscopy and 5.8 years for colonoscopy). Proportions of patients that developed interval CRC were 0.13% for persons with a negative result from FIT, 0.09% for persons with a negative result from flexible sigmoidoscopy, and 0.01% for persons with a negative result from colonoscopy.

CONCLUSIONS

Mailed multiple-round FITs detect significantly more advanced neoplasia, on a population level, compared with once-only flexible sigmoidoscopy or colonoscopy screening. Significantly fewer colonoscopies are required by individuals screened by multiple FITs. Trialregister.nl numbers: first round, NTR1096; second round and additional invitees, NTR1512; fourth round, NTR5874; COCOS trial NTR1829.

Benefits of switching from guaiac-based faecal occult blood to faecal immunochemical testing: experience from the Wallonia-Brussels colorectal cancer screening programme

Background

Faecal immunochemical tests (FITs) have replaced guaiac-based faecal occult blood test (gFOBTs) in several colorectal cancer (CRC) screening programmes. We aimed to evaluate the benefits of this transition based on the Wallonia–Brussels-organised CRC screening programme.

Methods

A total of 1,569,868 individuals aged 50–74 years, who were invited to screening during 2009–2017, were studied by linking their screening records with insurance, pathology and cancer data in the Belgian Cancer Registry. We compared neoplasm detection rates and positive predictive values (PPVs) of gFOBT and FIT at 15 µg haemoglobin per gram cut-off in screen-naive individuals. We furthermore examined the incidence rates of interval cancer in gFOBT- and FIT-based screening programme.

Results

Advanced neoplasms were detected less frequently by gFOBT (0.8%) than by FIT (1.3%), with a difference of 0.5% (P < 0.01). PPVs were lower for gFOBT (15.1%) than for FIT (21.7%) for advanced neoplasms (difference 6.6%, P < 0.01). Compared to participants with negative gFOBT, those with negative FIT were 77% less likely to develop interval cancer (incidence rate ratio 0.23, 95% confidence interval 0.16–0.33).

Conclusion

Our study demonstrated that in an organised CRC screening programme, replacing gFOBT with FIT improved neoplasm detection rate and substantially reduced interval cancer incidence.

Characteristics of Advanced Colorectal Cancer Detected by Fecal Immunochemical Test Screening in Participants with a Negative Result the Previous Year

BACKGROUND

There is sufficient evidence to show the mortality reduction effect of colorectal cancer (CRC) screening programs using the fecal occult blood test (FOBT). However, we see cases that are found to be advanced CRC despite yearly FOBT screening.

METHODS

The aim of this study was to investigate the characteristics of advanced CRC detected by a fecal immunochemical test (FIT) screening program in participants with a negative screening result the previous year, which we call "Negative advanced CRC". A total of 109,639 participants (10.0% required colonoscopy, of whom 76.9% received one) underwent a CRC screening program using a FIT from fiscal 2009 to 2017. Negative advanced CRC was compared with advanced CRC (First advanced CRC) found at the first visit in a person who had not had a FIT screening history for more than 3 years. In addition, we compared the characteristics of Negative advanced CRC with those of interval cancer: cancer cases detected after a negative screening result and before the date of the next recommended screening.

RESULTS

A total of 339 cases of CRC (175 male: 164 female, 173 early stage: 166 advanced stage) were detected in the nine-year CRC screening period. The rate of right-sided CRCs was significantly higher in female (P < 0.01), advanced stage (P < 0.01), negative result previous year (P < 0.01), and symptom-negative (P < 0.01) participants than in each counterpart, respectively. The ratio of female (22/35; 62.9%) patients in Negative advanced CRCs tended to be high compared with that (40/83; 48.2%) in First advanced CRCs (P = 0.145). Overall, 22 (62.9%) of 35 Negative advanced CRCs and 28 (33.7%) of 83 First advanced CRCs were located in the right-sided colon, and the rate was significantly higher in Negative advanced CRCs (P < 0.01). In addition, the frequency of female patients was significantly higher in right-sided Negative advanced CRCs than in right-sided First advanced CRCs (P = 0.03).

CONCLUSION

The characteristics of Negative advanced CRC cases (female and right-sided colon) were similar to those of interval cancer reported so far. In the future, it will be necessary to introduce a screening program that is highly sensitive to right-sided CRC.

Effect of Sex, Age, and Positivity Threshold on Fecal Immunochemical Test Accuracy: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Quantitative fecal immunochemical tests (FITs) for hemoglobin are commonly used for colorectal cancer (CRC) screening. We aimed to quantify the change in CRC and advanced adenoma detection and number of positive test results at different positivity thresholds and by sex and age.

METHODS

We searched MEDLINE and EMBASE, selecting articles of FIT for CRC detection in asymptomatic adults undergoing screening. We calculated sensitivity and specificity, as well as detected number of cancers, advanced adenomas, and positive test results at positivity thresholds ≤10 μg hemoglobin/g feces, 10 to ≤20 μg/g, 20 to ≤30 μg/g, and >30 μg/g. We also analyzed results from stratified by patient sex, age, and reference standard.

RESULTS

Our meta-analysis comprised 46 studies with 2.4 million participants and 6478 detected cancers. Sensitivity for detection of CRC increased from 69% (95% confidence interval [CI], 63%-75%) at thresholds >10 μg/g and ≤20 μg/g to 80% (95% CI, 76%-83%) at thresholds ≤10 μg/g. At these threshold values, sensitivity for detection of advanced adenomas increased from 21% (95% CI, 18%-25%) to 31% (95% CI, 27%-35%), whereas specificity decreased from 94% (95% CI, 93%-96%) to 91% (95% CI, 89%-93%). In 3 studies stratified by sex, sensitivity of CRC detection was 77% in men (95% CI, 75%-79%) and 81% in women (95% CI, 60%-100%) (P = .68). In 3 studies stratified by age groups, sensitivity of CRC detection was 85% for ages 50-59 years (95% CI, 71%-99%) and 73% for ages 60-69 years (95% CI, 71%-75%) (P = .10). All studies with colonoscopy follow-up had similar sensitivity levels for detection of CRC to studies that analyzed 2-year registry follow-up data (74%; 95% CI, 68%-78% vs 75%; 95% CI, 73%-77%).

CONCLUSIONS

In a meta-analysis of studies that analyzed detection of CRC and advanced adenomas at different FIT positivity thresholds, we found the sensitivity and specificity of detection to vary with positive cutoff value. It might be possible to decrease positive threshold values for centers with sufficient follow-up colonoscopy resources. More research is needed to precisely establish FIT thresholds for each sex and age subgroup.

PROTOCOL

PROSPERO CRD42017068760.

Occurrence and characteristics of faecal immunochemical screen-detected cancers vs non-screen-detected cancers: Results from a Flemish colorectal cancer screening programme

BACKGROUND

Colorectal cancer (CRC) and its precursor lesions are detected at an early stage by CRC screening programmes, which reduce CRC-related mortality. An important quality indicator for CRC screening is the occurrence of interval CRC (IC) between screening rounds. Currently there is no guideline regarding acceptable levels of ICs in CRC screening programmes, and ICs reported in prior work vary considerably.

METHODS

This study describes the occurrence of screen-detected (SD) CRC and non-screen-detected CRC within the population-based CRC screening programme of Flanders, stratified by multiple variables such as sex, age, tumour location and tumour stage between October 2013 and July 2017. In addition, faecal immunochemical test (FIT) IC proportions over the sum of SD-CRCs and FIT-ICs are calculated, together with FIT sensitivity and programme sensitivity to display the effectiveness of detecting CRC by the screening programme.

RESULTS

Of 1,212,354 FIT participants, 4094 were diagnosed with SD-CRC, whereas 772 participants were diagnosed with CRC between FIT-screening rounds. Significant associations were shown between people not being SD for CRC and women, older individuals, right-sided tumour location and more advanced tumour stage. Furthermore, a clear distinction was shown between the right-sided and the left-sided colorectum concerning all above-mentioned variables and distributions of tumour stages.

CONCLUSION

The Flemish FIT-interval CRC proportion of 15.9% was within the limits of previously published results. In addition, calculations show that the effectiveness of the screening programme is dependent on tumour location, suggesting that future research should report results stratified by location.

Towards risk-stratified colorectal cancer screening. Adding risk factors to the fecal immunochemical test: Evidence, evolution and expectations

With increasing incidence and mortality, colorectal cancer (CRC) is a growing health problem worldwide. An effective way to address CRC is by screening for fecal (occult) blood by the fecal immunochemical test (FIT). However, there is room for improvement since precursor lesions and CRC bleed intermittent and can therefore be missed by the FIT (false negatives) or, the detected blood did not result from precursor lesions or CRC (false positives). This review provides the latest evidence on risk prediction models using FIT combined with additional risk factors before colonoscopy, which risk factors to include and if these models will better discriminate between normal findings and CRC compared to the FIT-only. Many prediction models are known for CRC, but compared to the FIT, these are less effective in detecting CRC. The literature search resulted in 645 titles where 11 papers matched the inclusion criteria and were analyzed. Comparing the FIT-only with the risk prediction models for detecting CRC resulted in a significantly increased discrimination for the models. In addition, 2 different risk-stratification categories before colonoscopy were distinguished, namely the 1-model approach which combined risk factors with FIT results in a prediction model while the 2 step approach used risk factors apart from the FIT. Finally, combining FIT with CRC risk factors by means of a model before colonoscopy seems effective regarding discriminative power, however, more research is needed for validation combined with transparent and standardized reporting to improve quality assessment, for which suggestions are reported in this study.

Multiple rounds of one sample versus two sample faecal immunochemical test-based colorectal cancer screening: a population-based study

BACKGROUND

Faecal immunochemical test (FIT)-based colorectal cancer screening requires successive rounds for maximum preventive effect. Advanced neoplasia can bleed intermittently and thus might be missed by single faecal sampling. Few studies have been done on two sample FIT (2-FIT) screening over multiple rounds. Therefore, we compared multiple rounds of one sample FIT (1-FIT) with 2-FIT screening with respect to participation, positive predictive value (PPV), diagnostic yield, and interval colorectal cancer.

METHODS

In this population-based study, a random selection of asymptomatic individuals aged 50-74 years in the Rotterdam-Rijnmond region, Netherlands, were invited by post for four rounds (every 2 years) of 1-FIT or 2-FIT screening. Key exclusion criteria were a history or colorectal cancer or inflammatory bowel disease, colon imaging in the previous 2 years, and life expectancy of less than 5 years. Per round, invitees received one or two FITs to sample either one or two consecutive bowel movements. OC-Sensor Micro (Eiken Chemical Co., Ltd, Japan) FITs were used by all participants, except the fourth round of screening for the 1-FIT cohort, for which participants used either an OC-Sensor or a FOB-Gold (Sentinel Diagnostics, Milan, Italy). A faecal haemoglobin cutoff concentration of 10 μg/g of faeces in at least one test was used for referral for colonoscopy.

FINDINGS

Between 2006 and 2015, of 10 008 invited individuals for the 1-FIT cohort, 9787 were eligible for inclusion, of whom 7310 participated at least once in four successive rounds. Of 3197 invited individuals for the 2-FIT cohort, 3131 were eligible for inclusion, and 2269 participated at least once in four successive rounds. In the 1-FIT screening cohort, 74·7% (7310 of 9787) of invitees participated at least once versus 72·5% (2269 of 3131) of invitees in the 2-FIT cohort (p=0·013). Among participants who participated at least once, the cumulative positivity rate over four rounds was 19·2% (1407 of 7310) for the 1-FIT cohort versus 28·5% (647 of 2269) for the 2-FIT cohort (p<0·0001). The cumulative PPV for advanced neoplasia was 33·0% (432 of 1308 colonoscopies) for the 1-FIT cohort versus 24·2% (147 of 607 colonoscopies) for the 2-FIT cohort (p<0·0001). The cumulative diagnostic yield of advanced neoplasia among invited individuals was 4·4% (432 of 9787) for 1-FIT versus 4·7% (147 of 3131) for 2-FIT screening (p=0·46)). FIT interval colorectal cancers were detected in eight (0·1%) of 7310 participants in the 1-FIT cohort and two (0·1%) of 2269 with 2-FIT screening (p=1·00).

INTERPRETATION

Four rounds of 2-FIT screening with a low faecal haemoglobin cutoff level did not result in a significant increase in diagnostic yield or a decrease in interval colorectal cancers compared with 1-FIT, despite higher colonoscopy demand. Therefore, 1-FIT colorectal cancer screening programmes should be preferred.

FUNDING

None.

Incidence of faecal occult blood test interval cancers in population-based colorectal cancer screening: a systematic review and meta-analysis

OBJECTIVE

Faecal immunochemical tests (FITs) are replacing guaiac faecal occult blood tests (gFOBTs) for colorectal cancer (CRC) screening. Incidence of interval colorectal cancer (iCRC) following a negative stool test result is not yet known. We aimed to compare incidence of iCRC following a negative FIT or gFOBT.

DESIGN

We searched Ovid Medline, Embase, Cochrane Library, Science Citation Index, PubMed and Google Scholar from inception to 12 December 2017 for citations related to CRC screening based on stool tests. We included studies on FIT or gFOBT iCRC in average-risk screening populations. Main outcome was pooled incidence rate of iCRCs per 100 000 person-years (p-y). Pooled incidence rates were obtained by fitting random-effect Poisson regression models.

RESULTS

We identified 7 426 records and included 29 studies. Meta-analyses comprised data of 6 987 825 subjects with a negative test result, in whom 11 932 screen-detected CRCs and 5 548 gFOBT or FIT iCRCs were documented. Median faecal haemoglobin (Hb) positivity cut-off used was 20 (range 10-200) µg Hb/g faeces in the 17 studies that provided FIT results. Pooled incidence rates of iCRC following FIT and gFOBT were 20 (95% CI 14 to 29; I²=99%) and 34 (95% CI 20 to 57; I²=99%) per 100 000 p-y, respectively. Pooled incidence rate ratio of FIT versus gFOBT iCRC was 0.58 (95% CI 0.32 to 1.07; I²=99%) and 0.36 (95% CI 0.17 to 0.75; I²=10%) in sensitivity analysis. For every FIT iCRC, 2.6 screen-detected CRCs were found (ratio 1:2.6); for gFOBT, the ratio between iCRC and screen-detected CRC was 1:1.2. Age below 60 years and the third screening round were significantly associated with a lower iCRC rate.

CONCLUSION

A negative gFOBT result is associated with a higher iCRC incidence than a negative FIT. This supports the use of FIT over gFOBT as CRC screening tool.

The future of surgical oncology

Fast moving specialty

Viewpoints of the target population regarding barriers and facilitators of colorectal cancer screening in the Czech Republic

BACKGROUND

Public awareness of colorectal cancer (CRC) and uptake of CRC screening remain challenges. The viewpoints of the target population (asymptomatic individuals older than 50) regarding CRC screening information sources and the reasons for and against participation in CRC screening are not well known in the Czech Republic. This study aimed to acquire independent opinions from the target population independently on the health system.

AIM

To investigate the viewpoints of the target population regarding the source of information for and barriers and facilitators of CRC screening.

METHODS

A survey among relatives (aged 50 and older) of university students was conducted. Participants answered a questionnaire about sources of awareness regarding CRC screening, reasons for and against participation, and suggestions for improvements in CRC screening. The effect of certain variables on participation in CRC screening was analyzed.

RESULTS

Of 498 participants, 478 (96%) respondents had some information about CRC screening and 375 (75.3%) had participated in a CRC screening test. General practitioners (GPs) (n = 319, 64.1%) and traditional media (n = 166, 33.3%) were the most common information sources regarding CRC screening. A lack of interest or time and a fear of colonoscopy or positive results were reported as reasons for non-participation. Individuals aged > 60 years [adjusted odds ratio (aOR) = 2.30, 95% confidence interval (CI) (1.42-3.71), P = 0.001], females (aOR = 1.95, 95%CI (1.26-3.01) P = 0.003), and relatives of CRC patients (aOR = 4.17, 95%CI (1.82-9.58) P = 0.001) were more likely to participate in screening. Information regarding screening provided by physicians - GPs: (aOR = 8.11, 95%CI (4.90-13.41), P < 0.001) and other specialists (aOR = 4.19, 95%CI (1.87-9.38), P = 0.001) increased participation in screening. Respondents suggested that providing better explanations regarding screening procedures and equipment for stool capturing could improve CRC screening uptake.

CONCLUSION

GPs and other specialists play crucial roles in the successful uptake of CRC screening. Reduction of the fear of colonoscopy and simple equipment for stool sampling might assist in improving the uptake of CRC screening.

Fecal immunochemical test in cancer screening - colonoscopy outcome in FIT positives and negatives

Objectives: Fecal immunochemical test (FIT) is used in colorectal cancer (CRC) screening, but evaluations of multiple sample strategies in colonoscopy screening cohorts are rare. The aim of this study was to assess accuracy of FIT for advanced neoplasia (AN) with two fecal samples in a colonoscopy screening cohort. Materials and methods: The study comprised 1155 participants of the colonoscopy arm in SCREESCO (Screening of Swedish Colons, NCT02078804), a randomized controlled study on CRC screening of 60-year-olds from the Swedish average-risk population. Participants provided two FIT samples prior to colonoscopy. First sample, mean of two, and any of the two samples above cut off level were assessed. Colonoscopy findings (CRC, advanced adenoma (AA), AN (CRC + AA) and adenoma characteristics) were evaluated in uni- and multivariable analysis in relation to FIT positivity (at ≥10 µg hemoglobin (Hb)/g). Results: Of 1155 invited, 806 (416 women, 390 men) participated. CRC, AA and non-AA were found in one (0.1%), 80 (9.9%) and 145 (18%), respectively. Sensitivity and specificity for AN were 20%/93%, 25%/92% and 26%/89% for first, mean of two and any of the two samples respectively at cut off level 10 µg/g, corresponding to 60 (74%)-65 (80%) participants with missed AN. The difference in sensitivity between screening strategies was non-significant. The specificity for first sample was significantly higher than for any of the two samples at cut off 10 µg/g (p = .02) and 20 µg/g (p = .04). FIT positivity in participants with adenoma was associated with pedunculated shape (p = .007) and high-risk dysplasia (p = .009). Conclusions: In an average-risk colonoscopy screening cohort of 60-year-olds, sensitivity for AN was modest and did not increase when using two samples instead of one. FIT predominantly detected adenomas with pedunculated shape and high-risk dysplasia, and participants with flat or broad based adenomas may thus be missed in screening.

Impact of a higher fecal immunochemistry test cut-off on pathology detected in subsequent rounds of a colorectal screening program

BACKGROUND AND AIMS

Fecal immunochemical test (FIT)-based colorectal cancer (CRC) screening is superior to the traditional binary fecal occult blood test. Its quantitative nature allows the investigator to choose a positivity threshold to match cost and endoscope capacity. The optimal threshold is still debated. BowelScreen, the Irish national colorectal cancer screening program, has a cut-off of 45 μg Hb/g feces, and in this study we investigated the impact of this threshold on pathology detected in round 2 in individuals who had a negative result for round 1 FIT (FIT¹).

METHODS

All individuals with a negative FIT¹ result who completed a round 2 FIT (FIT²) 2 years later were included. Pathology outcomes for individuals who had positive FIT² results were correlated with FIT¹ levels.

RESULTS

A total of 37,877 individuals had negative FIT¹ results and completed FIT². One thousand two hundred thirty (3.2%) had positive FIT² results (702 men [57%], median age 69, age range 60-70 years). Quantitative analysis showed that at an FIT¹ level <5 μg Hb/g feces, 2.3% had positive FIT² results. At a higher cut-off of 40.1 to 45 μg Hb/g feces, 15.6% of individuals had positive FIT² results. One thousand two (81.5%) underwent colonoscopy, with clinical outcomes in all cases. Three hundred fifty-one (35%) had normal colonoscopy results. The proportion of individuals with normal colonoscopy results decreased as FIT¹ levels rose. Conversely, advanced pathology (CRC + high-risk adenomas) rates rose from 7% to 50% when FIT¹ was <5 compared with 40.1 to 45 μg Hb/g feces, respectively. There were 51 screen-detected cancers in round 2 among individuals with negative FIT¹ results (22 stage I, 12 stage II, 14 stage III, 3 stage IV). All 3 stage IV individuals had FIT¹ results <20 μg Hb/g feces.

CONCLUSIONS

Varying rates of pathology are observed in round 2 of a screening program based on the quantitative level of a negative round 1 FIT result when the positivity threshold is relatively high. A CRC rate of 5.1% within this group appears acceptable. Although patients with incurable cancer were observed, the positivity threshold to capture these cases within round 1 would have been so sensitive that it would create an unsustainable endoscopy referral burden.

Quality assurance of colonoscopy within the Dutch national colorectal cancer screening program

Colorectal cancer (CRC) screening is capable of reducing CRC-related morbidity and mortality. Colonoscopy is the reference standard to detect CRC, also providing the opportunity to detect and resect its precursor lesions: colorectal polyps. Therefore, colonoscopy is either used as a primary screening tool or as a subsequent procedure after a positive triage test in screening programs based on non-invasive stool testing or sigmoidoscopy. However, in both settings, colonoscopy is not fully protective for the occurrence of post-colonoscopy CRCs (PCCRCs). Because most PCCRCs are the result of colonoscopy-related factors, a high-quality procedure is of paramount importance to assure optimal effectiveness of CRC screening programs. For this reason, at the start of the Dutch fecal immunochemical test (FIT)-based screening program, quality criteria for endoscopists performing colonoscopies in FIT-positive screenees, as well as for endoscopy centers, were defined. In conjunction, an accreditation and auditing system was designed and implemented. In this report, we describe the quality assurance process for endoscopists participating in the Dutch national CRC screening program, including a detailed description of the evidence-based quality criteria. We believe that our experience might serve as an example for colonoscopy quality assurance programs in other CRC screening programs.

Postoperative Outcomes of Screen-Detected vs Non-Screen-Detected Colorectal Cancer in the Netherlands

Importance

The nationwide fecal immunochemical test-based screening program has influenced surgical care for patients with colorectal cancer (CRC) in the Netherlands, although these implications have not been studied in much detail so far.

Objective

To compare surgical outcomes of patients diagnosed as having CRC through the fecal immunochemical test-based screening program (screen detected) and patients with non-screen-detected CRC.

Design, Setting, and Participants

This was a population-based comparative cohort study using the Dutch ColoRectal Audit and analyzed all Dutch hospitals performing CRC resections. Patients who underwent elective resection for CRC between January 2011 to December 2016 were included.

Interventions

Colorectal cancer surgery.

Main Outcomes and Measures

Postoperative nonsurgical complications, postoperative surgical complications, postoperative 30-day or in-hospital mortality, and complicated course (postoperative complication resulting in a hospital stay >14 days and/or a reintervention and/or mortality). A risk-stratified comparison was made for different postoperative outcomes based on screening status (screen detected vs not screen detected), cancer stage (I-IV), and for cancer stage I to III also on age (aged ≤70 years and >70 years) and American Society of Anesthesiologists score (I-II and III-IV). To determine any residual case-mix-corrected differences in outcomes between patients with screen-detected and non-screen-detected cancer, univariable and multivariable logistic regression analyses were performed.

Results

In total, 36 242 patients with colon cancer and 17 416 patients with rectal cancer were included for analysis. Compared with patients with non-screen-detected CRC, screen-detected patients were younger (mean [SD] age, 68 [5] vs 70 [11] years), more often men (3777 [60%] vs 13 506 [57%]), and had lower American Society of Anesthesiologists score (American Society of Anesthesiologists score III+: 838 [13%] vs 5529 [23%]). Patients with stage I to III colon cancer who were screen detected had a significantly lower mortality and complicated course rate compared with non-screen-detected patients. For patients with rectal cancer, only a significant difference was found in mortality rate in patients with a cancer stage IV disease, which was higher in the screen-detected group. Compared with non-screen-detected colon cancer, an independent association was found for screen-detected colon cancer on nonsurgical complications (adjusted odds ratio, 0.81; 95% CI, 0.73-0.91), surgical complications (adjusted odds ratio, 0.80; 95% CI, 0.72-0.89), and complicated course (adjusted odds ratio, 0.80; 95% CI, 0.71-0.90). Screen-detected rectal cancer had significantly higher odds on mortality.

Conclusions and Relevance

Postoperative outcomes were significantly better for patients with colon cancer referred through the fecal immunochemical test-based screening program compared with non-screen-detected patients. These differences were not found in patients with rectal cancer. The outcomes of patients with screen-detected colon cancer were still better after an extensive case-mix correction, implying additional underlying factors favoring patients referred for surgery through the screening program.

The novel latex agglutination turbidimetric immunoassay system for simultaneous measurements of calprotectin and hemoglobin in feces

Background/Aims

Fecal calprotectin (Fcal) as well as the fecal immunochemical test (FIT) are useful biomarkers for detecting activity and mucosal healing in inflammatory bowel diseases. Here, we report the performance of simultaneous measurements of Fcal and FIT for ulcerative colitis (UC) patients using the newly-developed latex agglutination turbidimetric immunoassay (LATIA) system.

Methods

Fcal and hemoglobin were measured by the LATIA system in 152 UC patients who underwent colonoscopy. Fcal was also quantified with a conventional enzyme-linked immunosorbent assay (ELISA). Fecal markers were evaluated in conjunction with the mucosal status of UC, which was assessed via the Mayo endoscopic subscore (MES) classification.

Results

The LATIA system could quantify calprotectin and hemoglobin simultaneously with the same fecal samples within 10 minutes. The values of the Fcal-LATIA closely correlated with those of the Fcal-ELISA (Spearman rank correlation coefficient, r=0.84; P<0.0001). The values of Fcal for each assay and the FIT all significantly correlated with the MESs (Spearman rank correlation coefficient, Fcal-LATIA: r=0.58, Fcal-ELISA: r=0.55, and FIT: r=0.72). The mucosal healing predictability (determined by an MES of 0 alone) of the Fcal-LATIA, Fcal-ELISA, and FIT-LATIA with the cutoffs determined by receiver operating characteristic curve analysis was 0.79, 0.78, and 0.92 for sensitivity, respectively, and 0.78, 0.69, and 0.73 for specificity, respectively.

Conclusions

The performance of the novel Fcal-LATIA was equivalent to that of the conventional Fcal assay. Simultaneous measurements with FITs would promote the clinical relevance of fecal biomarkers in UC.

Participant-Related Risk Factors for False-Positive and False-Negative Fecal Immunochemical Tests in Colorectal Cancer Screening: Systematic Review and Meta-Analysis

OBJECTIVES

Colorectal cancer (CRC) screening using fecal immunochemical tests (FIT) may reduce CRC-related mortality but its effectiveness is influenced by the limited accuracy of FIT. Identifying individuals at increased risk of a false FIT result could improve screening, but the available evidence is conflicting. We performed a systematic review and meta-analysis on risk factors for false-positive and false-negative FIT results in CRC screening.

METHODS

A systematic search in MEDLINE, EMBASE, and Cochrane Library identified publications (before 29 January 2017) on risk factors (known at time of FIT invitation) associated with false FIT results (presence/absence of advanced neoplasia) in a CRC screening setting. Risk of bias was assessed using QUIPS. In meta-analysis, summary relative risk ratios and corresponding 95% confidence intervals were calculated for each risk factor.

RESULTS

Of 518 records identified, 14 studies with 54,499 participants in total were included for analysis. In meta-analysis, male sex was associated with a significantly lower risk of false-positivity (RR 0.84, CI 0.74-0.94), whereas participants using non-steroidal anti-inflammatory drugs (NSAIDs) had a higher risk (RR 1.16, CI 1.06-1.27). The use of anticoagulants was most frequently studied, without a significant effect on FIT positivity. Males (RR 1.83, CI 1.53-2.19), participants with a family history for CRC (RR 1.61, CI 1.19-2.15), hyperglycemia (RR 1.29, CI 1.02-1.65), hypertension (RR 1.50, CI 1.14-1.98), obesity (RR 1.38, CI 1.11-1.71), and (former) smokers (RR 1.93, CI 1.52-2.45) were all at significantly higher risk for false-negative results. Age was not found to have a systematic effect on either FIT false-positivity or false-negativity in meta-analysis.

CONCLUSIONS

Multiple risk factors, known at time of FIT invitation, are associated with false FIT results in CRC screening. This information can be used to identify populations risking false reassurance after a negative result or unnecessary colonoscopy after a positive result, and to further optimize CRC screening effectiveness.

Risk of Malignancy in Adenomas Detected During Screening Colonoscopy

BACKGROUND & AIMS

A higher incidence of proximal interval cancers after colonoscopy has been reported in several follow-up studies. One possible explanation for this might be that proximally located adenomas have greater malignant potential. The aim of the present study was to assess the risk of malignancy in proximal versus distal adenomas in patients included in a large screening colonoscopy database; adenoma shape and the patients' age and sex distribution were also analyzed.

METHODS

Data for 2007-2012 from the German National Screening Colonoscopy Registry, including 594,614 adenomas identified during 2,532,298 screening colonoscopies, were analyzed retrospectively. The main outcome measure was the rate of high-grade dysplasia (HGD) in adenomas, used as a surrogate marker for the risk of malignancy. Odds ratios (ORs) for the rate of HGD found in adenomas were analyzed in relation to patient- and adenoma-related factors using multivariate analysis.

RESULTS

HGD histology was noted in 20,873 adenomas (3.5%). Proximal adenoma locations were not associated with a higher HGD rate. The most significant risk factor for HGD was adenoma size (OR 10.36 ≥1 cm vs <1 cm), followed by patient age (OR 1.26 and 1.46 for age groups 65-74 and 75-84 vs 55-64 years) and sex (OR 1.15 male vs female). In comparison with flat adenomas as a reference lesion, sessile lesions had a similar HGD rate (OR 1.02) and pedunculated adenomas had a higher rate (OR 1.23). All associations were statistically significant (P ≤ .05).

CONCLUSIONS

In this large screening database, it was found that the rates of adenomas with HGD are similar in the proximal and distal colon. The presence of HGD as a risk marker alone does not explain higher rates of proximal interval colorectal cancer. We suggest that certain lesions (flat, serrated lesions) may be missed in the proximal colon and may acquire a more aggressive biology over time. A combination of endoscopy-related factors and biology may therefore account for higher rates of proximal versus distal interval colorectal cancer.

Faecal immunochemical testing implementation to increase colorectal cancer screening in primary care

Colorectal cancer (CRC) is the second leading cause of cancer death in USA, and CRC screening remains suboptimal. The aim of this quality improvement was to increase CRC screening in the internal medicine clinic (IMC) patients, between the ages of 50–75 years, from a baseline rate of 50%–70% over 12 months with the introduction of faecal immunochemical test (FIT) testing. We used the Plan–Do–Study–Act (PDSA) method and performed a root cause analysis to identify barriers to acceptance of CRC screening. The quality improvement team created a driver diagram to identify and prioritise change ideas. We developed a process flow map to optimise opportunities to improve CRC screening. We performed eight PDSA cycles. The major components of interventions included: (1) leveraging health information technology; (2) optimising team work, (3) education to patient, physicians and IMC staff, (4) use of patient navigator for tracking FIT completion and (5) interactive workshops for the staff and physicians to learn motivational interview techniques. The outcome measure included CRC screening rates with either FIT or colonoscopy. The process measures included FIT order and completion rates. Data were analysed using a statistical process control and run charts. Four hundred and seven patients visiting the IMC were offered FIT, and 252 (62%) completed the test. Twenty-two (8.7%) of patients were FIT positive, 14 of those (63.6%) underwent a subsequent diagnostic colonoscopy. We achieved 75% CRC screening with FIT or colonoscopy within 12 months and exceeded our goal. Successful strategies included engaging the leadership, the front-line staff and a highly effective multidisciplinary team. For average-risk patients, FIT was the preferred method of screening. We were able to sustain a CRC screening rate of 75% during the 6-month postproject period. Sustainable annual FIT is required for successful CRC screening.

Population-based colorectal cancer screening: Interval cancers and relationship with the quantitative faecal immunological for hemoglobin

INTRODUCTION AND OBJECTIVE

The sensitivity of colorectal cancer screening programmes determines their effectiveness and is directly related to the interval cancer (IC). This study describes the frequency and characteristics of the IC of the Programme of Barcelona, Spain, and analyses its relationship with the quantitative value of the screening test (FIT).

MATERIAL AND METHODS

ICs after negative FIT of the first two rounds of the Programme (2010-2013) were included, observation period until July 2017. The information source of the ICs was their notification by professionals and patients, hospital databases and CMBD (Spanish Minimum Basic Data Set).

RESULTS

The sensitivity of the Programme is 82%. ICs are diagnosed more in proximal and rectal colon and in advanced stages than screening cancers, and have higher FIT values than overall people with negative FIT.

CONCLUSIONS

The sensitivity is acceptable and comparable to that of other programmes. The quantitative value of FIT in people with negative test should be included in the personalisation strategies of screening to reduce the risk of IC.

Interval cancers after negative immunochemical test compared to screen and non-responders' detected cancers in Slovenian colorectal cancer screening programme

Background

We assessed the incidence and characteristics of interval cancers after faecal immunochemical occult blood test and calculated the test sensitivity in Slovenian colorectal cancer screening programme.

Patients and methods

The analysis included the population aged between 50 to 69 years, which was invited for screening between April 2011 and December 2012. The persons were followed-up until the next foreseen invitation, in average for 2 years. The data on interval cancers and cancers in non-responders were obtained from cancer registry. Gender, age, years of schooling, the cancer site and stage were compared among three observed groups. We used the proportional incidence method to calculate the screening test sensitivity.

Results

Among 502,488 persons invited for screening, 493 cancers were detected after positive screening test, 79 interval cancers after negative faecal immunochemical test and 395 in non-responders. The proportion of interval cancers was 13.8%. Among the three observed groups cancers were more frequent in men (p = 0.009) and in persons aged 60+ years (p < 0.001). Comparing screen detected and cancers in non-responders with interval cancers more interval cancers were detected in persons with 10 years of schooling or more (p = 0.029 and p = 0.001), in stage III (p = 0.027) and IV (p < 0.001), and in right hemicolon (p < 0.001). Interval cancers were more frequently in stage I than non-responders cancers (p = 0.004). Test sensitivity of faecal immunochemical test was 88.45%.

Conclusions

Interval cancers in Slovenian screening programme were detected in expected proportions as in similar programmes. Test sensitivity was among the highest when compared to similar programmes and was accomplished using test kit for two stool samples.

Effectiveness of Colorectal Cancer Screening in Detecting Earlier-Stage Disease-A Nationwide Cohort Study in Denmark

BACKGROUND & AIMS

Most studies of the effectiveness of screening for colorectal cancer (CRC) using the fecal occult blood test tested the guaiac fecal occult blood test. However, the fecal immunochemical test (FIT) is now commonly used in screening. We aimed to evaluate the effectiveness of FIT-based screening for CRC on the number of incident CRC diagnoses and stage at diagnosis for individuals in Denmark who were invited for screening vs not yet invited.

METHODS

We collected data for this register-based retrospective cohort study during the first 16 months of the prevalence round of a FIT-based CRC screening program (March 1, 2014 through June 30, 2015). A total of 402,826 residents of Denmark (50-72 years old) were randomly invited to undergo CRC screening within the study period, and 956,514 were invited thereafter. We obtained information on CRC diagnosis, date, and stage at diagnosis from the Danish Colorectal Cancer Group database. Cancer incidence per 100,000 invited/not yet invited individuals was calculated, along with the relative risk (RR) of CRC among invited compared with not yet invited individuals.

RESULTS

CRC incidence during the study period was 339.4/100,000 invited individuals and 169.6/100,000 not yet invited individuals. CRC incidence increased with age among invited and not yet invited individuals. For invited women compared with not yet invited women, the RR of being diagnosed with stage I CRC was 3.39 (95% CI, 2.61-4.39), with stage II CRC was 2.16 (95% CI, 1.71-2.72), with stage III CRC was 1.37 (95% CI, 1.08-1.75), and with stage IV CRC was 0.92 (95% CI, 0.68-1.23). For invited men compared with not yet invited men, the RR of being diagnosed with stage I CRC was 3.71 (95% CI, 2.97-4.64); with stage II CRC was 2.26 (95% CI, 1.84-2.77), with stage III CRC was 1.88 (95% CI, 1.53-2.30), and with stage IV CRC was 1.20 (95% CI, 0.95-1.52).

CONCLUSIONS

In analyzing data from a register-based cohort study in Denmark, we found that inviting individuals to undergo FIT-based CRC screening led to detection of almost 2-fold more cases of CRC than not inviting participants. The significant increase of CRC incidence among those invited for screening indicates a need for awareness of treatment capacity in countries introducing FIT-based CRC screening.