Preferences and Acceptance of Colorectal Cancer Screening in Thailand

Colorectal cancer (CRC) is now common in Thailand with an increase in incidence over time. Health authoritiesare planning to implement a nationwide CRC screening program using fecal immunochemical test (FIT) as aprimary screening tool. This study aimed to estimate preferences and acceptance of FIT and colonoscopy, explorefactors influencing the acceptance, and investigate reasons behind choosing and rejecting to screen before theprogram was implemented. Patients aged 50-69, visiting the primary care unit during the study period, wereinvited to join this study. Patients with a history of cancer or past CRC screening were excluded. Face-to-faceinterviews were conducted. Subjects were informed about CRC and the screening tests: FIT and colonoscopy.Then, they were asked for their opinions regarding the screening. The total number of subjects was 437 (86.7%response rate). Fifty-eight percent were females. The median age was 58 years. FIT was accepted by 74.1% ofsubjects compared to 55.6% for colonoscopy. The acceptance of colonoscopy was associated with perceivedsusceptibility to CRC and family history of cancer. No symptoms, unwilling to screen, healthy, too busy and anxiousabout diagnosis were reasons for refusing to screen. FIT was preferred for its simplicity and non-invasivenesscompared with colonoscopy. Those rejecting FIT expressed a strong preference for colonoscopy. Subjects chosecolonoscopy because of its accuracy; it was refused for the process and complications. If the screening programis implemented for the entire target population in Thailand, we estimate that 106,546 will have a positive FIT,between 8,618 and 12,749 identified with advanced adenoma and between 2,645 and 3,912 identified with CRCin the first round of the program.     

Strong subsite‐specific variation in detecting advanced adenomas by fecal immunochemical testing for hemoglobin

Fecal immunochemical tests (FITs) for hemoglobin are increasingly recommended and used in colorectal cancer (CRC) screening. We aimed to provide a detailed assessment of the sensitivity of FIT according to type and subsite of neoplasms in a true screening setting. A quantitative FIT (FOB Gold, Sentinel Diagnostics, Milano, Italy) was applied prior to colonoscopy by 3,466 participants of the German screening colonoscopy program. Subsite specific sensitivity for various types of colorectal neoplasms was derived by comparing FIT results with findings at screening colonoscopy. The most advanced finding at colonoscopy was CRC, advanced adenoma, and nonadvanced adenoma in 29, 354 and 686 cases, respectively. Per‐adenoma sensitivity for large advanced adenomas (>1 cm) strongly varied by location (p < 0.001): cecum: 0/14 (0%), ascending colon and right flexure: 11/43 (26%), transverse colon and left flexure: 2/14 (14%), descending colon: 7/12 (58%), sigmoid colon: 47/92 (51%), rectum: 14/39 (36%). By contrast, the FIT detected all of 5 proximal CRC and 23 out of 24 (96%) distal CRCs, whereas per‐adenoma sensitivity of both proximal (17/259, 7%) and distal nonadvanced adenomas (20/237, 8%) essentially equaled the false positivity rate among those without neoplasms (152/2,397, 6%). In conclusion, we found a very large gradient of subsite specific FIT sensitivity for detecting large advanced adenomas ranging from 0% for advanced adenomas located in the cecum to >50% for those located in the descending or sigmoid colon. By contrast, FIT sensitivity was uniformly excellent for CRC and uniformly poor for nonadvanced adenomas, regardless of their location.     

Making colonoscopy-based screening more efficient: A “gateopener” approach

Screening colonoscopy for early detection and prevention of colorectal cancer (CRC) is mostly used inefficiently. Here, we assessed the potential of an innovative approach to colonoscopy-based screening, by use of a single, low threshold fecal immunochemical test (FIT) as a “gateopener” for screening colonoscopy. Using COSIMO, a validated simulation model, we modeled scenarios including either direct invitation to screening colonoscopy or an alternative approach involving mailing a single (“gateopener”) FIT along with an invitation to colonoscopy contingent on a FIT value above a low threshold yielding a 50% positivity rate (ie, every other pretest will be positive). Under plausible assumptions on screening offer adherence, we found that such “gateopener screening” (use of screening colonoscopy contingent on a positive, low threshold gateopener FIT) approximately doubled cancer detection rates vs conventional screening. In those spared from screening colonoscopy due to a negative gateopener FIT pretest, numbers needed to screen were 10-times higher vs those for individuals with a positive FIT, peaking in >2000 and >3800 (hypothetically) needed colonoscopies to detect one case of cancer in men and women, respectively. Gateopener screening resulted in 42%-51% and 59%-65% more prevented CRC cases and deaths, respectively. In summary, by directing colonoscopy capacities to those most likely to benefit, offering screening colonoscopy contingent on a “gateopener” low-threshold FIT would substantially enhance efficiency of colonoscopy screening.     

The Optimal Cut-Off Level of The Fecal Immunochemical Test For Colorectal Cancer Screening in a Country with Limited Colonoscopy Resources: A Multi-Center Study from Thailand

Background: Selecting the cut-off point for the fecal immunochemical test (FIT) for colorectal cancer (CRC) screening programs is of prime importance. The balance between the test performance for detecting advanced neoplasia and the available colonoscopy resources should be considered. We aimed to identify the optimal cut-off of FIT for advanced neoplasia in order to minimize colonoscopy burden. Methods: We conducted a multi-center study in 6 hospitals from diverse regions of Thailand. Asymptomatic participants, aged 50-75 years, were tested with one-time quantitative FIT (OC-SENSOR, Eiken Chemical Co.,Ltd., Tokyo, Japan) and all participants underwent colonoscopy. We assessed test performance in detecting advanced neoplasia (advanced adenoma and CRC) and measured the burden of colonoscopy with different cut-offs [25 (FIT25), 50 (FIT50), 100 (FIT100), 150 (FIT150), and 200 (FIT200)ng/ml]. Results: Among 1,479 participants, advanced neoplasia and CRC were found in 137 (9.3%) and 14 (0.9%), respectively. From FIT25 to FIT200, the positivity rate decreased from 18% to 4.9%. For advanced neoplasia, an increased cut-off decreased sensitivity from 42.3% to 16.8% but increased specificity from 84.2% to 96.3%. The increased cut-off increased the positive predictive value (PPV) from 21.5% to 31.5%. However, all cut-off points provided a high negative predictive value (NPV) (>90%). For CRC, the miss rate for FIT25 to FIT 150 was the same (n=3, 21%), whereas that with FIT200 increased to 35% (n=5). Conclusions: In a country with limited-colonoscopy resources, using FIT150 may be preferred because it offers both high PPV and NPV for advanced neoplasia detection. It could also decrease colonoscopy workload, while maintaining a CRC miss rate similar to those with lower cut-offs.     

Colorectal Cancer Screening among Government Servants in Brunei Darussalam

Background: This study concerns uptake and results of colorectal cancer (CRC) screening of governmentservant as part of the Health Screening Program that was conducted in Brunei Darussalam in 2009. Materialsand Methods: Government servants above the age of 40 or with family history of CRC were screened with a singlefecal occult blood test (FIT, immunohistochemistry). Among 11,576 eligible subjects, 7,360 (66.9%) returned theirspecimen. Subjects with positive family history of CRC (n=329) or polyps (n=135) were advised to attend clinicsto arrange screening. All the subjects with positive FIT (n=142, 1.9%) were referred to the endoscopy unit forcounselling for screening colonoscopy. Results: Overall only 17.7% of eligible subjects attended for screening;54.9% (n=79/142) of positive FIT, 8.8% (n=29/329) of positive family history of CRC and none with history ofpolyps (n=0/135). Of these, only 54 patients (50.5%) agreed for colonoscopy, 52 (48.6%) declined as they wereasymptomatic, and one was not offered (0.9%) due to his very young age. On screening colonoscopy, 12.9% (n=7)had advanced lesions including a sigmoid carcinoma in situ and six advanced polyps. The other findings includednon advanced polyps (n=21), diverticular (n=11) and hemorrhoids (n=26). One patient who missed his screeningcolonoscopy appointment re-presented two years later and was diagnosed with advanced right sided CRC. Allthe advanced lesions were detected in patients with positive FIT, giving a yield of 20.5% for advanced lesionsincluding cancers in the 5.1% FIT positive subjects. Conclusions: Our study showed screening for CRC evenwith a single FIT was effective. However, the uptake rate was poor with just over half of the patients agreeing toscreening colonoscopy. Measures to increase public awareness are important. Since one limitation of our studywas the relatively small sample size, larger studies should be conduced in future.     

Impact of adenoma detection on the benefit of faecal testing vs. colonoscopy for colorectal cancer

Colonoscopy quality, as measured by adenoma detection rates, varies widely across providers and is inversely related to patients' post‐colonoscopy cancer risk. This has unknown consequences for the benefits of faecal immunochemical testing (FIT) vs. primary colonoscopy screening for colorectal cancer. Using an established microsimulation model, we predicted the lifetime colorectal cancer incidence and mortality benefits of annual FIT vs. 10‐yearly colonoscopy screening at differing ADR levels (quintiles; averages 15.3–38.7%), with colonoscopy performance assumptions estimated from community‐based data on physician ADRs and patients' post‐colonoscopy risk of cancer. For patients receiving FIT screening with follow‐up colonoscopy by physicians from the highest ADR quintile, simulated lifetime cancer incidence and mortality were 28.8 and 5.4 per 1,000, respectively, vs. 20.6 and 4.4 for primary colonoscopy screening (risk ratios, RR = 1.40; 95% probability interval (PI), 1.19–1.71 for incidence, and RR = 1.22; 95%PI, 1.02–1.54 for mortality). With every 5% point ADR decrease, lifetime cancer incidence was predicted to increase on average 9.0% for FIT vs. 12.3% for colonoscopy, and mortality increased 9.9% vs. 13.3%. In ADR quintile 1, simulated mortality was lower for FIT than colonoscopy screening (10.1 vs. 11.8; RR = 0.85; 95%PI, 0.83–0.90), while incidences were more similar. This suggests that relative cancer incidence and mortality reductions for FIT vs. colonoscopy screening may differ by ADR, with fewer predicted deaths with colonoscopy screening in higher ADR settings and fewer deaths with annual FIT screening in lower ADR settings.     

Optimizing Screening for Colorectal Cancer: An Algorithm Combining Fecal Immunochemical Test,Blood-Based Cancer-Associated Proteins and Demographics to Reduce Colonoscopy Burden

BackgroundFecal Immunochemical Test (FIT) is widely used in population-based screening for colorectal cancer (CRC). This had led to major challenges regarding colonoscopy capacity. Methods to maintain high sensitivity without compromising the colonoscopy capacity are needed. This study investigates an algorithm that combines FIT result, blood-based biomarkers associated with CRC, and individual demographics, to triage subjects sent for colonoscopy among a FIT positive (FIT⁺) screening population and thereby reduce the colonoscopy burden.Materials and methodsFrom the Danish National Colorectal Cancer Screening Program, 4048 FIT⁺ (≥100 ng/mL Hemoglobin) subjects were included and analyzed for a panel of 9 cancer-associated biomarkers using the ARCHITECT i2000. Two algorithms were developed: 1) a predefined algorithm based on clinically available biomarkers: FIT, age, CEA, hsCRP and Ferritin; and 2) an exploratory algorithm adding additional biomarkers: TIMP-1, Pepsinogen-2, HE4, CyFra21-1, Galectin-3, B2M and sex to the predefined algorithm. The diagnostic performances for discriminating subjects with or without CRC in the 2 models were benchmarked against the FIT alone using logistic regression modeling.ResultsThe discrimination of CRC showed an area under the curve (AUC) of 73.7 (70.5-76.9) for the predefined model, 75.3 (72.1-78.4) for the exploratory model, and 68.9 (65.5-72.2) for FIT alone. Both models performed significantly better (P < .001) than the FIT model. The models were benchmarked vs. FIT at cutoffs of 100, 200, 300, 400, and 500 ng/mL Hemoglobin using corresponding numbers of true positives and false positives. All performance metrics were improved at all cutoffs.ConclusionA screening algorithm including a combination of FIT result, blood-based biomarkers and demographics outperforms FIT in discriminating subjects with or without CRC in a screening population with FIT results above 100 ng/mL Hemoglobin.     

Fecal immunochemical test accuracy in familial risk colorectal cancer screening

There is little information on fecal immunochemical test (FIT) in familial risk colorectal cancer (CRC) screening. Our study assesses FIT accuracy, number needed to scope (NNS) and cost to detect a CRC and an advanced neoplasia (AN) in this setting. We performed a multicentric, prospective, double‐blind study of diagnostic tests on individuals with first‐degree relatives (FDRs) with CRC submitted to screening colonoscopy. Two stool samples were collected and fecal hemoglobin in the first sample (FIT1) and the highest in both samples (FITmax) were determined. Areas under the curve (AUC) for CRC and AN as well as the best FIT1 and FITmax cutoff value for CRC were determined. At this threshold, NNS and the cost per lesion detected were calculated. A total of 595 individuals were included (one FDR > 60 years, 413; two FDR or one ≤ 60 years, 182). AN and CRC were found in 64 (10.8%) and six (1%) patients, respectively. For CRC diagnosis, FIT1 AUC was 0.96 [95% confidence interval (CI): 0.95–0.98] and FITmax AUC was 0.95 (95% CI: 0.93–0.97). For AN diagnosis, FIT1 and FITmax AUC were 0.74 (95% CI: 0.66–0.82). The best cutoff point for CRC was 115. At this threshold, the NNS to detect a CRC was 5.67 and 7.67, and the cost per CRC was 1,064€ and 1591.33€ on FIT1 and FITmax strategies, respectively. FIT shows high accuracy to detect CRC in familial CRC screening. Performing two tests does not improve diagnostic accuracy, but increases cost and NNS to detect a lesion.     

Changes in the choice of colorectal cancer screening tests in primary care settings from 7,845 prospectively collected surveys

Purpose

Colorectal cancer (CRC) is one of the leading causes of cancer mortality worldwide. This study examined factors influencing the choice of participants between colonoscopy and fecal immunochemical test (FIT) in a screening program and the impact of an unbiased educational session on influencing this decision.

Methods

Data from 7,845 participants who underwent screening between May 2008 and April 2011 was analyzed. Binary logistic regression and multinomial regression were performed to calculate the odds of selection of colonoscopy instead of FIT and the impact of the educational session on final participant choice, respectively.

Results

Of the 7,845 participants, 4,796 (61?%) underwent FIT and 3,049 (39?%) underwent colonoscopy. A significant number of participants changed their initial choice after the educational session, with 27.1?% changing to FIT from colonoscopy and 8?% changing from FIT to colonoscopy. Age, educational level, occupation, income, family history of CRC, perception of risk of CRC, and perceptions regarding CRC screening were significantly different among the groups choosing FIT and colonoscopy. Family history of CRC and high self-perception of CRC risk resulted in higher odds of choosing colonoscopy, whereas older age, single marital status, and negative perception of CRC screening resulted in lower odds. Perceptions of overall health status, occupation, low income, younger age, and negative perceptions of CRC screening were associated with higher odds of change in screening choice.

Conclusions

Those at higher odds of changing CRC screening options should be supported with more detailed explanations by primary care physicians to secure a more informed and considered choice.     

Willingness to Pay for Colorectal Cancer Screening and Effect of Copayment in Southern Thailand

Background: The incidence rate of colorectal cancer in Thailand is increasing. Hence, the nationwide screeningprogramme with copayment is being considered. There are two proposed screening alternatives: annual fecalimmunochemical test (FIT) and once-in-10-year colonoscopy. A copayment for FIT is 60 Thai baht (THB) per test(≈ 1.7 USD); a copayment for colonoscopy is 2,300 THB per test (≈ 65.5 USD). Methods: The willingness to pay(WTP) technique, which is theoretically founded on a cost-benefit analysis, was used to assess an effect of copayment onthe uptake. Subjects were patients aged 50-69 years without cancer or screening experience. WTP for the proposedtests was elicited. Results: Nearly two thirds of subjects were willing to pay for FIT. Less than half of subjects werewilling to pay for colonoscopy. Among them, median WTP for both tests was greater than the proposed copayments.In a probit model, knowing CRC patient and presence of companion were associated with non-zero WTP for FIT.Presence of companion, female, and family history of cancer were associated with non-zero WTP for colonoscopy.After adjustment for starting price in the linear model, marital status, drinking behavior, and risk attitude were associatedwith WTP. None of factors was significant for colonoscopy. Uptake decreased as levels of copayment increased.At proposed copayments, the uptake rates of 59.8% and 21.6% were estimated for colonoscopy and FIT respectively.The demand for FIT was price inelastic; the demand for colonoscopy was price elastic. Estimates of optimal copaymentwere 62.1 THB for FIT and 460.2 THB for colonoscopy. At the optimal copayment, uptake rates would be 59.8%for FIT and 42.3% for colonoscopy.Conclusion(s): More subjects were willing to pay for FIT than for colonoscopy(59.0% versus 46.5%). The estimated uptake rates were 59.8% and 21.6% for colonoscopy and FIT at the proposedcopayments.     

2015—2019年广州市结直肠癌筛查不同初筛方式阳性人群肠镜结果分析

[目的]分析2015—2019年广东省广州市结直肠癌筛查的数据,比较不同初筛方式阳性人群肠镜结果,以期更好地动员居民参与肠镜检查。[方法]整理2015—2019年广州市结直肠癌筛查数据,将初筛阳性人群分为5组:仅高危因素问卷评估阳性(免疫化学法粪便隐血试验阴性)[high risk factor questionnaire (HRFQ) positive and fecal immunochemical test(FIT)negative,HRFQ+&Double-FIT-]、HRFQ阳性和1次FIT阳性(HRFQ+&Single-FIT+)、HRFQ阴性和1次FIT阳性(HRFQ-&Single-FIT+)、HRFQ阴性和2次FIT阳性(HRFQ-&DoubleFIT+)、HRFQ阳性和2次FIT阳性(HRFQ+&Double-FIT+)。采用多元Logistic回归比较不同初筛方式阳性人群肠镜结果。[结果]广州市共完成初筛403 585人,初筛阳性69 619人,初筛阳性率为17.25%,肠镜检查依从性为28.53%;HRFQ+&Double-FIT+、HRFQ-&DoubleFIT+、HRFQ-&Single-FIT+、HRFQ+&Single-FIT+组检出异常风险分别是HRFQ+&DoubleFIT-组的1.638、1.642、1.174和1.515倍,HRFQ-&Double-FIT+和HRFQ+&Single-FIT+组检出腺瘤风险分别是HRFQ+&Double-FIT-组的1.306和1.214倍,HRFQ+&Double-FIT+、HRFQ-&Double-FIT+、HRFQ-&Single-FIT+、HRFQ+&Single-FIT+检出进展性腺瘤风险分别是HRFQ+&Double-FIT-组的4.823、5.870、2.571和2.463倍,HRFQ+&Double-FIT+、HRFQ-&Double-FIT+、HRFQ-&Single-FIT+、HRFQ+&Single-FIT+检出肠癌风险分别是HRFQ+&Double-FIT-组的33.532、31.345、5.353和6.627倍。[结论]广州市结直肠癌筛查肠镜检查依从性较低,应加大对结直肠癌初筛阳性人群的动员,尤其是FIT 2次阳性的人群。     

Uptake of faecal immunochemical test screening among nonparticipants in a flexible sigmoidoscopy screening programme

Screening programmes based on single modality testing may prevent individuals with a preference for a different test from participating. We conducted a population-based trial to determine whether nonparticipants in flexible sigmoidoscopy (FS) screening were willing to attend faecal immunochemical test (FIT) screening. In total, 8,407 subjects were invited in a primary FS screening programme. Invitees did not know at the time of FS invitation that nonparticipants would be offered FIT screening. A total of 4,407 nonparticipants of FS screening were invited for FIT screening (cut-off 50 ng haemoglobin/ml). The participation rate to FS screening was 31% [95% confidence interval (CI): 30-32%]. Among the FS nonparticipants 25% (CI: 24-26%) did attended FIT screening. The participation rate of the two-stage recruitment for FS and FIT screening was 45% (CI: 44-46%). FIT screenees were older (p = 0.02), more often women (p < 0.001) and had a lower social economic status (p = 0.01) than FS screenees. The detection rate (DR) for advanced adenoma was 3.5% (CI: 2.5-4.8%), and for colorectal cancer (CRC) it was 0.3% (CI: 0.1-0.8%) among participants to FIT screening. The DR of the two-stage recruitment was 6.1% (n = 202) for an advanced adenoma and 0.5% (n = 16) for a CRC. In conclusion, offering FIT screening to nonparticipants in a FS screening programme increases the overall participation rate considerably, as a quarter of nonparticipants of FS screening was willing to attend FIT screening. The participation rate remains lower for primary FIT screening in the same population (62%). Women in the target population were more likely to refuse FS than FIT screening. Countries introducing FS screening should be aware of these preferences.     

Screening strategies for colorectal cancer among patients with nonalcoholic fatty liver disease and family history

Patients with nonalcoholic fatty liver disease (NAFLD) and family history of colorectal cancer (CRC) are at higher risks but how they should be screened remains uncertain. Hence, we evaluated the cost‐effectiveness of CRC screening among patients with NAFLD and family history by different strategies. A hypothetical population of 100,000 subjects aged 40–75 years receive: (i) yearly fecal immunochemical test (FIT) at 50 years; (ii) flexible sigmoidoscopy (FS) every 5 years at 50 years; (iii) colonoscopy 10 yearly at 50 years; (iv) colonoscopy 10 yearly at 50 years among those with family history/NAFLD and yearly FIT at 50 years among those without; (v) colonoscopy 10 yearly at 40 years among those with family history/NAFLD and yearly FIT at 50 years among those without and (vi) colonoscopy 10 yearly at 40 years among those with family history/NAFLD and colonoscopy 10 yearly at 50 years among those without. The incremental cost‐effectiveness ratio (ICER) was studied by Markov modeling. It was found that colonoscopy, FS and FIT reduced incidence of CRC by 49.5, 26.3 and 23.6%, respectively. Using strategies 4, 5 and 6, the corresponding reduction in CRC incidence was 29.9, 30.9 and 69.3% for family history, and 33.2, 34.7 and 69.8% for NAFLD. Compared with no screening, strategies 4 (US$1,018/life‐year saved) and 5 (US$7,485) for family history offered the lowest ICER, whilst strategy 4 (US$5,877) for NAFLD was the most cost‐effective. These findings were robust when assessed with a wide range of deterministic sensitivity analyses around the base case. These indicated that screening patients with family history or NAFLD by colonoscopy at 50 years was economically favorable.     

Long‐term risk of colorectal cancer after negative colonoscopy in a Danish gFOBT screening cohort

Faecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all screen positive persons have negative colonoscopy, but consensus is lacking on how these persons should be followed up. Health authorities in Denmark and The Netherlands recommend suspending screening for 8–10 years, while patients in UK are invited to screening after 2 years. In this cohort‐study, we followed 166,277 individuals invited to FOBT‐screening in 2005–2006 and a reference group comprising the remaining 1,240,348 Danes of the same age. We linked Danish population and health service registers to obtain information about colonoscopy outcome and incident CRC. We estimated CRC risk by colonoscopy outcome (adenoma, other colorectal pathology or negative colonoscopy) for the reference group, the screening group, and subgroups. Persons with positive screening FOBT followed by negative colonoscopy had the same long‐term CRC risk as persons with adenoma detected due to a positive screening FOBT (aHR 1.33, 95% CI: 0.65–2.71). We found no difference in the long‐term CRC risk between persons with negative colonoscopy after a positive FOBT screening test and the unscreened reference population (aHR 1.05, 95% CI: 0.62–1.78). Since FOBT screen positive persons in our study remained at average risk of CRC despite of a negative index colonoscopy, we question the safety of suspending FOBT screening for this group. It needs to be monitored whether recent efforts to improve colonoscopy quality have been successful in ensuring low CRC risk after negative colonoscopy also in FOBT positive persons.     

Factors associated with false-positive fecal immunochemical tests in a large German colorectal cancer screening study

In recent years fecal immunochemical tests (FITs) have been offered as a primary screening test for colorectal cancer (CRC) in a growing number of countries. Our study aims to identify factors associated with apparently false-positive results of FITs. In this cross-sectional study within the German population-based screening colonoscopy program, participants were invited to provide a stool sample for FIT prior to colonoscopy. Four thousand six hundred and fifty six participants aged 50–79 years with no known history of CRC or inflammatory bowel disease (IBD) and no findings of neoplasms at screening colonoscopy were included in the current analyses. Main outcome measures were rates and factors associated with apparently false-positive FIT results. Apparently false-positive FIT results were found for 378 participants (8.1%). Male sex (OR = 1.30, 95%CI 1.03, 1.62), age ≥65 years (OR = 1.27, 95%CI 1.01, 1.59), a BMI ≥30 kg/m² (OR = 1.81, 95%CI 1.36, 2.40), current smoking (OR = 1.63, 95%CI 1.18, 2.25), use of aspirin (OR = 1.36, 95%CI 1.02, 1.82) and a new diagnosis of IBD (OR = 9.13, 95%CI 2.18, 38.19) or other non-neoplastic findings (OR = 1.86, 95%CI 1.37, 2.51) at screening colonoscopy were independently associated with significantly increased odds of a positive FIT. Although considered false positive in the context of CRC screening, the identified factors associated with apparently false-positive FIT results are known risk factors for and may point to conditions other than colorectal neoplasms that may be potential sources of gastrointestinal bleeding, potentially requiring further medical follow up.     

Current noninvasive tests for colorectal cancer screening: An overview of colorectal cancer screening tests

Colorectal cancer (CRC) has become the third most common cancer in the world. Screening has been shown to be an effective way to identify early CRC and precancerous lesions, and to reduce its morbidity and mortality. Several types of noninvasive tests have been developed for CRC screening, including the fecal occult blood test (FOBT), the fecal immunochemical test (FIT), the fecal-based DNA test and the blood-based DNA test (the SEPT9 assay). FIT has replaced FOBT and become the major screening test due to high sensitivity, specificity and low costs. The fecal DNA test exhibited higher sensitivity than FIT but its current cost is high for a screening assay. The SEPT9 assay showed good compliance while its performance in screening needs further improvements. These tests exhibited distinct sensitivity and specificity in screening for CRC and adenoma. This article will focus on the performance of the current noninvasive in vitro diagnostic tests that have been used for CRC screening. The merits and drawbacks for these screening methods will also be compared regarding the techniques, usage and costs. We hope this review can provide suggestions for both the public and clinicians in choosing the appropriate method for CRC screening.     

Participation and detection rates by age and sex for colonoscopy versus fecal immunochemical testing in colorectal cancer screening

Purpose

To compare two strategies for colorectal cancer screening: one-time colonoscopy versus fecal immunochemical testing (FIT) (and colonoscopy for positive) every 2 years, in order to determine which strategy provides the highest participation and detection rates in groups of sex and age.

Methods

This analysis was performed with data from the first screening round within the COLONPREV study, a population-based, multicenter, nationwide trial carried out in Spain. Several logistic regression models were applied to identify the influence of the screening test on participation rates and detection of proximal and distal neoplasms, as well to identify the influence of age and sex: women aged 50–59 years, women aged 60–69 years, men aged 50–59 years, and men aged 60–69 years.

Results

Participation was higher in women than in men, especially among women aged 50–59 years (25.91 % for colonoscopy and 35.81 % for FIT). Crossover from colonoscopy to FIT was higher among women than men, especially among those aged 60–69 years (30.37 %). In general, detection of any neoplasm and advanced adenoma was higher with colonoscopy than with FIT, but no significant differences were found between the two strategies for colorectal cancer detection. Detection of advanced adenoma in both arms was lower in women [specifically in women aged 50–59 years (OR 0.31; 95 % CI 0.25–0.38) than in men aged 60–69 years]. Women aged 50–59 years in the colonoscopy arm had a higher probability of detection of advanced adenoma (OR 4.49; 95 % CI 3.18–6.35), as well as of detection of neoplasms in proximal and distal locations (proximal OR 19.34; 95 % CI 12.07–31.00; distal OR 11.04; 95 % CI 8.13–15.01) than women of the same age in the FIT arm. These differences were also observed in the remaining groups but to a lesser extent.

Conclusion

Women were more likely to participate in a FIT-based strategy, especially those aged 50–59 years. The likelihood of detection of any neoplasm was higher in the colonoscopy arm for all the population groups studied, especially in women aged 50–59 years. Distinct population groups should be informed of the benefits of each screening strategy so that they may take informed decisions.     

Comparative yield and efficiency of strategies based on risk assessment and fecal immunochemical test in colorectal cancer screening: A cross-sectional population-based analysis

ObjectiveIntegration of risk stratification into fecal immunochemical test (FIT) might aid in the suboptimal detection of advanced neoplasms by FIT in colorectal cancer (CRC) screening. A comparative study was conducted to evaluate the participation and diagnostic yield of the parallel combination of questionnaire-based risk assessment (QRA) and FIT, FIT-only and QRA-only strategies in a CRC screening program in China.MethodsThe study included 29,626 individuals aged 40−74 years and invited to participate in a CRC screening program in China. Participants were first invited to undertake QRA and one-time FIT (OC-sensor). Participants with positive QRA or FIT were deemed to be high-risk individuals who were recommended for subsequent colonoscopy. Participation, detection rate, and resource demand for colonoscopy were calculated and compared.ResultsOf the 29,626 invitees, 20,203 completed the parallel combination, 8,592 completed the QRA-only, and 11 completed the FIT-only strategy. For the parallel combination, FIT-only, and QRA-only strategies, the overall positivity rates were 10.2% (2,928/28,806), 5.4% (1,096/20,214), and 6.8% (1,944/28,795), respectively; the yield of advanced neoplasm per 10,000 invitees were 46.9 [95% confidence interval (95% CI): 39.8−55.4], 36.8 (95% CI: 30.5−44.4), and 12.2 (95% CI: 8.8−16.8), respectively; the positive predictive values for detecting advanced neoplasms among participants who completed colonoscopy were 4.7% (95% CI: 4.0%−5.6%), 9.9% (95% CI: 8.3%−11.9%), and 1.9% (95% CI: 1.3%−2.6%), respectively; the number of colonoscopies required to detect one advanced neoplasm was 11.4 (95% CI: 9.8−13.4), 5.7 (95% CI: 4.8−6.7), and 28.4 (95% CI: 20.7−39.2), respectively.ConclusionsThe parallel combination of QRA and FIT did not show superior efficacy for detecting advanced neoplasm compared with FIT alone in this CRC screening program.     

Pioneering Annual Colorectal Cancer Screening and Treatment Targeting Low Income Communities in Malaysia (20102015)

The aim of this study was to assess the rate of uptake of a customised annual Colorectal Cancer Awareness, Screening and Treatment Project (CCASTP) using faecal immunohistochemical test (FIT) kits in low income communities in Malaysia. The immediate objectives were (1) to evaluate the level of adherence of CRC screening among lowincome groups, (2) to assess the knowledge and awareness of the screened population and (3) to assess the accuracy of FIT kits. A total of 1,581 FIT kits were distributed between years 2010 to 2015 to healthy asymptomatic participants of the annual CCASTP organized by Empowered the Cancer Advocacy Society of Malaysia. Data for sociodemographic characteristics, critical health and lifestyle information of the registered subjects were collected. Findings for use of the FIT kits were collected when they were returned for stool analyses. Those testingd positive were invited to undergo a colonoscopy examination. A total of 1,436 (90.8%) of the subjects retuned the FITkits, showing high compliance. Among the 129 subjects with positive FIT results, 92 (71.3%) underwent colonoscopy. Six cases (6.5%) of CRC were found. Based on the data collected, the level of awareness of stool examination and knowledge about CRC was poor amongst the participants. Gender, age group, ethnicity and risk factors (i.e. smoking, lack of exercise and low consumption of fresh fruits) were associated with positive FITkit results. In conclusion, CRC screening can be performed in the community with a single FITkit. Although CRC knowledge and awareness is poor in lowincome communities, the average return rate of the FIT kits and rate of colonoscopy examination were 91.2% and 70.3%, respectively.     

Changes in colorectal cancer screening use after introduction of alternative screening offer in Germany: Prospective cohort study

In October 2002, screening colonoscopy was added to the German colorectal cancer (CRC) screening program as an alternative to fecal occult blood test (FOBT). We aimed to evaluate the change in CRC screening use after introduction of the dual screening offer and to assess determinants of screening use. Data were drawn from a population-based cohort study initiated during 2000–2002 in Germany (n = 5,845, age range at recruitment: 50–75 years). We conducted both cross-sectional and longitudinal analyses to obtain uptake rates of CRC screening based on four waves of data. Age-group specific proportions of participants having had FOBT within 2 years remained essentially unchanged at 61–67% between 2000 and 2002 (1st wave) and 2005–2007 (3rd wave). The proportions of participants having undergone screening colonoscopy within 10 years increased from 23–29% to 46–57%, leading to a substantial overall increase in being up-to-date with CRC screening from 66–68% to 77–80%. In 2008–2010 (4th wave), FOBT use declined and colonoscopy use continued to increase. Obesity was significantly associated with lower prevalence of being up-to-date with FOBT (odds ratio [OR] at 8-year follow-up 0.68; 95% confidence interval [CI], 0.58–0.80) and screening colonoscopy (OR, 0.73; 95% CI, 0.62–0.86). Also, smokers were less likely to have ever used FOBT (OR, 0.54; 95% CI, 0.40–0.75) or colonoscopy (OR, 0.75; 95% CI, 0.63–0.90) compared to nonsmokers. After the introduction of dual screening offer, the overall adherence to CRC screening steeply increased, mainly due to an increase in screening colonoscopy uptake. Screening tests kept being underused by obese people and smokers who are at elevated CRC risk.