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.     

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.     

Clinical Features of Fecal Immunochemical Test-Negative Colorectal Lesions based on Colorectal Cancer Screening among Asymptomatic Participants in Their 50s

Objective: To improve the efficacy of colorectal cancer (CRC) screening, decreasing the occurrence of interval cancers is essential. Most interval CRCs develop from fecal immunochemical test (FIT)-negative CRC. This study examined the clinical characteristics of FIT-negative advanced neoplasms (AN) and sessile serrated lesions (SSL), which are main candidate precursors of FIT-negative CRC, and the eligibility criteria for total colonoscopy (TCS) screening following negative FIT. Methods: Asymptomatic participants in their 50s were divided into two groups. The FIT-negative group underwent TCS following negative FIT, and the TCS-only group underwent TCS without FIT. One endoscopist reviewed the endoscopic images. Plausible risk factors for colorectal polyps were extracted. The clinical features of AN and SSL were compared between the groups. Result: Of 2,437 participants, 56.2% were included in the FIT-negative group. No between-group differences were recorded for the prevalence of different colorectal polyp types. By multivariate analysis, a significantly lower adjusted odds ratio (AOR) of AN was shown in women, and significantly higher AORs of AN were found for aging, smoking, and a family history of CRC. The AOR of SSL was higher for smokers. The proportion of AN in the right colon was higher in the FIT-negative group. No between-group differences were recorded for SSL. Conclusion: FIT screening was less likely to detect CRC and certain precancerous lesions in the right colon. Combining annual FIT with TCS for the high-risk population based on a scoring system, may detect FIT-negative CRC and colorectal polyps, thus, reducing interval cancer.     

Test performance of immunologic fecal occult blood testing and sigmoidoscopy compared with primary colonoscopy screening for colorectal advanced adenomas

Given the current increase in colorectal cancer screening, information on performance of screening tests is needed, especially in groups with a presumed lower test performance. We compared test performance of immunologic fecal occult blood testing (FIT) and pseudosigmoidoscopy with colonoscopy for detection of advanced adenomas in an average risk screening population. In addition, we explored the influence of gender, age, and location on test performance. FIT was collected prior to colonoscopy with a 50 ng/mL cutoff point. FIT results and complete colonoscopy findings were available from 329 subjects (mean age: 54.6 ± 3.7 years, 58.4% women). Advanced adenomas were detected in 38 (11.6%) of 329 subjects. Sensitivity for advanced adenomas of FIT and sigmoidoscopy were 15.8% (95% CI: 6.0-31.3) and 73.7% (95% CI: 56.9-86.6), respectively. No sensitivity improvement was obtained using the combination of sigmoidoscopy and FIT. Mean fecal hemoglobin in FIT positives was significantly lower for participants with only proximal adenomas versus those with distal ones (P = 0.008), for women versus men (P = 0.023), and for younger (<55 years) versus older (≥55 years) subjects (P = 0.029). Sensitivities of FIT were 0.0% (95% CI: 0.0-30.9) in subjects with only proximal versus 21.4% (95% CI: 8.3-41.0) in those with distal nonadvanced adenomas; 5.3% (95% CI: 0.0-26.0) in women versus 26.3% (95% CI: 9.2-51.2) in men; 9.5% (95% CI: 1.2-30.4) in younger versus 23.5% (95% CI: 6.8-49.9) in older subjects. Sigmoidoscopy had a significantly higher sensitivity for advanced adenomas than FIT. A single FIT showed very low sensitivity, especially in subjects with only proximal nonadvanced adenomas, in women, and in younger subjects. This points to the existence of "low" FIT performance in subgroups and the need for more tailored screening strategies.     

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.     

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.     

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.     

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.     

Lack of Association between Red Meat Consumption and a Positive Fecal Immunochemical Colorectal Cancer Screening Test in Khon Kaen,Thailand: a Population- Based Randomized Controlled Trial

Background: There is convincing evidence from epidemiological studies that meat consumption increases colorectal cancer (CRC) risk. However, assessment of any association with a positive fecal immunochemical test (FIT) in CRC screening has been limited. If a link could be shown this might be helpful for establishing a risk group for colonoscopy. Objective: This study aimed to assess any association between meat consumption and other lifestyle factors and a positive FIT result in a Thai population. Methods: A cross-sectional analytical study was conducted with 1,167 participants in a population-based randomized controlled trial. CRC was screened from May 2016 - February 2017. Subjects aged 45-74 years who met the eligibility criteria were randomly allocated to the study arm. A positive FIT was determined with cut-off 100 ng/mL. Multiple logistic regression was used to analyze any relationship between lifestyle factors and a positive FIT. Result: The total number of subjects was 1,060 (90.8% return rate of FIT). With FIT100, FIT150, and FIT200, positive tests were found in 92 (8.68%), 74 (6.98%), and 60 (5.66%), respectively. No significant associations were noted with any of the variables, except for being aged 60-74 years (ORadj = 1.62, 95% CI: 1.03-2.54) Borderline significance was observed for high consumption of vegetables (ORadj = 0.62, 95% CI: 0.36-1.07) and being male (ORadj = 1.39, 95% CI: 0.87-2.22). Conclusion: Despite the evidence from the literature, no association was here found between a positive FIT result and meat consumption or other well-established lifestyle parameters. Being aged 60-74 years was a risk factor which should be taken into account in CRC screening strategy in countries like Thailand with limited access to endoscopy.     

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.     

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.     

The impact of stratifying by family history in colorectal cancer screening programs

In the province‐wide colorectal cancer (CRC) screening program in Ontario, Canada, individuals with a family history of CRC are offered colonoscopy screening and those without are offered guaiac fecal occult blood testing (gFOBT, Hemoccult II). We used microsimulation modeling to estimate the cumulative number of CRC deaths prevented and colonoscopies performed between 2008 and 2038 with this family history‐based screening program, compared to a regular gFOBT program. In both programs, we assumed screening uptake increased from 30% (participation level in 2008 before the program was launched) to 60%. We assumed that 11% of the population had a family history, defined as having at least one first‐degree relative diagnosed with CRC. The programs offered screening between age 50 and 74 years, every two years for gFOBT, and every ten years for colonoscopy. Compared to opportunistic screening (2008 participation level kept constant at 30%), the gFOBT program cumulatively prevented 6,700 more CRC deaths and required 570,000 additional colonoscopies by 2038. The family history‐based screening program increased these numbers to 9,300 and 1,100,000, a 40% and 93% increase, respectively. If biennial gFOBT was replaced with biennial fecal immunochemical test (FIT), annual Hemoccult Sensa or five‐yearly sigmoidoscopy screening, both the added benefits and colonoscopies required would decrease. A biennial gFOBT screening program that identifies individuals with a family history of CRC and recommends them to undergo colonoscopy screening would prevent 40% (range in sensitivity analyses: 20–51%) additional deaths while requiring 93% (range: 43–116%) additional colonoscopies, compared to a regular gFOBT 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.     

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.     

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.     

Risk factors for advanced sporadic colorectal neoplasia in persons younger than age 50

Background: Colorectal cancer (CRC) screening is recommended for average-risk adults beginning at age 50. However, 7% of CRC occurs in persons younger than age 50, a group for which risk factors are not well defined. We sought to determine whether a retrospective case-control study could identify risk factors for sporadic CRC and advanced adenomatous polyps (together known as sporadic colorectal neoplasia [CRN]). Methods: Using the cancer registry, medical records, and endoscopy and pathology reports from six local hospitals, we identified potentially eligible persons with CRN (cases) or controls who had no neoplasia on colonoscopy between January 1, 2000 and December 31, 2002. Consenting subjects completed a survey encompassing medical and family history, physical measures, lifestyle habits, and diet. Results: Surveys were completed by 20 (15%) of 130 potentially eligible cases and by 54 (13%) of 408 potentially eligible controls. The following factors differed between cases and controls: living with a spouse/significant other (55% vs. 80%; P = 0.034); prior pelvic irradiation (20% vs. 2%; P = 0.019); having a first-degree relative with CRC (25% vs. 7%; P = 0.05); having had a prior sigmoidoscopy, colonoscopy, or barium enema (15% vs. 41%; P = 0.038); and lightest weight since age 21 (155 lbs vs. 135 lbs; gender-adjusted P = 0.049). Conclusions: The low recruitment rate of this retrospective case-control study precludes its use for a larger, more definitive study. Several potential risk factors for advanced sporadic CRN were identified. It remains to be determined whether these factors represent an artifact of selection bias or true risk factors that may be used to stratify risk and target screening in persons under age 50.     

Screening colonoscopy participation in Turkish colorectal cancer patients and their first degree relatives

Background: This study aimed to research the awareness of screening colonoscopy (SC) among patientswith colorectal cancer (CRC) and their relatives. Methodology: A questionnaire form including information andbehavior about colonoscopic screening for CRCs of patients and their first-degree relatives (FDRs) was prepared.Results: A total of 406 CRC patients were enrolled into the study, with 1534 FDRs (siblings n: 1381 and parentsn: 153) . Positive family history for CRC was found in 12% of the study population. Previous SC was performedin 11% of patients with CRC. Mean age of the patients whose FDRs underwent SC was lower than the patientswhose FDRs did not (52 vs 57 years; p<0,001). The frequency of SC in FDRs was 64% in patients diagnosedCRC under 35 years of age. Persons having a positive family history of CRC had SC more often (51 vs 22%,p<0,001). FDRs of patients having a higher educational level and income had SC more frequently. Conclusions:When screening for CRC is planned, elderly subjects, those with family history for CRC, and those with loweducational and lower income should be given esspecial attention in order that they be convinced to undergoscreening for CRC.     

定量粪便免疫化学试验筛查阈值对结直肠肿瘤早筛价值的影响

目的:分析定量粪便免疫化学试验（fecal immunochemistry test，FIT）筛查阈值对体检人群结直肠肿瘤早筛价值的影响。方法:以2017年07月至2021年06月在我院接受定量FIT检测并行肠镜检查的1 267例人群为研究对象，比较不同性质肿瘤的定量FIT数值和阳性率。通过Logistic 回归和受试者工作特征（receiver operating characteristic，ROC）曲线分析比较不同性别、年龄和不同阳性阈值下定量FIT对进展期肿瘤的筛检效能。结果:定量 FIT筛查阳性率为4.7%，阳性人群肠镜依从性为22.2%。结直肠癌患者的定量FIT数值高于进展期腺瘤和其他肠镜结果。当定量FIT水平为100~199 μg/L、200~299 μg/L、300~499 μg/L和500 μg/L以上时，患进展期肿瘤的风险分别是<100 μg/L时的4.296倍、4.121倍、6.506倍和10.474倍。不同阳性阈值下，FIT阳性组进展期肿瘤检出率均高于阴性组，且在男性和50~75岁人群中均有统计学差异。在100 μg/L时的比值比（odds ratio，OR）最大（总体OR=6.817，95%CI:2.727~17.040；男性OR=5.570，95%CI:2.198~14.115；50~75岁OR=10.178，95%CI:3.158~32.803）。此时，定量FIT对进展期肿瘤的灵敏度分别为94.7%、93.0%、96.2%，特异度分别为27.6%、29.6%、28.7%。当阳性阈值由100 μg/L升高至500 μg/L时，FIT诊断进展期肿瘤的灵敏度下降，特异度升高，但阳性预测值和阴性预测值变化不大。结论:定量FIT阳性阈值在100 μg/L时筛查进展期结直肠肿瘤的灵敏度较好，但特异度较低，是应用在体检人群伺机性筛查中较好的结直肠肿瘤早筛参考指标。     

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.     

Colonoscopy Screening Results in at Risk Iranian Population

Objectives: To investigate the prevalence of colorectal adenomas and other advanced lesions in first degreerelatives of Iranian patients diagnosed with colorectal cancer by colonoscopy and pathologic evaluation. Methods:Iranian colorectal cancer patients (probands) were identified through pathologic reports of the regional cancerregistry. First degree relatives (siblings, parents and offspring) of probands were evaluated for the existence ofpolyps and precancerous lesions via colonoscopy screening. Control patients were chosen among average riskpopulation with no family history of colorectal cancer who agreed to colonoscopy screening. Results: A total of184 subjects underwent colonoscopy screening from April 2007 to March 2009. From 90 cases among familiesof probands, 70 (77.8%) had a normal colonoscopy result, 18 (20%) demonstrated polyps and 2 (2.2%) werediagnosed with colorectal cancer. Colonoscopy screening in 94 average risk control patients discovered polypsin 4 (4.3%) cases and the other 90 (95.7%) patients had normal total colonoscopy results. Mean age of caseswith advanced lesions was 48.4±10.2 and 41.5±18.4 in control patients with polyps. The incidence of polyps wassignificantly higher in males, and in family case patients compared to controls. Conclusions: Based on colonoscopyscreening, the prevalence of colorectal adenoma and precancerous lesions in first degree relatives of patientsdiagnosed with colorectal cancer is significantly higher than in the average risk population.