Barrier-focused intervention to increase colonoscopy attendance among nonadherent high-risk populations

Effect of Behavioral Interventions on the Uptake of Colonoscopy for Colorectal Cancer Screening: A Systematic Review and Meta-Analysis

INTRODUCTION

Screening decreases colorectal cancer incidence and mortality, but uptake in the United States remains suboptimal. Prior studies have investigated the effect of various interventions on overall colorectal cancer screening and stool-based testing, but the effect on colonoscopy-the predominant screening test in the United States-has not been fully examined. We performed a systematic review and meta-analysis to assess the effect of behavioral interventions on screening colonoscopy uptake.

METHODS

We searched PubMed, Embase, and Cochrane databases through January 2022 for controlled trials that assessed the effect of behavioral interventions on screening colonoscopy uptake. All titles, abstracts, and articles were screened by at least 2 independent reviewers. Odds ratios were extracted from the original article or calculated from the raw data. The primary outcome was the relative increase in screening colonoscopy completion with any behavioral intervention. We performed random-effects meta-analysis, with subgroup analysis by type of intervention.

RESULTS

A total of 25 studies with 30 behavioral interventions were analyzed. The most common interventions were patient navigation (n = 11) and multicomponent interventions (n = 6). Overall, behavioral interventions increased colonoscopy completion by 54% compared with controls (odds ratio [OR] 1.54, 95% confidence interval [CI] 1.26-1.88). Patient navigation (OR 1.78, 95% CI 1.35-2.34) and multicomponent interventions (OR 1.84, 95% CI 1.17-2.89) had the strongest effect on colonoscopy completion among interventions examined in multiple studies. Significant heterogeneity was observed both overall and by intervention type. There was no evidence of publication bias.

DISCUSSION

Behavioral interventions increase screening colonoscopy completion and should be adopted in clinical practice. In particular, patient navigation and multicomponent interventions are the best-studied and most effective interventions.

Clinical evaluation of a multitarget fecal immunochemical test-sDNA test for colorectal cancer screening in a high-risk population: a prospective, multicenter clinical study

Colorectal cancer (CRC) is a major malignancy threatening the health of people in China and screening could be effective for preventing the occurrence and reducing the mortality of CRC. We conducted a multicenter, prospective clinical study which recruited 4,245 high-risk CRC individuals defined as having positive risk-adapted scores or fecal immunochemical test (FIT) results, to evaluate the clinical performance of the multitarget fecal immunochemical and stool DNA (FIT-sDNA) test for CRC screening. Each participant was asked to provide a stool sample prior to bowel preparation, and FIT-sDNA test and FIT were performed independently of colonoscopy. We found that 186 (4.4%) were confirmed to have CRC, and 375 (8.8%) had advanced precancerous neoplasia among the high CRC risk individuals. The sensitivity of detecting CRC for FIT-sDNA test was 91.9% (95% CI, 86.8-95.3), compared with 62.4% (95% CI, 54.9-69.3) for FIT (P < 0.001). The sensitivity for detecting advanced precancerous neoplasia was 63.5% (95% CI, 58.3-68.3) for FIT-sDNA test, compared with 30.9% (95% CI, 26.3-35.6) for FIT (P < 0.001). Multitarget FIT-sDNA test detected more colorectal advanced neoplasia than FIT. Overall, these findings indicated that in areas with limited colonoscopy resources, FIT-sDNA test could be a promising further risk triaging modality to select patients for colonoscopy in CRC screening.

Implementation research on noncommunicable disease prevention and control interventions in low- and middle-income countries: A systematic review

BACKGROUND

While the evidence for the clinical effectiveness of most noncommunicable disease (NCD) prevention and treatment interventions is well established, care delivery models and means of scaling these up in a variety of resource-constrained health systems are not. The objective of this review was to synthesize evidence on the current state of implementation research on priority NCD prevention and control interventions provided by health systems in low- and middle-income countries (LMICs).

METHODS AND FINDINGS

On January 20, 2021, we searched MEDLINE and EMBASE databases from 1990 through 2020 to identify implementation research studies that focused on the World Health Organization (WHO) priority NCD prevention and control interventions targeting cardiovascular disease, cancer, diabetes, and chronic respiratory disease and provided within health systems in LMICs. Any empirical and peer-reviewed studies that focused on these interventions and reported implementation outcomes were eligible for inclusion. Given the focus on this review and the heterogeneity in aims and methodologies of included studies, risk of bias assessment to understand how effect size may have been compromised by bias is not applicable. We instead commented on the distribution of research designs and discussed about stronger/weaker designs. We synthesized extracted data using descriptive statistics and following the review protocol registered in PROSPERO (CRD42021252969). Of 9,683 potential studies and 7,419 unique records screened for inclusion, 222 eligible studies evaluated 265 priority NCD prevention and control interventions implemented in 62 countries (6% in low-income countries and 90% in middle-income countries). The number of studies published has been increasing over time. Nearly 40% of all the studies were on cervical cancer. With regards to intervention type, screening accounted for 49%, treatment for 39%, while prevention for 12% (with 80% of the latter focusing on prevention of the NCD behavior risk factors). Feasibility (38%) was the most studied implementation outcome followed by adoption (23%); few studies addressed sustainability. The implementation strategies were not specified well enough. Most studies used quantitative methods (86%). The weakest study design, preexperimental, and the strongest study design, experimental, were respectively employed in 25% and 24% of included studies. Approximately 72% of studies reported funding, with international funding being the predominant source. The majority of studies were proof of concept or pilot (88%) and targeted the micro level of health system (79%). Less than 5% of studies report using implementation research framework.

CONCLUSIONS

Despite growth in implementation research on NCDs in LMICs, we found major gaps in the science. Future studies should prioritize implementation at scale, target higher levels health systems (meso and macro levels), and test sustainability of NCD programs. They should employ designs with stronger internal validity, be more conceptually driven, and use mixed methods to understand mechanisms. To maximize impact of the research under limited resources, adding implementation science outcomes to effectiveness research and regional collaborations are promising.

Robust performance of a novel stool DNA test of methylated SDC2 for colorectal cancer detection: a multicenter clinical study

BACKGROUND AND AIMS

Stool DNA testing is an emerging and attractive option for colorectal cancer (CRC) screening. We previously evaluated the feasibility of a stool DNA (sDNA) test of methylated SDC2 for CRC detection. The aim of this study was to assess its performance in a multicenter clinical trial setting.

METHODS

Each participant was required to undergo a sDNA test and a reference colonoscopy. The sDNA test consists of quantitative assessment of methylation status of SDC2 promoter. Results of real-time quantitative methylation-specific PCR were dichotomized as positive and negative, and the main evaluation indexes were sensitivity, specificity, and kappa value. All sDNA tests were performed and analyzed independently of colonoscopy.

RESULTS

Among the 1110 participants from three clinical sites analyzed, 359 and 38 were diagnosed, respectively, with CRC and advanced adenomas by colonoscopy. The sensitivity of the sDNA test was 301/359 (83.8%) for CRC, 16/38 (42.1%) for advanced adenomas, and 134/154 (87.0%) for early stage CRC (stage I-II). Detection rate did not vary significantly according to age, tumor location, differentiation, and TNM stage, except for gender. The follow-up testing of 40 postoperative patients with CRC returned negative results as their tumors had been surgically removed. The specificity of the sDNA test was 699/713 (98.0%), and unrelated cancers and diseases did not seem to interfere with the testing. The kappa value was 0.84, implying an excellent diagnostic consistency between the sDNA test and colonoscopy.

CONCLUSION

Noninvasive sDNA test using methylated SDC2 as the exclusive biomarker is a clinically viable and accurate CRC detection method.

CHINESE CLINICAL TRIAL REGISTRY

Chi-CTR-TRC-1900026409, retrospectively registered on October 8, 2019; http://www.chictr.org.cn/edit.aspx?pid=43888&htm=4 .

High-Yield Methylation Markers for Stool-Based Detection of Colorectal Cancer

BACKGROUND

Many methylation markers associated with colorectal cancer have been reported, but few of them are actually used in clinical practice.

AIMS

This study was designed to identify promising methylation markers for stool-based detection of colorectal cancer.

METHODS

We first tested 324 reported methylated genes in colorectal cancer cell lines. A total of 111 heavily methylated genes were selected for further evaluation with a pilot set of colorectal cancer and adjacent normal tissues. Ten high-yield methylated markers were further studied in 319 tissue samples. Eventually, the four best markers, namely methylated COL4A1, COL4A2, TLX2, and ITGA4, were validated in 240 stool samples. Methylation-specific PCR (MSP) and real-time MSP (qMSP) were employed for methylation detection.

RESULTS

After hierarchical selection, ten differentially methylated genes demonstrated high sensitivity and specificity for the detection of colorectal cancer in tissue. When validated in stool samples, the four with the best performance-COL4A1, COL4A2, TLX2, and ITGA4-were able to detect 82.5-92.5% of colorectal cancers and 41.6-58.4% of adenomas (≥ 1 cm) with specificity of 88.0-96.4%. The best combination, COL4A2 and TLX2, detected 91.3% of CRCs and 51.9% of advanced adenomas in stool with 97.6% specificity.

CONCLUSIONS

Methylated COL4A1, COL4A2, TLX2, and ITGA4 demonstrated high accuracy for the detection of colorectal neoplasms in stool. They are potentially valuable markers for the detection of colorectal cancer.

Invitation to Screening Colonoscopy in the Population at Familial Risk for Colorectal Cancer

BACKGROUND

Screening colonoscopy can lower the incidence of colorectal cancer (CRC), yet participation rates are low even in groups at high risk. The goal of this study was to double the rate of participation in screening colonoscopy among persons at familial risk and then to determine the frequency of neoplasia in this risk group.

METHODS

In a nationwide, cluster-randomized, multicenter study, first-degree relatives (FDR) of patients with CRC across Germany received written informational materials concerning the familial risk of CRC, along with an invitation to undergo colonoscopy. Participants in the intervention group were additionally counseled by nurses over the telephone. The primary endpoint of the study was colonoscopy uptake within 30 days.

RESULTS

The participants' mean age was 50.8 years. The colonoscopy uptake rates were 99/125 (79%) in the intervention group and 97/136 (71%) in the control group (RR = 1.11; 95% confidence interval [0.97; 1.28]). A polypectomy was performed in 72 of 196 asymptomatic persons (37%). In 13 cases (7%), an advanced neoplasia was detected; two of these persons had colon cancer (stages T0 and T1). 42% of the participants expressed barriers against colonoscopy. 22 reported mild side effects; there were no serious side effects.

CONCLUSION

Additional counseling by nurses over the telephone does not increase the participation rate. Approaching patients who have CRC is an opportunity to increase the participation of their first-degree relatives in screening colonoscopy. The frequency of neoplasia that was found in this study underscores the need to screen relatives even before they reach the usual age threshold for screening.

The role of mSEPT9 in screening, diagnosis, and recurrence monitoring of colorectal cancer

Background

The application of circulating, cell-free, methylated Septin9 (^mSEPT9) DNA in screening and recurrence monitoring is highly promising. CpG island methylator phenotype (CIMP) is associated with microsatellite instability (MSI). The present study was performed to determine the diagnostic accuracy of ^mSEPT9 for colorectal cancer (CRC) and to evaluate its utility in CRC screening and recurrence monitoring.

Methods

For screening and diagnosis of CRC, peripheral ^mSEPT9 detection and fecal occult blood test (FOBT) were performed in 650 subjects, then the level of CEA, CA19–9 and CA724 was quantified in 173 subjects. Clinicopathological parameters and mismatch repair protein were detected among subjects with CRC. For recurrence monitoring of CRC, the sensitivity of ^mSEPT9 of 70 subjects was compared with tumor markers and contrast enhanced computed tomography (CECT).

Results

Seventy-three percent of CRC patients were ^mSEPT9-positive at 94.5% specificity, and 17.1% of patients with intestinal polyps and adenoma were ^mSEPT9-positive at 94.5% specificity, which were higher than FOBT for the screening of CRC. The sensitivity and specificity of ^mSEPT9 for diagnosis and recurrence monitoring were higher than that of CEA, CA19–9 and CA724. The combined detection of ^mSEPT9 and CECT enhanced the sensitivity for recurrence monitoring. Pre-therapeutic levels of ^mSEPT9 were strongly associated with TNM stage, Dukes stages and mismatch repair deficiency (dMMR).

Conclusions

^mSEPT9 analysis might be popularized as a routine biomarker for CRC screening. The combined detection of ^mSEPT9 and CECT can play an important role for recurrence monitoring. CIMP was highly associated with the pathological stage of CRC and dMMR.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5663-8) contains supplementary material, which is available to authorized users.

Stool DNA Test of Methylated Syndecan-2 for the Early Detection of Colorectal Neoplasia

Background: Although the incidence of colorectal cancer is steadily increasing, screening for colorectal cancer with conventional approaches is not routinely performed in China. Noninvasive screening methods are attractive options to resolve this issue. Syndecan-2 (SDC2) is frequently methylated in colorectal cancer. However, the value of a stool test of methylated SDC2 for the detection of colorectal cancer is unknown.Methods: Methylation status of SDC2 was tested in cell lines and 398 colorectal tissue samples and further evaluated with 497 stool samples, including 196 from colorectal cancer patients, 122 from adenoma patients, and 179 from normal individuals, using real-time methylation-specific PCR. The impacts of one quantitative partial stool sampling device and 17 potentially interfering substances on the performance of fecal methylated SDC2 were also analyzed. SDC2 expression was also measured.Results:SDC2 methylation level was higher in 96.8% (120/124) of colorectal cancer tissues compared with paired adjacent normal epithelia. Stool test of methylated SDC2 detected 81.1% (159/196) of colorectal cancer and 58.2% (71/122) of adenomas at a specificity of 93.3% (167/179). No significant difference was found between partial and whole stool collection on colorectal cancer detection (P > 0.05, R² = 0.80). Among 17 interfering substances, only berberine at high concentrations inhibited fecal detection of methylated SDC2SDC2 was overexpressed in colorectal cancer tissues compared with normal epithelia.Conclusions: Fecal methylated SDC2 is a valuable biomarker for the noninvasive detection of colorectal neoplasms.Impact: Stool DNA test of methylated SDC2 would serve as an alternative method for screening colorectal neoplasms. Cancer Epidemiol Biomarkers Prev; 26(9); 1411-9. ©2017 AACR.

Improving Adherence to Screening Colonoscopy Preparation and Appointments: A Multicomponent Quality Improvement Program

Colorectal screening for cancer by colonoscopy is recommended for adults 50 years and older. Scheduling patients for sedated endoscopic procedures involves balancing physician schedules, room availability and equipment, proper patient preparedness, and necessary personnel. Both nonattendance and poor preparations contribute to inefficiency, wasted resources, and increased costs. We noted nonattendance rates ranging from 21% to 29%. As a first step, we examined patient factors associated with nonattendance using a retrospective case control study. Younger patients (<60 years), screening appointment, and insurance type were associated with nonattendance. On the basis of these findings, initial efforts focused on additional nurse strategies of follow-up contact and education for screening colonoscopies. As we improved attendance rate, concomitantly we discovered cancellation rates increasing. Subsequently, an interdisciplinary and interdepartmental quality improvement program has been ongoing to target a number of system-, nurse-, and patient-specific factors contributing to nonattendance and cancellations due to poor preparations. Rates have improved but require ongoing monitoring and surveillance. We describe the ongoing efforts and challenges aimed at both nonattendance and cancellations.

Effect of education on knowledge, attitude and behavioral intention in family relative with colorectal cancer patients based on theory of planned behavior

BACKGROUND

Colorectal cancer is one of most common cancers in women and men and one of the major causes of death due to neoplasia. Colonoscopy is considered as the most accurate diagnostic procedure to detect colorectal cancer at the earlier stages.

OBJECTIVES

The current study aimed to evaluate the effects of an education program using the Theory of Planned Behavior on promoting behavioral intention among first degree relatives of colorectal cancer patients.

MATERIALS AND METHOD

A quasi-experimental study conducted to evaluate the effectiveness of an educational program to promote attitudinal factors associated with early detection of colorectal cancer in 99 first degree relatives of colorectal cancer patients aged more than 20 years in Yazd city, Iran. A researcher made questionnaire forwhich validity and reliability were confirmed by expert point of view and pilot testing was employed for data collection. Questionnaires were filled in before and after educational intervention. The registered data were transferred to SPSS 19 and analyzed by paired T-test, Man-Whitney and Wilcaxon.

RESULTS

Mean scores of knowledge, attitude, perceived behavioral control and intention regarding colorectal cancer increased after education significantly (P<0.05).

CONCLUSIONS

Application of the Theory of Planned Behavior has positive influence on promoting intention behavior. It is therefore recommended to apply educational programs to promote behavioral intention.

How to improve colon cancer screening rates

Colorectal carcinoma is a common cause of death throughout the world and may be prevented by routine control, which can detect precancerous neoplasms and early cancers before they undergo malignant transformation or metastasis. Three strategies may improve colon cancer screening rates: convince the population about the importance of undergoing a screening test; achieve higher efficacy in standard screening tests and make them more available to the community and develop new more sensitive and efficacious screening methods and make them available as routine tests. In this light, the present study seeks to review these three means through which to increase colon cancer screening rates.

Impact of a Multifaceted Intervention on Promoting Adherence to Screening Colonoscopy Among Persons in HIV Primary Care: A Pilot Study

HIV-positive patients have lower colon cancer screening rates and are at increased risk for colon adenocarcinoma. We tested a transdisciplinary prevention model to increase provider and patient adherence to screening colonoscopy. Of 1,339 HIV-positive patients with scheduled clinic appointments during the period September to November 2009, we identified 400 records of eligible patients ≥50 years and retrospectively reviewed for screening colonoscopy referral; if never referred, flagged for referral at next visit. Providers referred 43.5% (174/400) patients and 36.2% (63/174) kept appointment. Within 6 months before the study, 337 patients attended clinic and providers referred 18%. Note that 211/226 patients with flagged records attended clinic at least once during the study 6-month period and providers referred (43.6%). The referral rate for flagged records was significantly different from that for the prior 6 months (p < 0.0001). A randomized trial compared the efficacy of patient decision support versus usual care on screening adherence. Among patients randomized to intervention 17 (51.5%) compared to usual care only 16 (48.5%), intervention group showed significant adherence of 70.6% (12/17) versus 29.4% (5/16), (p = 0.024). In addition, intervention patients had good bowel preparation of 76.9% (10/13) versus usual care 23.1% (3/13), (p = 0.05). This transdisciplinary intervention model significantly increased provider and patient screening colonoscopy behavior.

Cost-effectiveness of colorectal cancer screening protocols in urban Chinese populations

Colorectal cancer (CRC) takes a second and fourth position in the incidence and mortality lists respectively among all malignant tumors in urban populations in China. This study was designed to evaluate the cost-effectiveness of two different CRC screening protocols: faecal occult blood test (FOBT) alone, and FOBT plus a high-risk factor questionnaire (HRFQ) as the respective initial screens, followed by colonoscopy. We developed a Markov model to simulate the progression of a cohort of 100,000 average risk asymptomatic individuals moving through a defined series of states between the ages of 40 to 74 years. The parameters used for the modeling came from the CESP (Comparison and Evaluation of Screening Programs for Colorectal Cancer in Urban Communities in China) study and published literature. Eight CRC screening scenarios were tested in the Markov model. The cost-effectiveness of CRC screening under each scenario was measured by an incremental cost-effectiveness ratio (ICER) compared with a scenario without CRC screening. The study revealed that a combined use of FOBT and HRFQ is preferable in CRC screening programs as an initial screening instrument. Annual FOBT+HRFQ screening is recommended for those who have a negative initial result and those who have a positive result but have failed to continue to colonoscopic examination. Repeated colonoscopy (for those with a positive result in initial screening but a negative colonoscopy result) should be performed at a ten-year interval instead of one-year. Such a protocol would cost 7732 Yuan per life year saved, which is the most cost-effective option. In conclusion, the current Chinese Trial Version for CRC Screening Strategy should be revised in line with the most cost-effective protocol identified in this study.

Demonstration of a sucrose-derived contrast agent for magnetic resonance imaging of the GI tract

A scaffold bearing eight terminal alkyne groups was synthesized from sucrose, and copies of an azide-terminated Gd-DOTA complex were attached via copper(I)-catalyzed azide-alkyne cycloaddition. The resulting contrast agent (CA) was administered by gavage to C3H mice. Passage of the CA through the gastrointestinal (GI) tract was followed by T1-weighted magnetic resonance imaging (MRI) over a period of 47h, by which time the CA had exited the GI tract. No evidence for leakage of the CA from the GI tract was observed. Thus, a new, orally administered CA for MRI of the GI tract has been developed and successfully demonstrated.

Serum M2-pyruvate kinase: A promising non-invasive biomarker for colorectal cancer mass screening

AIM: To explore the value of serum M2-pyruvate kinase (M2-PK) in colorectal cancer (CRC) mass screening.

METHODS: We conducted a molecular epidemiology study in Hangzhou, China, from year 2006 to year 2008. Serum samples were collected from 93 CRC, 41 advanced adenomas, 137 adenomas, 47 non-adenomatous polyps, and 158 normal participants in a community setting. Serum M2-PK and carcinoembryonic antigen (CEA) were measured using Enzyme-linked immunosorbent assay. SPSS 16.0 software was used to perform data analysis. Area under the receiver operating characteristic curve (AUC), sensitivity, and specificities were estimated for serum M2-PK in diagnosis of colorectal lesions and compared with CEA.

RESULTS: Average serum M2-PK value among 158 normal people was 2.96 U/mL and not affected by gender (P = 0.47) or age (P = 0.59). Average serum M2-PK (U/mL) was 14.75 among stage III and 13.10 among stage I and II CRC patients, about 4 times higher than that among normal people. Average serum M2-PK was 8.58, 6.70, 5.13 and 2.51 U/mL among advanced adenoma, adenomas, non-adenomatous polyps, and inflammatory bowel disease patients, respectively. AUC for serum M2-PK was greater than that for CEA among all colorectal lesions. AUC for serum M2-PK was 0.89 (0.84, 0.94) (95% confidence interval), higher than that for CEA [0.70 (0.62-0.79)] in CRC stage I and II, 0.89 (0.84-0.94) vs 0.73 (0.63-0.83) in CRC stage III, 0.81 (0.74-0.86) vs 0.63 (0.53 - 0.73) in advanced adenomas, 0.69 (0.64-0.76) vs 0.54 (0.47-0.60) in adenomas, and 0.69 (0.62-0.78) vs 0.58 (0.48-0.68) in non-adenomatous polyps. The diagnostic sensitivity for all colorectal lesions increased with decrease in the cut-off value of serum M2-PK. The diagnostic sensitivity (%) of serum M2-PK was 100.00 for CRC, 95.12 advanced adenoma, 82.48 adenoma, and 82.98 non-adenomatous polyp. There were no CRC cases missed and 40.51% of unnecessary colonoscopies were avoided when the cut-off value was 2.00 U/mL.

CONCLUSION: Serum M2-PK can be used as a primary screening test in CRC mass screening. It may be a promising non-invasive biomarker for CRC early detection.

CT colonography may improve colorectal cancer screening compliance

OBJECTIVE

While colonoscopy is currently the preferred test for colorectal cancer (CRC) screening, the invasive and time-consuming characteristics of the test are often cited as reasons for noncompliance with screening. CT colonography (CTC) is a less invasive screening method that is comparable to colonoscopy for the detection of advanced neoplasia. The aim of this project was to assess patient preferences between colonoscopy and CTC in an open access system.

MATERIALS AND METHODS

Two hundred fifty consecutive average-risk patients undergoing CRC screening completed a survey that assessed reasons for choosing CTC in lieu of colonoscopy, compliance with CRC screening if CTC was not offered, and which of the two tests they preferred.

RESULTS

The most common reasons for undergoing CTC included convenience (33.6%), recommendation by referring provider (13.2%), and perceived safety (10.8%). Had CTC not been an available option, 91 of the 250 patients (36%) would have foregone CRC screening. Among the 57 patients who had experienced both procedures, 95% (n = 54) preferred CTC.

CONCLUSION

These findings show the importance of providing CTC as an alternative screening option for CRC at our institution, which may increase CRC adherence screening rates.

Performance value of high risk factors in colorectal cancer screening in China

AIM: To analyze the performance value of high risk factors in population-based colorectal cancer (CRC) screening in China.

METHODS: We compared the performance value of the immunochemical fecal occult blood test (iFOBT) and other high risk factors questionnaire in a population sample of 13 214 community residents who completed both the iFOBT and questionnaire investigation. Patients with either a positive iFOBT and/or questionnaire were regarded as a high risk population and those eligible were asked to undergo colonoscopy.

RESULTS: The iFOBT had the highest positive predictive value and negative predictive value in screening for advanced neoplasia. The iFOBT had the highest sensitivity, lowest number of extra false positive results associated with the detection of one extra abnormality for screening advanced neoplasias and adenomas. A history of chronic cholecystitis or cholecystectomy, chronic appendicitis or appendectomy, and chronic diarrhea also had a higher sensitivity than a history of adenomatous polyps in screening for advanced neoplasias and adenomas. The sensitivity of a history of chronic cholecystitis or cholecystectomy was highest among the 10 high risk factors in screening for non-adenomatous polyps. A history of chronic appendicitis or appendectomy, chronic constipation, chronic diarrhea, mucous and bloody stool, CRC in first degree relatives, malignant tumor and a positive iFOBT also had higher sensitivities than a history of adenomas polyps in screening for non-adenomatous polyps. Except for a history of malignant tumor in screening for non-adenomatous polyps, the gain in sensitivity was associated with an increase in extra false positive results associated with the detection of one extra abnormality.

CONCLUSION: The iFOBT may be the best marker for screening for advanced neoplasias and adenomas. Some unique high risk factors may play an important role in CRC screening in China.