Mass Screening For Colorectal Cancer Research Articles

COLORECTAL CANCER SCREENING “LITERATURE REVIEW”

According to the World Health Organization (WHO), screening consists of presumptively identifying, using tests appliedin a systematic and standardized manner, subjects suffering from a previously past disease or abnormality. unnoticed.Screening tests must make it possible to divide people who are apparently healthy but who are probably suffering from agiven disease or abnormality from those who are probably free from it, Four controlled population studies were carriedout in Europe to test the feasibility and effectiveness of mass screening for colorectal cancer: Nottingham (Great Britain),Funen (Denmark), Burgundy (France) and Gothenburg (Sweden). . The first three studies included subjects aged 45 or50 to 74 years old. The Hemoccult test was offered every 2 years to half of the target population, the other half served asa control. The Swedish study, involving subjects aged 60 to 64, is of limited interest because the screening test was onlycarried out twice with simple follow-up afterwards

Epidemiological and Histological Characteristics of Polyps Detected with Positive Tests During Mass Screening in the Wilaya of Béjaia

Detection of polyps during screening colonoscopy has improved significantly in recent years. This results in an increase in the detection rate of adenomas thanks in particular to technological innovations ( chromoendoscopy with indigo carmine or electronic) and the training of gastroenterologists, which is inversely correlated with the occurrence of colorectal cancer. The main objective of our study is to describe the epidemiological profile and histological characteristics of polyps and adenomas detected during a mass screening operation for colorectal cancer in a healthy population in the wilaya of Bejaia. The total number of polyps found in our target population is 196 in 89 people. A person can have a minimum of 1 polyp and a maximum of 6 polyps, the average number of polyps per person is 2 polyps, 43% of the population participating in mass screening for colorectal cancer have at least one polyp and 28% have two polyps.

Paper-Based versus Mobile Apps for Colorectal Cancer Screening in COVID-19 Pandemic Setting

Background: The incidence of colorectal cancer (CRC) in Asia has kept increasing in the last decade. The morbidity and mortality for CRC can be reduced with early detection; however, mass CRC screening with imaging modalities such as colonoscopy, CT scan, or MRI is unfeasible in developing countries such as Indonesia. Asia Pacific Colorectal Screening (APCS) is utilized to stratify individual CRC risk. Online screening via mobile application is an alternative method to ensure the continuity of community screening without risking COVID-19 transmission. Objective: We conducted a descriptive study to evaluate CRC risk using APCS in two different villages. Methods: This is a cross-sectional study involving 925 and 207 subjects in 2019 and 2020, respectively. The APCS survey in 2019 was done before the COVID-19 pandemic with paper-based questionnaires and direct assessment by door-to-door approach. Meanwhile, the APCS survey in 2020 was done during the COVID-19 pandemic using websites and mobile apps available for Android and iOS. We gathered participants’ characteristics and the APCS score in both groups and tabulated them. Results: In 2019, out of 925 subjects; 472 (51%) have been classified an average risk of CRC, 370 (40%) have been classified as having a moderate risk of CRC, and 83 (9%) have been classified as in high risk of CRC. In 2020, out of 207 subjects; 106 (51.2%) have been classified as the average risk of CRC, 86 (41.5%) have been classified as the moderate risk of CRC, and 15 (7.3%) have been classified as high risk of CRC. Conclusion: Although there was a decrease in the participation of the screening program with mobile applications in the pandemic era compared with paper-based questionnaires before the pandemic era, online screening using APCS in mobile applications is a preferred alternative for an effective screening method in this pandemic and possibly in the future in Indonesia.

Improved risk scoring systems for colorectal cancer screening in Shanghai, China

BackgroundAn optimal risk‐scoring system enables more targeted offers for colonoscopy in colorectal cancer (CRC) screening. This analysis aims to develop and validate scoring systems using parametric and non‐parametric methods for average‐risk populations.MethodsScreening data of 807,695 subjects and 2806 detected cases in the first‐round CRC screening program in Shanghai were used to develop risk‐predictive models and scoring systems using logistic‐regression (LR) and artificial‐neural‐network (ANN) methods. Performance of established scoring systems was evaluated using area under the receiver operating characteristic curve (AUC), calibration, sensitivity, specificity, number of high‐risk individuals and potential detection rates of CRC.ResultsAge, sex, CRC in first‐degree relatives, chronic diarrhoea, mucus or bloody stool, history of any cancer and faecal‐immunochemical‐test (FIT) results were identified as predictors for the presence of CRC. The AUC of LR‐based system was 0.642 when using risk factors only in derivation set, and increased to 0.774 by further incorporating one‐sample FIT results, and to 0.808 by including two‐sample FIT results, while those for ANN‐based systems were 0.639, 0.763 and 0.805, respectively. Better calibrations were observed for the LR‐based systems than the ANN‐based ones. Compared with the currently used initial tests, parallel use of FIT with LR‐based systems resulted in improved specificities, less demands for colonoscopy and higher detection rates of CRC, while parallel use of FIT with ANN‐based systems had higher sensitivities; incorporating FIT in the scoring systems further increased specificities, decreased colonoscopy demands and improved detection rates of CRC.ConclusionsOur results indicate the potentials of LR‐based scoring systems incorporating one‐ or two‐sample FIT results for CRC mass screening. External validation is warranted for scaling‐up implementation in the Chinese population.

PT1 Colorectal Cancer Detected in a Colorectal Cancer Mass Screening Program: Treatment and Factors Associated with Residual and Extraluminal Disease.

Simple SummaryOur study has evaluated the burden of pT1 CRC (confined to submucosa) detected during the first round of a CRC screening program, the surgery related complications and the factors related to four relevant outcomes: initial endoscopic resection, surgery rescue and residual disease after endoscopic resection and, finally, extraluminal disease after surgical resection. 38% of the CRC were detected in this stage.74.9% were initially resected endoscopically and 43.8% did not require surgery. There were inhospital surgical complications in 30.7%, mainly mild with no death and complications after discharge in 16.3% of the patients Residual disease was detected in 12 (4.3%) after endoscopic resection and extraluminal disease in 18 (8.6%) patients after surgery. We have determined several variables independently associated with the four outcome variables evaluated.The aim of this study is to describe the treatment of pT1 colorectal cancer (CRC) in a mass screening program, the surgery-related complications and the factors associated with residual disease after endoscopic resection and extraluminal disease after surgery. We included in this retrospective analysis all the pT1 CRC detected in the Galician CRC screening program between May 2013 and June 2019. We determined which variables were independently associated with the outcomes of the study through a multivariable logistic regression analysis. We included 370–354 pT1 N0(X), 16 pT1N1- out of the 971 CRC detected; 277 (74.9%) were resected endoscopically and 162 (43.8%) were not referred to surgery. There were surgical complications in 30.7% and 16.3% of the patients during hospitalization and after discharge. Residual disease was detected in 12 (4.3%) after endoscopic resection and extraluminal disease in 18 (8.6%) patients after surgery. The variables independently associated with initial endoscopic resection were a pedunculated morphology (OR 33.1, 95% CI 4.3–254), a diameter ≥ 20 mm (OR 3.94, 95% CI 1.39–11.18) and a Site–Morphology–Size–Access score < 9 (OR 428, 95% CI 42–4263). The variables related with surgery rescue were a piecemeal resection (OR 4.48, 95% CI 1.48–13.6), an infiltrated/nonevaluable resection border (OR 7.44, 95% CI 2.12–26.0), a non-well-differentiated histology (OR 4.76, 95% CI 1.07–20.0), vascular infiltration (OR 8.24, 95% CI 2.72–25.0) and a Haggitt 4 infiltration of the submucosa (OR 5.68, 95% CI 2.62–12.3). Residual disease after endoscopic resection was associated with an infiltrated/nonevaluable resection border (OR 34.9, 95% CI 4.08–298), a non-well-differentiated histology (OR 6.67, 95% CI 1.05–50.0), and the vascular infiltration of the submucosa (OR 7.61, 95% CI 1.55–37.4). The variables related with extraluminal disease after surgical resection were no endoscopic resection (OR 4.34, 95% CI 1.26–14.28), a non-well-differentiated histology (OR 4.35, 95% CI 1.39–14.29) and the lymphatic infiltration of the submucosa (OR 4.8, 95% CI 1.32–17.8). In a CRC screening program, although most of pT1 CRC are candidates for endoscopic treatment, surgery is a safe procedure. We have defined some easy to evaluate variables that can be used in the decision-making process.

Development of a new mathematical tool for early colorectal cancer diagnosis and its possible use in mass screening

The aim of the study is to model a new mathematical tool effective in the diagnosis of colorectal cancer and useful as a mass screening test. This work enrolled 345 subjects from January 2011 to January 2013, in 4 Italian Surgical Departments: 97 (27,4%) out of the total were healthy controls (class 0) whereas 248 (72,6%) patients were affected by colorectal cancer. The cancer patients were divided into four classes, according to TNM staging classification: 74 (20,9%) patients stage I (class 1); 61 (17,2) patients stage II (class 2); 76 (21,5%) patients vstage III (class 3); 37 (10,5%) stage IV (class 4).Blood samples were collected after 24h from hospital admission and 17 biochemical parameters (CEA, ceruloplasmin, haptoglobin, transferrin, TPA, CA 19.9, CA 72.4, PCR, Ca 50, C4 Complement, CA 125, Alfa-1-antitrypsin, alpha-2-Macroglobulin, Ferritin, RBP, Alpha-1-Acid Glycoprotein, Complement C3) were statistically analysed together with the clinical and pathological disease staging (pre and postoperative evaluation, respectively). Evaluation and comparison were made between two groups: healthy controls and the total of affected patients.Using the collected data, it was developed a mathematical model (artificial neural network ANN) allowing the distribution of colorectal cancer and controls (apparently in good health) patients in the two groups. This led to the definition of an index (B-index) that, simply analysing the combined values of the 17 biochemical parameters, decides on the either healthy or disease status of the patient. The use of the B-index, with a neural network based on real values, allows colorectal cancer diagnosis with 80.078% accuracy, probability of false positive (FP) = 0.333, probability of false negatives (FN) = 0.102, a 0.898 sensitivity and 0.667 specificity. However, by using B-index with a neural network based on the implementation of extended reality values our analysis reaches an accuracy of 91.11% in colorectal cancer diagnosis, with probability of false positive (FP) = 0.472, probability of false negatives (FN) = 0.03%, a 0.9997 sensitivity and 0.7642 specificity. The results suggest a promising role for B-index in colorectal cancer mass screening with an easily available, low cost and non-invasive test.

Mass screening for colorectal cancer in a population of two million older adults in Guangzhou, China

Screening is an effective measure to prevent and control colorectal cancer (CRC). A mass CRC screening programme was conducted in Guangzhou from 2015 to 2017. Public media and reminders from a mobile short message service were used to invite residents aged between 50 and 74 years. A high-risk factor questionnaire (HRFQ) and biennial faecal immunochemical testing (FIT) were chosen as the primary screening methods, and individuals with a positive test result were referred to a defined hospital for an assessment colonoscopy. During the 3 years, 350,581 residents of the total eligible population of 2,283,214 attended the free first stage of screening. In all, 91.0% of the participants finished the HRFQs and FITs. The total uptake rate was 15.4%, which increased with age, female sex, and rural location. There was 15.9% positivity in the first stage of screening, including 8.5% positive HRFQs, 6.2% positive FITs and 1.2% positive HRFQs and FITs. In total, 10,600 individuals with positive HRFQs/FITs completed an assessment colonoscopy. The total uptake rate of colonoscopies was 18.9%, which decreased with age and female sex. Three hundred fifty-one CRCs and 980 advanced adenomas (AAs) were diagnosed with positive predictive values (PPV) of 3.3% and 9.2%, respectively. The PPVs of CRCs in the exclusively FIT-positive population were 4.9%, which was 10 times greater than in the exclusively HRFQ-positive population (0.5%). The PPVs of CRCs and AAs increased with age and male sex. The detection ratio of localized CRCs (including stage I and stage II) increased 68.1% due to screening. Although the compliance rate was low, the PPVs for CRCs and AAs were high. More effective mobilization of the programme’s needs and subsidies for colonoscopies should be taken into account to increase compliance.

Sa1036 FOLLOW-UP COLONOSCOPY IN COLORECTAL CANCER SCREENING REMAINS EFFECTIVE AMONG ELDERLY INDIVIDUALS WHO SHOW POSITIVE FIT RESULTS

Both American College of Physicians and U.S. Preventive Services Task Force recommend for people aged 75 and over to consider stopping the screening for colorectal cancer (CRC). But in Japan, there is no guideline about the ages of CRC screening, a lot of people over 75 years are receiving fecal immunochemical test (FIT) for mass screening for CRC, and consequently, a good number of elderly people undergo a follow-up exam, colonoscopy (CS). Because CS has possible severe complications, the follow-up CS among elderly people should contribute to CRC screening no less than among younger people. We investigated the efficacy of the follow-up CS among individuals over 75 years old, by comparing the results of the follow-up CS with those among younger individuals. This retrospective study was carried out in a single center. A total of 1336 subjects (657 men; 679 women) who underwent CS based on the positive result of FIT were enrolled. After dividing them into two groups, over 75 years (group A, 589 subjects) and 75 years or less (group B, 747), the detection rate of CRC, the rate of invasive CRC, treatment methods, CRC sites, and the detection rate of any neoplasm (CRC or adenoma) were determined. χ2 test was used for statistical analysis. The detection rate of CRC showed no significant difference between group A and B (8.8%, 52 out of 589 subjects; 7.5%, 56 out of 747, respectively). However, the rate of invasive CRC was significantly higher in group A than B (69%, 36 out of 52 CRC subjects; 41%, 23 out of 56, respectively, P < 0.005). As a result, 58% in group A needed surgery, on the other hand, 34% in group B underwent surgery (P < 0.015), and the others were endoscopically treated. CRCs were more frequently detected in the right side colon in group A than B (59%, 32 out of total 54 CRC lesions; 28%, 17 out of 61, respectively, P < 0.005). There was no significant difference in the total neoplasm detection rate between group A and B (53%, 312 out of 589 subjects; 55%, 411 out of 747, respectively). Individuals over 75 years who underwent the follow-up colonoscopy showed no significant difference in the detection rates of CRC or neoplasm compared with the younger individuals. However, CRCs detected in the individuals over 75 years were more deeply invasive and were more frequently seen and predominant especially in the right side colon than the younger individuals, where CRC is thought to be more difficult in early detection without any symptoms than in the left side. Taken together, we believe that CRC screening after the age of 75, using FIT and the follow-up CS, may have some efficacy.

Predicting the risk for colorectal cancer with personal characteristics and fecal immunochemical test.

We aimed to predict colorectal cancer (CRC) based on the demographic features and clinical correlates of personal symptoms and signs from Tianjin community-based CRC screening data.A total of 891,199 residents who were aged 60 to 74 and were screened in 2012 were enrolled. The Lasso logistic regression model was used to identify the predictors for CRC. Predictive validity was assessed by the receiver operating characteristic (ROC) curve. Bootstrapping method was also performed to validate this prediction model.CRC was best predicted by a model that included age, sex, education level, occupations, diarrhea, constipation, colon mucosa and bleeding, gallbladder disease, a stressful life event, family history of CRC, and a positive fecal immunochemical test (FIT). The area under curve (AUC) for the questionnaire with a FIT was 84% (95% CI: 82%–86%), followed by 76% (95% CI: 74%–79%) for a FIT alone, and 73% (95% CI: 71%–76%) for the questionnaire alone. With 500 bootstrap replications, the estimated optimism (<0.005) shows good discrimination in validation of prediction model.A risk prediction model for CRC based on a series of symptoms and signs related to enteric diseases in combination with a FIT was developed from first round of screening. The results of the current study are useful for increasing the awareness of high-risk subjects and for individual-risk-guided invitations or strategies to achieve mass screening for CRC.

Computed tomography colonography for the practicing radiologist: A review of current recommendations on methodology and clinical indications.

Colorectal cancer (CRC) represents one of the most relevant causes of morbidity and mortality in Western societies. CRC screening is actually based on faecal occult blood testing, and optical colonoscopy still remains the gold standard screening test for cancer detection. However, computed tomography colonography (CT colonography) constitutes a reliable, minimally-invasive method to rapidly and effectively evaluate the entire colon for clinically relevant lesions. Furthermore, even if the benefits of its employment in CRC mass screening have not fully established yet, CT colonography may represent a reasonable alternative screening test in patients who cannot undergo or refuse colonoscopy. Therefore, the purpose of our review is to illustrate the most updated recommendations on methodology and the current clinical indications of CT colonography, according to the data of the existing relevant literature.

Cost-Effectiveness between Double and Single Fecal Immunochemical Test(s) in a Mass Colorectal Cancer Screening.

This study investigated the cost-effectiveness between double and single Fecal Immunochemical Test(s) (FIT) in a mass CRC screening. A two-stage sequential screening was conducted. FIT was used as a primary screening test and recommended twice by an interval of one week at the first screening stage. We defined the first-time FIT as FIT1 and the second-time FIT as FIT2. If either FIT1 or FIT2 was positive (+), then a colonoscopy was recommended at the second stage. Costs were recorded and analyzed. A total of 24,419 participants completed either FIT1 or FIT2. The detection rate of advanced neoplasm was 19.2% among both FIT1+ and FIT2+, especially high among men with age ≥55 (27.4%). About 15.4% CRC, 18.9% advanced neoplasm, and 29.9% adenoma missed by FIT1 were detected by FIT2 alone. Average cost was $2,935 for double FITs and $2,121 for FIT1 to detect each CRC and $901 for double FITs and $680 for FIT1 to detect each advanced neoplasm. Double FITs are overall more cost-effective, having significantly higher positive and detection rates with an acceptable higher cost, than single FIT. Double FITs should be encouraged for the first screening in a mass CRC screening, especially in economically and medically underserved populations/areas/countries.

PD-011 Inexpensive biomarkers for determining individuals at increased risk for colorectal cancer and hence have the repeat screening colonoscopy after the first normal earlier than guidelines recommend

Introduction: Screening for colorectal cancer (CRC) is currently based on colonoscopy and other methods such as the fecal occult blood test. We are interested in the role of blood-based genetic markers in CRC screening because of their low cost and relative nonintrusiveness. However, the performance of test strategies involving different numbers of markers of various properties needs further study.Methods: We have shown an association between colorectal cancer (185 cases vs. 93 controls) and SNP or deletion status for TGFBR1, GSTT1, INSR, telRNA, LRRC1, GSTM1, CHR8 and FOXO1. The information from all these tests was combined using a discriminant function. All information for each subject was condensed into a single index which gives the best discrimination between cases and controls. The index could be used to distinguish high-risk subjects from low-risk ones, so that the high-risk group would become the focus of further screening and early detection of cancer. Furthermore, various thresholds of the index could be defined to optimise the economic performance of the test for various relative costs of false positives or false negatives.Results: We have used data on the SNPs and deletions to enable us to evaluate the performance of the test based on different numbers of variants. The addition of variants led to increased sensitivity and specificity of the test. For example, with all eight markers the sensitivity was found to be 74.6% and the specificity 77.4%. With only three variants (TGFBR1, GSTT1 and INSR), sensitivity was 70.3% and specificity 67.7%.Conclusion: Presently the yield of mass screening for colorectal cancer has by its nature a vast number of persons of which the majority will not have cancer. Based on this fact, repeat screening after normal first colonoscopy has a low yield and still misses a certain number of intermediary cancers. By being able to predict a higher risk group, the repeat colonoscopy might have to be done earlier than stated by guidelines for these individuals. Although the cost of test with a panel of biomarkers depends on the number of markers and the particular ones chosen, a first estimate would be in the range $50 to $100 per individual, much less than the cost of a colonoscopy. Furthermore, the test could be carried out at any age, including much earlier than is recommended for colonoscopy. Introduction: Screening for colorectal cancer (CRC) is currently based on colonoscopy and other methods such as the fecal occult blood test. We are interested in the role of blood-based genetic markers in CRC screening because of their low cost and relative nonintrusiveness. However, the performance of test strategies involving different numbers of markers of various properties needs further study. Methods: We have shown an association between colorectal cancer (185 cases vs. 93 controls) and SNP or deletion status for TGFBR1, GSTT1, INSR, telRNA, LRRC1, GSTM1, CHR8 and FOXO1. The information from all these tests was combined using a discriminant function. All information for each subject was condensed into a single index which gives the best discrimination between cases and controls. The index could be used to distinguish high-risk subjects from low-risk ones, so that the high-risk group would become the focus of further screening and early detection of cancer. Furthermore, various thresholds of the index could be defined to optimise the economic performance of the test for various relative costs of false positives or false negatives. Results: We have used data on the SNPs and deletions to enable us to evaluate the performance of the test based on different numbers of variants. The addition of variants led to increased sensitivity and specificity of the test. For example, with all eight markers the sensitivity was found to be 74.6% and the specificity 77.4%. With only three variants (TGFBR1, GSTT1 and INSR), sensitivity was 70.3% and specificity 67.7%. Conclusion: Presently the yield of mass screening for colorectal cancer has by its nature a vast number of persons of which the majority will not have cancer. Based on this fact, repeat screening after normal first colonoscopy has a low yield and still misses a certain number of intermediary cancers. By being able to predict a higher risk group, the repeat colonoscopy might have to be done earlier than stated by guidelines for these individuals. Although the cost of test with a panel of biomarkers depends on the number of markers and the particular ones chosen, a first estimate would be in the range $50 to $100 per individual, much less than the cost of a colonoscopy. Furthermore, the test could be carried out at any age, including much earlier than is recommended for colonoscopy.

Efficacy of communication skills training on colorectal cancer screening by GPs: a cluster randomised controlled trial.

Colorectal cancer (CRC) mass screening has been implemented in France since 2008. Participation rates remain too low. The objective of this study was to test if the implementation of a training course focused on communication skills among general practitioners (GP) would increase the delivery of gaiac faecal occult blood test and CRC screening participation among the target population of each participating GP. A cluster randomised controlled trial was conducted with GP's practice as a cluster unit. GPs from practices in the control group were asked to continue their usual care. GPs of the intervention group received a 4-h educational training, built with previous qualitative data on CRC screening focusing on doctor-patient communication with a follow-up of 7 months for both groups. The primary outcome measure was the patients' participation rate in the target population for each GP. Seventeen GPs (16 practices) in intervention group and 28 GPs (19 practices) in control group participated. The patients' participation rate in the intervention group were 36.7% vs. 24.5% in the control group (P = 0.03). Doctor-patient communication should be developed and appear to be one of the possible targets of improvement patients adherence and participation rate in the target population for CRC mass screening.

Incidence of Colorectal Neoplasia in a High Risk Population Screened for Colorectal Cancer. Result of 5 Consecutives Mass Screening Campaigns in a Well-Defined Population

ABSTRACT Aim: Colorectal cancer mass screening with FOBT is implemented to screen average risk population aged 50–74 years. Some colorectal neoplasia history is revealed by the pre-screening procedure. Patients were so excluded from FOBT screening and then a screening colonoscopy was offered. We studied this population at high risk colorectal neoplasia naive for previous colorectal exploration, from 5 consecutive colorectal cancer screening campaigns. Methods: Variables: age, campaign, source of exclusion (general practitioner (GP) or gastroenterologist), colonoscopy completion rate, positive predictive value (PPV) of neoplasia (cancer, advanced adenoma, adenoma). Results: 1179 patients studied (0.1-0.3% of the target population), mean age 59.7 years. Colonoscopy performed for 889 patients, complete in 97.5% of cases. In 68.1% of cases the history was revealed by the GP. Colonoscopy was achieved in 70% of cases when history was detected by the GP and in 87% when detected by the gastroenterologist. 253 Colorectal neoplasias were diagnosed; 35 cancers (TNM stage 0-1: 74%, TNM stage 2: 9%, TNM stage 3: 14%, TNM stage 4: 3%), 14 resected endoscopically; one or more adenomas diagnosed in 219 patients and a total of 347 adenomas resected, endoscopically in 98.5% of cases. The average number of adenoma per patient was 2.1 (1 to 50) and the average size was 7.2 mm (1 to 75). Size was ≥10 mm for 38% of cases, 38.3% had a villous component and 7.9% were high grade dysplasia. A total of 209 advanced adenomas (size ≥ 10 mm and/or villous component and/or high grade dysplasia and/or number ≥ 3) were diagnosed in 122 patients. PPV of cancer was 3.9%, PPV of advanced adenoma was 12.9%, and PPV of adenoma was 25%. Conclusions: In this population with a history of colorectal neoplasia revealed by the mass screening campaign, the rate of participation in screening is very high (75.5%). The PPV of neoplasia is lower than in the average risk population selected by a positive FOBT (PPV of cancer range 7.5 to 10%, PPV of advanced adenoma range 15 to 27% and PPV of adenoma range 32 to 37% in our administrative area). This population might probably also benefit from screening with FOBT. Disclosure: All authors have declared no conflicts of interest.

Incidence of colorectal neoplasia in a high-risk population screened for colorectal cancer: Result of five consecutive mass screening campaigns in a well-defined population.

e12509 Background: Colorectal cancer mass screening with FOBT permit to screen average risk population aged 50-74 years. Some colorectal neoplasia history is revealed by the pre-screening procedure...

The cost-effectiveness of immunochemical tests for colorectal cancer screening

The optimal immunochemical test to use for generalised mass screening is still under debate in France. To compare the cost and effectiveness in biennial screening for colorectal cancer of fifteen strategies consisting of the three-stool sample un-rehydrated guaiac faecal occult blood test and three immunochemical tests: Magstream, FOB-Gold and OC-Sensor, at different positivity cut-off levels and stool-sample collection. A Markov model was used to compare these strategies in a general population of 100,000 individuals aged 50-74 over a 20-year period. Immunochemical tests were efficient strategies compared with guaiac faecal occult blood test. When all 15 strategies were compared with each other, only five of them remained efficient: the one- and two-stool sample Magstream, the one- and two-stool sample FOB-Gold with the 176 ng/mL cut-off, and the two-stool sample OC-Sensor with the 150 ng/mL cut-off. Sensitivity analyses showed that, at an identical price, the one-stool sample OC-Sensor was the most efficient strategy, and outperformed FOB-Gold. One-stool immunochemical testing can be considered a promising alternative to the guaiac faecal occult blood test for colorectal cancer mass screening in the general population. Competition between manufacturers should now be introduced to reduce purchase price differences.

The influence of waiting times on cost-effectiveness: a case study of colorectal cancer mass screening

When a cost-effectiveness analysis is implemented, the health-care system is usually assumed to adjust smoothly to the proposed new strategy. However, technological innovations in health care may often induce friction in the organization of care supply, implying the congestion of services and subsequent waiting times. Our objective here is to measure how these short run rigidities can challenge cost-effectiveness recommendations favorable to an innovative mass screening test for colorectal cancer. Using Markov modeling, we compare the standard Guaiac fecal occult blood test (gFOBT) with an innovative screening test for colorectal cancer, namely the immunological fecal occult blood test (iFOBT). Waiting time can occur between a positive screening test and the subsequent confirmation colonoscopy. Five scenarios are considered for iFOBT: no further waiting time compared with gFOBT, twice as much waiting time for a period of 5 or 10 years, and twice as much waiting time for a period of 5 or 10 years combined with a 25% decrease in participation to confirmation colonoscopies. According to our modeling, compared with gFOBT, iFOBT would approximately double colonoscopy demand. Probabilistic sensitivity analysis enables concluding that the waiting time significantly increases the uncertainty surrounding recommendations favorable to iFOBT if it induces a decrease in the adherence rate for confirmation colonoscopy.

Sequential Combination of Serum Pyruvate Kinase Isoenzyme M2 and Colonoscopy-A Promising Screening Protocol for Colorectal Cancer Early Diagnosis

Background: Early diagnosis and treatment through mass screening is practical against colorectal cancer (CRC). Low compliance for current screening tests affects the effectiveness of CRC mass screening. An efficient screening protocol with high compliance is needed for CRC mass screening. Methods: Systematic searches were done through Medline and Cochrane Library databases - initial Medline searches were in February 2010 and additional searches in March/April 2010. Search terms included [(“Colorectal cancer” AND “screening program” AND “incidence”) OR (“Colorectal cancer” AND “screening program” AND “mortality”)] AND [“fecal occult blood test” OR “sigmoidoscopy” OR “colonoscopy” OR “Double-contrast barium enema”]. Results: This review explored the current CRC mass screening protocols to find a more efficient and practical mass screening protocol and problems suitable for further research. Considering the current economic crisis and limited available resources, combination of high risk factor questionnaire and immunochemical fecal occult blood test approach as primary CRC mass screening can currently be used as a risk stratification tool to identify high-risk populations from the community, especially for medically and economically underserved areas/countries before a new better test comes. Using serum Pyruvate Kinase Isoenzyme M2 (M2-PK) as primary and colonoscopy as secondary screening test sounds more efficient with higher compliance than current CRC mass screening protocols. Conclusion: Recommendations for CRC mass screening are suggested for each risk population based on risk stratification. Serum M2-PK- may be developed as a promising CRC primary mass screening test. Sequential combination of serum biomarker such as Pyruvate Kinase Isoenzyme M2 (M2-PK) and colonoscopy can be a promising CRC mass screening protocol.

免疫学的便潜血反応 (逆受身血球凝集法: RPHA法) による大腸癌集検

免疫学的便潜血反応 (逆受身血球凝集法: RPHA法) による大腸癌集検

大腸がん検診とセットにしたペプシノゲン法 (PG法) による胃がん検診の試み

大腸がん検診とセットにしたペプシノゲン法 (PG法) による胃がん検診の試み