How do women comply with cancer screenings? A study in four regions of France.

BACKGROUND: This article looks at the behaviour of women facing different cancer screening options available to them from the age of 50 onward. The study was conducted in 2019 in four departments of the French territory with the objective of identifying the factors that influence acceptance of a population-based screening proposal. METHODS: A questionnaire was sent to women who had received three invitations to organised screenings (OS) for both breast and colorectal cancer. The categories of participants in both OS were designed from data from the regional cancer screening coordination centres in each department. Participation in opportunistic cervical cancer screening was evaluated as self-reported data. RESULTS: 4,634 questionnaires were returned out of the 17,194 sent, giving a global return rate of 27%. The highest rate of return (73.5%) was obtained from women who had participated at least once in both breast and colorectal cancer OS. An intermediate rate was obtained from women participating in breast cancer OS only (18.7%). Poor levels of return came from women who had participated in colorectal cancer OS only (3.6%) and from non-participants (4.1%). Our results suggest that women with lower educational levels tend to be the most regular attendants at OS (50.3%), compared to highly educated women (39.7%). 11.8% of women were overdue in their opportunistic cervical cancer screening. This percentage rose to 35.4% in the category of non-participants. In addition, women's comments provide a better understanding of the reasons for irregular attendance and non-participation. CONCLUSION: Overall, similar behaviours towards screening were observed in the four departments. Our analysis suggests that participation in one cancer OS increases the likelihood of participating in others. This adhesion could be an interesting lever for raising women's awareness of other cancer screenings.

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

BACKGROUND AND AIMS: We aimed to evaluate the effects of switching to faecal immunochemical testing (FIT) on the cumulative 2-year incidence rate of interval cancers, interval cancer rate and test sensitivity within a mature population-based colorectal cancer screening programme consisting of six rounds of biennial guaiac faecal occult blood testing (gFOBT). METHODS: The FIT results were compared with those of gFOBT used in each of the previous two rounds. For the three rounds analysed, 279,041 tests were performed by 156,186 individuals. Logistic regression analysis was used to determine interval cancer risk factors (Poisson regression) and to compare the sensitivity of FIT to gFOBT. RESULTS: There were 612 cases of screen-detected cancers and 209 cases of interval cancers. The sex- and age-adjusted cumulative 2-year incidence rates of interval cancers were 55.7 (95% CI, 45.3-68.5), 42.4 (95% CI, 32.6-55.2) and 15.8 (95% CI, 10.9-22.8) per 100,000 person-years after the last two rounds of gFOBT and FIT, respectively. The FIT/gFOBT incidence rate ratio was 0.38 [95% CI, 0.27-0.54] (P < 0.001). Sex- and age-adjusted sensitivity was significantly higher with FIT than with gFOBT (OR = 6.70 [95% CI, 4.48-10.01], P < 0.0001). CONCLUSIONS: This population-based study revealed a dramatic decrease in the cumulative incidence rates of interval cancers after switching from gFOBT to FIT. These data provide an additional incentive for countries still using gFOBT to switch to FIT.

Reappraisal of the characteristics, management, and prognosis of intramucosal colorectal cancers and their comparison with T1 carcinomas.

BACKGROUND AND AIMS: The recent description of "invasive" forms of intramucosal carcinoma (IMC) has rekindled interest in studying the characteristics, management, and prognosis of IMCs and comparing them with T1 colorectal cancers (CRCs). METHODS: This population-based study included 282 cases of IMC and 207 cases of T1 CRC diagnosed by colonoscopy after a positive fecal blood test through a screening program. RESULTS: IMC presented mainly in the form of pedunculated polyps (68.4%) located in the distal colon (69.9%) ≥20 mm in size (60.6%). IMCs were resected endoscopically in 227 (80.5%) patients and surgically resected in 55 (19.5%) patients. Surgical patients had more right-sided, more sessile, and larger lesions. There was no sign of lymphovascular invasion. Compared with T1 CRCs, IMCs demonstrated lower rates of sessile polyps (31.6% vs 49.8%, P < .0001), primary and ultimate surgical treatment (19.5% vs 39.1% and 19.9% vs 78.7%, P < .0001, respectively), lymph node metastasis in surgical patients (0% vs 9.5%, P = .041), cancer recurrence and cancer-related mortality (0% vs 5.6% and 0% vs 2.5%, respectively), and bleeding after endoscopic resection (1.8% vs 8.7%, P = .001). By multivariate analysis of the pooled cohort (IMC + T1 CRC, n = 489), the factors significantly associated with first-line surgery were shown to be polyp characteristics and the gastroenterologist who performed the colonoscopy. CONCLUSIONS: IMCs account for a quarter of all screening-detected CRCs. They have an excellent prognosis regardless of whether endoscopic or surgical treatment is performed. IMCs differ significantly from T1 carcinomas in terms of management and prognosis.

Frequency of and risk factors for the surgical resection of nonmalignant colorectal polyps: a population-based study.

BACKGROUND AND STUDY AIMS: The management of patients with colon polyps who are referred to surgery remains uncharacterized in a population-based setting. The aims of this study were to determine the frequency, risk factors, and outcomes of patients referred for surgical resection of colorectal polyps. PATIENTS AND METHODS: All patients who underwent a colonoscopy for positive fecal occult blood test in the setting of a population-based colorectal cancer screening program in France between 2003 and 2012 were analyzed. The primary outcome was the proportion of patients undergoing colorectal surgery for polyps without invasive carcinoma. Logistic regression analysis was applied to identify risk factors for surgical resection. RESULTS: Among 4251 patients with at least one colorectal polyp, 175 (4.1 %) underwent colorectal surgery. Risk factors for surgery included size, proximal polyp location, advanced histology (villous or high grade dysplasia), the endoscopy center, and colonoscopy performed during the first half of the study period. Subgroup analysis of 3475 colonoscopies performed by 22 endoscopists who performed at least 50 colonoscopies during the study period, identified the endoscopist as an additional risk factor. The adjusted proportions of referrals to surgery ranged from 0 to 46.6 % per endoscopist for polyps ≥ 20  mm (median 20.2 %). Overall, surgical complications occurred in 24.0 %, and one patient died following surgery (0.5 %). None of the 175 patients who underwent surgery were referred to a tertiary endoscopic center prior to surgery. CONCLUSIONS: In this population-based study, 4.1 % of patients with nonmalignant polyps were referred for surgical resection. The endoscopist was one important factor that was associated with surgical referral. To further decrease the proportion of inappropriate surgery in patients, endoscopists should refer their patients with large or difficult polyps to expert endoscopists prior to surgery.

Estimating the number of sudden cardiac deaths attributable to the use of domperidone in France.

PURPOSE: The aim of this study was to estimate of the number of sudden cardiac deaths attributable to the use of domperidone in France in 2012 METHODS: Computation of the attributable fraction, function of the increase in risk of sudden cardiac death induced by domperidone and of the exposure prevalence. Multiplying the attributable fraction by the risk of sudden cardiac death in the French population gives an estimation of the number of sudden cardiac deaths attributable to domperidone. RESULTS: The use of domperidone in France is the cause of 231 deaths per year in the population aged 18 years or over. CONCLUSIONS: This risk should be taken into consideration by clinicians when prescribing a drug which provides a minor benefit.

Measurement of adenoma detection and discrimination during colonoscopy in routine practice: an exploratory study.

BACKGROUND: Measuring neoplasia yield is a priority in the quality improvement process for colonoscopy. However, neither the most appropriate quality indicator nor the standard threshold has been established. OBJECTIVE: To determine the most appropriate quality indicators to assess the yield of routine colonoscopy. DESIGN: Retrospective. SETTING: Population-based colorectal cancer screening program in 3 French administrative areas. SUBJECTS: One hundred gastroenterologists and their average-risk asymptomatic patients aged 50 to 74 years undergoing colonoscopy for positive guaiac-based fecal occult blood test results. MAIN OUTCOME MEASUREMENTS: Comparison of several indicators, mainly the adenoma detection rate (ADR) and polyp detection rate (PDR), the mean number of adenomas per colonoscopy (MNA) and mean number of polyps (MNP) and the proportion of adenomas among polyps (PAP). RESULTS: Correlations were good between the ADR and PDR (Pearson coefficient r = 0.88 [95% CI, 0.78-0.94]) and between MNA and MNP (r = 0.89 [95% CI, 0.79-0.94]) (P < .0001 for both). Gastroenterologists were classified as higher or lower detectors in comparison with the lower limit of the 95% confidence interval of the median value for each indicator. The MNP (MNA) provided better discrimination than the PDR (ADR). Concordance between classifications of gastroenterologists according to their MNA and MNP was excellent (κ = 0.89). PAP varied dramatically from 38% to 95% between gastroenterologists and was very poorly correlated with the ADR (r = -0.27 [95% CI, -0.54 to 0.07; P = .11]) and the MNA (r = 0.03 [95% CI, -0.29 to 0.36; P = .88]). LIMITATIONS: Some factors influencing the neoplasia yield were not taken into account. CONCLUSIONS: The MNP could replace the ADR for the assessment of adenoma detection in routine practice. A separate indicator, PAP, would be necessary to assess adenoma discrimination ability.

Neoplasia detection rates after positive fecal occult blood test results are not affected by endoscopy center: a population-based study.

BACKGROUND: We previously showed a significant variability in adenoma detection among colonoscopists who were participating in a mass screening program. The reasons for such variability remain largely unknown. OBJECTIVE: To study intercenter variations in neoplasia detection. DESIGN AND SETTING: Secondary analyses of colonoscopy findings from the 2 first rounds of a French screening program: logistic regressions and repeated-measures analyses of variance. MATERIAL: A total of 3487 colonoscopies performed by all 19 endoscopists who performed 30 examinations or more per round at 8 centers (6 private, 2 public). MAIN OUTCOME MEASUREMENTS: Probabilities of detecting 1, 2, or 3 or more adenomas, 1 adenoma 10 mm or larger, or colorectal cancer, as well as the corresponding adjusted (for patient age and sex) per-center detection rates. RESULTS: Endoscopy centers were not significant predictors of the probability of detecting any category of neoplasia with the exception of the 2 adenomas or more category (P < .005). The ranges of the adjusted detection rates for each of these categories were 33.1% to 43.1%, 11.1% to 21.6%, 3.6% to 8.1%, 16.3% to 23.6%, and 8.3% to 12.6%, respectively. When the colonoscopies that were performed by the 11 endoscopists who performed 30 examinations or more per center in 2 or more centers were separately analyzed, no intercenter statistically significant variability was observed with the exception of 1 endoscopist and the 1 adenoma category. In a subgroup of 1100 colonoscopies performed by 6 endoscopists who were working at the same 3 centers, intercenter variability was not statistically significant. LIMITATIONS: Type II error because of sample sizes. CONCLUSIONS: In our setting, intercenter variability did not explain interendoscopist variability for neoplasia detection rate.

Surgical rather than endoscopic resection of early-stage colorectal cancers promotes excessive imaging surveillance.

BACKGROUND AND AIMS: Imaging surveillance after curative resection of colorectal cancer (CRC) is debated, particularly in cases of early-stage CRC. The aim of this study was to retrospectively analyze whether and how patients with screened stage 0 and stage 1 CRC were monitored by imaging. METHODS: A cohort of patients with stage 0 (intramucosal) or stage 1 (T1N0) CRC detected from 2003 to 2015 through the French national screening programme was included. All imaging findings were recorded. Statistical analyses were performed for the entire cohort (n = 450) and separately for the two groups (stage 0 n = 268, stage 1 n = 182). Factors associated with imaging surveillance, including the patient's referring gastroenterologist, were determined by logistic regression. RESULTS: A total of 450 patients were followed up for 6.6 ±â€¯3.9 years. Imaging surveillance was performed for 159 (35.3%), more often for those with stage 1 (66.5%) than stage 0 (14.2%) tumours (p < 0.0001). Within the stage 1 group, 17 of the 47 patients (36.2%) treated by local (endoscopic or surgical transanal) resection alone were followed up by imaging monitoring. Factors significantly associated with surveillance in the entire cohort were the gastroenterologist assigned to the patient (p < 0.0001) and surgical vs endoscopic resection (OR = 39.0, p < 0.0001). The histological risk of lymph node metastasis was not significantly associated with imaging monitoring for stage 1 patients. Of the 5 patients who developed distant metastasis during follow-up, one was diagnosed through imaging surveillance. CONCLUSION: This study demonstrates excessive imaging surveillance for early-stage cancers. The use of surgical over endoscopic tumour resection could promote unnecessary surveillance.

Variations between endoscopists in rates of detection of colorectal neoplasia and their impact on a regional screening program based on colonoscopy after fecal occult blood testing.

BACKGROUND: There are few data about the performance variability among endoscopists participating to nationwide or regionwide colorectal cancer screening programs. OBJECTIVE: To assess the variability of neoplasia detection rates among endoscopists participating in a regional colorectal cancer screening program based on colonoscopy after biennial fecal occult blood testing (FOBT). DESIGN: Two rounds of colonoscopy were performed: round 1 took place in 2003 and 2004, and round 2 took place in 2005 and 2006. Secondary analysis of colonoscopy findings from the first 2 rounds was performed by using data drawn from all endoscopists who performed more than 30 colonoscopies in each round. Detection rates were adjusted for patient age and sex, and logistic regression analyses were conducted including these 2 variables and round number (1 or 2). SETTING: District of Ille-et-Vilaine in Brittany (population >900,000) between 2003 and 2007. MAIN OUTCOME MEASUREMENTS: The per-endoscopist adjusted rates of colonoscopies with at least 1, 2, or 3 adenomas, 1 adenoma 10 mm or larger, or a cancer. RESULTS: Among the 18 endoscopists who performed 3462 colonoscopies, the adjusted detection rates were in the following ranges: at least 1 adenoma, 25.4% to 46.8%; 2 adenomas, 5.1% to 21.7%; 3 adenomas, 2.7% to 12.4%; 1 adenoma 10 mm or larger, 14.2% to 28.0%; and cancer, 6.3% to 16.4%. Multivariate analyses showed that the endoscopist was not an independent predictor of cancer detection, but was an independent predictor of detecting adenomas, regardless of category; the R(2) of the models ranged from 6% to 13% only. LIMITATIONS: Other factors known to influence colorectal neoplasia occurrence and withdrawal time could not be taken into account. CONCLUSIONS: In a screening program with a high compliance rate with colonoscopy after FOBT, interendoscopist variability had no effect on cancer detection, but did influence identification of adenomas. The clinical impact of such findings merits further evaluation.

Yield of high-grade dysplasia based on polyp size detected at colonoscopy: a series of 2295 examinations following a positive fecal occult blood test in a population-based study.

PURPOSE: The aim was to determine the rate of high-grade dysplasia among patients with all adenomas, and its prevalence in patients with adenomas of different sizes in a well-defined population-based study. POPULATION AND METHODS: We performed a secondary analysis of the 2295 colonoscopies performed following a positive fecal occult blood test result during the first round of colorectal cancer screening in one French district. The rates of high-grade dysplasia were calculated for 3 size categories of adenoma (diminutive, or=10 mm). Predictive factors for high-grade dysplasia were assessed by univariate and multivariate analyses. RESULTS: A total of 1284 adenomas were detected in 784 subjects. High-grade dysplasia was present in 32.1% of the 784 subjects and in 2.7%, 16.0%, and 51.1% of those whose adenomas were diminutive, small, and large, respectively. Among subjects with no more than 2 small adenomas, the proportion of those with high-grade dysplasia was 12.4%. Both adenoma size and a villous component within adenomas were found to be independent predictive factors for high-grade dysplasia by multivariate analysis. CONCLUSIONS: Because of the high rate of high-grade dysplasia among small adenomas, our results reinforce the need to remove all small adenomas detected at colonoscopy. Furthermore, the results suggest that opting for CT colonography surveillance instead of colonoscopic removal among subjects with one or 2 small polyps revealed by CT colonography would have led to missed high-grade dysplasia in 12.4% of them.

Management of T1 colorectal cancers detected at screening colonoscopy: A study from the French national screening programme.

AIM: The main aim of this study was to examine the management strategies that were used and to determine the outcomes (survival and recurrence rate) of screen-detected T1-CRC. METHODS: Medical records from 207 patients with T1-CRC diagnosed through the French national screening programme in one district from 2003 to 2015 were analysed. The 5-year overall, CRC-specific and CRC-free survival were calculated for the whole cohort and for the 3 groups treated by endoscopic resection (ER) alone, ER followed by subsequent surgery (ERSS), and primary surgery (PS). RESULTS: Of the 207 patients, 81 (39%) underwent PS, and 126 (61%) underwent primary ER, of whom 82 (64%) underwent subsequent surgery. The 5-year overall and cancer-specific survival rates were 95.5% (95% CI, 90.8; 97.9) and 98.8% (95% CI, 95.4; 99.7%), respectively. Long-term cancer-specific mortality and recurrence crude rates were 2.4% and 5.6%, respectively. The 5-year CRC-free survival rate was 96.1% (95% CI, 91.8; 98.1%) and did not differ amongst the 3 groups (ER alone, ERSS and PS). CONCLUSION: This study demonstrates the good prognosis of screen-detected T1-CRC, regardless of the treatment strategy used. But, there is a room to improve the screening programme quality with regard to the management of screen-detected CRC.

Switching from guaiac to immunochemical faecal occult blood test increases participation and diagnostic yield of colorectal cancer screening.

BACKGROUND: Compared with the guaiac-faecal occult blood test (gFOBT), faecal immunological tests (FIT) are considered to be more effective for colorectal cancer (CRC) screening. However, only scarce research has examined the outcomes of switching to FIT within a mature gFOBT-based CRC screening programme. METHODS: We reported a 15-year experience of biennial FOBT screening in a well-defined population of approximately one million inhabitants, including six gFOBT-based screening rounds and one round with FIT at the 30 µg Hb/g cut-off. The main outcome measures were screening participation, FOBT positivity and advanced neoplasia detection in each round. RESULTS: In this study, 647 676 screenings were performed in 228 716 different individuals, leading to 17 819 positives and 16 580 follow-up colonoscopies. Compared with the last gFOBT round, switching to FIT led to an increased participation of nearly 20% points, and a fivefold increased detection of CRC and advanced adenoma among invitees (3-fold among attendees). The numbers needed to screen and scope to detect one advanced neoplasia declined from 221 to 66 and from 4.7 to 2.6, respectively. CONCLUSIONS: The present population-based study demonstrated a dramatical increase in the diagnostic yield of advanced neoplasia by switching to FIT within a mature gFOBT-based CRC screening programme.

Results of a 12-month quality-circle prescribing improvement programme for GPs.

BACKGROUND: The impact of a quality-circle GP prescribing improvement programme, implemented in France in 2001-2002, was assessed by a controlled study. The study involved all 27 GPs of three semi-rural areas of Brittany, France. Practice data (overall prescribing cost and markers of prescribing efficiency) were collated in an intention-to-treat analysis, using the Mann-Whitney U test. Twenty-four GPs attended the meetings regularly. The reduction in drug expenditure exceeded the cost of the programme, although variations in size effects were observed among the settings.

Additional mailing phase for FIT after a medical offer phase: The best way to improve compliance with colorectal cancer screening in France.

BACKGROUND: Compliance with colorectal cancer screening is critical to its effectiveness. The organisation of the mass screening programme in France has recently been modified with no evaluation of the consequences. AIMS: To evaluate the impact of the way the screening test is delivered on compliance. PATIENTS AND METHODS: During the first six months of the screening campaign (Ille-Vilaine, Brittany), general practitioners were asked to propose a faecal immunochemical test (FIT), OC-Sensor, to individuals at average risk for colorectal cancer (n=152,097). A subset of non-participants in the medical phase (n=13,071) was randomly chosen to receive a reminder that included the screening test or a simple postal reminder without the screening test. RESULTS: Compliance was 31% if the screening test was proposed during a medical consultation. In non-participants during the medical phase, it was 45% in those receiving both a reminder and the screening test and 28% amongst those receiving a simple reminder. An estimated overall participation rate of 54% can be expected if non-participants in the medical phase are sent a reminder together with the screening test. CONCLUSION: In France, a compliance rate above the minimum uptake rate of 45% recommended by European Union experts can be achieved if the FIT is mailed to non-participants after the medical free-offer phase.

Fecal immunological blood test is more appealing than the guaiac-based test for colorectal cancer screening.

BACKGROUND: The reasons for participation in fecal immunological testing (FIT) of subjects who were previously non-respondents to guaiac fecal occult blood testing (g-FOBT) have not been assessed. POPULATION AND METHODS: We aimed to determine the reasons for current compliance with FIT among non-responders to g-FOBT, termed "converts‿, in a French district. A questionnaire was returned by 170 converts aged from 55 to 75 years (response rate 75.2% after exclusions). RESULTS: The major barriers to participation in screening with g-FOBT were test-related: the test was perceived as complicated (24%) and it required three consecutive stools (28%). Among the test-related major determinants of FIT compliance was the perception that the test was less complicated than previous test (30%) and that a unique stool sample was required (29%). Among the non-test related major determinants of FIT compliance were the perception that the general practitioner was more convincing (31%) and the feeling to be more concerned because of age (21%). The reasons for compliance among converts did not differ according to age, sex, and rural or urban residence. CONCLUSIONS: Our study demonstrated that the simplicity of FIT and the endorsement of practitioners were both major motivations for FIT compliance among non-respondents in at least two previous consecutive campaigns.

Interendoscopist variability in proximal colon polyp detection is twice higher for serrated polyps than adenomas.

AIM: To assess the interendoscopist variability in the detection of colorectal polyps according to their location and histological type. METHODS: This study was a retrospective analysis of prospectively collected data from a regional colorectal cancer (CRC) screening program; 2979 complete colonoscopies from 18 endoscopists were included. Variability in performance between endoscopists for detection of at least one adenoma (A), one proximal adenoma (PA), one distal adenoma (DA), and one proximal serrated polyp (PSP) was assessed by using multilevel logistic regression models. RESULTS: The observed detection rates among the 18 endoscopists ranged from 24.6% to 47.6% (mean = 35.7%) for A, from 19.1% to 39.0% (mean = 29.4%) for DA, from 6.0% to 22.9% (mean = 12.4%) for PA, and from 1.3% to 19.3% (mean = 6.9%) for PSP. After adjusting for patient-level variables (sex, age), the interendoscopist detection rates variability achieved a significant level for A, PA, and PSP but not for DA (P = 0.03, P = 0.02, P = 0.02 and P = 0.08, respectively). This heterogeneity, as measured by the variance partition coefficient, was approximately threefold higher for PA (6.6%) compared with A (2.1%), and twofold higher for PSP (12.3%) compared with PA. CONCLUSION: These results demonstrate significant interendoscopist variability for proximal polyp particularly for serrated polyps, but not for distal adenoma detection. These findings contribute to explain the decreased effectiveness of complete colonoscopies at preventing proximal CRCs and the need to carefully assess the proximal colon during scope procedure.

Frequency and efficacy of additional investigations following incomplete colonoscopies: A population-based analysis.

BACKGROUND: Limited data are available on the follow-up of patients with incomplete colonoscopy following positive faecal occult blood testing. Our study aimed to determine the proportion of and reasons for incomplete colonoscopies, the proportion of patients who completed colonic evaluations, the methods used and the subsequent findings. METHODS: A total of 9483 colonoscopies performed after positive testing in a colorectal cancer screening programme setting were included. The study was prospective for index colonoscopy findings and partly retrospective for follow-up. RESULTS: Overall 297 colonoscopies were incomplete (3.2%). A secondary colonic evaluation was deemed necessary in 245 patients, of which 126 underwent an additional examination (51.4%). Radiology was the primary method used for complete colonic evaluation, whereas a repeat colonoscopy was performed in only 6.4%; the examination was normal in 119 patients (94.4%). A mucosal high-grade neoplasia was removed in 1, and multiple (≥3) adenomas were removed in 2 patients. CONCLUSIONS: The present screening programme with biennial faecal occult blood testing revealed a high colonoscopy completion rate, a low rate of secondary colonic evaluation, infrequent use of colonoscopy for completion, and a low detection rate of significant neoplasia.

The mean number of adenomas per procedure should become the gold standard to measure the neoplasia yield of colonoscopy: a population-based cohort study.

BACKGROUND: Measuring adenoma detection is a priority in the quality improvement process for colonoscopy. Our aim was (1) to determine the most appropriate quality indicators to assess the neoplasia yield of colonoscopy and (2) to establish benchmark rates for the French colorectal cancer screening programme. METHODS: Retrospective study of all colonoscopies performed in average-risk asymptomatic people aged 50-74 years after a positive guaiac faecal occult blood test in eight administrative areas of the French population-based programme. RESULTS: We analysed 42,817 colonoscopies performed by 316 gastroenterologists. Endoscopists who had an adenoma detection rate around the benchmark of 35% had a mean number of adenomas per colonoscopy varying between 0.36 and 0.98. 13.9% of endoscopists had a mean number of adenomas above the benchmark of 0.6 and an adenoma detection rate below the benchmark of 35%, or inversely. Correlation was excellent between mean numbers of adenomas and polyps per colonoscopy (Pearson coefficient r=0.90, p<0.0001), better than correlation between mean number of adenomas and adenoma detection rate (r=0.84, p=0.01). CONCLUSION: The mean number of adenomas per procedure should become the gold standard to measure the neoplasia yield of colonoscopy. Benchmark could be established at 0.6 in the French programme.

The positive predictive value of guaiac faecal occult blood test in relation to the number of positive squares in two consecutive rounds of colorectal cancer screening.

The aim of this study was to define the positive predictive values of a positive guaiac faecal occult blood test according to the number of positive squares, in two consecutive rounds of colorectal cancer mass screening in a French region. A total of 4172 colonoscopies were analyzed. Sex, age, number of positive squares, and colonoscopic and histopathologic findings were studied. In the results obtained, 76.6% of positive tests were positive with one or two squares. The number of positive squares was not related to sex, age and rank of participation. The positive predictive value for cancers and adenomas increased significantly with age, sex (male) and number of positive squares from 6.6% (one to two squares) to 27.6% (five to six squares) and from 15.2% to 22.2%, respectively. Cancer was diagnosed 211 times (54.1%) and advanced neoplasia was diagnosed 696 times (65.3%) following positive tests with one to two squares. The TNM stage of cancer increased significantly with the number of positive squares: 85.8% of stages 0-1-2 for one to two positive squares and 66.3% for five to six positive squares (P<0.001). Multivariate analysis showed an increased risk of cancer and advanced neoplasia for male patients and aged persons. The number of positive squares significantly increased the risk of cancer (odds ratio=4.6 for five to six positive squares) and the risk of advanced neoplasia (odds ratio=2.9). Age, sex and number of positive squares were independent predictive factors of positive guaiac faecal occult blood test. The proportion of TNM stages 3-4 was significantly higher in those with five to six positive squares. Performing a complete colonoscopy in every individual having a positive test, especially aged men with a high number of positive squares, should be a priority in any screening programme.