Colorectal cancer screening programme: is the French faecal immunological test (FIT) threshold optimal?

BACKGROUND: In France, the colorectal cancer organised screening programme uses the faecal immunological test. A positive test ⩾30 µg Hb/g of stool leads to a colonoscopy for identification of potential colorectal lesions. Cut-off values vary from 20 to 47 µg Hb/g of stool in Western countries. We herein question this threshold's relevance in a French population and perform a retrospective observational study using the Parisian database between 1 April 2015 and 31 December 2018. METHODS: Rates of participation, numbers of positive faecal immunological test (FIT), detection rates and positive predictive values for advanced adenomas and/or colorectal cancer were determined. Mean positivity values for colorectal lesions were calculated. RESULTS: In our population, there were 4.1% positive tests and 67.6% colonoscopy results available with final reports. Positive predictive value for advanced adenomas and colorectal cancer were 30% [95% confidence interval (CI) 29.8-30.3] and 7.4% (95% CI 7.35-7.52), respectively. The mean positivity value for all positive tests in our population was 101.7 µg Hb/g of stool (95% CI 85-118.3). There were 1136 normal colonoscopies (21.4%) with a mean positivity value of 88.6 µg Hb/g of stool. Following a negative test in a first screening campaign, 40.8% of patients in our population performed a second test with a positivity rate of 1.3% and with the encounter of 81 colorectal cancers. The risk of having a positive test during the second screening campaign and finding advanced colorectal lesions significantly increased (all p < 0.001) when comparing negative FIT results ranging between 15 and 29 µg Hb/g of stool to 0 and 14 µg Hb/g of stool from the previous campaign. CONCLUSION: Using the current positivity threshold, some patients were considered negative with a delay in colorectal cancer diagnosis, suggesting the threshold could be lowered. Also, the mean positivity value for normal colonoscopies was high, raising the question of upper gastrointestinal bleeding.

Results of the national organised colorectal cancer screening program with FIT in Paris.

In France, colorectal cancer (CRC) benefits from a nationwide screening program. The faecal immunochemical test (FIT) is being used since April 2015. The test is recommended in asymptomatic patients followed by a colonoscopy if positive for identification and treatment of colorectal lesions. We investigate the CRC national organised screening program using FIT in Paris. We performed a retrospective observational study, collecting data from the screening program in Paris using the ADECA75 database. Rates of participation, numbers of positive FIT, detection rates and positive predictive values (PPV) for advanced adenomas (AA) and/or CRC were determined. Between 01/01/2016 and 30/06/2017, 620.227 Parisians were eligible and 409.340 were invited to participate to the program. A total of 88.796 participants (23%) performed the test with 3.839 positive tests (4.3%). In the positive test population, 2.706 out of 3.839 individuals (70.5%) performed the required colonoscopy with available reports. Histology reports were only available for 2.401 participants (88,7%). Regarding lesions, 733 (30,5%) and 205 patients (8.5%) had AA and CRC, respectively. Over 18 months of screening with FIT in Paris, the PPV is in line with expected results while the participation rate is below European recommendations.

Impact of a Doctor's Invitation on Participation in Colorectal Cancer Screening: A Cluster Randomized Trial.

BACKGROUND: There is a need to improve participation in colorectal cancer screening. Our objective was to assess the impact of a signature from the patient's general practitioner on a letter inviting patients to participate in a colorectal cancer screening. METHOD: We conducted a cluster randomized controlled trial with 57 general practitioners established in Paris for more than 5 years, randomized to intervention or usual-care arms. There were 3422 patients included, ages 50-74 years, from general practitioner patient files, and eligible for an invitation letter or a reminder letter to participate in the national population-based screening program. In the intervention arm, patients received a standard letter signed by their general practitioner inviting them to visit the general practitioner's office for a fecal occult blood test if they were eligible. Control patients received the standard invitation letter or the standard reminder. All letters were sent by the district screening organization. The main outcome was the proportion of patients who took the fecal occult blood test within 6 months after the invitation. RESULTS: Among patients eligible for the study, 508 (14.8%) took a fecal occult blood test after being invited; 285 (15%; 95% confidence interval [CI], 13.5-16.7) in the intervention group and 223 (14.6%; 95% CI, 12.9-16.5) in the control group, with no statistical difference between the 2 groups (odds ratio 1.04; 95% CI, 0.83-1.31; P = .731). CONCLUSIONS: The addition of a general practitioner's signature to a standard letter inviting patients to take a fecal occult blood test had no impact on the frequency of patients taking the fecal occult blood test in the Paris program of colorectal cancer screening.

Quality indicators for colonoscopy procedures: a prospective multicentre method for endoscopy units.

BACKGROUND AND AIMS: Healthcare professionals are required to conduct quality control of endoscopy procedures, and yet there is no standardised method for assessing quality. The topic of the present study was to validate the applicability of the procedure in daily practice, giving physicians the ability to define areas for continuous quality improvement. METHODS: In ten endoscopy units in France, 200 patients per centre undergoing colonoscopy were enrolled in the study. An evaluation was carried out based on a prospectively developed checklist of 10 quality-control indicators including five dependent upon and five independent of the colonoscopy procedure. RESULTS: Of the 2000 procedures, 30% were done at general hospitals, 20% at university hospitals, and 50% in private practices. The colonoscopies were carried out for a valid indication for 95.9% (range 92.5-100). Colon preparation was insufficient in 3.7% (range 1-10.5). Colonoscopies were successful in 95.3% (range 81-99). Adenoma detection rate was 0.31 (range 0.17-0.45) in successful colonoscopies. CONCLUSION: This tool for evaluating the quality of colonoscopy procedures in healthcare units is based on standard endoscopy and patient criteria. It is an easy and feasible procedure giving the ability to detect suboptimal practice and differences between endoscopy-units. It will enable individual units to assess the quality of their colonoscopy techniques.

Prevention by daily soluble aspirin of colorectal adenoma recurrence: 4-year results of the APACC randomised trial.

BACKGROUND: Aspirin inhibits colorectal carcinogenesis. In a randomised double-blind placebo-controlled trial, daily soluble aspirin significantly reduced recurrence of colorectal adenomas at 1-year follow-up. In this study the results of daily intake of low-dose aspirin on polyp recurrence at 4-year follow-up are presented. METHODS: 272 patients (naive for chronic aspirin use) with colorectal adenomas were randomly assigned to treatment with lysine acetylsalicylate 160 mg/day (n=73) or 300 mg/day (n=67) or placebo (n=132) for 4 years. The primary endpoints were adenoma recurrence and adenomatous polyp burden at year 4, comparing aspirin at either dose with placebo. The same endpoints were also assessed at year 1 or 4 (last colonoscopy performed for each patient). RESULTS: At the final year 4 colonoscopy the analysis included 185 patients (55 receiving aspirin 160 mg/day, 47 aspirin 300 mg/day and 83 placebo). There was no difference in the proportion of patients with at least one recurrent adenoma between patients receiving aspirin at either dose and those treated with placebo (42/102 (41%) vs 33/83 (40%); NS) or in the adenomatous polyp burden (3.1 ± 5.8 mm vs 3.4 ± 6.2 mm; NS). Also, the proportion of patients with at least one advanced recurrent adenoma did not differ (10/102 [corrected] (10%) in the aspirin group vs 7/83 (8.4%) [corrected] in the placebo group; NS). CONCLUSION: Daily low-dose aspirin decreased adenoma recurrence significantly at 1 year but not at year 4. This discrepancy might be explained by a differential effect of aspirin according to the natural history of the polyp. TRIAL REGISTRATION NUMBER: NCT 00224679.

Cyclooxygenase-2 expression and recurrence of colorectal adenomas: effect of aspirin chemoprevention.

BACKGROUND: Low-dose aspirin reduces the incidence of colorectal cancer and recurrence of adenomas. Cyclooxygenase-2 (COX-2), one of its main target enzymes, is reportedly over-expressed in colorectal adenomas. AIM: To assess COX-2 expression, in relation to adenoma recurrence and the protective effect of aspirin, in a large series of colorectal adenomas, recruited from a double-blind randomised controlled trial comparing recurrences after low-dose aspirin or placebo. METHODS: Follow-up colonoscopies were performed after 1 and 4 years to assess adenoma recurrence. COX-2 expression was assessed by immunohistochemistry for each adenoma obtained at baseline colonoscopy, separately for epithelium, deep stroma and overall. Architecture, grade of dysplasia, K-ras mutation, p53 and cyclin D1 expression were studied. RESULTS: COX-2 expression could be assessed in 219 adenomas from 136 PATIENTS: 128 adenomas (58%) from 59 patients strongly expressed COX-2. Strong COX-2 expression predominated in adenomas larger than 10 mm (84/129 vs 44/90; p=0.02) and in adenomas showing high-grade dysplasia (22/29 vs 104/188; p=0.04). Deep stromal but not epithelial initial expression of COX-2 predicted adenoma recurrence in the whole population (30/72 patients or 42% strongly expressed deep stromal COX-2 compared with 16/64 or 25% without recurrent adenoma; p=0.04). The protective effect of aspirin was mainly observed in patients in whom COX-2 initial expression was low (RR for recurrence in patients taking aspirin with low COX-2 expression: 0.59; 95% CI 0.39 to 0.90; p=0.02). There was no significant effect of aspirin at the end of the trial. CONCLUSION: Over-expression of COX-2 was frequent and predominated in large and high-grade dysplasia adenomas. Deep stromal but not epithelial initial expression of COX-2 predicted recurrence of adenomas. Aspirin did not act preferentially on patients whose initial adenomas strongly expressed COX-2.

Daily soluble aspirin and prevention of colorectal adenoma recurrence: one-year results of the APACC trial.

BACKGROUND & AIMS: Epidemiologic and experimental studies have suggested that aspirin intake reduces the risk for colorectal carcinogenesis. However, the available data are not sufficient to serve as the basis for firm recommendations. METHODS: We randomly assigned 272 patients with a history of colorectal adenomas (at least one more than 5 mm in diameter, or more than 3) to daily lysine acetylsalicylate (160 or 300 mg/day) or placebo for 4 years. The primary end points were adenoma recurrence after 1 and 4 years. These results are those of the year 1 colonoscopy. RESULTS: Among the 238 patients who completed the year 1 colonoscopy, at least one adenoma was observed in 38 patients of the 126 (30%) in the aspirin group and in 46 of the 112 (41%) in the placebo group; relative risk was 0.73 (95% confidence interval [CI]: 0.52-1.04; P = 0.08). At least one adenoma of more than 5 mm diameter was observed in 13 patients (10%) in the aspirin group and 26 (23%) in the placebo group (P = 0.01). The corresponding numbers for adenomas more than 10 mm in diameter were one (1%) and 7 (6%) (P = 0.05). Stepwise regression showed that independent factors associated with lower adenoma recurrence are aspirin treatment (adenoma >5 mm, P = 0.01), absence of personal history of adenoma before the entry colonoscopy (P = 0.01), and initial adenomatous polyp burden less than 10 mm (P = 0.001). CONCLUSIONS: Daily soluble aspirin is associated with a reduction in the risk for recurrent adenomas found at colonoscopy 1 year after starting treatment.

[Inter-observer agreement on histological diagnosis of colorectal polyps: the APACC study]. / Reproductibilité inter-observateurs du diagnostic anatomo-pathologique des polypes colorectaux.

INTRODUCTION: Adenomas are considered as precursors of colorectal adenocarcinomas. After polypectomy, surveillance depends on the histological analysis of the excised polyps. The aim of the study was to evaluate the reproducibility of the histological diagnosis performed by pathologists from participating centers in the APACC study. Their interpretations were compared to those of the study's consensual diagnosis performed by two reference pathologists. METHODS: The agreement proportion and the concordance coefficient (kappa) were estimated for 326 polyps obtained from the first 148 patients included. RESULTS: A concordant diagnosis for the adenomatous nature was shown for 246 of the 255 adenomas (96%). The diagnosis of both the histological type and the degree of dysplasia was concordant for only 92 of the 255 adenomas (36%). Kappa values were 0.67 for the adenomatous nature, 0.46 for the histological types, and 0.26 for the degree of dysplasia. CONCLUSION: A high degree of agreement was obtained for the diagnosis of the adenomatous nature. By contrast, high variations were observed for the interpretations of the histological type and the degree of dysplasia.