[Colorectal cancer screening program : Test completion rate and follow-up results after selective mailing of the test kit, based on likelihood of participation]

BACKGROUND

Even though theinterest of a Colorectal-Cancer Screening Program has been amply demonstrated, in French departments the participation rate (PR) seldom reaches 45%. In the absence of mass mailing, a strategy (S-1) consisting in mailing a test kit to people having made a request was implemented in 2015. In 2017, another mailing strategy (S-2), which consisted in sending the test kit only to people likely to take the test, was programmed. This study assesses the respective impact of these two strategies as compared to the standard approach (S-0).

METHODS

The study included 254,113 (S-0), 4,130 (S-1) and 10,887 (S-2) people aged 50-74, targeted during the 2016-2017 campaign in Seine-Saint-Denis (France). S-0 persons received a 2nd reminder without a test-kit, while S-1 persons received, at their request, a mailed test kit. Without having made a request, S-2 persons the mailed test kit according to probability of participation (Proba) which was estimated a priori by the ratio between the sum total of index values (frequency of previous participation, date of most recent participation, age) and a theoretical maximum. Completion rates (test/colonoscopy) were compared 18 months after the last S-2 kit was sent.

RESULTS

PR was highest in S-1 (S-0: 5.8%, S-1: 74.9%, S-2: 31.3%; p < 0.0001). In S-2, PR rose as Proba increased (Proba: ]0-30%], ]30-50%], ]50-75%], ]75-100%]; PR: 21.1%, 23.3%, 36.2%, 52.8% respectively; p < 0.05). Compared to the ≥70 years age-group, the 50-54 years age-group presented a lower PR in S-1 (65.9% vs. 85.1%; p < 0.05) whereas it presented a higher PR in S-0 (4.3% vs. 7.1%; p < 0.05) and in S-2 (23.2% vs. 54.5%; p < 0.05). All in all, colonoscopy completion rates were highest in S-1 (S-0: 62.2%, S-1: 80.0%, S-2: 65.0%; p < 0.001).

CONCLUSION

Test-kit mailing without spontaneous request does not lead to an optimal level of participation, thereby highlighting a need to give thought to new and improved mobilization methods. The relatively pronounced participation of younger persons, who are not favored by present-day testing specifications, underscores the interest of a specific approach addressed to active people, who are less inclined than elderly individuals to regularly consult their attending physicians.

Feasibility of encouraging participation in colorectal cancer screening campaigns by motivating people through the social network, Facebook

AIM

To describe the results of a feasibility phase and the expected results of a new approach to increase the participation rate in a Colorectal Cancer Organized Screening Program (CRCSP) through Facebook awareness messages.

METHOD

This approach targets people aged 50-74 years, who reside in an urban deprived area and regularly connect to Facebook. The feasibility phase ran over 2 months (December 2018 and January 2019) in six municipalities (Seine-Saint-Denis, France). The full provisional campaign will run over a year. The approach consists of sending electronic awareness messages on the importance of screening for colorectal cancer using a specific Facebook module. Subjects who consent to screening complete a test-kit application form. The eligibility of each subject to participate in screening is determined by a doctor before the kit is sent out.

RESULTS

A total of 39 900 people were reached by the feasibility phase campaign, and 9200 were able to watch at least one Facebook message/video. Of those, 4450 people logged to learn more about the CRCSP, 298 applied for a test kit, 160 test kit applicants were eligible to participate and the test completion rate was 41.9%. According to these feasibility results, 366 120 targeted people would connect regularly in the tested area, 141 541 of whom would be interested in a specific promotional message posted on Facebook. Requests could be made for 9770 kits, with 5246 people being eligible to participate in screening. The expected test-completion rate is estimated at 42%-89%. This would represent 5%-11% of the tests carried out in the area during the same period by 'classical' CRCSP.

CONCLUSION

Implementation of the Facebook strategy would significantly improve the rate of participation in the CRCSP by mobilizing people with no previous participation, including younger subjects.

Cost-effectiveness analysis of alternative colon cancer screening strategies in the context of the French national screening program

BACKGROUND

A nationwide colorectal cancer (CRC) screening program was set up in France from 2009 for average-risk, asymptomatic people aged 50-74 years based on an immunochemical fecal occult blood test [faecal immunochemical test (FIT)] every 2 years, followed by colonoscopy if positive. The European standard recommends a participation rate of 45% for the program to be cost-effective, yet the latest published rate in France was 34%. The objective of this study was to compare the cost effectiveness of screening alternatives taking real-world participation rates into account.

METHODS

Eight screening strategies were compared, based either on a screening test (Guaiac or FIT testing, blood-based, stool DNA, computed tomography colonography, colon capsules, and sigmoidoscopy) followed by full colonoscopy if positive or direct colonoscopy. A microsimulation model was used to estimate the cost effectiveness associated with each strategy.

RESULTS

Compared with no screening, FIT was associated with a 14.0 quality-adjusted life year (QALY) increase of €50,520 per 1000 individuals, giving an incremental cost-effectiveness ratio (ICER) of €3600/QALY. Only stool DNA and blood-based testing were associated with a QALY increase compared with FIT, with stool DNA weakly dominated by blood-based testing, and the latter associated with an ICER of €154,600/QALY compared with FIT. All other strategies were dominated by FIT.

CONCLUSION

FIT every 2 years appears to be the most cost-effective CRC screening strategy when taking into account a real-world participation rate of 34%.

Oesophageal involvement in 26 consecutive patients with mucous membrane pemphigoid

BACKGROUND

Oesophageal involvement of mucous membrane pemphigoid (MMP) has not yet been thoroughly described.

OBJECTIVES

To characterize systematically the endoscopic lesions of a series of patients with oesophageal symptoms seen at a referral centre for autoimmune bullous diseases.

METHODS

Clinical, endoscopic and immunological findings of consecutively referred patients with MMP with oesophageal involvement, systemic and endoscopic treatments, and follow-up are described.

RESULTS

Of 477 consecutive patients with MMP consulting between 2002 and 2012, 26 (5·4%) had symptomatic oesophageal involvement. Dysphagia, observed in 23 (88%) patients, was the most frequent symptom. Oesophageal symptoms could be the first sign of MMP. Patients with oesophageal involvement had a mean of three other involved sites. At initial oesophageal endoscopy, 17 of 26 patients had active lesions (intact bullae, erosions and/or erythema), 15 had stricture(s) and 12 had other cicatricial lesions. Systemic therapy alone achieved oesophageal symptom relief for five patients. Dilatation was combined with systemic therapy for 12 patients and was successful in nine; one perforation occurred.

CONCLUSIONS

Symptomatic oesophageal involvement affected 5·4% of patients with MMP. Dermatologists and gastroenterologists should be aware of these mucocutaneous diseases and their oesophageal involvement, as it could lead to earlier diagnosis and better care. Oesophageal dilatation could be a therapeutic option for symptomatic stricture not relieved by optimized systemic therapy alone.

Is-it possible to distinguish irritable bowel syndrome with constipation from functional constipation?

BACKGROUND

The Rome III criteria classify patients complaining of constipation into two main groups: patients with functional constipation (FC) and patients with constipation predominant irritable bowel syndrome (IBS-C). The purpose of this study was to identify differences in the intensity of symptoms and total and segmental colonic transit time in these two types of patients.

METHODS

We performed a prospective evaluation of 337 outpatients consecutively referred for chronic constipation and classified according to the Rome III criteria as FC or IBS-C. They were asked to report symptom intensity, on a 10-point Likert scale, for diarrhea, constipation, bloating and abdominal pain. Stool form was reported using the Bristol scale, and colonic transit time was measured by using multiple-ingestion single-marker single-film technique. Statistical analysis was completed by a discriminant analysis.

RESULTS

Female gender and obstructed defecation was more frequent in IBS-C patients than in FC patients. IBS-C patients reported greater symptom intensity than FC patients, but stool form, and total and segmental colonic transit time were not different between the two groups. Multivariate logistic regression showed that only two parameters, bloating and abdominal pain, were related to the IBS-C or to the FC phenotype, and discriminant analysis showed that these two parameters were sufficient to give a correct classification of 71% of the patients.

CONCLUSIONS

Our study suggests that self-evaluation of abdominal pain and bloating is more helpful than colonic transit time in classifying patient as IBS-C or FC.

Functional gastrointestinal disorders in 35,447 adults and their association with body mass index

BACKGROUND

Functional gastrointestinal disorders' (FGIDs) associations with body mass index (BMI) have not been thoroughly investigated in the general population.

AIM

To investigate the overlap between functional dyspepsia (FDy), irritable bowel syndrome (IBS), functional constipation (FC) and functional diarrhoea (FDh) and the relationship between BMI and those diagnoses in a large French adult population.

METHODS

Subjects participating in the Nutrinet-Santé cohort study completed a questionnaire based on Rome III criteria. Anthropometrics, socio-demographical and lifestyle data were collected via self-administered questionnaires. Associations between BMI and FGIDs were investigated with multivariate logistic regression.

RESULTS

A total of 35 447 subjects were included in the analysis. Among subjects with FGIDs, 10.4% presented more than one disorder. [FDy coexisted with IBS (23.6%) and FC (15.1%)]. Associations between BMI and FDy differed according to sex. In females, higher odds were observed for underweight and obesity subgroups (OR = 1.26 (95% CI: 0.99-1.59), OR = 1.35 (1.08-1.69), OR = 1.20 (0.81-1.77), OR = 1.47 (0.89-2.42) for underweight, class I, II and III obesity respectively compared with normal BMI), forming a U-shaped relationship confirmed with nonlinear model (P < 0.001). In females, FDh was associated with BMI [OR = 1.05 (1.03-1.07), P < 0.001]. In males, a negative association between BMI and IBS was observed [OR = 0.97 (0.94-0.99), P=0.04]. Other associations were not significant.

CONCLUSIONS

Our study showed an important overlap in FGIDs, supporting the contention of common pathophysiological mechanisms. Relationships between BMI and FGIDs appeared to be sex-dependent. Interaction by sex in the association between BMI and FGIDs should therefore be further explored.

Endogenous proteins in the ileal digesta of adult humans given casein-, enzyme-hydrolyzed casein- or crystalline amino-acid-based diets in an acute feeding study

BACKGROUND/OBJECTIVES

To ascertain if the form of dietary nitrogen (free amino acids (AA), small peptides, or intact protein) affects the endogenous nitrogen containing substances lost from the upper digestive tract of humans.

SUBJECTS/METHODS

Digesta were collected via a naso-ileal tube from the terminal ileum of 16 adult humans in a single parallel study following an acute feeding regimen. Subjects were given an iso-nitrogenous and isocaloric test meal containing 150 g of casein (CAS) (n=6), enzyme-hydrolyzed casein (HCAS) (n=5) or crystalline AA (n=5) dissolved in 550 ml of water, as the sole sources of nitrogen.

RESULTS

The mean concentrations and flows of total nitrogen, protein nitrogen, and soluble protein nitrogen passing the terminal ileum were significantly higher (P <0.01) for the CAS and HCAS test-meal groups compared to the AA meal group. Dietary CAS and HCAS had a considerable influence on digesta mucin concentrations and flows compared to free AA (+41%). Only 3-4% of the total nitrogen remained unidentified.

CONCLUSIONS

The form of dietary nitrogen (protein, small peptides or free AA) had an acute effect upon the secretion or reabsorption of endogenous proteins in the small intestine of healthy humans, as evident from significant differences in both the quantity and composition of the proteins found in digesta at the end of the ileum.

Abdominal pain localization is associated with non-diarrheic Rome III functional gastrointestinal disorders

BACKGROUND

Abdominal pain is common in patients with functional bowel disorders (FBDs). The aim of this study was to characterize the predominant sites of abdominal pain associated with FBD subtypes, as defined by the Rome III criteria.

METHODS

A total of 584 consecutive patients attending FBD consultations in a tertiary center participated in the study. Stool form, abdominal pain location (nine abdominal segments), and pain intensity (10-point Likert scale) during the previous week were recorded. Logistic regression analysis was used to characterize the association of abdominal pain sites with specific FBD subtypes.

KEY RESULTS

FBDs were associated with predominant pain sites. Irritable bowel syndrome (IBS) with constipation was associated with pain in the left flank and patients were less likely to report pain in the right hypochondrium. Patients with functional constipation reported pain in the right hypochondrium and were less likely to report pain in the left flank and left iliac site. IBS with alternating constipation and diarrhea was associated with pain in the right flank, and unsubtyped IBS with pain in the hypogastrium Patients with functional abdominal pain syndrome reported the lower right flank as predominant pain site. Patients with unspecified FBDs were least likely to report pain in the hypogastrium. Patients with functional diarrhea, IBS with diarrhea, or functional bloating did not report specific pain sites.

CONCLUSIONS & INFERENCES

The results from this study provide the basis for developing new criteria allowing for the identification of homogeneous groups of patients with non-diarrheic FBDs based on characteristic sites of pain.

Bowel preparation for colonoscopy: European Society of Gastrointestinal Endoscopy (ESGE) guideline

BACKGROUND AND AIM

This Guideline is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). It addresses the choice amongst regimens available for cleansing the colon in preparation for colonoscopy.

METHODS

This Guideline is based on a targeted literature search to evaluate the evidence supporting the use of bowel preparation for colonoscopy. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was adopted to define the strength of recommendation and the quality of evidence.

RESULTS

The main recommendations are as follows. (1) The ESGE recommends a low-fiber diet on the day preceding colonoscopy (weak recommendation, moderate quality evidence). (2) The ESGE recommends a split regimen of 4 L of polyethylene glycol (PEG) solution (or a same-day regimen in the case of afternoon colonoscopy) for routine bowel preparation. A split regimen (or same-day regimen in the case of afternoon colonoscopy) of 2 L PEG plus ascorbate or of sodium picosulphate plus magnesium citrate may be valid alternatives, in particular for elective outpatient colonoscopy (strong recommendation, high quality evidence). In patients with renal failure, PEG is the only recommended bowel preparation. The delay between the last dose of bowel preparation and colonoscopy should be minimized and no longer than 4 hours (strong recommendation, moderate quality evidence). (3) The ESGE advises against the routine use of sodium phosphate for bowel preparation because of safety concerns (strong recommendation, low quality evidence).

Long-acting somatostatin analogues decrease blood transfusion requirements in patients with refractory gastrointestinal bleeding associated with angiodysplasia

BACKGROUND

Gastrointestinal angiodysplasias (GIADs) may be the cause of recurrent bleeding, despite endoscopic treatment.

AIM

To evaluate the effect of long-acting somatostatin analogues on blood transfusion requirements, in patients with refractory bleeding due to GIADs.

METHODS

Consecutive patients with recurrent bleeding from GIADs were enrolled. They received somatostatin analogue treatment for at least 6 months. The efficacy was evaluated in terms of blood transfusions, frequency of bleeding episodes and haemoglobin level during 6 months of treatment (Period During) compared to a 6-months' period before treatment (Period Before).

RESULTS

Fifteen patients were enrolled from 2007 to 2010. The median duration of somatostatin analogue treatment was 12 months (range: 6-36). The number of transfusions significantly decreased in Period During compared with Period Before [median number: 2 (0-14) vs. 10 (6-24); P < 0.001]. The percentage of patients who experienced a bleeding event was lower during somatostatin analogues treatment (20% vs. 73%; P = 0.01). The mean haemoglobin level was significantly higher when somatostatin analogues were offered [median: 10 g/dL (9-13) vs. 7 (5-8.5); P < 0.001]. None of the patients discontinued treatment due to side effects.

CONCLUSIONS

Long-acting somatostatin analogues treatment decreased transfusion needs in patients with refractory bleeding from gastrointestinal angiodysplasias. Bleeding episodes were limited and haemoglobin improved during treatment. Long-acting somatostatin analogues may represent an option for the management of patients with chronic bleeding due to gastrointestinal angiodysplasias.

Colon capsule endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

PillCam colon capsule endoscopy (CCE) is an innovative noninvasive, and painless ingestible capsule technique that allows exploration of the colon without the need for sedation and gas insufflation. Although it is already available in European and other countries, the clinical indications for CCE as well as the reporting and work-up of detected findings have not yet been standardized. The aim of this evidence-based and consensus-based guideline, commissioned by the European Society of Gastrointestinal Endoscopy (ESGE) is to furnish healthcare providers with a comprehensive framework for potential implementation of this technique in a clinical setting.

Endoscopist-directed propofol administration versus anesthesiologist assistance for colorectal cancer screening: a cost-effectiveness analysis

BACKGROUND

Propofol for colonoscopy is largely administered by anesthesiologists or anesthesiology nurses in the United States (US) and Europe. Endoscopist-directed administration of propofol (EDP) by nonanesthesiologists has recently been proposed, with potential savings of anesthetist reimbursement costs. We aimed to assess potential EDP-related benefit in a screening setting.

METHODS

In a Markov model the total number of screening and follow-up colonoscopies in a cohort of 100 000 US subjects were estimated. Anesthetist-assisted colonoscopy was compared with an EDP strategy. Model outputs were projected onto the 50 - 80-year-old US population, assuming 27 % as the current uptake for colonoscopy screening. Anesthetist costs were estimated using the mean reimbursement for the corresponding Medicare code (≥ 65-year-olds) and from commercial insurance information (50 - 64-year-olds). The proportion of colonoscopies with anesthesiologist assistance was estimated from the Medicare database. Mean nurse salary was used to estimate the cost of a 2-week EDP training. The absolute number of US endoscopists was estimated by inflating by 33 % the number of board-certified gastroenterologists. No EDP mortality was assumed in the reference scenario, and 0.0008 % mortality in the sensitivity analysis. US census data were adopted. Analogous inputs were used for France to assess EDP-related benefit in a European country.

RESULTS

EDP training for 17 166 nurses (one for each US endoscopist) showed a cost of $ 47 million. Cost estimates for anesthesiologist assistance for colonoscopy were $ 95 (Medicare) and $ 450 (non-Medicare commercial insurance), with 34.8 % of colonoscopies requiring anesthesiologist assistance. US implementation of an EDP policy showed a 10-year saving of $ 3.2 billion (Monte Carlo analysis 5 - 95 % percentiles $ 2.7 - $ 11.9 billion). In the sensitivity analysis, assuming 50 % of colonoscopies were anesthetist-assisted showed an EDP benefit of $ 4.6 billion. Assuming a 0.0008 % mortality rate, the incremental cost - effectiveness of anesthetist-assisted colonoscopy versus an EDP policy was $ 1.5 million per life-year gained, supporting EDP as the optimal choice. A 31-fold increase of EDP-related mortality or a 17-fold cost reduction for anesthetist-assisted colonoscopy was required for EDP to become not cost-effective in this scenario. Implementation of an EDP policy in France, within a guaiac-fecal occult blood test (g-FOBT) screening program, was estimated to save € 0.8 billion in 10 years.

CONCLUSIONS

The absolute economic benefit of EDP implementation in a screening setting is probably substantial with 10-year savings of $3.2 billion in the US and €0.8 billion in France. The impact of an eventual EDP-related mortality on EDP cost - effectiveness seems marginal. The huge economic and medical resources entailed by anesthetist-assisted colonoscopy could be more efficiently invested in other clinical fields.

Wireless pH capsule--yield in clinical practice

Wireless pH monitoring is one of the recent technologies that focus on improving the diagnosis of gastroesophageal reflux disease (GERD). The capsule, which is fixed within the esophagus, transmits data via telemetry to an external receiver. The capsule is usually inserted 6 cm above the squamocolumnar junction during an upper endoscopy. The standard recording duration is 48 hours but this can be extended to 96 hours. The wireless capsule has been shown to be at least as accurate as the conventional catheter for the monitoring of esophageal pH. Normal pH values have been established in three different series. The use of a wireless capsule provides an increased diagnostic yield for GERD compared with the conventional catheter. The increased yield is the result of higher sensitivity to detect both abnormal acid esophageal exposure and positive symptom-reflux association. This may be related both to the prolonged recording duration and to fewer dietary modifications and restrictions on activities. Several studies have shown that the pH capsule was better tolerated by patients than the conventional pH catheter. Mild-to-moderate chest pain represents the main side effect of the pH capsule: severe chest pain requiring endoscopic removal of the capsule is rare. The main indication for wireless capsule application is monitoring of distal esophageal pH for diagnostic purpose, particularly in patients with a normal endoscopic examination. The capsule technique has some limitations: costs are higher than conventional pH monitoring, misplacement may occur, and the sampling rate is lower. Finally, compared with pH-impedance monitoring, only acid reflux events can be evaluated.

Cost effectiveness and projected national impact of colorectal cancer screening in France

BACKGROUND

Colorectal cancer (CRC) is a major cause of morbidity and mortality in France. Only scanty data on cost-effectiveness of CRC screening in Europe are available, generating uncertainty over its efficiency. Although immunochemical fecal tests (FIT) and guaiac-based fecal occult blood tests (g-FOBT) have been shown to be cost-effective in France, cost-effectiveness of endoscopic screening has not yet been addressed.

METHODS

Cost-effectiveness of screening strategies using colonoscopy, flexible sigmoidoscopy, second-generation colon capsule endoscopy (CCE), FIT and g-FOBT were compared using a Markov model. A 40 % adherence rate was assumed for all strategies. Colonoscopy costs included anesthesiologist assistance. Incremental cost-effectiveness ratios (ICERs) were calculated. Probabilistic and value-of-information analyses were used to estimate the expected benefit of future research. A third-payer perspective was adopted.

RESULTS

In the reference case analysis, FIT repeated every year was the most cost-effective strategy, with an ICER of €48165 per life-year gained vs. FIT every 2 years, which was the next most cost-effective strategy. Although CCE every 5 years was as effective as FIT 1-year, it was not a cost-effective alternative. Colonoscopy repeated every 10 years was substantially more costly, and slightly less effective than FIT 1-year. When projecting the model outputs onto the French population, the least (g-FOBT 2-years) and most (FIT 1-year) effective strategies reduced the absolute number of annual CRC deaths from 16037 to 12916 and 11217, respectively, resulting in an annual additional cost of €26 million and €347 million, respectively. Probabilistic sensitivity analysis demonstrated that FIT 1-year was the optimal choice in 20% of the simulated scenarios, whereas sigmoidoscopy 5-years, colonoscopy, and FIT 2-years were the optimal choices in 40%, 26%, and 14%, respectively.

CONCLUSIONS

A screening program based on FIT 1-year appeared to be the most cost-effective approach for CRC screening in France. However, a substantial uncertainty over this choice is still present.

Endoscopic findings in Cowden syndrome

Cowden syndrome is characterized by diffuse hamartomas involving the whole digestive tract. The gastrointestinal expression of the disease is inconstant, but hamartomatous polyposes are frequent. In a multicenter study we studied the endoscopic appearance of Cowden syndrome--as defined by fulfillment of international consortium criteria--in 10 patients. In 6 of the 10 patients the connection with Cowden syndrome was made retrospectively on the basis of the gastrointestinal endoscopic findings. All patients had upper and lower gastrointestinal tract involvement. Mean follow-up duration was 9.5 years (range: 2-26 years). Mean age was 37 years (range: 18-56 years). Polyps of the upper gastrointestinal tract were hamartomas, ganglioneuromas, lipomas, and adenomas. Diffuse glycogenic acanthosis was reported in nine patients. Besides the classical hamartomatous polyposis, diffuse macroscopic esophageal acanthosis and microscopic ganglioneuromatosis are other key findings associated with a diagnosis of Cowden syndrome. Physicians should be aware of these characteristics in order to diagnose Cowden syndrome early.

Non-compliance does not impair qualitative evaluation of colonic transit time

BACKGROUND

Measurement of colonic transit time (CTT) by using radiopaque markers with the "Multiple ingestion-Single film" technique is a simple, reproducible technique to measure total and segmental CTT. However, it requires good compliance of the patients, who must ingest the capsules containing radio-opaque markers for 6 consecutive days. The purpose of this study was to estimate the error in CTT measurement if they fail to do this.

METHODS

The protocol tested was to ingest 12 markers per day during 6 days and take a plain film of the abdomen on day 7. The study was done by simulation using a 3-compartiment model (right colon, left colon, rectosigmoid area). There was a set of 67,525 possibilities with possible single or double failure of markers ingestion for 6 days either 238,266 combinations for one omission, or 312,375 combinations for two omissions; the absence of omission was the reference. The analysis focused on two complementary aspects of the evaluation of omission: quantitatively, the absolute and relative error on the CTT measured and qualitatively, the diagnostic error (a delayed transit is defined by a total CTT > 65 hours).

KEY RESULTS

Total and segmental CTT measured when omission occurred were greater than the reference time. The difference is particularly important, when omission occurs early during the study for all segments. Qualitative analysis showed that, for one omission of markers ingestion, a correct diagnosis of delayed colonic transit time and of the main site of delay could be obtained by the 3-compartment model in 100% of cases. For two failures of markers ingestion, "delayed" colonic transit could be regarded as normal in only 9.59% of cases; furthermore, the site of delay was correctly recognized in 83% of the cases.

CONCLUSIONS & INFERENCES

Despite omission of markers ingestion for one or two days, measured CTT overestimates the absolute value of colonic transit time, the formulated diagnosis (delayed transit and site of delay) is perfectly acceptable clinically.

Colon capsule endoscopy vs. colonoscopy in patients at average or increased risk of colorectal cancer

BACKGROUND

Colon capsule endoscopy (CCE) is a new, non-invasive technology.

AIM

To conduct a prospective, multicentre trial to compare CCE and colonoscopy in asymptomatic subjects enrolled in screening or surveillance programmes for the detection of colorectal neoplasia.

METHODS

Patients underwent CCE on day one and colonoscopy (gold standard) on day two. CCE and colonoscopy were performed by independent endoscopists.

RESULTS

A total of 545 patients were recruited. CCE was safe and well-tolerated. Colon cleanliness was excellent or good in 52% of cases at CCE. Five patients with cancer were detected by colonoscopy, of whom two were missed by CCE. CCE accuracy for the detection of polyps ≥ 6 mm was 39% (95% CI 30-48) for sensitivity, 88% (95% CI 85-91) for specificity, 47% (95% CI 37-57) for positive predictive value and 85% (95% CI 82-88) for negative predictive value. CCE accuracy was better for the detection of advanced adenoma, in patients with good or excellent cleanliness and after re-interpretation of the CCE videos by an independent expert panel.

CONCLUSIONS

Although well-tolerated, CCE cannot replace colonoscopy as a first line investigation for screening and surveillance of patients at risk of cancer. Further studies should pay attention to colonic preparation (Clinicaltrial.gov number NCT00436514).

Identification of a functional EGF-R/p60c-src/STAT3 pathway in colorectal carcinoma: analysis of its long-term prognostic value

AIMS

The Epidermal Growth Factor-Receptor (EGF-R) is frequently overexpressed in colorectal carcinoma (CRC) and patients can benefit from anti-EGF-R therapy. Yet, the relationship, within tumours, between EGF-R and the activity of downstream effectors such as the non-receptor tyrosine kinase p60c-src and the signal transducer and activator of transcription 3 (STAT3) has not been extensively analyzed.

METHODS AND RESULTS

We evaluated EGF-R, tyrosine 416-phosphorylated p60c-src (P-p60c-src), STAT3 and tyrosine 705-phosphorylated STAT3 (P-STAT3) on Tissue Micro Array (TMA) from 126 patients with CRC. Composite immunohistochemistry scores based on the intensity of labelling and the percentage of positive cells were determined on TMA for EGF-R, P-p60c-src, STAT3 and P- STAT3. A high score was found in 56%, 61%, 62% and 27% of the cases for EGF-R, P-p60c-src, STAT3 and P-STAT3 respectively. There was a significant correlation between EGF-R and P-p60c-src (p=0.006) and between P-p60c-src and P-STAT3 (p=0.0009). STAT3 was significantly correlated with vascular emboli (p=0.03) and perineural invasion (p=0.02).

CONCLUSIONS

The correlations between EGF-R, P-p60-src and P-STAT3 and some stage-related pathological features point to a critical role for a EGF-R-connected p60c-src-kinase-mediated pathway involving STAT3 and contributing to cell survival and proliferation within CRC tumours.

Microvessel density and VEGF expression are prognostic factors in colorectal cancer. Meta-analysis of the literature

We performed a meta-analysis of all published studies relating intratumoural microvessel density (MVD) (45 studies) or vascular endothelial growth factor (VEGF) expression (27 studies), both reflecting angiogenesis, to relapse free (RFS) and overall survival (OS) in colorectal cancer (CRC). For each study, MVD impact was measured by risk ratio between the two survival distributions with median MVD as cutoff. Eleven studies did not mention survival data or fit inclusion criteria, six were multiple publications of same series, leaving 32 independent studies for MVD (3496 patients) and 18 for VEGF (2050 patients). Microvessel density was assessed by immunohistochemistry, using antibodies against factor VIII (16 studies), CD31 (10 studies) or CD34 (seven studies). Vascular endothelial growth factor expression was mostly assessed by immunohistochemistry. Statistics were performed for MVD in 22 studies (the others lacking survival statistics) including nine studies (n = 957) for RFS and 18 for OS (n = 2383) and for VEGF in 17 studies, including nine studies for RFS (n = 1064) and 10 for OS (n = 1301). High MVD significantly predicted poor RFS (RR = 2.32 95% CI: 1.39-3.90; P < 0.001) and OS (RR = 1.44; 95% CI: 1.08-1.92; P = 0.01). Using CD31 or CD34, MVD was inversely related to survival, whereas it was not using factor VIII. Vascular endothelial growth factor expression significantly predicted poor RFS (RR = 2.84; 95% CI: 1.95-4.16) and OS (RR=1.65; 95% CI: 1.27-2.14). To strengthen our findings, future prospective studies should explore the relation between MVD or VEGF expression and survival or response to therapy (e.g. antiangiogenic therapy). Assessment of these angiogenic markers should be better standardised in future studies.

Impact of EGFR expression on colorectal cancer patient prognosis and survival

BACKGROUND

Epidermal growth factor receptor (EGFR) is overexpressed in many types of cancers, especially colorectal cancer (CRC), and seems to reflect more aggressive histological and clinical behaviors. The aim of this study was to evaluate EGFR immunohistochemical reactivity in CRC biopsies, and to analyze its relationship with various histological and clinical characteristics and survival.

PATIENTS AND METHODS

A composite EGFR score, obtained by multiplying the grade (% positive cells) by the intensity of labeling (0-9) was used to define patients with low or high EGFR expression whose clinicopathological features were then compared. Univariate tests and multivariate Cox proportional hazards model were applied for data analysis.

RESULTS

Tissue sections from 150 CRC patients with a median follow-up of 40 months were examined. Median patient age at diagnosis was 70 years (range 38-89 years). EGFR reactivity was positive for 143 patients (97%) and high for 118 (80%). According to multivariate analysis, EGFR overexpression was significantly associated with tumor stage, with a higher percentage of EGFR overexpression in T3 than T4 (P=0.003) and not with overall survival.

CONCLUSIONS

EGFR was overexpressed in this CRC patient population and was significantly associated with TNM (tumor-node-metastasis) stage T3. In the context of a new therapeutic strategy using EGFR-targeted therapies, although EGFR remains a controversial prognostic factor, this expression-stage association may play a crucial role in a decision to initiate an adjuvant treatment.

[Chemoprevention of colorectal cancer]

A NEW CONCEPT: Chemoprevention of cancer consists in the administration of chemical agents to prevent or inhibit carcinogenesis. This strategy can be applied at any stage of carcinogenesis.

ASSESSMENT

The development of such agents relies on classical bases: phases I, II and III. The approach consists in assessing the effect of the substance tested in patients with history of resected adenomas of the colon and at high risk of relapse and/or family risk of colon cancer.

THE PRINCIPLE AGENTS UNDER ASSESSMENT

Are aspirin, type 2 cyclo-oxygenase inhibitors, calcium, folic acid, certain vitamins, hormone replacement therapy for menopausal women and difluoromethylornithine (DFMO).

Guar gum does not impair the absorption and utilization of dietary nitrogen but affects early endogenous urea kinetics in humans

BACKGROUND

Viscous gums enhance viscosity in the upper gastrointestinal lumen, quickly disturbing motility and promoting fluid secretion.

OBJECTIVE

We sought to determine whether guar gum could acutely affect the absorption and utilization of dietary nitrogen and whether these luminal effects could also perturb the kinetics of urea.

DESIGN

We studied the short-term effect of adding 1% of highly viscous guar gum to a (15)N-labeled protein meal (30 g soy protein isolate in 500 mL water) during the postprandial phase in humans. The effects on bioavailability were studied by using the [(13)C]glycine breath test (to assess gastric emptying) and (15)N enrichment in plasma amino acids (for systemic amino acid bioavailability). The kinetics of dietary and endogenous urea were assessed in plasma and urine.

RESULTS

Guar gum modulated the gastric emptying kinetics of the liquid phase of the meal slightly (P < 0.05), but had no significant effect on either the systemic appearance of dietary amino acids or plasma and urinary dietary urea kinetics. Without significantly affecting plasma urea concentrations, guar gum reduced by approximately 40% the urinary excretion of endogenous urea for the first 2-h period after the meal (P < 0.01), although endogenous urinary excretion was similar at later stages.

CONCLUSIONS

Guar gum did not significantly affect the bioavailability or utilization of dietary protein. We showed an early effect of guar gum on endogenous urea kinetics, which most probably arose from very early, short-term stimulation of the intestinal disposal of endogenous urea, at the expense of its urinary excretion.

Kirsten ras mutations in patients with colorectal cancer: the 'RASCAL II' study

Researchers worldwide with information about the Kirsten ras (Ki-ras) tumour genotype and outcome of patients with colorectal cancer were invited to provide that data in a schematized format for inclusion in a collaborative database called RASCAL (The Kirsten ras in-colorectal-cancer collaborative group). Our results from 2721 such patients have been presented previously and for the first time in any common cancer, showed conclusively that different gene mutations have different impacts on outcome, even when the mutations occur at the same site on the genome. To explore the effect of Ki-ras mutations at different stages of colorectal cancer, more patients were recruited to the database, which was reanalysed when information on 4268 patients from 42 centres in 21 countries had been entered. After predetermined exclusion criteria were applied, data on 3439 patients were entered into a multivariate analysis. This found that of the 12 possible mutations on codons 12 and 13 of Kirsten ras, only one mutation on codon 12, glycine to valine, found in 8.6% of all patients, had a statistically significant impact on failure-free survival (P = 0.004, HR 1.3) and overall survival (P = 0.008, HR 1.29). This mutation appeared to have a greater impact on outcome in Dukes' C cancers (failure-free survival, P = 0.008, HR 1.5; overall survival P = 0.02, HR 1.45) than in Dukes' B tumours (failure-free survival, P = 0.46, HR 1.12; overall survival P = 0.36, HR 1.15). Ki-ras mutations may occur early in the development of pre-cancerous adenomas in the colon and rectum. However, this collaborative study suggests that not only is the presence of a codon 12 glycine to valine mutation important for cancer progression but also that it may predispose to more aggressive biological behaviour in patients with advanced colorectal cancer.

APACC, a French prospective study on aspirin efficacy in reducing colorectal adenoma recurrence: design and baseline findings

Colorectal cancer is the second most frequent cause of death from cancer in western countries. Many lines of evidence suggest that non-steroidal anti-inflammatory drugs (NSAIDs) may offer chemoprevention against colorectal cancer. A multicentre, double-blind, randomized, controlled trial is underway to determine the efficacy of regular aspirin intake (160 or 300 mg/day) in reducing colorectal adenoma recurrence. We now report the baseline characteristics of subjects enrolled into the trial.

RESULTS

A total of 618 polyps were excised from 274 patients at the baseline colonoscopy. Men had on average (+/-SD) 2.5 +/- 1.8 polyps per subject and women had 1.7 +/- 1.2. Ninety-one (33.7%) had three or more adenomas and 183 (67.8%) had more than one adenoma measuring 10 mm or more in diameter. The mean (+/-SD) age of the subjects was 57.7 (+/- 9.4) years. Sixty-seven (24.9%) reported that they had previously had adenoma(s), 95 (35.2%) reported a family history of colorectal cancer and 41 (15.2%) a family history of colorectal adenomas.

PERSPECTIVE

All subjects will undergo a one-year clearance colonoscopy by February 2001. Clinical, molecular biological and dietary data will enable us to investigate other factors influencing the recurrence of adenomas in this group of high-risk subjects.

The influence of the albumin fraction on the bioavailability and postprandial utilization of pea protein given selectively to humans

Pulse seed proteins such as those found in peas (Pisum sativum) contain fractions of very dissimilar composition and properties, which may therefore be differently utilized by the human body. To analyze the nutritional value of the soluble protein fractions of pea seed, human volunteers ingested a mixed meal of 30 g of raw purified pea protein either as [15N]-globulins (G, n = 9) or as a mix of [15N]-globulins and [15N]-albumins (GA, n = 7) in their natural proportions (22:8). Dietary and endogenous nitrogen fluxes at the terminal ileum were assessed using a tube perfusion technique with an isotopic dilution method. Systemic dietary amino acid availability and the retention of dietary amino acids were determined using 15N enrichment in plasma amino acids and deamination products in blood and urine for 8 h postprandially. The results showed that the pea albumin fraction had the following effects: 1) significantly lowered the real ileal digestibility of pea protein (94 +/- 2.5% for G vs. 89.9 +/- 4% for GA), probably because of a direct effect of trypsin inhibitors; 2) did not promote acute intestinal losses of endogenous nitrogen; and 3) did not significantly improve the postprandial biological value of pea protein (76.5 +/- 3.9% for G vs. 78.7 +/- 3.6% for GA), despite the fact that it corrected the globulin deficiency in sulfur amino acids. We conclude that both G and GA are of good nutritional value for humans and show that cysteine-rich albumins have a far more modest effect on the efficiency of postprandial dietary protein utilization than would be expected from the amino acid scores.

Nutritional status after short-term dietary supplementation in hospitalized malnourished geriatric patients

AIM

To examine the evolution of different parameters of the nutritional status after short-term oral protein-energy supplementation in moderately malnourished geriatric patients.

METHODS

Seventeen hospitalized malnourished elderly patients and 12 healthy adults received dietary supplements for 10 days. A group of six malnourished elderly subjects served as controls. Spontaneous oral intakes, biological and biophysical markers of the nutritional status were measured. Fat-free mass (FFM) was assessed using Dual energy X-ray absorptiometry (DXA), bio-impedance analysis (BIA) and anthropometry.

RESULTS

In elderly subjects, the supplementation significantly increased both dietary intake (energy +32%, protein +65%) and FFM (+1.3 kg, P<0.001) as assessed using DXA. BIA and anthropometric data correlated with DXA measurements in the elderly (BIA: r=0.68--0.80, anthropometry: r=0.80--0.89), but failed to reflect accurately the changes measured in FFM. Supplementation had no notable effect on biological markers in any of the groups. IGF-I and hand-grip strength were not significantly influenced by the supplementation despite trends towards an improvement.

CONCLUSIONS

Monitoring short-term changes in nutritional status in malnourished elderly individuals is a problem in routine clinical management. Our data put in the limelight the changes in IGF-I values related to dietary supplementation, and, chiefly, suggest a prime role for the assessment of dietary intake and FFM, as assessed by DXA, as indicators of short-term efficacy of refeeding. Nevertheless larger studies are necessary to confirm the clinical and prognostic significance of the changes.