[Spontaneous pulmonary hematoma in patients with COVID-19]

The disease caused by Sars-Cov-2 (Covid-19) has become a worldwide pandemic and consequently a public health problem. Multiple complications associated with Covid-19 have been described, including coagulation abnormalities. Although the infection is known to induce a prothrombotic state, hemorrhagic complications have also been reported in patients with Covid-19, especially in anticoagulated patients. We present two cases of spontaneous pulmonary hematoma in patients with Covid-19 undergoing anticoagulant treatment. We aim to describe this complication, which although uncommon, should be taken into account in anticoagulated patients with Covid-19.

Memory T Cell Subpopulations as Early Predictors of Remission to Vedolizumab in Ulcerative Colitis

Background

Vedolizumab is a humanized monoclonal antibody targeting the α₄β₇ integrin used for the treatment of ulcerative colitis. Few biomarkers related to vedolizumab response have been identified. The aim of this work was to assess whether baseline circulating CD4⁺ and CD8⁺ memory T-lymphocyte subpopulations could help to identify patients with response to vedolizumab treatment in ulcerative colitis.

Methods

Prospective pilot study in 15 patients with active ulcerative colitis and previous failure to anti-TNFα starting vedolizumab treatment. Peripheral blood samples were obtained before the first dose of vedolizumab and at week 6 and 14 of treatment. Clinical remission was defined as a Mayo Clinic partial score of ≤2 points without any concomitant dose of steroids. Biochemical remission or endoscopic improvement was defined as fecal calprotectin <250 mcg/g or Mayo endoscopic subscore ≤1.

Results

At week 14, nine patients achieved clinical remission and eight patients achieved biochemical remission or endoscopic improvement. Patients in clinical remission presented higher baseline CD8 α₄β₇⁺ memory T cells concentration when compared with patients with no remission. In addition, patients with biochemical remission or endoscopic improvement at week 14 presented higher baseline concentration of CD8 α₄β₇⁺ memory T cells. No differences were identified according to flare severity, extent of disease or type of anti-TNFα failure. There were no significant differences regarding changes in T cell subsets during vedolizumab induction.

Conclusion

CD8⁺ α₄β₇⁺ memory T cells before starting vedolizumab therapy could be an early predictor of remission in ulcerative colitis patients and therefore help to select a subset of responders.

Predictors of Metachronous Risk Polyps After Index Colonoscopy

INTRODUCTION

Guidelines for surveillance after polypectomy are lacking in strong evidence. Our aim was to identify some precursors of colorectal cancer lesions at 3 years after polypectomy to improve stratification and surveillance programs.

METHODS

We included patients with high-risk lesions (HRLs), defined as advanced adenoma (AA), large serrated polyps (SPs), and multiplicity (≥3 of any adenomas/SPs). Data on age, sex, cardiovascular risk factors, pharmacological treatment, and the histological characteristics in each individual, and mutations in genes involved in the most advanced index polyp, were collected. Parameters independently associated with a metachronous HRL diagnosis were evaluated through univariate and multivariate analyses. The results are reported as odds ratios and 95% confidence intervals along with P values.

RESULTS

A total of 537 cases (median age: 60.7 years; 66% male) were included. Dyslipidemia and smoking correlated with metachronous HRLs. Multivariate logistic regression analysis showed that the presence of multiplicity with ≥3 polyps on the index colonoscopy was significantly associated with metachronous HRL, AA, proximal AA, and ≥3 polyps at 3 years. In addition, independent predictors of metachronous proximal AA were increasing age, female sex, and the loss of expression of the MLH1 protein.

DISCUSSION

Multiplicity was a strong predictor of HRLs at 3 years, although the inclusion of other clinical variables (age, sex, smoking status, and dyslipidemia) improves surveillance recommendations. Without these risk factors, the surveillance could be extended to 5 years; we propose examining the somatic expression of MHL1 in all patients.

Narrow-band imaging and high-definition white-light endoscopy in patients with serrated lesions not fulfilling criteria for serrated polyposis syndrome: a randomized controlled trial with tandem colonoscopy

BACKGROUND

It is unknown whether narrow-band imaging (NBI) could be more effective than high-definition white-light endoscopy (HD-WLE) in detecting serrated lesions in patients with prior serrated lesions > 5 mm not completely fulfilling serrated polyposis syndrome (SPS) criteria.

METHODS

We conducted a randomized, cross-over trial in consecutive patients with prior detection of at least one serrated polyp ≥10 mm or ≥ 3 serrated polyps larger than 5 mm, both proximal to the sigmoid colon. Five experienced endoscopists performed same-day tandem colonoscopies, with the order being randomized 1:1 to NBI-HD-WLE or HD-WLE-NBI. All tandem colonoscopies were performed by the same endoscopist.

RESULTS

We included 41 patients. Baseline characteristics were similar in the two cohorts: NBI-HD-WLE (n = 21) and HD-WLE-NBI (n = 20). No differences were observed in the serrated lesion detection rate of NBI versus HD-WLE: 47.4% versus 51.9% (OR 0.84, 95% CI: 0.37-1.91) for the first and second withdrawal, respectively. Equally, no differences were found in the polyp miss rate of NBI versus HD-WLE: 21.3% versus 26.1% (OR 0.77, 95% CI: 0.43-1.38). Follow-up colonoscopy in nine patients (22%) allowed them to be reclassified as having SPS.

CONCLUSIONS

In patients with previous serrated lesions, the serrated lesion detection rate was similar with NBI and HD-WLE. A shorter surveillance colonoscopy interval increases the detection of missed serrated polyps and could change the diagnosis of SPS in approximately one in every five patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02406547, registered on April 2, 2015.

Clinical Characteristics, Associated Malignancies and Management of Primary Sclerosing Cholangitis in Inflammatory Bowel Disease Patients: A Multicentre Retrospective Cohort Study

BACKGROUND AND AIMS

Primary sclerosing cholangitis [PSC] is usually associated with inflammatory bowel disease [IBD]. An increased risk of malignancies, mainly colorectal cancer [CRC] and cholangiocarcinoma [CCA], has been reported in PSC-IBD patients. Our aim was to determine the clinical characteristics and management of PSC in IBD patients, and the factors associated with malignancies.

METHODS

PSC-IBD patients were identified from the Spanish ENEIDA registry of GETECCU. Additional data were collected using the AEG-REDCap electronic data capture tool.

RESULTS

In total, 277 PSC-IBD patients were included, with an incidence rate of 61 PSC cases per 100 000 IBD patient-years, 69.7% men, 67.5% ulcerative colitis and mean age at PSC diagnosis of 40 ± 16 years. Most patients [85.2%] were treated with ursodeoxycholic acid. Liver transplantation was required in 35 patients [12.6%] after 79 months (interquartile range [IQR] 50-139). It was more common in intra- and extrahepatic PSC compared with small-duct PSC (16.3% vs 3.3%; odds ratio [OR] 5.7: 95% confidence interval [CI] = 1.7-19.3). The incidence rate of CRC since PSC diagnosis was 3.3 cases per 1000 patient-years [95% CI = 1.9-5.6]. Having symptoms of PSC at PSC diagnosis was the only factor related to an increased risk of CRC after IBD diagnosis [hazard ratio= 3.3: 95% CI = 1.1-9.9]. CCA was detected in seven patients [2.5%] with intra- and extrahepatic PSC, with median age of 42 years [IQR 39-53], and presented a lower life expectancy compared with patients without CCA and patients with or without CRC.

CONCLUSIONS

PSC-IBD patients with symptoms of PSC at PSC diagnosis have an increased risk of CRC. CCA was only diagnosed in patients with intra- and extrahepatic PSC and was associated with poor survival.

Narrow band imaging and white light endoscopy in the characterization of a polypectomy scar: A single-blind observational study

AIM

To assess the incremental benefit of narrow band imaging (NBI) and white light endoscopy (WLE), randomizing the initial technique for the detection of residual neoplasia at the polypectomy scar after an endoscopic piecemeal mucosal resection (EPMR).

METHODS

We conducted an observational study in an academic center to assess the incremental benefit of NBI and WLE randomly applied 1:1 (NBI-WLE or WLE-NBI) in the follow-up of a post-EPMR scar by the same endoscopist.

RESULTS

A total of 112 EPMR scars were included. The median baseline polyp size was 20 mm (interquartile range: 14-30). At first review, NBI and WLE showed good sensitivity (85.0% vs 78.9%), specificity (77.1% vs 84.2%) and overall accuracy (80.0% vs 82.5%). NBI after WLE (WLE-NBI group) improved accuracy, but this difference was not statistically significant [area under the curve (AUC): 86.8% vs 81.6%, P = 0.15]. WLE after NBI (NBI-WLE group) did not improve accuracy (AUC: 81.4% vs 81.1%, P = 0.9). Overall, recurrence was found in 39/112 (34.8%) lesions.

CONCLUSION

Although no statistically significant differences were found between the two techniques at the first post-EPMR assessment, the use of NBI after WLE may improve residual neoplasia detection. Nevertheless, biopsy is still required in the first scar review.

Short and long-term effectiveness and safety of vedolizumab in inflammatory bowel disease: results from the ENEIDA registry

BACKGROUND

Effectiveness of vedolizumab in real world clinical practice is unknown.

AIM

To evaluate the short and long-term effectiveness of vedolizumab in patients with inflammatory bowel disease (IBD).

METHODS

Patients who received at least 1 induction dose of vedolizumab were included. Effectiveness was defined based on Harvey-Bradshaw index (HBI) in Crohn's disease (CD) and Partial Mayo Score (PMS) in ulcerative colitis (UC). Short-term response was assessed at week 14. Variables associated with short-term remission were identified by logistic regression analysis. The Kaplan-Meier method was used to evaluate the long-term durability of vedolizumab treatment. Cox model was used to identify factors associated with discontinuation of treatment and loss of response.

RESULTS

521 patients were included (median follow-up 10 months [interquartile range 5-18 months]). At week 14, 46.8% had remission and 15.7% clinical response. CD (vs UC), previous surgery, higher CRP concentration and disease severity at baseline were significantly associated with impaired response. The rate of vedolizumab discontinuation was 37% per patient-year of follow-up (27.6% in UC and 45.3% in CD, P < 0.01). CD (vs UC), anaemia at baseline, steroids during induction and CRP concentration were associated with lower durability of treatment. Seven per cent of patients developed adverse events, infections being the most frequent.

CONCLUSIONS

Over 60% of IBD patients respond to vedolizumab. Many patients discontinue treatment over time. CD and disease burden impair both short- and long-term response. Vedolizumab seems to be safe in clinical practice.

Detection of serrated lesions in proximal colon by simulated sigmoidoscopy vs faecal immunochemical testing in a multicentre, pragmatic, randomised controlled trial

Background

The diagnostic yield of the faecal immunochemical test and sigmoidoscopy in detecting proximal serrated polyps in a colorectal cancer screening programme has not been fully assessed.

Aim

We determined the detection rate of proximal serrated polyps by simulated sigmoidoscopy and faecal immunochemical test compared with total colonoscopy in a population-based, multicentre, nationwide, randomised controlled trial (ColonPrev study).

Methods

Sigmoidoscopy yield was simulated based on the UK-Flexible Sigmoidoscopy Trial for total colonoscopy referral. Definitions were: proximal serrated polyp (proximal serrated polyp): sessile serrated polyp or hyperplastic polyp of any size and proximal at-risk serrated polyp (at-risk proximal serrated polyp): sessile serrated polyp of any size or hyperplastic polyp ≥ 10 mm, both located proximally to the splenic flexure.

Results

A total of 10,611 individuals underwent faecal immunochemical test and 5059 underwent total colonoscopy and were evaluated by simulated sigmoidoscopy. Sigmoidoscopy and faecal immunochemical test were less accurate in detecting proximal serrated polyps (odds ratio: 0.13; 95% confidence interval: 0.10-0.18 and 0.13; 0.09-0.18, p < 0.0001, respectively). Both tests were inferior to colonoscopy in detecting at-risk proximal serrated polyps, and sigmoidoscopy was inferior to faecal immunochemical test in detecting these lesions (odds ratio: 0.17; 95% confidence interval: 0.10-0.30 and 0.25; 0.17-0.37, p < 0.0001, respectively).

Conclusion

Sigmoidoscopy and faecal immunochemical test are less accurate in detecting proximal serrated polyps than colonoscopy, particularly in women.

Colorectal cancer molecular classification using BRAF, KRAS, microsatellite instability and CIMP status: Prognostic implications and response to chemotherapy

Objective

The aim of this study was to validate a molecular classification of colorectal cancer (CRC) based on microsatellite instability (MSI), CpG island methylator phenotype (CIMP) status, BRAF, and KRAS and investigate each subtype’s response to chemotherapy.

Design

This retrospective observational study included a population-based cohort of 878 CRC patients. We classified tumours into five different subtypes based on BRAF and KRAS mutation, CIMP status, and MSI. Patients with advanced stage II (T4N0M0) and stage III tumours received 5-fluoruracil (5-FU)-based chemotherapy or no adjuvant treatment based on clinical criteria. The main outcome was disease-free survival (DFS).

Results

Patients with the combination of microsatellite stable (MSS) tumours, BRAF mutation and CIMP positive exhibited the worst prognosis in univariate (log rank P<0.0001) and multivariate analyses (hazard ratio 1.75, 95% CI 1.05–2.93, P = 0.03) after adjusting for age, sex, chemotherapy, and TNM stage. Treatment with 5-FU-based regimens improved prognosis in patients with the combination of MSS tumours, KRAS mutation and CIMP negative (log rank P = 0.003) as well as in patients with MSS tumours plus BRAF and KRAS wild-type and CIMP negative (log-rank P<0.001). After adjusting for age, sex, and TNM stage in the multivariate analysis, only patients with the latter molecular combination had independently improved prognosis after adjuvant chemotherapy (hazard ratio 2.06, 95% CI 1.24–3.44, P = 0.005).

Conclusion

We confirmed the prognostic value of stratifying CRC according to molecular subtypes using MSI, CIMP status, and somatic KRAS and BRAF mutation. Patients with traditional chromosomally unstable tumours obtained the best benefit from adjuvant 5-FU-based chemotherapy.

Population-based colorectal cancer screening: Interval cancers and relationship with the quantitative faecal immunological for hemoglobin

INTRODUCTION AND OBJECTIVE

The sensitivity of colorectal cancer screening programmes determines their effectiveness and is directly related to the interval cancer (IC). This study describes the frequency and characteristics of the IC of the Programme of Barcelona, Spain, and analyses its relationship with the quantitative value of the screening test (FIT).

MATERIAL AND METHODS

ICs after negative FIT of the first two rounds of the Programme (2010-2013) were included, observation period until July 2017. The information source of the ICs was their notification by professionals and patients, hospital databases and CMBD (Spanish Minimum Basic Data Set).

RESULTS

The sensitivity of the Programme is 82%. ICs are diagnosed more in proximal and rectal colon and in advanced stages than screening cancers, and have higher FIT values than overall people with negative FIT.

CONCLUSIONS

The sensitivity is acceptable and comparable to that of other programmes. The quantitative value of FIT in people with negative test should be included in the personalisation strategies of screening to reduce the risk of IC.

TFAP2E Methylation and Expression Status Does Not Predict Response to 5-FU-based Chemotherapy in Colorectal Cancer

Purpose: A recent study reported that 5-fluorouracil (5-FU)-based chemotherapy is less effective in treating patients with advanced colorectal cancer demonstrating hypermethylation of the TFAP2E gene. The aim of our study was to confirm and validate these findings in large, uniformly treated, well-characterized patient cohorts.Experimental Design: Two cohorts of 783 patients with colorectal cancer: 532 from a population-based, multicenter cohort (EPICOLON I) and 251 patients from a clinic-based trial were used to study the effectiveness of TFAP2E methylation and expression as a predictor of response of colorectal cancer patients to 5-FU-based chemotherapy. DNA methylation status of the TFAP2E gene in patients with colorectal cancer was assessed by quantitative bisulfite pyrosequencing analysis. IHC analysis of the TFAP2E protein expression was also performed.Results: Correlation between TFAP2E methylation status and IHC staining was performed in 607 colorectal cancer samples. Among 357 hypermethylated tumors, only 141 (39.6%) exhibited loss of protein expression. Survival was not affected by TFAP2E hypermethylation in stage IV patients [HR, 1.21; 95% confidence interval (CI), 0.79-1.87; log-rank P = 0.6]. In stage II-III cases, disease-free survival was not influenced by TFAP2E hypermethylation status in 5-FU-treated (HR, 0.91; 95% CI, 0.52-1.59; log-rank P = 0.9) as well as in nontreated patients (HR, 0.88; 95% CI, 0.5-1.54; log-rank P = 0.7).Conclusions:TFAP2E hypermethylation does not correlate with loss of its protein expression. Our large, systematic, and comprehensive study indicates that TFAP2E methylation and expression may not play a major role in predicting response to 5-FU-based chemotherapy in patients with colorectal cancer. Clin Cancer Res; 24(12); 2820-7. ©2018 AACR.

Meat intake, cooking methods and doneness and risk of colorectal tumours in the Spanish multicase-control study (MCC-Spain)

PURPOSE

Although there is convincing evidence that red and processed meat intake increases the risk of colorectal cancer (CRC), the potential role of meat cooking practices has not been established yet and could partly explain the current heterogeneity of results among studies. Therefore, we aimed to investigate the association between meat consumption and cooking practices and the risk of CRC in a population-based case-control study.

METHODS

A total of 1671 CRC cases and 3095 controls recruited in Spain between September 2008 and December 2013 completing a food frequency questionnaire with a meat-specific module were included in the analyses. Odds ratios (OR) and confidence intervals (CI) were estimated by logistic regression models adjusted for known confounders.

RESULTS

Total meat intake was associated with increased risk of CRC (OR T3-T1 1.41; 95% CI 1.19-1.67; p trend < 0.001), and similar associations were found for white, red and processed/cured/organ meat. Rare-cooked meat preference was associated with low risk of CRC in red meat (ORrare vs. medium 0.66; 95% CI 0.51-0.85) and total meat (ORrare vs. medium 0.56; 95% CI 0.37-0.86) consumers, these associations being stronger in women than in men. Griddle-grilled/barbecued meat was associated with an increased CRC risk (total meat: OR 1.45; 95% CI 1.13-1.87). Stewing (OR 1.25; 95% CI 1.04-1.51) and oven-baking (OR 1.18; 95% CI 1.00-1.40) were associated with increased CRC risk of white, but not red, meat.

CONCLUSIONS

Our study supports an association of white, red, processed/cured/organ and total meat intake with an increased risk of CRC. Moreover, our study showed that cooking practices can modulate such risk.

Colorectal cancer molecular classification using BRAF, KRAS, microsatellite instability, and CIMP status: Prognostic implications and response to chemotherapy

668

Background: The aim of this study was to validate a molecular classification of colorectal cancer (CRC) based on microsatellite instability (MSI), CpG island methylator phenotype (CIMP) status, BRAF, and KRAS and investigate each subtype’s response to chemotherapy. Methods: This retrospective observational study included a population-based cohort of 878 CRC patients. We classified tumours into five different subtypes based on BRAF and KRAS mutation, CIMP status, and MSI. Patients with advanced stage II (T4N0M0) and stage III tumours received 5-fluoruracil (5-FU)-based chemotherapy or no adjuvant treatment based on clinical criteria. The main outcome was disease-free survival (DFS). Results: Patients with the combination of microsatellite stable (MSS) tumours, BRAF mutation and CIMP positive exhibited the worst prognosis in univariate (log rank P < 0.0001) and multivariate analyses (hazard ratio 1.75, 95% CI 1.05-2.93, P = 0.03) after adjusting for age, sex, chemotherapy, and TNM stage. Treatment with 5-FU-based regimens improved prognosis in patients with the combination of MSS tumours, KRAS mutation and CIMP negative (log rank P = 0.003) as well as in patients with MSS tumours plus BRAF and KRAS wild-type and CIMP negative (log-rank P < 0.001). After adjusting for age, sex, and TNM stage in the multivariate analysis, only patients with the latter molecular combination had independently improved prognosis after adjuvant chemotherapy (hazard ratio 2.06, 95% CI 1.24-3.44, P = 0.005). Conclusions: We confirmed the prognostic value of stratifying CRC according to molecular subtypes using MSI, CIMP status, and somatic KRAS and BRAF mutation. Patients with traditional chromosomally unstable tumours obtained the best benefit from adjuvant 5-FU-based chemotherapy.

Relationship between drugs affecting the renin-angiotensin system and colorectal cancer: The MCC-Spain study

The potential protective effect of renin-angiotensin system (RAS) inhibitors is a subject of increasing interest due to their possible role as chemopreventive agents against colorectal cancer (CRC). To evaluate this association, we conducted a case-control study with 2165 cases of colorectal cancer, diagnosed between 2007 and 2012, and 3912 population controls frequency matched (by age, sex and region) from the Spanish multicenter case-control study MCC-Spain. We found a significant protective effect of the angiotensin-converting enzyme Inhibitors (ACEIs) against CRC, limited to the under-65years group (OR=0.65 95%CI (0.48-0.89)) and to a lesser degree to men (OR=0.81 95%CI (0.66-0.99). In contrast, the angiotensin receptor blockers (ARBs) did not show a significant effect. Regarding the duration of use, a greater protection was observed in men as the length of consumption increases. In contrast, in the under-65 stratum, the strongest association was found in short-term treatments. Finally, by analyzing ACEIs effect by colon subsite, we found no differences, except for under 65years old, where the maximum protection was seen in the proximal intestine, descending in the distal and rectum (without statistical significance). In conclusion, our study shows a protective effect on CRC of the ACEis limited to males and people under 65years old, which increases in proximal colon in the latter. If confirmed, these results may suggest a novel approach to proximal CRC prevention, given the shortcomings of colonoscopy screening in this location.

Methylation of WNT target genes AXIN2 and DKK1 as robust biomarkers for recurrence prediction in stage II colon cancer

Stage II colon cancer (CC) still remains a clinical challenge with patient stratification for adjuvant therapy (AT) largely relying on clinical parameters. Prognostic biomarkers are urgently needed for better stratification. Previously, we have shown that WNT target genes AXIN2, DKK1, APCDD1, ASCL2 and LGR5 are silenced by DNA methylation and could serve as prognostic markers in stage II CC patients using methylation-specific PCR. Here, we have extended our discovery cohort AMC90-AJCC-II (N=65) and methylation was analyzed by quantitative pyrosequencing. Subsequently, we validated the results in an independent EPICOLON1 CC cohort (N=79). Methylation of WNT target genes is negatively correlated to mRNA expression. A combination of AXIN2 and DKK1 methylation significantly predicted recurrences in univariate (area under the curve (AUC)=0.83, confidence interval (CI): 0.72–0.94, P<0.0001) analysis in stage II microsatellite stable (MSS) CC patients. This two marker combination showed an AUC of 0.80 (CI: 0.68–0.91, P<0.0001) in the EPICOLON1 validation cohort. Multivariate analysis in the Academic Medical Center (AMC) cohort revealed that both WNT target gene methylation and consensus molecular subtype 4 (CMS4) are significantly associated with poor recurrence-free survival (hazard ratio (HR)_methylation: 3.84, 95% CI: 1.14–12.43; HR_CMS4: 3.73, 95% CI: 1.22–11.48). CMS4 subtype tumors with WNT target methylation showed worse prognosis. Combining WNT target gene methylation and CMS4 subtype lead to an AUC of 0.89 (0.791–0.982, P<0.0001) for recurrence prediction. Notably, we observed that methylation of DKK1 is high in BRAF mutant and CIMP (CpG island methylator phenotype)-positive cancers, whereas AXIN2 methylation appears to be associated with CMS4. Methylation of AXIN2 and DKK1 were found to be robust markers for recurrence prediction in stage II MSS CC patients. Further validation of these findings in a randomized and prospective manner could pave a way to identify poor prognosis patients of stage II CC for AT.

Long-Term Prediction of the Demand of Colonoscopies Generated by a Population-Based Colorectal Cancer Screening Program

OBJECTIVE

To estimate the long-term need for colonoscopies after a positive fecal immunochemical test (FIT) and post-polypectomy surveillance in the context of a population-based colorectal cancer (CRC) screening program.

METHODS

A discrete-event simulation model was built to reproduce the process of CRC screening and post-polypectomy surveillance following European guidelines in a population of 100,000 men and women aged 50-69 years over a 20-year period. Screening consisted of biennial FIT and colonoscopy in participants with positive results. The model was mainly fed using data from the first and second rounds of a Spanish program (2010-2013). Data on post-polypectomy surveillance results were obtained from the literature. A probabilistic multivariate sensitivity analysis was performed on the effect of participation, FIT positivity, and adherence to surveillance colonoscopies. The main outcome variables were the number of colonoscopies after a positive FIT, surveillance colonoscopies, and the overall number of colonoscopies.

RESULTS

An average yearly number of 1,200 colonoscopies after a positive FIT were predicted per 100,000 inhabitants with a slight increase to 1,400 at the end of the 20-year period. Surveillance colonoscopies increased to an average of 1,000 per 100,000 inhabitants in the long-term, showing certain stabilization in the last years of the 20-year simulation horizon. The results were highly sensitive to FIT positivity.

CONCLUSIONS

Implementing a population-based CRC screening program will increase the demand for colonoscopies, which is expected to double in 20 years, mainly due to an increase in surveillance colonoscopies.

Correlation between adenoma detection rate in colonoscopy- and fecal immunochemical testing-based colorectal cancer screening programs

BACKGROUND

The adenoma detection rate (ADR) is the main quality indicator of colonoscopy. The ADR recommended in fecal immunochemical testing (FIT)-based colorectal cancer screening programs is unknown.

METHODS

Using the COLONPREV (NCT00906997) study dataset, we performed a post-hoc analysis to determine if there was a correlation between the ADR in primary and work-up colonoscopy, and the equivalent figure to the minimal 20% ADR recommended. Colonoscopy was performed in 5722 individuals: 5059 as primary strategy and 663 after a positive FIT result (OC-Sensor™; cut-off level 15 µg/g of feces). We developed a predictive model based on a multivariable lineal regression analysis including confounding variables.

RESULTS

The median ADR was 31% (range, 14%-51%) in the colonoscopy group and 55% (range, 21%-83%) in the FIT group. There was a positive correlation in the ADR between primary and work-up colonoscopy (Pearson's coefficient 0.716; p < 0.001). ADR in the FIT group was independently related to ADR in the colonoscopy group: regression coefficient for colonoscopy ADR, 0.71 (p = 0.009); sex, 0.09 (p = 0.09); age, 0.3 (p = 0.5); and region 0.00 (p = 0.9). The equivalent figure to the 20% ADR was 45% (95% confidence interval, 35%-56%).

CONCLUSIONS

ADR in primary and work-up colonoscopy of a FIT-positive result are positively and significantly correlated.

Anorectal dysfunction in multiple sclerosis

Objective To ascertain the prevalence of anorectal dysfunction (ARD) in patients with multiple sclerosis (MS) and its relationship with MS clinical characteristics.

Methods Prospective transversal study in 193 patients with MS. All patients fulfilled a protocol that included: demographic variables, clinical characteristics of MS and the presence of ARD and urinary dysfunction (UD).

Results One hundred and ninety-three patients: 66.8% women, an average age of 42.8 (12.1) years; 67.8% of patients had relapsing-remitting MS, 21.2% a secondary progressive and 10.9% a primary progressive form. The average duration of MS was 10.7 (9.4) years and the EDSS 2.8 (2.3). ARD was present in 93 patients (48.2%), and UD in 50.2%. ARD associated to UD was present in 35.7% of cases. The univariate study revealed that patients with ARD were older (p<0.001), had greater disability (p<0.0001), longer disease duration (p<0.001) and a greater association with UD (p<0.0001). ARD was more frequent in progressive forms (p<0.0001). The logistic regression analysis showed that female sex ( P=0.015), EDSS ( P=0.002) and UD ( P=0.003) were independent factors related to ARD.

Conclusion ARD is a highly prevalent disorder in MS. Female sex, EDSS and UD are independent predictors of ARD development.

Association of a let-7 miRNA binding region of TGFBR1 with hereditary mismatch repair proficient colorectal cancer (MSS HNPCC)

The purpose of this study was to identify novel colorectal cancer (CRC)-causing alleles in unexplained familial CRC cases. In order to do so, coding regions in five candidate genes (MGMT, AXIN2, CTNNB1, TGFBR1 and TGFBR2) were sequenced in 11 unrelated microsatellite-stable hereditary non-polyposis CRC (MSS HNPCC) cases. Selected genetic variants were genotyped in a discovery set of 27 MSS HNPCC cases and 85 controls. One genetic variant, rs67687202, in TGFBR1 emerged as significant (P = 0.002), and it was genotyped in a replication set of 87 additional MSS HNPCC-like cases and 338 controls where it was also significantly associated with MSS HNPCC cases (P = 0.041). In the combined genotype data, rs67687202 was associated with a moderate increase in CRC risk (OR = 1.68; 95% CI = 1.13-2.50; P = 0.010). We tested a highly correlated SNP rs868 in 723 non-familial CRC cases compared with 629 controls, and it was not significantly associated with CRC risk (P = 0.370). rs868 is contained in a let-7 miRNA binding site in the 3'UTR of TGFBR1, which might provide a functional basis for the association in MSS HNPCC. In luciferase assays, the risk-associated allele for rs868 was associated with half the luciferase expression in the presence of miRNA let-7b-5p compared with protective allele, suggesting more binding of let-7b-5p and less TGFBR1 expression. Thus, rs868 potentially is a CRC risk-causing allele. Our results support the concept that rs868 is associated with lower TGFBR1 expression thereby increasing CRC risk.

Impact of age- and gender-specific cut-off values for the fecal immunochemical test for hemoglobin in colorectal cancer screening

BACKGROUND

There is no information on the impact of age and gender on the diagnostic yield of different positivity thresholds for the fecal immunochemical test for hemoglobin (FIT).

OBJECTIVES

To evaluate the performance of this test at distinct positivity cut-offs in a population-based colorectal cancer (CRC) screening program.

METHODS

CRC detection rate (DR), and analysis of resources were evaluated retrospectively, at different cut-offs of FIT (20, 25, 30, 35 and 40μg Hb/g) respect to a reference value (15μg Hb/g), according to age and gender, in a screening population of 10,611 participants of the ColonPrev study (Quintero. NEJM 2013).

RESULTS

At the reference cut-off value, 36 CRC and 252 advanced adenomas (AA) were diagnosed. Increasing the cut-off in women ≤60 years decreases colonoscopies performed by 44.5% without modifying the CRC (DR). Same CRC DR was observed in men ≤60 years and women >60 years increasing cut-off at 25-30μg Hb/g. In men >60 years, all increases in the cut-off affected the CRC DR, especially when the cut-off was increased from 35 to 40μg Hb/g (CRC miss rate 25%).

CONCLUSIONS

To improve the performance of FIT in CRC screening programs, FIT cut-offs could be individualized by age and gender.

Genetic Variants Associated with Colorectal Adenoma Susceptibility

Background

Common low-penetrance genetic variants have been consistently associated with colorectal cancer risk.

Aim

To determine if these genetic variants are associated also with adenoma susceptibility and may improve selection of patients with increased risk for advanced adenomas and/or multiplicity (≥ 3 adenomas).

Methods

We selected 1,326 patients with increased risk for advanced adenomas and/or multiplicity and 1,252 controls with normal colonoscopy from population-based colorectal cancer screening programs. We conducted a case-control association study analyzing 30 colorectal cancer susceptibility variants in order to investigate the contribution of these variants to the development of subsequent advanced neoplasia and/or multiplicity.

Results

We found that 14 of the analyzed genetic variants showed a statistically significant association with advanced adenomas and/or multiplicity: the probability of developing these lesions increased with the number of risk alleles reaching a 2.3-fold risk increment in individuals with ≥ 17 risk alleles.

Conclusions

Nearly half of the genetic variants associated with colorectal cancer risk are also related to advanced adenoma and/or multiplicity predisposition. Assessing the number of risk alleles in individuals within colorectal cancer screening programs may help to identify better a subgroup with increased risk for advanced neoplasia and/or multiplicity in the general population.

[Protocol for neurophysiological studies of the pelvic floor to appraise anorectal dysfunction in patients with multiple sclerosis]

INTRODUCTION

Patients with multiple sclerosis (MS) frequently develop anorectal dysfunction. The neuromuscular structures of the pelvic floor and the mechanisms of voluntary control over defecation can be compromised by the patchy lesions of MS or secondary to the patient's disability. The involvement of multiple factors limits understanding of the pathophysiology of anorectal dysfunction in MS. Specific neurophysiological tests assess the functionality of the elements of the central and peripheral nervous system involved in anorectal dysfunction.

AIM

To propose a diagnostic protocol of standardised neurophysiological studies of the pelvic floor in order to characterise the pathophysiology of anorectal dysfunction in patients with MS.

PATIENTS AND METHODS

The following studies were conducted on 16 patients with defined MS and who met criteria for constipation or faecal incontinence: external anal sphincter electromyography (EAS-EMG), somatosensory evoked potentials (SSEP) of the internal pudendal nerve, recording of ano-sacral reflexes and pudendal nerve neurography.

RESULTS

The clinical and neurophysiological characteristics were heterogeneous. Nine patients presented constipation; two had isolated faecal incontinence; and five, a combination of both. Abolition or delay in the latency of the SSEP was the most frequent finding (n = 12), followed by the detection of paradoxical contraction (n = 11) and deficient recruitment (n = 8) in the EAS-EMG.

CONCLUSIONS

The correct interpretation of each available neurophysiological test and the correlation of the findings as a whole enable us to understand the pathophysiology of anorectal dysfunction. The implementation of a protocol for neuro-physiological studies of the pelvic floor makes it possible to adjust the diagnosis by identifying the central or peripheral nervous lesion determining anorectal dysfunction in patients with MS.

Efficacy of Adjuvant 5-Fluorouracil Therapy for Patients with EMAST-Positive Stage II/III Colorectal Cancer

Elevated Microsatellite Alterations at Selected Tetranucleotide repeats (EMAST) is a genetic signature found in up to 60% of colorectal cancers (CRCs) that is caused by somatic dysfunction of the DNA mismatch repair (MMR) protein hMSH3. We have previously shown in vitro that recognition of 5-fluorouracil (5-FU) within DNA and subsequent cytotoxicity was most effective when both hMutSα (hMSH2-hMSH6 heterodimer) and hMutSβ (hMSH2-hMSH3 heterodimer) MMR complexes were present, compared to hMutSα > hMutSβ alone. We tested if patients with EMAST CRCs (hMutSβ defective) had diminished response to adjuvant 5-FU chemotherapy, paralleling in vitro findings. We analyzed 230 patients with stage II/III sporadic colorectal cancers for which we had 5-FU treatment and survival data. Archival DNA was analyzed for EMAST (>2 of 5 markers mutated among UT5037, D8S321, D9S242, D20S82, D20S85 tetranucleotide loci). Kaplan-Meier survival curves were generated and multivariate analysis was used to determine contribution to risk. We identified 102 (44%) EMAST cancers. Ninety-four patients (41%) received adjuvant 5-FU chemotherapy, and median follow-up for all patients was 51 months. Patients with EMAST CRCs demonstrated improved survival with adjuvant 5FU to the same extent as patients with non-EMAST CRCs (P<0.05). We observed no difference in survival between patients with stage II/III EMAST and non-EMAST cancers (P = 0.36). There is improved survival for stage II/III CRC patients after adjuvant 5-FU-based chemotherapy regardless of EMAST status. The loss of contribution of hMSH3 for 5-FU cytotoxicity may not adversely affect patient outcome, contrasting patients whose tumors completely lack DNA MMR function (MSI-H).

Prevalence of somatic mutl homolog 1 promoter hypermethylation in Lynch syndrome colorectal cancer

BACKGROUND

Colorectal cancers (CRCs) that have microsatellite instability (MSI) and mutL homolog 1 (MLH1) immunoloss are observed in 3 clinical scenarios: Lynch syndrome (LS), sporadic MSI CRC, and Lynch-like syndrome (LLS). v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) mutational analysis is used to differentiate LS from sporadic MSI CRC. The role of MLH1 promoter methylation status for the differential diagnosis of these clinical forms is not well established. The objectives of this study were: 1) to analyze MLH1 promoter methylation in MLH1-deficient CRCs by pyrosequencing, and 2) to assess its role in the differential diagnosis of MLH1-deficient CRCs.

METHODS

In total, 165 CRCs were analyzed, including LS (n = 19), MSI BRAF-mutated CRC (n = 37), MSI BRAF wild-type CRC (n = 60), and a control group of CRCs without MSI (microsatellite stable [MSS] CRC; n = 49). MLH1 promoter methylation status was analyzed by pyrosequencing, and the ability of different strategies to identify LS was assessed.

RESULTS

The average ± standard deviation methylation in LS (9% ± 7%) was significantly lower than that in MSI BRAF-mutated CRC (42% ± 17%; P < .001) and in MSI BRAF wild-type CRC (25% ± 19%; P = .002). Somatic MLH1 hypermethylation was detected in 3 patients (15.8%) with LS, in 34 patients (91.9%) with MSI BRAF-mutated CRC, and in 37 patients (61.7%) with MSI BRAF wild-type tumors. Patients with MSI BRAF wild-type, unmethylated tumors (ie, LLS) had a stronger family history of CRC than those who had tumors with MLH1 methylation (P < .05). The sensitivity for ruling out LS was 100% for BRAF analysis, 84.2% for MLH1 methylation analysis, and 84.2% for the combination of both analyses.

CONCLUSIONS

Somatic MLH1 promoter methylation occurs in up to 15% of LS CRCs. Somatic BRAF analysis is the most sensitive strategy for ruling out LS. Patients who have CRCs with loss of MLH1 protein expression and neither BRAF mutation nor MLH1 methylation resemble patients with LS.

Prevalence of MLH1 constitutional epimutations as a cause of Lynch syndrome in unselected versus selected consecutive series of patients with colorectal cancer

BACKGROUND

The prevalence of MLH1 constitutional epimutations in the general population is unknown. We sought to analyse the prevalence of MLH1 constitutional epimutations in unselected and selected series of patients with colorectal cancer (CRC).

METHODS

Patients with diagnoses of CRC (n=2123) were included in the unselected group. For comparison, a group of 847 selected patients with CRC who fulfilled the revised Bethesda guidelines (rBG) were also included. Somatic and constitutional MLH1 methylation was assayed via methylation-specific multiplex ligation-dependent probe amplification of cases lacking MLH1 expression. Germline alterations in mismatch-repair (MMR) genes were assessed via Sanger sequencing and methylation-specific multiplex ligation-dependent probe amplification.

RESULTS

Loss of MLH1 expression occurred in 5.5% of the unselected series and 12.5% of the selected series (p<0.0001). No constitutional epimutations in MLH1 were detected in the unselected population (0/62); five cases from the selected series were positive for MLH1 epimutations (15.6%, 5/32; p=0.004).

CONCLUSIONS

Our results suggest a negligible prevalence of MLH1 constitutional epimutations in unselected cases of CRC. Therefore, MLH1 constitutional epimutation analysis should be conducted only for patients who fulfil the rBG and who lack MLH1 expression with methylated MLH1.

Guidelines for diagnosis, staging and treatment of metastatic colorectal cancer by Grupo Español Multidisciplinar en Cancer Digestivo (GEMCAD)

Abstract 

Advances in the care of patients with metastatic colorectal cancer arise from well-designed clinical trials. In the present document we address specific challenges in the design of clinical trials for metastatic colorectal cancer regarding staging and standard of care according to prognosis, as well as some relevant methodological issues.

Identification of risk loci for Crohn's disease phenotypes using a genome-wide association study

BACKGROUND & AIMS

Crohn's disease is a highly heterogeneous inflammatory bowel disease comprising multiple clinical phenotypes. Genome-wide association studies (GWASs) have associated a large number of loci with disease risk but have not associated any specific genetic variants with clinical phenotypes. We performed a GWAS of clinical phenotypes in Crohn's disease.

METHODS

We genotyped 576,818 single-nucleotide polymorphisms in a well-characterized cohort of 1090 Crohn's disease patients of European ancestry. We assessed their association with 17 phenotypes of Crohn's disease (based on disease location, disease behavior, disease course, age at onset, and extraintestinal manifestations). A total of 57 markers with strong associations to Crohn's disease phenotypes (P < 2 × 10(-4)) were subsequently analyzed in an independent replication cohort of 1296 patients of European ancestry.

RESULTS

We replicated the association of 4 loci with different Crohn's disease phenotypes. Variants in MAGI1, CLCA2, 2q24.1, and LY75 loci were associated with a complicated stricturing disease course (Pcombined = 2.01 × 10(-8)), disease location (Pcombined = 1.3 × 10(-6)), mild disease course (Pcombined = 5.94 × 10(-7)), and erythema nodosum (Pcombined = 2.27 × 10(-6)), respectively.

CONCLUSIONS

In a GWAS, we associated 4 loci with clinical phenotypes of Crohn's disease. These findings indicate a genetic basis for the clinical heterogeneity observed for this inflammatory bowel disease.

Rate of detection of advanced neoplasms in proximal colon by simulated sigmoidoscopy vs fecal immunochemical tests

BACKGROUND & AIMS

We compared the ability of biennial fecal immunochemical testing (FIT) and one-time sigmoidoscopy to detect colon side-specific advanced neoplasms in a population-based, multicenter, nationwide, randomized controlled trial.

METHODS

We identified asymptomatic men and women, 50-69 years old, through community health registries and randomly assigned them to groups that received a single colonoscopy examination or biennial FIT. Sigmoidoscopy yield was simulated from results obtained from the colonoscopy group, according to the criteria proposed in the UK Flexible Sigmoidoscopy Trial for colonoscopy referral. Patients who underwent FIT and were found to have ≥75 ng hemoglobin/mL were referred for colonoscopy. Data were analyzed from 5059 subjects in the colonoscopy group and 10,507 in the FIT group. The main outcome was rate of detection of any advanced neoplasm proximal to the splenic flexure.

RESULTS

Advanced neoplasms were detected in 317 subjects (6.3%) in the sigmoidoscopy simulation group compared with 288 (2.7%) in the FIT group (odds ratio for sigmoidoscopy, 2.29; 95% confidence interval, 1.93-2.70; P = .0001). Sigmoidoscopy also detected advanced distal neoplasia in a higher percentage of patients than FIT (odds ratio, 2.61; 95% confidence interval, 2.20-3.10; P = .0001). The methods did not differ significantly in identifying patients with advanced proximal neoplasms (odds ratio, 1.17; 95% confidence interval, 0.78-1.76; P = .44). This was probably due to the lower performance of both strategies in detecting patients with proximal lesions (sigmoidoscopy detected these in 19.1% of patients and FIT in 14.9% of patients) vs distal ones (sigmoidoscopy detected these in 86.8% of patients and FIT in 33.5% of patients). Sigmoidoscopy, but not FIT, detected proximal lesions in lower percentages of women (especially those 50-59 years old) than men.

CONCLUSIONS

Sigmoidoscopy and FIT have similar limitations in detecting advanced proximal neoplasms, which depend on patients' characteristics; sigmoidoscopy underperforms for women 50-59 years old. Screening strategies should be designed on the basis of target population to increase effectiveness and cost-effectiveness. ClinicalTrials.gov number: NCT00906997.

Risk of colectomy in patients with ulcerative colitis under thiopurine treatment

BACKGROUND AND AIMS

Little is known about the risk factors of colectomy in patients with ulcerative colitis (UC) under thiopurine treatment. The aim of the study was to determine the prevalence and the predictive risk factors of colectomy in an extensive cohort of patients with UC treated with thiopurines in Spain.

METHODS

Among 5753 UC patients, we identified those diagnosed between 1980 and 2009 and treated with azathioprine or mercaptopurine (AZA/MP). We analyzed the age at diagnosis, familial history of IBD, extraintestinal manifestations (EIMs), disease extent, smoking status and treatment requirements (AZA/MP, cyclosporine (CsA) or anti-TNFα). Colectomies for dysplasia or cancer were excluded. Survival analysis and Cox proportional hazard regression were performed. Results were reported as hazard ratios (HR) with 95% CI.

RESULTS

Among the 1334 cases included, 119 patients (8.9%) required colectomy after a median time of 26 months (IQR 12-42) after AZA/MP initiation. Independent predictors of colectomy were: Extensive UC (HR 1.7, 95% CI: 1.1-2.6), EIMs (HR 1.5, 95% CI: 1.0-2.4), need for antiTNFα (HR 2.3, 95% CI: 1.5-3.4) and need for CsA (HR 2.4, 95% CI: 1.6-3.7). Patients requiring early introduction of AZA/MP had an increased risk of colectomy with a HR of 4.9 (95% CI: 3.2-7.8) when AZA/MP started in the first 33 months after UC diagnosis.

CONCLUSIONS

Nearly one-tenth of patients with UC under thiopurines require colectomy. Extensive UC, EIMs, need for CsA or anti-TNFα ever and an early need for AZA/MP treatment were associated with a higher risk of colectomy. These risk factors of colectomy could help to stratify risk in further controlled studies in UC.

Risk stratification for advanced colorectal neoplasia according to fecal hemoglobin concentration in a colorectal cancer screening program

BACKGROUND & AIMS

The latest generation of fecal immunochemical tests (FIT) allows for quantitation of hemoglobin in feces, allowing for selection of optimal cut-off concentrations. We investigated whether individuals with positive results from quantitative FITs, in combination with other factors, could be identified as being at greatest risk for advanced colorectal neoplasia.

METHODS

In a retrospective study, we analyzed data from a consecutive series of 3109 participants with positive results from FITs (≥20 μg/g of feces) included in the first round of the Barcelona colorectal cancer screening program, from December 2009 through February 2012. All participants underwent colonoscopy and were assigned to groups with any advanced colorectal neoplasia or with nonadvanced colorectal neoplasia (but with another diagnosis or normal examination findings).

RESULTS

Median fecal hemoglobin concentrations were significantly higher in participants with advanced colorectal neoplasia (105 μg/g; interquartile range, 38-288 μg/g) compared with participants with nonadvanced colorectal neoplasia (47 μg/g; interquartile range, 23-119 μg/g) (P < .001). Positive predictive values for advanced colorectal neoplasia, determined using arbitrary fecal hemoglobin concentrations, differed with sex and age. Multivariate logistic regression analysis identified sex (men: odds ratio [OR], 2.07; 95% confidence interval, 1.78-2.41), age (60-69 y: OR, 1.24; 95% confidence interval, 1.07-1.44), and fecal hemoglobin concentration (>177 μg/g: OR, 3.80; 95% confidence interval, 3.07-4.71) as independent predictive factors for advanced colorectal neoplasia. Combining these factors, we identified 16 risk categories associated with different probabilities of identifying advanced colorectal neoplasia. Risk for advanced colorectal neoplasia increased 11.46-fold among individuals in the highest category compared with the lowest category; positive predictive values ranged from 21.3% to 75.6%.

CONCLUSIONS

Fecal hemoglobin concentration, in addition to sex and age, in individuals with positive results from FITs can be used to stratify probability for the detection of advanced colorectal neoplasia. These factors should be used to prioritize individuals for colonoscopy examination.

Participation and detection rates by age and sex for colonoscopy versus fecal immunochemical testing in colorectal cancer screening

PURPOSE

To compare two strategies for colorectal cancer screening: one-time colonoscopy versus fecal immunochemical testing (FIT) (and colonoscopy for positive) every 2 years, in order to determine which strategy provides the highest participation and detection rates in groups of sex and age.

METHODS

This analysis was performed with data from the first screening round within the COLONPREV study, a population-based, multicenter, nationwide trial carried out in Spain. Several logistic regression models were applied to identify the influence of the screening test on participation rates and detection of proximal and distal neoplasms, as well to identify the influence of age and sex: women aged 50-59 years, women aged 60-69 years, men aged 50-59 years, and men aged 60-69 years.

RESULTS

Participation was higher in women than in men, especially among women aged 50-59 years (25.91 % for colonoscopy and 35.81 % for FIT). Crossover from colonoscopy to FIT was higher among women than men, especially among those aged 60-69 years (30.37 %). In general, detection of any neoplasm and advanced adenoma was higher with colonoscopy than with FIT, but no significant differences were found between the two strategies for colorectal cancer detection. Detection of advanced adenoma in both arms was lower in women [specifically in women aged 50-59 years (OR 0.31; 95 % CI 0.25-0.38) than in men aged 60-69 years]. Women aged 50-59 years in the colonoscopy arm had a higher probability of detection of advanced adenoma (OR 4.49; 95 % CI 3.18-6.35), as well as of detection of neoplasms in proximal and distal locations (proximal OR 19.34; 95 % CI 12.07-31.00; distal OR 11.04; 95 % CI 8.13-15.01) than women of the same age in the FIT arm. These differences were also observed in the remaining groups but to a lesser extent.

CONCLUSION

Women were more likely to participate in a FIT-based strategy, especially those aged 50-59 years. The likelihood of detection of any neoplasm was higher in the colonoscopy arm for all the population groups studied, especially in women aged 50-59 years. Distinct population groups should be informed of the benefits of each screening strategy so that they may take informed decisions.

A genome-wide association study on copy-number variation identifies a 11q11 loss as a candidate susceptibility variant for colorectal cancer

Colorectal cancer (CRC) is a complex disease, and therefore its development is determined by the combination of both environmental factors and genetic variants. Although genome-wide association studies (GWAS) of SNP variation have conveniently identified 20 genetic variants so far, a significant proportion of the observed heritability is yet to be explained. Common copy-number variants (CNVs) are one of the most important genomic sources of variability, and hence a potential source to explain part of this missing genetic fraction. Therefore, we have performed a GWAS on CNVs to explore the relationship between common structural variation and CRC development. Phase 1 of the GWAS consisted of 881 cases and 667 controls from a Spanish cohort. Copy-number status was validated by quantitative PCR for each of those common CNVs potentially associated with CRC in phase I. Subsequently, SNPs were chosen as proxies for the validated CNVs for phase II replication (1,342 Spanish cases and 1,874 Spanish controls). Four common CNVs were found to be associated with CRC and were further replicated in Phase II. Finally, we found that SNP rs1944682, tagging a 11q11 CNV, was nominally associated with CRC susceptibility (p value = 0.039; OR = 1.122). This locus has been previously related to extreme obesity phenotypes, which could suggest a relationship between body weight and CRC susceptibility.

The MLH1 c.1852_1853delinsGC (p.K618A) variant in colorectal cancer: genetic association study in 18,723 individuals

Colorectal cancer is one of the most frequent neoplasms and an important cause of mortality in the developed world. Mendelian syndromes account for about 5% of the total burden of CRC, being Lynch syndrome and familial adenomatous polyposis the most common forms. Lynch syndrome tumors develop mainly as a consequence of defective DNA mismatch repair associated with germline mutations in MLH1, MSH2, MSH6 and PMS2. A significant proportion of variants identified by screening these genes correspond to missense or noncoding changes without a clear pathogenic consequence, and they are designated as “variants of uncertain significance”, being the c.1852_1853delinsGC (p.K618A) variant in the MLH1 gene a clear example. The implication of this variant as a low-penetrance risk variant for CRC was assessed in the present study by performing a case-control study within a large cohort from the COGENT consortium-COST Action BM1206 including 18,723 individuals (8,055 colorectal cancer cases and 10,668 controls) and a case-only genotype-phenotype correlation with several clinical and pathological characteristics restricted to the Epicolon cohort. Our results showed no involvement of this variant as a low-penetrance variant for colorectal cancer genetic susceptibility and no association with any clinical and pathological characteristics including family history for this neoplasm or Lynch syndrome.

Multiple sporadic colorectal cancers display a unique methylation phenotype

Epigenetics are thought to play a major role in the carcinogenesis of multiple sporadic colorectal cancers (CRC). Previous studies have suggested concordant DNA hypermethylation between tumor pairs. However, only a few methylation markers have been analyzed. This study was aimed at describing the epigenetic signature of multiple CRC using a genome-scale DNA methylation profiling. We analyzed 12 patients with synchronous CRC and 29 age-, sex-, and tumor location-paired patients with solitary tumors from the EPICOLON II cohort. DNA methylation profiling was performed using the Illumina Infinium HM27 DNA methylation assay. The most significant results were validated by Methylight. Tumors samples were also analyzed for the CpG Island Methylator Phenotype (CIMP); KRAS and BRAF mutations and mismatch repair deficiency status. Functional annotation clustering was performed. We identified 102 CpG sites that showed significant DNA hypermethylation in multiple tumors with respect to the solitary counterparts (difference in β value ≥0.1). Methylight assays validated the results for 4 selected genes (p = 0.0002). Eight out of 12(66.6%) multiple tumors were classified as CIMP-high, as compared to 5 out of 29(17.2%) solitary tumors (p = 0.004). Interestingly, 76 out of the 102 (74.5%) hypermethylated CpG sites found in multiple tumors were also seen in CIMP-high tumors. Functional analysis of hypermethylated genes found in multiple tumors showed enrichment of genes involved in different tumorigenic functions. In conclusion, multiple CRC are associated with a distinct methylation phenotype, with a close association between tumor multiplicity and CIMP-high. Our results may be important to unravel the underlying mechanism of tumor multiplicity.

Delphi consensus statement: Quality Indicators for Inflammatory Bowel Disease Comprehensive Care Units

BACKGROUND AND AIMS

While it is commonly accepted that Inflammatory bowel disease (IBD) Comprehensive Care Units (ICCUs) facilitate the delivery of quality care to Crohn's disease and ulcerative colitis patients, it remains unclear how an ICCU should be defined or evaluated. The aim of the present study was to develop a comprehensive set of Quality Indicators (QIs) of structure, process, and outcomes for defining and evaluating an ICCU.

METHODS

A Delphi consensus-based approach with a standardized three-step process was used to identify a core set of QIs. The process included an exhaustive search using complementary approaches to identify potential QIs, and two Delphi voting rounds to select the QIs defining the core requirements for an ICCU.

RESULTS

The consensus selected a core set of 56 QIs (12 structure, 20 process and 24 outcome). Structure and process QIs highlighted the need for multidisciplinary management and continuity of care. The minimal IBD team should include an IBD nurse, gastroenterologists, radiologists, surgeons, endoscopists and stoma management specialists. ICCUs should be able to provide both outpatient and inpatient care and admission should not break the continuity of care. Outcome QIs focused on the adequate prophylaxis of disease complication and drug adverse events, the need to monitor appropriateness of treatment and the need to reinforce patient autonomy by providing adequate information and facilitating the patients' participation in their own care.

CONCLUSIONS

The present Delphi consensus identified a set of core QIs that may be useful for evaluating and certifying ICCUs.

New genes emerging for colorectal cancer predisposition

Colorectal cancer (CRC) is one of the most frequent neoplasms and an important cause of mortality in the developed world. This cancer is caused by both genetic and environmental factors although 35% of the variation in CRC susceptibility involves inherited genetic differences. Mendelian syndromes account for about 5% of the total burden of CRC, with Lynch syndrome and familial adenomatous polyposis the most common forms. Excluding hereditary forms, there is an important fraction of CRC cases that present familial aggregation for the disease with an unknown germline genetic cause. CRC can be also considered as a complex disease taking into account the common disease-commom variant hypothesis with a polygenic model of inheritance where the genetic components of common complex diseases correspond mostly to variants of low/moderate effect. So far, 30 common, low-penetrance susceptibility variants have been identified for CRC. Recently, new sequencing technologies including exome- and whole-genome sequencing have permitted to add a new approach to facilitate the identification of new genes responsible for human disease predisposition. By using whole-genome sequencing, germline mutations in the POLE and POLD1 genes have been found to be responsible for a new form of CRC genetic predisposition called polymerase proofreading-associated polyposis.

Accuracy of magnetic resonance enterography in assessing response to therapy and mucosal healing in patients with Crohn's disease

BACKGROUND & AIMS

We assessed the accuracy of magnetic resonance enterography (MRE) in monitoring response to therapy in patients with Crohn's disease (CD) using ileocolonoscopy as a reference standard.

METHODS

We performed a prospective multicenter study of 48 patients with active CD and ulcers in at least one ileocolonic segment. All patients underwent ileocolonoscopy and MRE at baseline and 12 weeks after completing treatment with corticosteroids (CS) or anti-tumor necrosis factor agents. Disease activity was quantified using Crohn's Disease Endoscopic Index of Severity (CDEIS) and Magnetic Resonance Index of Activity (MaRIA). The primary analysis was to determine the accuracy of MRE in identification of healing, defined as the disappearance of ulcers in endoscopy examination. Additional analyses established the accuracy of MRE in determining endoscopic remission (a CDEIS score <3.5) and change in severity based on consideration of all segments.

RESULTS

MRE determined ulcer healing with 90% accuracy and endoscopic remission with 83% accuracy. The mean CDEIS and MaRIA scores significantly changed at week 12 in segments with ulcer healing, based on endoscopic examination (CDEIS: 21.28 ± 9.10 at baseline vs 2.73 ± 4.12 at 12 weeks; P < .001 and MaRIA: 18.86 ± 9.50 at baseline vs 8.73 ± 5.88 at 12 weeks; P < .001). The MaRIA score accurately detected changes in lesion severity (Guyatt score: 1.2 and standardized effect size: 1.07). MRE was as reliable as endoscopy in assessing healing; no significant changes in CDEIS or MaRIA scores were observed in segments with persistent ulcers, based on endoscopic examination (CDEIS: 26.43 ± 9.06 at baseline vs 20.77 ± 9.13 at 12 weeks; P = .18 and MaRIA: 22.13 ± 8.42 at baseline vs 20.77 ± 9.17 at 12 weeks; P = .42). The magnitude of change in CDEIS scores correlated with those in MaRIA scores (r = 0.51; P < .001).

CONCLUSIONS

MRE evaluates ulcer healing with a high level of accuracy when ileocolonoscopy is used as the reference standard. The MaRIA is a valid, responsive, and reliable index assessing response to therapy in patients with CD.

Outcome in obscure gastrointestinal bleeding after capsule endoscopy

AIM: To investigate the clinical impact of capsule endoscopy (CE) after an obscure gastrointestinal bleeding (OGIB) episode, focusing on diagnostic work-up, follow-up and predictive factors of rebleeding.

METHODS: Patients who were referred to Hospital del Mar (Barcelona, Spain) between 2007 and 2009 for OGIB who underwent a CE were retrospectively analyzed. Demographic data, current treatment with non-steroid anti-inflammtory drugs or anticoagulant drugs, hemoglobin levels, transfusion requirements, previous diagnostic tests for the bleeding episode, as well as CE findings (significant or non-significant), work-up and patient outcomes were analyzed from electronic charts. Variables were compared by χ² analysis and Student t test. Risk factors of rebleeding were assessed by Log-rank test, Kaplan-Meier curves and Cox regression model.

RESULTS: There were 105 patients [45.7% women, median age of 72 years old (interquartile range 56-79)] and a median follow-up of 326 d (interquartile range 123-641) included in this study. The overall diagnostic yield of CE was 58.1% (55.2% and 63.2%, for patients with occult OGIB and overt OGIB, respectively). In 73 patients (69.5%), OGIB was resolved. Multivariate analysis showed that hemoglobin levels lower than 8 g/dL at diagnosis [hazard ratios (HR) = 2.7, 95%CI: 1.9-6.3], patients aged 70 years and above (HR = 2.1, 95%CI: 1.2-6.1) and significant findings in CE (HR = 2.4, 95%CI: 1.1-5.8) were independent predictors of rebleeding.

CONCLUSION: One third of the patients presented with rebleeding after CE; risk factors were hemoglobin levels < 8 g/dL, age ≥ 70 years or the presence of significant lesions.

[Treatment of colorectal cancer with unresectable metastasis with chemotherapy without primary tumor resection: analysis of tumor-related complications]

INTRODUCTION

Although the conventional treatment of patients with stage iv colorectal cancer involves resection of the primary tumor followed by chemotherapy, several studies suggest that in patients with few symptoms the first and only treatment should be chemotherapy. The objective of this study is to analyze the complications related to the primary tumor in a series of patients with unresectable metastatic colorectal cancer treated with chemotherapy without surgery.

MATERIAL AND METHODS

Retrospective descriptive study. The study included all patients with unresectable metastatic colorectal cancer treated with chemotherapy without resection of the primary tumor (January 2007-February 2011).

RESULTS

The mean age of the 61 patients analyzed was 67±13 years and the performance status was 0-1 in 53 (87%). Twenty (33%) patients developed complications during follow-up. The most common complication was intestinal obstruction in 15 (25%) patients followed by perforation. Complications required surgery in 6 (10%) cases. We did not find differences in patient characteristics between those who had a complication and those without, although the complication rate in patients with a colonic stent (53%) was twice that of other patients (26%).

CONCLUSIONS

Chemotherapy without surgery is a good option in most patients with unresectable metastatic colorectal cancer. However, although the percentage of patients requiring surgery is low, the total number of complications related to the primary tumor is not negligible. Studies are needed to identify those patients in whom a prophylactic colectomy could be indicated.

A genome-wide association study on a southern European population identifies a new Crohn's disease susceptibility locus at RBX1-EP300

OBJECTIVE

Genome-wide association studies (GWAS) have identified multiple risk loci for Crohn's disease (CD). However, the cumulative risk exerted by these loci is low, and the likelihood that additional, as-yet undiscovered loci contribute to the risk of CD is very high. We performed a GWAS on a southern European population to identify new CD risk loci.

DESIGN

We genotyped 620 901 genome markers on 1341 CD patients and 1518 controls from Spain. The top association signals representing new candidate risk loci were subsequently analysed in an independent replication cohort of 1365 CD patients and 1396 controls.

RESULTS

We identified a genome-wide significant association on chromosome 22q13.2 in the intergenic region between the RBX1 and EP300 genes (single nucleotide polymorphism rs4820425, OR 1.27, 95% CI 1.17 to 1.38, p=3.42E-8). We also found suggestive evidence for the association of the IFNGR2 (21q22.11), FOXP2 (7q31), MACROD2 (20p12.1) and AIF1 (6p21.3) loci with CD risk.

CONCLUSIONS

In this GWAS performed on a southern European cohort, we have identified a new risk locus for CD between RBX1 and EP300. This study demonstrates that using populations of different ancestry is a useful strategy to identify new risk loci for CD.

Multidetector computed tomography in life-threatening hemoptysis

Life-threatening hemoptysis is a severe condition that requires rapid diagnosis and treatment. One of the treatments of choice is embolization. The initial assessment aims to locate the origin and cause of bleeding. The technological advance of the development of multidetector computed tomography (MDCT) has changed the management of patients with life-threatening hemoptysis. MDCT angiography makes it possible to evaluate the cause of bleeding and locate the vessels involved both rapidly and noninvasively; it is particularly useful for detecting ectopic bronchial arteries, nonbronchial systemic arteries, and pulmonary pseudoaneurysms. Performing MDCT angiography systematically before embolization enables better treatment planning. In this article, we review the pathophysiology and causes of life-threatening hemoptysis (including cryptogenic hemoptysis) and the MDCT angiography technique, and we review how to systematically evaluate the images (lung parenchyma, airways, and vascular structures).

Relationship of colonoscopy-detected serrated polyps with synchronous advanced neoplasia in average-risk individuals

BACKGROUND

Serrated cancers account for 10% to 20% of all colorectal cancers (CRC) and more than 30% of interval cancers. The presence of proximal serrated polyps and large (≥10 mm) serrated polyps (LSP) has been correlated with colorectal neoplasia.

OBJECTIVE

To evaluate the prevalence of serrated polyps and their association with synchronous advanced neoplasia in a cohort of average-risk population and to assess the efficacy of one-time colonoscopy and a biennial fecal immunochemical test for reducing CRC-related mortality. This study focused on the sample of 5059 individuals belonging to the colonoscopy arm.

DESIGN

Multicenter, randomized, controlled trial.

SETTING

The ColonPrev study, a population-based, multicenter, nationwide, randomized, controlled trial.

PATIENTS

A total of 5059 asymptomatic men and women aged 50 to 69 years.

INTERVENTION

Colonoscopy.

MAIN OUTCOME MEASUREMENTS

Prevalence of serrated polyps and their association with synchronous advanced neoplasia.

RESULTS

Advanced neoplasia was detected in 520 individuals (10.3%) (CRC was detected in 27 [0.5%] and advanced adenomas in 493 [9.7%]). Serrated polyps were found in 1054 individuals (20.8%). A total of 329 individuals (6.5%) had proximal serrated polyps, and 90 (1.8%) had LSPs. Proximal serrated polyps or LSPs were associated with male sex (odds ratio [OR] 2.08, 95% confidence interval [CI], 1.76-4.45 and OR 1.65, 95% CI, 1.31-2.07, respectively). Also, LSPs were associated with advanced neoplasia (OR 2.49, 95% CI, 1.47-4.198), regardless of their proximal (OR 4.15, 95% CI, 1.69-10.15) or distal (OR 2.61, 95% CI, 1.48-4.58) locations. When we analyzed subtypes of serrated polyps, proximal hyperplasic polyps were related to advanced neoplasia (OR 1.61, 95% CI, 1.13-2.28), although no correlation with the location of the advanced neoplasia was observed.

LIMITATIONS

Pathology criteria for the diagnosis of serrated polyps were not centrally reviewed. The morphology of the hyperplasic polyps (protruded or flat) was not recorded. Finally, because of the characteristics of a population-based study carried out in average-risk patients, the proportion of patients with CRC was relatively small.

CONCLUSION

LSPs, but not proximal serrated polyps, are associated with the presence of synchronous advanced neoplasia. Further studies are needed to determine the risk of proximal hyperplastic polyps.

Effect of aspirin and antiplatelet drugs on the outcome of the fecal immunochemical test

OBJECTIVE

To evaluate the effect of aspirin and nonaspirin antiplatelet agents (NAAAs) on the performance of the fecal immunochemical test (FIT).

PARTICIPANTS AND METHODS

We performed a post hoc analysis of results from a clinical trial that involved 28,696 asymptomatic average-risk men and women aged 50 to 69 years invited to participate in a colorectal cancer screening program with FIT between November 1, 2008, and June 31, 2011.

RESULTS

The test was returned by 6390 individuals (22.3%), of whom 5821 (91.1%) reported not using antiplatelet drugs (nonusers group) and 569 (8.9%) reported using these drugs at the time of testing (users group). The FIT result was positive in 48 of 569 users (8.4%) and 365 of 5821 nonusers (6.3%) (P=.05). A positive FIT result was found in 7.3% (28/384) of aspirin users, 7.1% (10/140) of NAAA users, and 22.2% (10/45) of those undergoing dual antiplatelet therapy (DAPT) (aspirin plus an NAAA). The DAPT subgroup had a significantly higher positive FIT rate than the nonuser group (odds ratio, 3.5; 95% CI, 1.7-7.3; P<.05). The positive predictive value (PPV) for advanced neoplasia (AN) in nonusers was 50.4% vs 50.0% in users (P = .40). The PPV for AN was 57.0% in aspirin users, 30.0% in NAAA users, and 50.0% in DAPT users, without statistically significant differences between the user and nonuser groups.

CONCLUSION

The use of DAPT increased the rate of positive FIT results. Use of aspirin, NAAAs, or both did not modify the PPV for AN in this population-based colorectal screening program.