Thyroidectomy for Euthyroid Patients with Hashimoto Disease and Persistent Symptoms: An Observational, Postrandomization Study

Background

Despite adequate hormone substitution in Hashimoto disease, some patients may have persistent symptoms with a possible autoimmune pathophysiology. A recent randomized trial (RCT) using patient-reported outcome measures as the primary endpoint showed benefit in total thyroidectomy, but at a cost of high complication rates.

Objective

To verify results from the RCT in an observational study including a wider range of patients and explore means of predicting who may benefit from such surgery.

Design

A total of 154 patients with Hashimoto disease, euthyroid with or without thyroid hormone substitution, and persistent Hashimoto-related symptoms were subjected to total thyroidectomy and followed for 18 months after surgery. The primary outcome was the General Health (GH) dimensional score in the Short Form-36 Health Survey (SF-36).

Results

Eighteen months after surgery, a clinically significant improvement in GH was seen, similar to the findings in the previous RCT. Anti-TPO antibody titers were markedly reduced after surgery, but preoperative titers or other preoperative parameters could not predict the outcome of surgery. Three (1.9%) of 154 patients experienced permanent unilateral recurrent nerve palsy and six (3.9%) experienced hypoparathyroidism after surgery.

Conclusions

Thyroidectomy had a beneficial symptom-reducing effect in euthyroid patients with Hashimoto disease and persistent symptoms. The pathophysiology of residual symptoms remains unclear, and surgical complication rates are high. If thyroidectomy is considered as a treatment option, it should be performed in dedicated centers with experienced endocrine surgeons and as part of further studies on persistent symptoms. This trial is registered with NCT-02319538.

Low-Dose Aspirin and Prevention of Colorectal Cancer: Evidence From a Nationwide Registry-Based Cohort in Norway

INTRODUCTION

To examine the association between low-dose aspirin use and risk of colorectal cancer (CRC).

METHODS

In this nationwide cohort study, we identified individuals aged 50 years or older residing for 6 months or more in Norway in 2004-2018 and obtained data from national registers on drug prescriptions, cancer occurrence, and sociodemographic factors. Multivariable Cox regression models were used to estimate the association between low-dose aspirin use and CRC risk. In addition, we calculated the number of CRC potentially averted by low-dose aspirin use.

RESULTS

We included 2,186,390 individuals. During the median follow-up of 10.9 years, 579,196 (26.5%) used low-dose aspirin, and 38,577 (1.8%) were diagnosed with CRC. Current use of aspirin vs never use was associated with lower CRC risk (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.84-0.90). The association was more pronounced for metastatic CRC (HR 0.79; 95% CI 0.74-0.84) than regionally advanced (HR 0.89; 95% CI 0.85-0.92) and localized CRC (HR 0.93; 95% CI 0.87-1.00; P heterogeneity = 0.001). A significant trend was found between duration of current use and CRC risk: HR 0.91 (95% CI 0.86-0.95) for <3 years, HR 0.85 (0.80-0.91) for ≥3 and <5 years, and HR 0.84 (0.80-0.88) for ≥5 years of use vs never use ( P trend < 0.001). For past use, HR were 0.89 (95% CI 0.84-0.94) for <3 years, 0.90 (0.83-0.99) for ≥3 and <5 years, and 0.98 (0.91-1.06) for ≥5 years since last use vs never use ( P -trend < 0.001). We estimated that aspirin use averted 1,073 cases of CRC (95% CI 818-1,338) in the study period.

DISCUSSION

In this nationwide cohort, use of low-dose aspirin was associated with a lower risk of CRC.

Effectiveness of Colonoscopy Screening vs Sigmoidoscopy Screening in Colorectal Cancer

Importance

Randomized clinical screening trials have shown that sigmoidoscopy screening reduces colorectal cancer (CRC) incidence and mortality. Colonoscopy has largely replaced sigmoidoscopy for CRC screening, but long-term results from randomized trials on colonoscopy screening are still lacking.

Objective

To estimate the additional screening benefit of colonoscopy compared with sigmoidoscopy.

Design, Setting, and Participants

This comparative effectiveness simulation study pooled data on 358 204 men and women randomly assigned to sigmoidoscopy screening or usual care in 4 randomized sigmoidoscopy screening trials conducted in Norway, Italy, the US, and UK with inclusion periods in the years 1993 to 2001. The primary analysis of the study was conducted from January 19 to December 30, 2021.

Intervention

Invitation to endoscopic screening.

Main Outcomes and Measures

Primary outcomes were CRC incidence and mortality. Using pooled 15-year follow-up data, colonoscopy screening effectiveness was estimated assuming that the efficacy of colonoscopy in the proximal colon was similar to that observed in the distal colon in the sigmoidoscopy screening trials. The simulation model was validated using data from Norwegian participants in a colonoscopy screening trial.

Results

This analysis included 358 204 individuals (181 971 women [51%]) aged 55 to 64 years at inclusion with a median follow-up time ranging from 15 to 17 years. Compared with usual care, colonoscopy prevented an estimated 50 (95% CI, 42-58) CRC cases per 100 000 person-years, corresponding to 30% incidence reduction (rate ratio, 0.70 [95% CI, 0.66-0.75]), and prevented an estimated 15 (95% CI, 11-19) CRC deaths per 100 000 person-years, corresponding to 32% mortality reduction (rate ratio, 0.68 [95% CI, 0.61-0.76]). The additional benefit of colonoscopy screening compared with sigmoidoscopy was 12 (95% CI, 10-14) fewer CRC cases and 4 (95% CI, 3-5) fewer CRC deaths per 100 000 person-years, corresponding to percentage point reductions of 6.9 (95% CI, 6.0-7.9) for CRC incidence and 7.6 (95% CI, 5.7-9.6) for CRC mortality. The number needed to switch from sigmoidoscopy to colonoscopy screening was 560 (95% CI, 486-661) to prevent 1 CRC case and 1611 (95% CI, 1275-2188) to prevent 1 CRC death.

Conclusions and Relevance

The findings of this comparative effectiveness study assessing long-term follow-up after CRC screening suggest that there was an additional preventive effect on CRC incidence and mortality associated with colonoscopy screening compared with sigmoidoscopy screening, but the additional preventive effect was less than what was achieved by introducing sigmoidoscopy screening where no screening existed. The results probably represent the upper limit of what may be achieved with colonoscopy screening compared with sigmoidoscopy screening.

Lifestyle changes in middle age and risk of cancer: evidence from the European Prospective Investigation into Cancer and Nutrition

In this study, we aimed to provide novel evidence on the impact of changing lifestyle habits on cancer risk. In the EPIC cohort, 295,865 middle-aged participants returned a lifestyle questionnaire at baseline and during follow-up. At both timepoints, we calculated a healthy lifestyle index (HLI) score based on cigarette smoking, alcohol consumption, body mass index and physical activity. HLI ranged from 0 (most unfavourable) to 16 (most favourable). We estimated the association between HLI change and risk of lifestyle-related cancers-including cancer of the breast, lung, colorectum, stomach, liver, cervix, oesophagus, bladder, and others-using Cox regression models. We reported hazard ratios (HR) with 95% confidence intervals (CI). Median time between the two questionnaires was 5.7 years, median age at follow-up questionnaire was 59 years. After the follow-up questionnaire, we observed 14,933 lifestyle-related cancers over a median follow-up of 7.8 years. Each unit increase in the HLI score was associated with 4% lower risk of lifestyle-related cancers (HR 0.96; 95%CI 0.95-0.97). Among participants in the top HLI third at baseline (HLI > 11), those in the bottom third at follow-up (HLI ≤ 9) had 21% higher risk of lifestyle-related cancers (HR 1.21; 95%CI 1.07-1.37) than those remaining in the top third. Among participants in the bottom HLI third at baseline, those in the top third at follow-up had 25% lower risk of lifestyle-related cancers (HR 0.75; 95%CI 0.65-0.86) than those remaining in the bottom third. These results indicate that lifestyle changes in middle age may have a significant impact on cancer risk.

Profiling small RNAs in fecal immunochemical tests: is it possible?

Fecal microRNAs represent promising molecules with potential clinical interest as non-invasive diagnostic and prognostic biomarkers. Colorectal cancer (CRC) screening based on the fecal immunochemical test (FIT) is an effective tool for prevention of cancer development. However, due to the poor sensitivity of FIT especially for premalignant lesions, there is a need for implementation of complementary tests. Improving the identification of individuals who would benefit from further investigation with colonoscopy using molecular analysis, such as miRNA profiling of FIT samples, would be ideal due to their widespread use. In the present study, we assessed the feasibility of applying small RNA sequencing to measure human miRNAs in FIT leftover buffer in samples from two European screening populations. We showed robust detection of miRNAs with profiles similar to those obtained from specimens sampled using the established protocol of RNA stabilizing buffers, or in long-term archived samples. Detected miRNAs exhibited differential abundances for CRC, advanced adenoma, and control samples that were consistent for FIT and RNA-stabilizing buffers. Interestingly, the sequencing data also allowed for concomitant evaluation of small RNA-based microbial profiles. We demonstrated that it is possible to explore the human miRNome in FIT leftover samples across populations and envision that the analysis of small RNA biomarkers can complement the FIT in large scale screening settings.

An efficient strategy for evaluating new non-invasive screening tests for colorectal cancer: the guiding principles

OBJECTIVE

New screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers.

DESIGN

A formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles.

RESULTS

Twelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test's ability to discriminate between CRC and non-cancer states (phase I), followed by prospective estimation of accuracy across the continuum of neoplastic lesions in neoplasia-enriched populations (phase II). If these show promise, a provisional test positivity threshold is set before evaluation in typical screening populations. Phase III prospective studies determine single round intention-to-screen programme outcomes and confirm the test positivity threshold. Phase IV studies involve evaluation over repeated screening rounds with monitoring for missed lesions. Phases III and IV findings will provide the real-world data required to model test impact on CRC mortality and incidence.

CONCLUSION

New non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact.

Association between use of low-dose aspirin and detection of colorectal polyps and cancer in a screening setting

BACKGROUND

The possible protective effect of aspirin on risk of colorectal cancer (CRC) is still highly debated.

METHODS

We used data from Bowel Cancer Screening in Norway, a trial randomizing individuals from general population, aged 50-74 years, to flexible sigmoidoscopy or faecal immunochemical test (FIT), to study the association between aspirin use and detection of CRC and two CRC precursors: adenomas and advanced serrated lesions (ASL). Prescriptions of low-dose aspirin were obtained from Norwegian prescription database. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Among 64,889 screening participants (24,159 sigmoidoscopy, 40,730 FIT), 314 (0.5%) had CRC, 6,208 (9.6%) adenoma and 659 (1.0%) ASL. Overall and short-term use (<3 years) of low-dose aspirin, versus no use, were not associated with any colorectal lesion. Long-term use (≥3 years) was associated with lower detection of CRC (overall OR 0.66, 95%CI 0.46-0.93; sigmoidoscopy: 0.56, 0.33-0.97; FIT: 0.72, 0.45-1.15), adenomas in sigmoidoscopy arm (overall OR 0.95, 95%CI 0.87-1.03; sigmoidoscopy: 0.89, 0.80-0.99; FIT: 1.03, 0.89-1.18), but not ASLs. We did not observe significant differences in the effect of aspirin according to the location of colorectal lesions.

CONCLUSION

Our results suggest that long-term use of aspirin might have a protective effect against adenomas and colorectal cancer, but not ASLs.

Changes in Lifestyle and Risk of Colorectal Cancer in the European Prospective Investigation Into Cancer and Nutrition

INTRODUCTION

We investigated the impact of changes in lifestyle habits on colorectal cancer (CRC) risk in a multicountry European cohort.

METHODS

We used baseline and follow-up questionnaire data from the European Prospective Investigation into Cancer cohort to assess changes in lifestyle habits and their associations with CRC development. We calculated a healthy lifestyle index (HLI) score based on smoking status, alcohol consumption, body mass index, and physical activity collected at the 2 time points. HLI ranged from 0 (most unfavorable) to 16 (most favorable). We estimated the association between HLI changes and CRC risk using Cox regression models and reported hazard ratios (HR) with 95% confidence intervals (CI).

RESULTS

Among 295,865 participants, 2,799 CRC cases were observed over a median of 7.8 years. The median time between questionnaires was 5.7 years. Each unit increase in HLI from the baseline to the follow-up assessment was associated with a statistically significant 3% lower CRC risk. Among participants in the top tertile at baseline (HLI > 11), those in the bottom tertile at follow-up (HLI ≤ 9) had a higher CRC risk (HR 1.34; 95% CI 1.02-1.75) than those remaining in the top tertile. Among individuals in the bottom tertile at baseline, those in the top tertile at follow-up had a lower risk (HR 0.77; 95% CI 0.59-1.00) than those remaining in the bottom tertile.

DISCUSSION

Improving adherence to a healthy lifestyle was inversely associated with CRC risk, while worsening adherence was positively associated with CRC risk. These results justify and support recommendations for healthy lifestyle changes and healthy lifestyle maintenance for CRC prevention.

Colonoscopy quality improvement after initial training: A cross-sectional study of intensive short-term training

Background and study aims High-quality is crucial for the effectiveness of colonoscopy and can be achieved by high-quality training and verified with assessment of key performance indicators (KPIs) for colonoscopy such as cecum intubation rate (CIR), adenoma detection rate (ADR) and adequate polyp resection. Typically, trainees achieve adequate CIR after 275 procedures, but little is known about learning curves for KPIs after initial training. Methods This cross-sectional study includes work-up colonoscopies after a positive screening test with fecal occult blood testing (FIT) or sigmoidoscopy, performed by either trainees after 300 training colonoscopies or by consultants. Outcome measures were KPIs. We assessed inter-endoscopist variation in trainees and learning curves for trainees as a group. We also compared KPIs for trainees and consultants as a group.  Results Data from 6,655 colonoscopies performed by 21 trainees and 921 colonoscopies performed by 17 consultants were included. Most trainees achieved target standards for main KPIs. With time, trainees shortened cecum intubation time and withdrawal time without decreasing their ADR, reduced the proportion of painful colonoscopies, and increased the adequate polyp resection rate (all P  < 0.01). Compared to consultants, trainees had higher CIR (97.7 % vs. 96.3 %, P  = 0.02), ADR after positive FIT (57.6 % vs. 50.3 %, P  < 0.01), and proximal ADR after sigmoidoscopy screening (41.1 % vs. 29.8 %; P  < 0.01), higher adequate polyp resection rate (94.9 % vs. 93.1 %, P  = 0.01) and fewer serious adverse events (0.65 % vs. 1.41 %, P  = 0.02). Conclusions Trainees performed high-quality colonoscopies and achieved international target standards. Several KPIs continuously improved after initial training. Trainees outperformed consultants on several KPIs.

Long-term follow-up of colorectal cancer screening attendees identifies differences in Phascolarctobacterium spp. using 16S rRNA and metagenome sequencing

Background

The microbiome has been implicated in the initiation and progression of colorectal cancer (CRC) in cross-sectional studies. However, there is a lack of studies using prospectively collected samples.

Methods

From the Norwegian Colorectal Cancer Prevention (NORCCAP) trial, we analyzed 144 archived fecal samples from participants who were diagnosed with CRC or high-risk adenoma (HRA) at screening and from participants who remained cancer-free during 17 years of follow-up. We performed 16S rRNA sequencing of all the samples and metagenome sequencing on a subset of 47 samples. Differences in taxonomy and gene content between outcome groups were assessed for alpha and beta diversity and differential abundance.

Results

Diversity and composition analyses showed no significant differences between CRC, HRA, and healthy controls. Phascolarctobacterium succinatutens was more abundant in CRC compared with healthy controls in both the 16S and metagenome data. The abundance of Bifidobacterium and Lachnospiraceae spp. was associated with time to CRC diagnosis.

Conclusion

Using a longitudinal study design, we identified three taxa as being potentially associated with CRC. These should be the focus of further studies of microbial changes occurring prior to CRC diagnosis.

Type and Severity of Mental Illness and Participation in Colorectal Cancer Screening

INTRODUCTION

The effectiveness of colorectal cancer screening programs depends on the participation rate. This study examined the association between type and severity of mental illness and colorectal cancer screening participation.

METHODS

Between 2012 and 2017, a total of 46,919 individuals were invited to sigmoidoscopy screening in Norway, and 70,019 were invited to fecal immunochemical testing. In 2022, logistic regression was used to evaluate the association between the use of antipsychotics, anxiolytics, hypnotics, and antidepressants in the year preceding the screening invitation and screening participation, adjusted for demographic and socioeconomic factors. Defined daily doses of individual drugs were used to assess dose‒response relationships.

RESULTS

Overall, 19.2% (24.8% of women, 13.4% of men) of all invitees used at least 1 psychotropic medication. Nonparticipation in the 2 arms combined was associated with the use of anxiolytics (60.7% in users vs 43.2% in nonusers; OR=1.53; 95% CI=1.45, 1.62) and antipsychotics (64.3% vs 43.8%; OR=1.41; 95% CI=1.30, 1.53) and increased with higher doses for both drugs. Hypnotics and antidepressants were only weakly associated with nonparticipation in higher doses. Participation rates were 57.3%, 52.3%, 42.9%, and 35.4% in those prescribed 0, 1, 2, and 3-4 classes of psychotropic medications, respectively. The associations between the use of psychotropic medications and nonparticipation were similar for the 2 screening tests.

CONCLUSIONS

These findings show significant disparities in colorectal cancer screening participation for individuals with mental illness, independent of the screening method. Moreover, screening participation varied depending on the type and severity of mental illness. Targeted interventions are warranted to ensure that people with mental illness are supported to access the benefits of colorectal cancer screening.

15-Year Benefits of Sigmoidoscopy Screening on Colorectal Cancer Incidence and Mortality : A Pooled Analysis of Randomized Trials

BACKGROUND

The effectiveness of screening for colorectal cancer (CRC) by sex and age in randomized trials is uncertain.

OBJECTIVE

To evaluate the 15-year effect of sigmoidoscopy screening on CRC incidence and mortality.

DESIGN

Pooled analysis of 4 large-scale randomized trials of sigmoidoscopy screening.

SETTING

Norway, the United States, the United Kingdom, and Italy.

PARTICIPANTS

Women and men aged 55 to 64 years at enrollment.

INTERVENTION

Sigmoidoscopy screening.

MEASUREMENTS

Primary end points were cumulative incidence rate ratio (IRR) and mortality rate ratio (MRR) and rate differences after 15 years of follow-up comparing screening versus usual care in intention-to-treat analyses. Stratified analyses were done by sex, cancer site, and age at screening.

RESULTS

Analyses comprised 274 952 persons (50.7% women), 137 493 in the screening and 137 459 in the usual care group. Screening attendance was 58% to 84%. After 15 years, the rate difference for CRC incidence was 0.51 cases (95% CI, 0.40 to 0.63 cases) per 100 persons and the IRR was 0.79 (CI, 0.75 to 0.83). The rate difference for CRC mortality was 0.13 deaths (CI, 0.07 to 0.19 deaths) per 100 persons, and the MRR was 0.80 (CI, 0.72 to 0.88). Women had less benefit from screening than men for CRC incidence (IRR for women, 0.84 [CI, 0.77 to 0.91]; IRR for men, 0.75 [CI, 0.70 to 0.81]; P = 0.032 for difference) and mortality (MRR for women, 0.91 [CI, 0.77 to 1.17]; MRR for men, 0.73 [CI, 0.64 to 0.83]; P = 0.025 for difference). There was no statistically significant difference in screening effect between persons aged 55 to 59 years and those aged 60 to 64 years.

LIMITATION

Data from the U.K. trial were less granular because of privacy regulations.

CONCLUSION

This pooled analysis of all large randomized trials of sigmoidoscopy screening demonstrates a significant and sustained effect of sigmoidoscopy on CRC incidence and mortality for 15 years.

PRIMARY FUNDING SOURCE

Health Fund of South-East Norway.

Effect of Colonoscopy Screening on Risks of Colorectal Cancer and Related Death

BACKGROUND

Although colonoscopy is widely used as a screening test to detect colorectal cancer, its effect on the risks of colorectal cancer and related death is unclear.

METHODS

We performed a pragmatic, randomized trial involving presumptively healthy men and women 55 to 64 years of age drawn from population registries in Poland, Norway, Sweden, and the Netherlands between 2009 and 2014. The participants were randomly assigned in a 1:2 ratio either to receive an invitation to undergo a single screening colonoscopy (the invited group) or to receive no invitation or screening (the usual-care group). The primary end points were the risks of colorectal cancer and related death, and the secondary end point was death from any cause.

RESULTS

Follow-up data were available for 84,585 participants in Poland, Norway, and Sweden - 28,220 in the invited group, 11,843 of whom (42.0%) underwent screening, and 56,365 in the usual-care group. A total of 15 participants had major bleeding after polyp removal. No perforations or screening-related deaths occurred within 30 days after colonoscopy. During a median follow-up of 10 years, 259 cases of colorectal cancer were diagnosed in the invited group as compared with 622 cases in the usual-care group. In intention-to-screen analyses, the risk of colorectal cancer at 10 years was 0.98% in the invited group and 1.20% in the usual-care group, a risk reduction of 18% (risk ratio, 0.82; 95% confidence interval [CI], 0.70 to 0.93). The risk of death from colorectal cancer was 0.28% in the invited group and 0.31% in the usual-care group (risk ratio, 0.90; 95% CI, 0.64 to 1.16). The number needed to invite to undergo screening to prevent one case of colorectal cancer was 455 (95% CI, 270 to 1429). The risk of death from any cause was 11.03% in the invited group and 11.04% in the usual-care group (risk ratio, 0.99; 95% CI, 0.96 to 1.04).

CONCLUSIONS

In this randomized trial, the risk of colorectal cancer at 10 years was lower among participants who were invited to undergo screening colonoscopy than among those who were assigned to no screening. (Funded by the Research Council of Norway and others; NordICC ClinicalTrials.gov number, NCT00883792.).

Complete polyp resection with cold snare versus hot snare polypectomy for polyps of 4-9 mm: a randomized controlled trial

BACKGROUND

Endoscopic screening with polypectomy reduces the incidence of colorectal cancer (CRC). Incomplete polyp removal may attenuate the effect of screening. This randomized trial compared cold snare polypectomy (CSP) with hot snare polypectomy (HSP) in terms of complete polyp resection.

METHODS

We included patients ≥ 40 years of age at eight hospitals in four countries who had at least one non-pedunculated polyp of 4-9 mm detected at colonoscopy. Patients were randomized 1:1 to CSP or HSP. Biopsies from the resection margins were obtained systematically after polypectomy in both groups. We hypothesized that CSP would be non-inferior to HSP, with a non-inferiority margin of 5 %. Logistic regression models were fitted to identify the factors explaining incomplete resection.

RESULTS

425 patients, with 601 polyps, randomized to either CSP or HSP were included in the analysis. Of 318 polyps removed by CSP and 283 polyps removed by HSP, 34 (10.7 %) and 21 (7.4 %) were incompletely resected, respectively, with an adjusted risk difference of 3.2 % (95 %CI -1.4 % to 7.8 %). There was no difference between the groups in terms of post-polypectomy bleeding, perforation, or abdominal pain. Independent risk factors for incomplete removal were serrated histology (odds ratio [OR] 3.96; 95 %CI 1.63 to 9.66) and hyperplastic histology (OR 2.52; 95 %CI 1.30 to 4.86) in adjusted analyses.

CONCLUSION

In this randomized trial, non-inferiority for CSP could not be demonstrated. Polyps with serrated histology are more prone to incomplete resection compared with adenomas. CSP can be used safely for small polyps in routine colonoscopy practice.

Associations of red and processed meat intake with screen-detected colorectal lesions

Limited data exist regarding the role of meat consumption in early-stage colorectal carcinogenesis. We examined associations of red and processed meat intake with screen-detected colorectal lesions in immunochemical fecal occult blood test (FIT)-positive participants, enrolled in the Norwegian CRCbiome study during 2017-2021, aged 55-77 years. Absolute and energy-adjusted intakes of red and processed meat (combined and individually) were assessed using a validated, semi-quantitative FFQ. Associations between meat intake and screen-detected colorectal lesions were examined using multinomial logistic regression analyses with adjustment for key covariates. Of 1162 participants, 319 presented with advanced colorectal lesions at colonoscopy. High v. low energy-adjusted intakes of red and processed meat combined, as well as red meat alone, were borderline to significantly positively associated with advanced colorectal lesions (OR of 1·24 (95 % CI 0·98, 1·57) and 1·34 (95 % CI 1·07, 1·69), respectively). A significant dose-response relationship was also observed for absolute intake levels (OR of 1·32 (95 % CI 1·09, 1·60) per 100 g/d increase in red and processed meat). For processed meat, no association was observed between energy-adjusted intakes and advanced colorectal lesions. A significant positive association was, however, observed for participants with absolute intake levels ≥ 100 v. < 50 g/d (OR of 1·19 (95 % CI 1·09, 1·31)). In summary, high intakes of red and processed meat were associated with presence of advanced colorectal lesions at colonoscopy in FIT-positive participants. The study demonstrates a potential role of dietary data to improve the performance of FIT-based screening.

Characteristics of non-participants in a randomized colorectal cancer screening trial comparing sigmoidoscopy and faecal immunochemical testing

Public health systems should guarantee universal access to health care services, including cancer screening. We assessed whether certain population subgroups were underrepresented among participants in colorectal cancer screening with sigmoidoscopy and faecal immunochemical testing (FIT). Between 2012 and 2019, about 140 000 individuals aged 50 to 74 years were randomly invited to once‐only sigmoidoscopy or first round of FIT screening. Our study included 46 919 individuals invited to sigmoidoscopy and 70 019 to FIT between 2012 and 2017. We used logistic regression models to evaluate if demographic and socioeconomic factors and use of certain drugs were associated with participation. Twenty‐four thousand one hundred and fifty‐nine (51.5%) individuals attended sigmoidoscopy and 40 931 (58.5%) FIT screening. Male gender, young age, low education and income, being retired or unemployed, living alone, being an immigrant, long driving time to screening centre, and use of antidiabetic and psychotropic drugs were associated with low participation in both screening groups. Many of these factors also predicted low acceptance of colonoscopy after positive FIT. While male gender, young age and living alone were more strongly associated with nonparticipation in FIT than sigmoidoscopy, low education and income, being retired or immigrant and long driving time were more strongly associated with nonparticipation in sigmoidoscopy than FIT. In conclusion, participation was lower in sigmoidoscopy than FIT. Predictors of nonparticipation were similar between arms. However, low socioeconomic status, being an immigrant and long driving time affected participation more in sigmoidoscopy screening, suggesting that FIT may guarantee more equal access to screening services than sigmoidoscopy.

Lifestyle predictors for inconsistent participation to fecal based colorectal cancer screening

BACKGROUND

Consistent participation in colorectal cancer (CRC) screening with repeated fecal immunochemical test (FIT) is important for the success of the screening program. We investigated whether lifestyle risk factors for CRC were related to inconsistent participation in up to four rounds of FIT-screening.

METHOD

We included data from 3,051 individuals who participated in up to four FIT-screening rounds and returned a lifestyle questionnaire. Using logistic regression analyses, we estimated associations between smoking habits, body mass index (BMI), physical activity, alcohol consumption, diet and a healthy lifestyle score (from least favorable 0 to most favorable 5), and inconsistent participation (i.e. not participating in all rounds of eligible FIT screening invitations).

RESULTS

Altogether 721 (24%) individuals were categorized as inconsistent participants Current smoking and BMI ≥30 kg/m² were associated with inconsistent participation; odds ratios (ORs) and 95% confidence intervals (CIs) were 1.54 (1.21-2.95) and 1.54 (1.20-1.97), respectively. A significant trend towards inconsistent participation by a lower healthy lifestyle score was observed (p < 0.05).

CONCLUSIONS

Lifestyle behaviors were associated with inconsistent participation in FIT-screening. Initiatives aimed at increasing participation rates among those with the unhealthiest lifestyle have a potential to improve the efficiency of screening.

The effect of train-the-colonoscopy-trainer course on colonoscopy quality indicators

BACKGROUND

Systematic training in colonoscopy is highly recommended; however, we have limited knowledge of the effects of "training-the-colonoscopy-trainer" (TCT) courses. Using a national quality register on colonoscopy performance, we aimed to evaluate the effects of TCT participation on defined quality indicators.

METHODS

This observational study compared quality indicators (pain, cecal intubation, and polyp detection) between centers participating versus not participating in a TCT course. Nonparticipating centers were assigned a pseudoparticipating year to match their participating counterparts. Results were compared between first year after and the year before TCT (pseudo)participation. Time trends up to 5 years after TCT (pseudo)participation were also compared. Generalized estimating equation models, adjusted for age, sex, and bowel cleansing, were used.

RESULTS

11 participating and 11 nonparticipating centers contributed 18 555 and 10 730 colonoscopies, respectively. In participating centers, there was a significant increase in detection of polyps ≥ 5 mm, from 26.4 % to 29.2 % (P = 0.035), and reduction in moderate/severe pain experienced by women, from 38.2 % to 33.6 % (P = 0.043); no significant changes were found in nonparticipating centers. Over 5 years, 20 participating and 18 nonparticipating centers contributed 85 691 and 41 569 colonoscopies, respectively. In participating centers, polyp detection rate increased linearly (P = 0.003), and pain decreased linearly in women (P = 0.004). Nonparticipating centers did not show any significant time trend during the study period.

CONCLUSIONS

Participation in a TCT course improved polyp detection rates and reduced pain experienced by women. These effects were maintained during a 5-year follow-up.

Women require routine opioids to prevent painful colonoscopies: a randomised controlled trial

BACKGROUND

Women are at high risk for painful colonoscopy. Pain, but also sedation, are barriers to colorectal cancer (CRC) screening participation. In a randomised controlled trial, we compared on-demand with pre-colonoscopy opioid administration to control pain in women at CRC screening age.

METHODS

Women, aged 55-79 years, attending colonoscopy at two Norwegian endoscopy units were randomised 1:1:1 to (1) fentanyl on-demand, (2) fentanyl prior to colonoscopy, or (3) alfentanil on-demand. The primary endpoint was procedural pain reported by the patients on a validated four-point Likert scale and further dichotomized for the study into painful (moderate or severe pain) and non-painful (slight or no pain) colonoscopy. Secondary endpoints were: willingness to repeat colonoscopy, adverse events, cecal intubation time and rate, and post-procedure recovery time.

RESULTS

Between June 2017 and May 2020, 183 patients were included in intention-to-treat analyses in the fentanyl on-demand group, 177 in the fentanyl prior to colonoscopy group, and 179 in the alfentanil on-demand group. Fewer women receiving fentanyl prior to colonoscopy reported a painful colonoscopy compared to those who were given fentanyl on-demand (25.2% vs. 44.1%, p < .001). There was no difference in the proportion of painful colonoscopies between fentanyl on-demand and alfentanil on-demand (44.1% vs. 39.5%, p = .40). No differences were observed for adverse events or any of the other secondary endpoints between the three groups.

CONCLUSIONS

Fentanyl prior to colonoscopy provided better pain control than fentanyl or alfentanil on-demand. Fentanyl before colonoscopy should be recommended to all women at screening age. Trial registration: Clinicaltrials.gov (NCT01538550). Norwegian Medicines Agency (16/16266-13). EU Clinical Trials Register (EUDRACTNR. 2016-005090-13).

Public Awareness and Perceptions of Colorectal Cancer Prevention: a Cross-Sectional Survey

We aimed to investigate awareness of colorectal cancer (CRC) lifestyle risk factors, willingness to participate in CRC screening, and preferences concerning channels for information on CRC prevention in the general population, including the target age of the upcoming Norwegian national CRC screening program. The present study was a cross-sectional online survey of adults aged 39 to 55 years registered as Kantar Web Panel respondents in Norway. The survey included demographic characteristics, multiple choice knowledge questions of lifestyle risk factors for CRC, attitudes towards CRC screening, and preferred channels for receiving information on CRC prevention. Of 4375 participants invited, 2007 (46%) answered the survey. The average number of correctly identified lifestyle risk factors for CRC was 7.3 of ten. Women were significantly more likely than men, and those with university or college education more likely than those with lower education to correctly identify at least eight risk factors (odds ratio, OR = 1.53, 95% confidence interval, CI 1.25-1.87, and OR = 1.51, 95% CI 1.23-1.86, respectively). The number of correctly identified risk factors was positively associated with willingness to participate in CRC screening (P for trend < 0.001). The national public work force and the Norwegian Cancer Society were selected by 76% and 69% of the participants, respectively, to be trustworthy sources of information on CRC prevention. Awareness of CRC risk factors was associated with willingness to participate in CRC screening. The national public work force and Cancer Society can be generally accepted sources of CRC preventive information.

The CRCbiome study: a large prospective cohort study examining the role of lifestyle and the gut microbiome in colorectal cancer screening participants

BACKGROUND

Colorectal cancer (CRC) screening reduces CRC incidence and mortality. However, current screening methods are either hampered by invasiveness or suboptimal performance, limiting their effectiveness as primary screening methods. To aid in the development of a non-invasive screening test with improved sensitivity and specificity, we have initiated a prospective biomarker study (CRCbiome), nested within a large randomized CRC screening trial in Norway. We aim to develop a microbiome-based classification algorithm to identify advanced colorectal lesions in screening participants testing positive for an immunochemical fecal occult blood test (FIT). We will also examine interactions with host factors, diet, lifestyle and prescription drugs. The prospective nature of the study also enables the analysis of changes in the gut microbiome following the removal of precancerous lesions.

METHODS

The CRCbiome study recruits participants enrolled in the Bowel Cancer Screening in Norway (BCSN) study, a randomized trial initiated in 2012 comparing once-only sigmoidoscopy to repeated biennial FIT, where women and men aged 50-74 years at study entry are invited to participate. Since 2017, participants randomized to FIT screening with a positive test result have been invited to join the CRCbiome study. Self-reported diet, lifestyle and demographic data are collected prior to colonoscopy after the positive FIT-test (baseline). Screening data, including colonoscopy findings are obtained from the BCSN database. Fecal samples for gut microbiome analyses are collected both before and 2 and 12 months after colonoscopy. Samples are analyzed using metagenome sequencing, with taxonomy profiles, and gene and pathway content as primary measures. CRCbiome data will also be linked to national registries to obtain information on prescription histories and cancer relevant outcomes occurring during the 10 year follow-up period.

DISCUSSION

The CRCbiome study will increase our understanding of how the gut microbiome, in combination with lifestyle and environmental factors, influences the early stages of colorectal carcinogenesis. This knowledge will be crucial to develop microbiome-based screening tools for CRC. By evaluating biomarker performance in a screening setting, using samples from the target population, the generalizability of the findings to future screening cohorts is likely to be high.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01538550 .

Detection of cancers and advanced adenomas in asymptomatic participants in colorectal cancer screening: a cross-sectional study

OBJECTIVES

To assess detection rates for colorectal cancer (CRC) and advanced adenomas in asymptomatic CRC screening participants and bowel symptoms in association with CRC and advanced adenoma.

DESIGN

Cross-sectional study.

SETTING

Two screening centres.

PARTICIPANTS

42 554 men and women, aged 50-74 years, participating in a randomised CRC screening trial. 36 059 participants underwent a sigmoidoscopy (and follow-up colonoscopy if positive sigmoidoscopy) and 6495 underwent a colonoscopy after a positive faecal immunochemical test (FIT).

PRIMARY AND SECONDARY OUTCOME MEASURES

Proportion of asymptomatic participants diagnosed with CRC or advanced adenomas. Prevalence of bowel symptoms (rectal bleeding, change in bowel habits, diarrhoea, constipation, bloating, alternating bowel habits, general symptoms, other bowel symptoms) recorded by the endoscopist and their association with CRC and advanced adenomas.

RESULTS

Among sigmoidoscopy participants, 7336 (20.3%) reported at least one symptom. 120 (60%) out of 200 individuals with screen-detected CRC and 1301 (76.5%) out of 1700 with advanced adenoma were asymptomatic. Rectal bleeding was associated with detection of CRC and advanced adenoma (OR 4.3, 95% CI 3.1 to 6.1 and 1.8, 95% CI 1.5 to 2.1, respectively), while change in bowel habits only with CRC detection (OR 3.8, 95% CI 2.4 to 6.1). Among the FIT positives, 2173 (33.5%) reported at least one symptom. Out of 299 individuals with screen-detected CRC and 1639 with advanced adenoma, 167 (55.9%) and 1 175 (71.7%) were asymptomatic, respectively. Detection of CRC was associated with rectal bleeding (OR 1.8, 95% CI 1.4 to 2.3), change in bowel habits (OR 2.2, 95% CI 1.4 to 3.5) and abdominal pain (OR 1.8, 95% CI 1.2 to 2.7).

CONCLUSIONS

Some bowel symptoms increased the likelihood of being diagnosed with CRC or advanced adenoma. However, the majority of individuals with these findings were asymptomatic. Asymptomatic individuals should be encouraged to participate in CRC screening.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov Identifier: NCT01538550.

Incomplete endoscopic resection of colorectal polyps: a prospective quality assurance study

BACKGROUND

 Endoscopic screening with polypectomy has been shown to reduce colorectal cancer incidence in randomized trials. Incomplete polyp removal and subsequent development of post-colonoscopy cancers may attenuate the effect of screening. This study aimed to quantify the extent of incomplete polyp removal.

METHODS

 We included patients aged 50-75 years with nonpedunculated polyps ≥ 5 mm removed during colonoscopy at four hospitals in Norway. To evaluate completeness of polyp removal, biopsies from the resection margins were obtained after polypectomy. Logistic regression models were fitted to identify factors explaining incomplete resection.

RESULTS

 246 patients with 339 polyps underwent polypectomy between January 2015 and June 2017. A total of 12 polyps were excluded due to biopsy electrocautery damage, and 327 polyps in 246 patients (mean age 67 years [range 42-83]; 52 % male) were included in the analysis. Overall, 54 polyps (15.9 %) in 54 patients were incompletely resected. Histological diagnosis of the polyp (sessile serrated lesions vs. adenoma, odds ratio [OR] 10.9, 95 % confidence interval [CI] 3.9-30.1) and polyp location (proximal vs. distal colon, OR 2.8, 95 %CI 1.0-7.7) were independent risk factors for incomplete removal of polyps 5-19 mm. Board-certified endoscopists were not associated with lower rates of incomplete resection compared with trainees (14.0 % vs. 14.2 %), OR 1.0 (95 %CI 0.5-2.1).

CONCLUSION

Incomplete polyp resection was frequent after polypectomy in routine clinical practice. Serrated histology and proximal location were independent risk factors for incomplete resection. The performance of board-certified gastroenterologists was not superior to that of trainees.

Colorectal Cancer Screening With Repeated Fecal Immunochemical Test Versus Sigmoidoscopy: Baseline Results From a Randomized Trial

BACKGROUND & AIMS

The comparative effectiveness of sigmoidoscopy and fecal immunochemical testing (FIT) for colorectal cancer (CRC) screening is unknown.

METHODS

Individuals aged 50-74 years living in Southeast Norway were randomly invited between 2012 and 2019 to either once-only flexible sigmoidoscopy or FIT screening every second year. Colonoscopy was recommended after sigmoidoscopy if any polyp of ≥10 mm, ≥3 adenomas, any advanced adenomas, or CRC was found or, subsequent to, FIT >15 μg hemoglobin/g feces. Data for this report were obtained after complete recruitment in both groups and included 2 full FIT rounds and part of the third round. Outcome measures were participation, neoplasia detection, and adverse events. Age-standardized detection rates and age-adjusted odds ratios (ORs) were calculated.

RESULTS

We included 139,291 individuals: 69,195 randomized to sigmoidoscopy and 70,096 to FIT. The participation rate was 52% for sigmoidoscopy, 58% in the first FIT round, and 68% for 3 cumulative FIT rounds. Compared to sigmoidoscopy, the detection rate for CRC was similar in the first FIT round (0.25% vs 0.27%; OR, 0.92; 95% confidence interval [CI], 0.75-1.13) but higher after 3 FIT rounds (0.49% vs 0.27%; OR, 1.87; 95% CI, 1.54-2.27). Advanced adenoma detection rate was lower in the first FIT round compared to sigmoidoscopy at 1.4% vs 2.4% (OR, 0.57; 95% CI, 0.53-0.62) but higher after 3 cumulative FIT rounds at 2.7% vs 2.4% (OR, 1.14; 95% CI, 1.05-1.23). There were 33 (0.05%) serious adverse events in the sigmoidoscopy group compared to 47 (0.07%) in the FIT group (P = .13).

CONCLUSIONS

Participation was higher and more CRC and advanced adenomas were detected with repeated FIT compared to sigmoidoscopy. The risk of perforation and bleeding was comparable. Clinicaltrials.gov, Number: NCT01538550.

Using Geant4 Monte Carlo toolkit to evaluate a low power X-ray tube generator configuration

Monte Carlo technique has been widely used as an important tool to develop new irradiation equipment, prototype medical equipment parts, and test methodologies for dosimetry. In this manuscript, we present a methodology to design a low power X-ray tube generator using the Geant4 Monte Carlo toolkit. The simulations were performed considering a large number of variables, namely, the material composition of the target track, the window thickness, and the air pressure of the X-ray tube. The X-ray production was simulated considering monoenergetic electron beams impinging on targets of tungsten and copper with incident kinetic energies ranging from 20 keV to 60 keV and initial divergences from 5° to 30°. For the polyenergetic emission, a conservative approach with Gaussian energy distribution was adopted. The analysis indicates that among the evaluated parameters, the incident kinetic energy, and the target material produced the most notable changes in the spectra shape and conversion efficiency (CE), significantly impacting the X-ray tube design. The studies provide a reliable methodology to explore general configurations for X-ray tube generators, defining the best geometry, material compositions, and thicknesses to be used on spectroscopy applications.

Survival and costs of colorectal cancer treatment and effects of changing treatment strategies: a model approach

New and emerging advances in colorectal cancer (CRC) treatment combined with limited healthcare resources highlight the need for detailed decision-analytic models to evaluate costs, survival and quality-adjusted life years. The objectives of this article were to estimate the expected lifetime treatment cost of CRC for an average 70-year-old patient and to test the applicability and flexibility of a model in predicting survival and costs of changing treatment scenarios. The analyses were based on a validated semi-Markov model using data from a Norwegian observational study (2049 CRC patients) to estimate transition probabilities and the proportion resected. In addition, inputs from the Norwegian Patient Registry, guidelines, literature, and expert opinions were used to estimate resource use. We found that the expected lifetime treatment cost for a 70-year-old CRC patient was €47,300 (CRC stage I €26,630, II €38,130, III €56,800, and IV €69,890). Altered use of palliative chemotherapy would increase the costs by up to 29%. A 5% point reduction in recurrence rate for stages I-III would reduce the costs by 5.3% and increase overall survival by 8.2 months. Given the Norwegian willingness to pay threshold per QALY gained, society's willingness to pay for interventions that could result in such a reduction was on average €28,540 per CRC patient. The life years gained by CRC treatment were 6.05 years. The overall CRC treatment costs appear to be low compared to the health gain, and the use of palliative chemotherapy can have a major impact on cost. The model was found to be flexible and applicable for estimating the cost and survival of several CRC treatment scenarios.

Continuous development of colorectal cancer screening programs

Colorectal cancer (CRC) screening programs are far from perfect. Many crucial questions remain, yet expensive CRC screening services are implemented throughout the world without a plan on how to evaluate and improve the service. The time is ripe for improving the design of CRC screening programs.

Effects of Oral Anticoagulants and Aspirin on Performance of Fecal Immunochemical Tests in Colorectal Cancer Screening

BACKGROUND & AIMS

The fecal immunochemical test (FIT) is the tool most frequently used for colorectal cancer (CRC) screening worldwide. It is unclear how the use of aspirin and oral anticoagulants in the screening population affects the diagnostic performance of FIT.

METHODS

We performed a cross-sectional study in an ongoing CRC screening trial in Norway. Participants aged 50-74 years with a positive result from an FIT (>15 μg hemoglobin/g feces) and subsequent colonoscopy (reference standard) were included. Those who used regular aspirin, warfarin, or direct-acting oral anticoagulants (DOACs) were defined as users. Non-users were matched according to age, sex, screening center, and screening round. The primary outcomes were the positive predictive value (PPV) for CRC and advanced adenoma.

RESULTS

Among 4908 eligible participants, 1008 used aspirin, 147 used warfarin, 212 used DOACs, and 3541 were non-users. CRCs were found in 234 individuals and advanced adenomas in 1305 individuals. The PPV for CRC was 3.8% for aspirin users vs 6.4% for matched non-users (P = .006), The PPV for advanced adenoma in aspirin users was 27.2% vs 32.6% for matched non-users (P = .011). For DOAC, the PPV for CRC was 0.9% in users vs 6.8% in matched non-users (P = .001). The PPV for advanced adenoma in DOAC users was 20.5% vs 32.4% in matched non-users (P = .002). There was no significant difference in PPV for CRC or advanced adenoma in warfarin users compared to non-users.

CONCLUSIONS

In a large screening cohort in Norway, regular use of aspirin and particularly DOACs, were associated with lower PPV of FIT for detection of CRCs and advanced adenomas. ClinicalTrials.gov ID NCT01538550.

Thyroidectomy Versus Medical Management for Euthyroid Patients With Hashimoto Disease and Persisting Symptoms: A Randomized Trial

BACKGROUND

Hashimoto disease is a chronic autoimmune thyroiditis. Despite adequate hormone substitution, some patients have persistent symptoms that may be the result of immunologic pathophysiology.

OBJECTIVE

To determine whether thyroidectomy improves symptoms in patients with Hashimoto thyroiditis who still have symptoms despite having normal thyroid gland function while receiving medical therapy.

DESIGN

Randomized trial. (ClinicalTrials.gov: NCT02319538).

SETTING

Secondary care hospital in Norway.

PATIENTS

150 patients aged 18 to 79 years with persistent Hashimoto-related symptoms despite euthyroid status while receiving hormone replacement therapy and with serum antithyroid peroxidase (anti-TPO) antibody titers greater than 1000 IU/mL.

INTERVENTION

Total thyroidectomy or medical management with hormone substitution to secure euthyroid status in both groups.

MEASUREMENTS

The primary outcome was general health score on the Short Form-36 Health Survey (SF-36) at 18 months. Secondary outcomes were adverse effects of surgery, the other 7 SF-36 subscores, fatigue questionnaire scores, and serum anti-TPO antibody titers at 6, 12, and 18 months.

RESULTS

During follow-up, only the surgical group demonstrated improvement: Mean general health score increased from 38 to 64 points, for a between-group difference of 29 points (95% CI, 22 to 35 points) at 18 months. Fatigue score decreased from 23 to 14 points, for a between-group difference of 9.3 points (CI, 7.4 to 11.2 points). Chronic fatigue frequency decreased from 82% to 35%, for a between-group difference of 39 percentage points (CI, 23 to 53 percentage points). Median serum anti-TPO antibody titers decreased from 2232 to 152 IU/mL, for a between-group difference of 1148 IU/mL (CI, 1080 to 1304 IU/mL). In multivariable regression analyses, the adjusted treatment effects remained similar to the unadjusted effects.

LIMITATION

Results are applicable only to a subgroup of patients with Hashimoto disease, and follow-up was limited to 18 months.

CONCLUSION

Total thyroidectomy improved health-related quality of life and fatigue, whereas medical therapy did not. This improvement, along with concomitant elimination of serum anti-TPO antibodies, may elucidate disease mechanisms.

PRIMARY FUNDING SOURCE

Telemark Hospital.

Effectiveness of digital feedback on patient experience and 30-day complications after screening colonoscopy: a randomized health services study

Background and study aims  European guidelines (ESGE) recommend measuring patient experience and 30-day complication rate after colonoscopy. We compared digital and paper-based feedback on patients' experience and 30-day complications after screening colonoscopy. Patients and methods  Screenees attending for primary screening colonoscopies in two centers from September 2015 to December 2016 were randomized (1:1) to an intervention arm (choice of feedback method) or control arm (routine paper-based feedback). Participants in the intervention arm could choose preferred feedback method (paper-based, automated telephone or online survey) and were contacted by automated telephone 30 days after colonoscopy to assess complications. Control group participants self-reported complications. Primary and secondary endpoints were response rates to feedback and complications questionnaire, respectively. Results  There were 1,281 and 1,260 participants in the intervention and control arms, respectively. There was no significant difference in response rate between study groups (64.8 % vs 61.5 %; P  = 0.08). Free choice of feedback improved response for participants identified as poor responders: younger than 60 years (60.8 % vs 54.7 %; P  = 0.031), male (64.0 % vs 58.6 %; P  = 0.045) and in small non-public center (56.2 % vs 42.5 %; P  = 0.043). In the intervention arm, 1,168 participants (91.2 %) answered the phone call concerning complications. A total of 79 participants (6.2 %) reported complications, of which two (0.2 %) were verified by telephone as clinically relevant. No complications were self-reported in the control group. Conclusion  The overall response rate was not significantly improved with digital feedback, yet the technology yielded significant improvement in participants defined as poor responders. Our study demonstrated feasibility and efficacy of digital patient feedback about complications after colonoscopy.

Polyp detection rates as quality indicator in clinical versus screening colonoscopy

Background Adenoma and Polyp Detection Rates (ADR and PDR) are advocated as general performance measures for screening and clinical colonoscopy, but their evidence is largely derived from screening data. This study compares PDRs in colonoscopy for screening versus clinical indications.

Methods Consecutive patients at two Norwegian centers were examined by eight endoscopists either for colonoscopy screening in a randomized colonoscopy screening trial (Nordic-European Initiative on Colorectal Cancer, NordICC) or for clinical indications during the same time period (January 2013 to December 2014). PDR-5 mm, defined as the proportion of colonoscopies with detection of at least one polyp with diameter ≥ 5 mm, was measured prospectively. We fitted multivariable logistic regression models and calculated the adjusted odds ratios (OR) to evaluate factors for differences in PDR-5 mm between screening and clinical colonoscopies.

Results The study included 2939 clinical and 771 screening colonoscopies. The PDR-5 mm was 26 % and 31 %, respectively (P = 0.005). Among sex, age, cecum intubation, bowel cleansing, and endoscopist, only the latter explained the higher PDR-5 mm in screening compared to routine colonoscopy. In the fully adjusted logistic regression model, the detection of polyps ≥ 5 mm was not associated with indication for colonoscopy. The OR for polyp detection in screening vs. routine colonoscopy was 1.04; 95 % confidence interval 0.85 – 1.27.

Conclusion In this study, the differences in PDR-5 mm between clinical and screening colonoscopies could be explained by the endoscopist. Accordingly, PDR-5 mm benchmarks may be similar for clinical and screening colonoscopy.

Registration bias in a clinical quality register

Background and aims  The quality of medical quality registers is poorly defined and lack of trust in data due to low completeness may be a major barrier against their use in quality improvement interventions. The aim of the current observational study was to explore how selective reporting may influence adverse events registered in the Norwegian quality register for colonoscopy (Gastronet). Materials and methods  Gastronet's database includes data provided by endoscopists, nurses and patients. All outpatient colonoscopies reported to Gastronet in 2015 were included and compared to the total number of colonoscopies performed in Norway as retrieved from the National Patient Registry. Hospitals were categorized into four groups according to reporting completeness < 50 %, 50 % to 69 %, 70 % to 89 % and ≥ 90 %. The number of recorded adverse events (AEs) and procedure time were analyzed. Multivariate logistic regression models were fitted to explore independent factors for selection bias. Results  A total of 22,364 colonoscopies were reported to the National Patient Register of which 15,855 (71 %) were registered in Gastronet. Feedback was received from 11,079 patients (50 %). The frequency of AEs increased from 0.6 % in completeness group < 50 % to 1.6 % in completeness group ≥ 90 % ( P  < 0.001). Long colonoscopy procedure time was associated with low reporting completeness. Patient feedback was associated with older age, cecal intubation success and sedation-free colonoscopy. Conclusion  Incomplete registration in a colonoscopy quality register is associated with underreporting of AEs. Longer procedure time, a surrogate marker for time constraint, is associated with low completeness.

Mortality From Postscreening (Interval) Colorectal Cancers Is Comparable to That From Cancer in Unscreened Patients-A Randomized Sigmoidoscopy Trial

BACKGROUND & AIMS

Endoscopic screening for colorectal cancer (CRC) is performed at longer time intervals than the fecal occult blood test or screenings for breast or prostate cancer. This causes concerns about interval cancers, which have been proposed to progress more rapidly. We compared outcomes of patients with interval CRCs after sigmoidoscopy screening vs outcomes of patients with CRC who had not been screened.

METHODS

We performed a secondary analysis of a randomized sigmoidoscopy screening trial in Norway with 98,684 participants (age range, 50-64 years) who were randomly assigned to groups that were (n = 20,552) or were not (n = 78,126) invited for sigmoidoscopy screening from 1999 through 2001; participants were followed up for a median 14.8 years. We compared CRC mortality and all-cause mortality between individuals who underwent screening and were diagnosed with CRC 30 days or longer after screening (interval cancer group, n = 163) and individuals diagnosed with CRC in the nonscreened group (controls, n = 1740). All CRCs in the control group were identified when they developed symptoms (clinically detected CRCs). Analyses were stratified by cancer site. We used Cox regression to estimate hazard ratio (HRs), adjusted for age and sex.

RESULTS

Over the follow-up period, 43 individuals in the interval cancer group died from CRC; among controls, 525 died from CRC. CRC mortality (adjusted HR, 0.98; 95% confidence interval, 0.72-1.35; P = .92), rectosigmoid cancer mortality (adjusted HR, 1.10; 95% confidence interval, 0.63-1.92; P = .74), and all-cause mortality (adjusted HR, 0.99; 95% confidence interval, 0.76-1.27; P = .91) did not differ significantly between the interval cancer group and controls.

CONCLUSIONS

In this randomized sigmoidoscopy screening trial, mortality did not differ significantly between individuals with interval CRCs and unscreened patients with clinically detected CRCs. ClinicalTrials.gov identifier: NCT00119912.

Evaluating gut microbiota profiles from archived fecal samples

BACKGROUND

Associations between colorectal cancer and microbiota have been identified. Archived fecal samples might be valuable sample sources for investigating causality in carcinogenesis and biomarkers discovery due to the potential of performing longitudinal studies. However, the quality, quantity and stability of the gut microbiota in these fecal samples must be assessed prior to such studies. We evaluated i) cross-contamination during analysis for fecal blood and ii) evaporation in stored perforated fecal immunochemical tests (iFOBT) samples, iii) temperature stability as well as iv) comparison of the gut microbiota diversity and composition in archived, iFOBT and fresh fecal samples in order to assess feasibility of large scale microbiota studies.

METHODS

The microbiota profiles were obtained by sequencing the V3-V4 region of 16S rDNA gene.

RESULTS

The iFOBT does not introduce any cross-sample contamination detectable by qPCR. Neither could we detect evaporation during freeze-thaw cycle of perforated iFOBT samples. Our results confirm room temperature stability of the gut microbiome. Diverse microbial profiles were achieved in 100% of fresh, 81% of long-term archived and 96% of iFOBT samples. Microbial diversity and composition were comparable between fresh and iFOBT samples, however, diversity differed significantly between long-term archived, fresh and iFOBT samples.

CONCLUSION

Our data showed that it is feasible to exploit archived fecal sample sets originally collected for testing of fecal blood. The advantages of using these sample sets for microbial biomarker discovery and longitudinal observational studies are the availability of high-quality diagnostic and follow-up data. However, care must be taken when microbiota are profiled in long-term archived fecal samples.

Improving Cancer Preventive Behaviors: A Randomized Trial of Tailored Lifestyle Feedback in Colorectal Cancer Screening

BACKGROUND

Cancer screening provides an opportunity to increase awareness of cancer-preventive lifestyle behaviors such as nonsmoking, physical activity, low alcohol consumption, and a healthy diet. We tested the effect of standardized, individually tailored written feedback (TF), and a standard leaflet (SL) on 1-year lifestyle behaviors in a colorectal cancer screening setting.

METHODS

A total of 3,642 men and women aged 50-74 years invited to sigmoidoscopy screening were randomly assigned to: (i) TF; (ii) SL for cancer-preventive lifestyle behaviors; or (iii) control. Participants were mailed two self-reported lifestyle questionnaires (LSQ) 1 year apart. The TF intervention was based on the prescreening LSQ answers. We analyzed differences [with 95% confidence intervals (CI)] by comparing prescreening to 1-year follow-up of single cancer-preventive factors and the number of cancer-preventive lifestyle behaviors (range 0-4) between the groups by multivariable logistic regression and analysis of covariance (ANCOVA).

RESULTS

A total of 1,054 screening participants without neoplastic findings (29% of those invited to screening) were included in this study. Participants in the TF group increased their number of cancer-preventive lifestyle behaviors significantly compared with those in the control group by 0.11 (95% CI, 0.02 to 0.19). Overweight/obese individuals in the TF group had a -0.84 kg (95% CI, -1.47 to -0.22) larger reduction in body weight compared with the control group.

CONCLUSIONS

TF at sigmoidoscopy screening led to small improvements in cancer-preventive behaviors.

IMPACT

Colorectal cancer screening is a suitable setting for increasing awareness of cancer-preventive behavior.

Modifiable factors associated with patient-reported pain during and after screening colonoscopy

OBJECTIVE

Pain associated with colonoscopy is a major burden for patients. We investigated modifiable factors associated with patient-reported pain during and after colonoscopy.

DESIGN

This cross-sectional analysis included database records from 23 centres participating in a population-based colonoscopy screening programme in Poland. Colonoscopies were performed under three sedation modalities: none, benzodiazepine-opioid sedation or propofol sedation. We used Gastronet (a validated tool) to assess patients' pain during and after colonoscopy; pain was scored on a four-point scale (no, little, moderate or severe pain), with moderate to severe defined as painful. We used multivariate logistic regression models to estimate ORs for painful colonoscopy and calculated risk-adjusted ratios of painful colonoscopies per endoscopist and compared it to the mean rate.

RESULTS

Of 35 216 screening colonoscopies in 2014 and 2015 included in our study, 22 725 (64.5%) patients returned valid Gastronet questionnaires. The proportion of examinations described as causing pain during (after) the procedure was 22.5% (14.2%) for unsedated, 19.9% (13.5%) for benzodiazepine-opioid sedation and 2.5% (7.5%) for propofol sedation. Propofol sedation, higher case volume of endoscopists, newest endoscope generation and adequate bowel preparation were significantly associated with lower odds of painful colonoscopy. Pain scores after colonoscopy showed similar associations. Adjusted pain rates during and after colonoscopy varied 11 and over 23-fold, respectively, between endoscopists.

CONCLUSION

We identified several independent, modifiable factors associated with pain during and after colonoscopy, of which individual endoscopist was the most important. Dedicated training should be considered to decrease variability among endoscopists.

Number of Adenomas Removed and Colorectal Cancers Prevented in Randomized Trials of Flexible Sigmoidoscopy Screening

BACKGROUND & AIMS

Screening for colorectal cancer (CRC) with sigmoidoscopy reduces CRC incidence by detecting and removing adenomas. The number needed to screen is a measure of screening efficiency, but is not directly associated with adenoma removal. We propose the following 2 new metrics for quantifying the relationship between adenoma removal and CRC prevented: number of adenomas needed to remove (NNR) and adenoma dwell time avoided (DTA).

METHODS

We collected data from 4 randomized trials of sigmoidoscopy screening (1 in the United States and 3 in Europe) to assess NNR and DTA. For each trial, NNR was computed as the number of adenomas removed from subjects in the intervention group, divided by the number of CRCs prevented. DTA was computed similarly but taking into account the timing of adenoma removal. Combined results across trials were assessed using standard meta-analytic techniques.

RESULTS

The estimated NNR for the PLCO (Prostate, Lung, Colorectal and Ovarian) trial was 74 (95% confidence interval [CI], 56-110), for the NORCCAP (Norwegian Colorectal Cancer Prevention) trial was 71 (95% CI, 44-174), for the SCORE (Screening for Colon Rectum) trial was 27 (95% CI, 14-135), and for the UKFSST (UK Flexible Sigmoidoscopy Screening Trial) was 36 (95% CI, 28-52). The combined estimate (meta-analysis) of NNR was 52 (95% CI, 36-93) assuming heterogeneity (P for heterogeneity = .014). DTA estimates among trials ranged from 278 to 730 years, with a combined estimate of 500 (95% CI, 344-833) years assuming heterogeneity (P for heterogeneity = .035), or 2 CRC cases prevented per 1000 adenoma dwell years avoided. The combined estimates of NNR and DTA restricted to advanced adenomas were 13 (95% CI, 9-22) and 122 (95% CI, 90-190) years, respectively.

CONCLUSIONS

We collected data from 4 randomized trials of sigmoidoscopy screening for CRC to develop metrics of endoscopic efficiency, NNR and DTA, which are directly linked to adenoma detection and removal. They can be used to compare screening among endoscopic modalities and to more precisely measure adenoma to carcinoma transition rates.

Endoscopy assistants influence the quality of colonoscopy

BACKGROUND

Colonoscopy performance varies between endoscopists, but little is known about the impact of endoscopy assistants on key performance indicators. We used a large prospective colonoscopy quality database to perform an exploratory study to evaluate differences in selected quality indicators between endoscopy assistants.

METHODS

All colonoscopies reported to the Norwegian colonoscopy quality assurance register Gastronet can be used to trace individual endoscopy assistants. We analyzed key quality indicators (cecum intubation rate, polyp detection rate, colonoscopies rated as severely painful, colonoscopies with sedation or analgesia, and satisfaction with information) for colonoscopies performed between 1 January 2013 and 31 December 2014. Differences between individual assistants were analyzed by fitting multivariable logistic regression models, with the best performing assistant at each participating hospital as reference. All models were adjusted for the endoscopist.

RESULTS

63 endoscopy assistants from 12 hospitals assisted in 15 365 colonoscopies. Compared with their top performing peers from the same hospital, one assistant was associated with cecum intubation failure, four with poor polyp detection, nine with painful colonoscopy, 16 with administration of sedation or analgesics during colonoscopy, and three with patient dissatisfaction about information given relating to the colonoscopy. The number of procedures during the study period or lifetime experience as an endoscopy assistant were not associated with any quality indicator.

CONCLUSION

In this exploratory study, there was little variation on important colonoscopy quality indicators between endoscopy assistants. However, there were differences among assistants that may be clinically important. Endoscopy assistants should be subject to quality surveillance similarly to endoscopists.

Bond-Breaking Efficiency of High-Energy Ions in Ultrathin Polymer Films

Thin films of poly(methyl methacrylate) and poly(vinyl chloride) of different thickness are used to investigate the effect of spatial confinement on the efficiency of bond breaking induced by 2 MeV H^{+} and 2.1 GeV Bi ions. Effective cross sections for oxygen and chlorine loss are extracted for films down to a thickness of about 5 nm and are compared to theoretical estimations based on radial energy density profiles simulated with geant-dna. The cross sections are to a large extent thickness independent, indicating that bond breaking is dominated by short-range processes. This is in contrast to the strongly reduced efficiencies found recently for cratering induced by high-energy ions in similar ultrathin polymer films [Phys. Rev. Lett. 114, 118302 (2015)PRLTAO0031-900710.1103/PhysRevLett.114.118302].

Polypectomy techniques among gastroenterologists in Norway - a nationwide survey

BACKGROUND AND STUDY AIMS

 Incomplete polyp removal has been estimated to cause 27 % of all colorectal cancers detected soon after colonoscopy. There is limited information regarding polypectomy techniques among endoscopists. The article is a nationwide survey of polypectomy techniques among Norwegian endoscopists.

MATERIALS AND METHODS

 We invited all board-certified gastroenterologists in Norway to complete a web-based questionnaire about their polypectomy technique. Inadequate polypectomy techniques were defined as using biopsy forceps for polyps larger than 3 mm in diameter, using hot biopsy forceps for polypectomy, and using the same electrocautery output irrespective of polyp size and morphology.

RESULTS

Twenty-six of 30 Norwegian gastroenterology departments participated in the study. A total of 119 endoscopists received the survey, and 70 (59 %) responded. Mean duration of endoscopy practice was 11.5 years, and 95 % had performed more than 1,000 colonoscopies during their career. Twenty-eight endoscopists (40 %) used one or more inadequate polypectomy techniques: 10 (14.3 %) used biopsy forceps for removal of polyps larger than 3 mm in diameter, five (7.1 %) used hot biopsy for polypectomy, and 17 (24 %) used the same electrocautery output for all polypectomies. Five (7 %) endoscopists reported that they did not remove polyps smaller than 4 mm.

CONCLUSION

 A substantial number of Norwegian endoscopists use inadequate polypectomy techniques. Improved training and certification of endoscopists is warranted.

Long-Term Effectiveness of Sigmoidoscopy Screening on Colorectal Cancer Incidence and Mortality in Women and Men: A Randomized Trial

BACKGROUND

The long-term effects of sigmoidoscopy screening on colorectal cancer (CRC) incidence and mortality in women and men are unclear.

OBJECTIVE

To determine the effectiveness of flexible sigmoidoscopy screening after 15 years of follow-up in women and men.

DESIGN

Randomized controlled trial. (ClinicalTrials.gov: NCT00119912).

SETTING

Oslo and Telemark County, Norway.

PARTICIPANTS

Adults aged 50 to 64 years at baseline without prior CRC.

INTERVENTION

Screening (between 1999 and 2001) with flexible sigmoidoscopy with and without additional fecal blood testing versus no screening. Participants with positive screening results were offered colonoscopy.

MEASUREMENTS

Age-adjusted CRC incidence and mortality stratified by sex.

RESULTS

Of 98 678 persons, 20 552 were randomly assigned to screening and 78 126 to no screening. Adherence rates were 64.7% in women and 61.4% in men. Median follow-up was 14.8 years. The absolute risks for CRC in women were 1.86% in the screening group and 2.05% in the control group (risk difference, -0.19 percentage point [95% CI, -0.49 to 0.11 percentage point]; HR, 0.92 [CI, 0.79 to 1.07]). In men, the corresponding risks were 1.72% and 2.50%, respectively (risk difference, -0.78 percentage point [CI, -1.08 to -0.48 percentage points]; hazard ratio [HR], 0.66 [CI, 0.57 to 0.78]) (P for heterogeneity = 0.004). The absolute risks for death from CRC in women were 0.60% in the screening group and 0.59% in the control group (risk difference, 0.01 percentage point [CI, -0.16 to 0.18 percentage point]; HR, 1.01 [CI, 0.77 to 1.33]). The corresponding risks for death from CRC in men were 0.49% and 0.81%, respectively (risk difference, -0.33 percentage point [CI, -0.49 to -0.16 percentage point]; HR, 0.63 [CI, 0.47 to 0.83]) (P for heterogeneity = 0.014).

LIMITATION

Follow-up through national registries.

CONCLUSION

Offering sigmoidoscopy screening in Norway reduced CRC incidence and mortality in men but had little or no effect in women.

PRIMARY FUNDING SOURCE

Norwegian government and Norwegian Cancer Society.

Monte Carlo Simulation Used to Calculate Energy Correction Factor for Thermoluminescent Dosimeters Used by Occupational Workers on Pediatric Exams

The main objective of this work is to simulate the X-ray scattered spectra by different pediatric phantoms (simulation of children subjected to barium meal procedures) to calculate an energy correction factor (ECF) to the reading of thermoluminescent dosimeters (TLDs). To perform this evaluation, the TLDs were positioned over three areas in two occupational workers: eyes, thyroid and hands. The Geant4 toolkit was used to define the spectra collected by TLDs, making possible to calculate the ECF. This work was developed in two stages: (1) evaluation of scattered spectra by different standard phantoms (newborn, 1, 5 and 10 years old); (2) definition of the ECF to the absorbed energy by each TLD. Geant4 shows to be a good toolkit to calculate the ECF and among the different characteristics evaluated, in this work, the TLD position and acceleration voltages are the most significant parameters that may influence the ECF calculated.

Acceptability of two colorectal cancer screening tests: pain as a key determinant in sigmoidoscopy

Background Participants' experience with a screening test can influence adherence, and therefore the efficacy of screening programs. We compared screening with unsedated flexible sigmoidoscopy and fecal immunochemical testing (FIT) for participants' satisfaction with the decision and for willingness to repeat colorectal cancer screening. Methods In a prospective, randomized trial 3257 individuals (50 - 74 years) were invited to either flexible sigmoidoscopy or FIT (1:1), of whom 1650 took up the offer (52.6 %). In total, 1497 screening participants completed at least one questionnaire, either before screening, and/or at three time points in the following year, that measured willingness to repeat screening, willingness to recommend screening, and satisfaction with decision to attend. There were 769 and 728 responders in the flexible sigmoidoscopy and FIT group, respectively. Additionally, 581 flexible sigmoidoscopy participants also completed a pain questionnaire. Results 1 year later, 10 % of the flexible sigmoidoscopy participants were not willing to repeat screening, compared to 5 % of FIT participants. A higher percentage of women compared to men would not repeat flexible sigmoidoscopy screening (adjusted odds ratio [OR] 2.52, 95 % confidence interval [95 %CI] 1.48 to 4.28). Notably, 22 % of women reported pain during flexible sigmoidoscopy compared to 5 % of men. When we added pain to the statistical model, pain was significantly associated with unwillingness to repeat flexible sigmoidoscopy (OR 3.15, 95 %CI 1.68 to 5.87), while gender was no longer associated (OR 1.53, 95 %CI 0.82 to 2.88). Conclusion Acceptability for flexible sigmoidoscopy and for FIT was high among Norwegian screening participants, though FIT participants were more willing to repeat screening. Women were less willing to repeat screening with flexible sigmoidoscopy compared to men. This gender difference seemed partly due to pain, and therefore preventable.This study is registered at ClinicalTrials.gov: NCT01538550.

Lifestyle predictors for non-participation and outcome in the second round of faecal immunochemical test in colorectal cancer screening

BACKGROUND

To reduce colorectal cancer (CRC) mortality through population-based screening programmes using faecal tests, it is important that individuals continue to participate in the repeated rounds of screening. We aimed to identify lifestyle predictors for discontinuation of faecal immunochemical test (FIT) screening after the first round, as well as lifestyle predictors for colorectal neoplasia detected in the second-round FIT screening.

METHODS

In this longitudinal study, we invited 6959 individuals aged 50-74 years from south-east Norway for a first round of FIT screening and to complete a self-reported lifestyle questionnaire on demographic factors, body mass index (BMI, kg m-2), smoking habits, physical activity, consumption of alcohol and dietary items. Two years later, we estimated the associations between these factors, non-participation and screening results in the second round of FIT screening using adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Of the 3114 responders to the questionnaire who completed the first-round FIT and who were invited to participate in second-round FIT screening, 540 (17%) did not participate. The OR and (95% CI) for discontinuation of FIT screening after the first round was 1.61 (1.24-2.10) for current smoking compared with non-smoking; 2.01 (1.25-3.24) for BMI⩾35 kg m-2 compared with BMI 16.9-24.9 kg m-2 and 0.70 (0.52-0.94) for physical activity in the third quartile vs the first. Among participants, smoking, high BMI and high alcohol consumption were associated with an increased odds of detecting colorectal neoplasia (n=107).

CONCLUSIONS

These results may indicate that Norwegian FIT screening participants who discontinue after the first round have lifestyle behaviours associated with increased risk of CRC.