Targeted screening for colorectal cancer in high-risk individuals

Colorectal Cancer Screening in the Middle East: What, Why, Who, When, and How?

The incidence of colorectal cancer (CRC) in the Middle East is increasing, especially among those younger than 50 years. Risk factors including obesity, sedentary lifestyle, and dietary changes are associated with the epidemiologic shift and are a result of socioeconomic changes happening in the region. Worldwide, CRC screening is associated with decreased incidence and mortality of CRC, but screening uptake is still low in the Middle East because of cultural barriers and lack of awareness; in addition, most countries do not have national screening programs. Knowledge of CRC screening and participation rates vary among different countries, but overall they are low. Both primary and secondary prevention approaches are needed in the Middle East, and cost-effectiveness is important in choosing screening modalities. Although colonoscopy is considered the most robust screening method, stool-based testing may be an acceptable screening strategy in resource-limited settings, and focusing on high-risk individuals such as those with hereditary CRC might be the most cost-effective strategy. In addition to financial limitations in many countries in the Middle East, human displacement places an extra toll on cancer control strategies in the region.

Systematic review of shared decision-making in guidelines about colorectal cancer screening

INTRODUCTION

We aimed to systematically evaluate quality of shared decision-making (SDM) in colorectal cancer (CRC) screening clinical practice guidelines (CPGs) and consensus statements (CSs).

METHODS

Search for CRC screening guidances was from 2010 to November 2021 in EMBASE, Web of Science, MEDLINE, Scopus and CDSR, and the World Wide Web. Three independent reviewers and an arbitrator rated the quality of each guidance using a SDM quality assessment tool (maximum score: 31). Reviewer agreement was 0.88.

RESULTS

SDM appeared in 41/83 (49.4%) CPGs and 9/19 (47.4%) CSs. None met all the quality criteria, and 51.0% (52/102) failed to meet any quality items. Overall compliance was low (mean 1.63, IQR 0-2). Quality was better in guidances published after 2015 (mean 1, IQR 0-3 vs. mean 0.5, IQR 0-1.5; p = 0.048) and when the term SDM was specifically reported (mean 4.5, IQR 2.5-4.5 vs. mean 0.5, IQR 0-1.5; p < 0.001). CPGs underpinned by systematic reviews showed better SDM quality than consensus (mean 1, IQR 0-3 vs. mean 0, IQR 0-2, p = 0.040).

CONCLUSION

SDM quality was suboptimal and mentioned in less than half of the guidances, and recommendations were scarce. Guideline developers should incorporate evidence-based SDM recommendations in guidances to underpin the translation of evidence into practice.

A scoping review of risk-stratified bowel screening: current evidence, future directions

PURPOSE

In this scoping review, we examined the international literature on risk-stratified bowel screening to develop recommendations for future research, practice and policy.

METHODS

Six electronic databases were searched from inception to 18 October 2021: Medline, Embase, PsycINFO, CINAHL, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials. Forward and backwards citation searches were also undertaken. All relevant literature were included.

RESULTS

After de-deduplication, 3,629 records remained. 3,416 were excluded at the title/abstract screening stage. A further 111 were excluded at full-text screening stage. In total, 102 unique studies were included. Results showed that risk-stratified bowel screening programmes can potentially improve diagnostic performance, but there is a lack of information on longer-term outcomes. Risk models do appear to show promise in refining existing risk stratification guidelines but most were not externally validated and less than half achieved good discriminatory power. Risk assessment tools in primary care have the potential for high levels of acceptability and uptake, and therefore, could form an important component of future risk-stratified bowel screening programmes, but sometimes the screening recommendations were not adhered to by the patient or healthcare provider. The review identified important knowledge gaps, most notably in the area of organisation of screening services due to few pilots, and what risk stratification might mean for inequalities.

CONCLUSION

We recommend that future research focuses on what organisational challenges risk-stratified bowel screening may face and a consideration of inequalities in any changes to organised bowel screening programmes.

Global Prevalence of Colorectal Neoplasia: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Most colorectal cancers (CRC) arise from colorectal adenomas, yet there is not enough information on global prevalence to inform health care policy. We examined the prevalence of any type of adenomas, advanced adenomas (AADs), and CRC according to age, sex, ethnicity, geographic regions, and anatomic location (proximal vs distal).

METHODS

MEDLINE and Embase were searched from their inception through May 1, 2018, to identify population-based, observational studies that reported the prevalence of colorectal neoplasia. Studies on participants 15 years or older, with a sample size of 500 persons or more, were included. Metaprop (College Station, TX) was used to model within-study variability by binomial distribution and Freeman-Tukey Double Arcsine Transformation to stabilize the variances. The prevalence figures were presented by proportions and their 95% CIs using random-effects models.

RESULTS

Our meta-analysis included 70 studies involving 637,414 individuals. The overall prevalence rates of adenoma (23.9%; 95% CI, 22.2%-25.8%), AAD (4.6%; 95% CI, 3.8%-5.5%), and CRC (0.4%, 95% CI, 0.3%-0.5%) were calculated. Subgroup analysis indicated that prevalence values (adenomas, AADs, and CRCs) were higher among men (29.7%, 6.5%, and 0.8%, respectively) than women (19.3%, 3.8% and 0.4%, respectively), among older adults (25.9%, 5.2%, and 0.6%, respectively) than younger adults (14.6%, 1.6%, and 0.1%, respectively), among Caucasians (23.7%, 6.6%, and 0.5%, respectively) than other ethnicities, in European countries (25.9%, 8.4%, and 0.8%, respectively) than other countries, and among patients with proximal (25.9%, 5.3%, and 0.1%, respectively) vs distal neoplasia.

CONCLUSIONS

In a systematic review and meta-analysis, we found a high prevalence of colorectal neoplasia among some populations. This indicates a need to expand CRC screening programs for these groups. The pooled prevalence estimates can be used as quality indicators for established CRC screening programs.

Towards risk-stratified colorectal cancer screening. Adding risk factors to the fecal immunochemical test: Evidence, evolution and expectations

With increasing incidence and mortality, colorectal cancer (CRC) is a growing health problem worldwide. An effective way to address CRC is by screening for fecal (occult) blood by the fecal immunochemical test (FIT). However, there is room for improvement since precursor lesions and CRC bleed intermittent and can therefore be missed by the FIT (false negatives) or, the detected blood did not result from precursor lesions or CRC (false positives). This review provides the latest evidence on risk prediction models using FIT combined with additional risk factors before colonoscopy, which risk factors to include and if these models will better discriminate between normal findings and CRC compared to the FIT-only. Many prediction models are known for CRC, but compared to the FIT, these are less effective in detecting CRC. The literature search resulted in 645 titles where 11 papers matched the inclusion criteria and were analyzed. Comparing the FIT-only with the risk prediction models for detecting CRC resulted in a significantly increased discrimination for the models. In addition, 2 different risk-stratification categories before colonoscopy were distinguished, namely the 1-model approach which combined risk factors with FIT results in a prediction model while the 2 step approach used risk factors apart from the FIT. Finally, combining FIT with CRC risk factors by means of a model before colonoscopy seems effective regarding discriminative power, however, more research is needed for validation combined with transparent and standardized reporting to improve quality assessment, for which suggestions are reported in this study.

Analysis of population-based colorectal cancer screening in Guangzhou, 2011-2015

Objective

To analyze the detection rates of colorectal cancer (CRC) and polyps by population‐based screening in Guangzhou.

Methods

From January 2011 to December 2015, the residents aged 30‐79 were selected for CRC screening. The residents were conducted Questionnaires and/or FOBT to assess high‐risk groups, the free colonoscopy examination was recommended, and the results were evaluated in detail.

Results

There were 98 927 residents involving screening, 5306 high‐risk residents identified (males 1859 and females 3447), and 4713 subjects underwent colonoscopy (males 1690 and females 3023). CRC was seen in 55 individuals (males 28 and females 27), and the detection rates in male were higher than in female (P = 0.019). And the detection rates increasing with age, for people over 60 years old, were obviously higher than those younger (x² = 18.64, P = 0.000924).

The polyps were seen in 1458 (30.94%) cases， and 1420 subjects received pathological examination (adenomas 971 and non‐adenomatous polyps 449). Advanced adenomas were seen in 462 cases (males 240 and females 222) and 509 cases of non‐advanced adenomas (males 255 and females 254). For advanced adenomas, the detection rates in male were higher than female (14.20% vs 7.34%, P = 2.64 × 10⁻¹⁴). For the detection rates of adenomas or advanced adenomas by age, the people over 40 years were higher than younger (20.91% vs 3.61% P = 7.87 × 10⁻⁶; 9.94% vs 2.41%, P = 0.009).

Conclusions

For Guangzhou residents, the detection rates of CRC and adenoma were 1.17% and 20.60%. The detection rates of CRC increasing with age, for people over 60 years old, were obviously higher than those younger. But for people over 40 years, the detection rate of adenoma and advanced adenoma was higher than younger. So for people over 40 years, the CRC screening is recommended.

A modified colorectal screening score for prediction of advanced neoplasia: A prospective study of 5744 subjects

BACKGROUND AND AIM

We validated a modified risk algorithm based on the Asia-Pacific Colorectal Screening (APCS) score that included body mass index (BMI) for prediction of advanced neoplasia.

METHODS

Among 5744 Chinese asymptomatic screening participants undergoing a colonoscopy in Hong Kong from 2008 to 2012, a random sample of 3829 participants acted as the derivation cohort. The odds ratios for significant risk factors identified by binary logistic regression analysis were used to build a scoring system ranging from 0 to 6, divided into "average risk" (AR): 0; "moderate risk" (MR): 1-2; and "high risk" (HR): 3-6. The other 1915 subjects formed a validation cohort, and the performance of the score was assessed.

RESULTS

The prevalence of advanced neoplasia in the derivation and validation cohorts was 5.4% and 6.0%, respectively (P = 0.395). Old age, male gender, family history of colorectal cancer, smoking, and BMI were significant predictors in multivariate regression analysis. A BMI cut-off at > 23 kg/m² had better predictive capability and lower number needed to screen than that of > 25 kg/m² . Utilizing the score developed, 8.4%, 57.4%, and 34.2% in the validation cohort were categorized as AR, MR, and HR, respectively. The corresponding prevalence of advanced neoplasia was 3.8%, 4.3%, and 9.3%. Subjects in the HR group had 2.48-fold increased prevalence of advanced neoplasia than the AR group. The c-statistics of the modified score had better discriminatory capability than that using predictors of APCS alone (c-statistics = 0.65 vs 0.60).

CONCLUSIONS

Incorporating BMI into the predictors of APCS score was found to improve risk prediction of advanced neoplasia and reduce colonoscopy resources.

Association between investigator-measured body-mass index and colorectal adenoma: a systematic review and meta-analysis of 168,201 subjects

The objective of this meta-analysis is to evaluate the odds of colorectal adenoma (CRA) in colorectal cancer screening participants with different body mass index (BMI) levels, and examine if this association was different according to gender and ethnicity. The EMBASE and MEDLINE were searched to enroll high quality observational studies that examined the association between investigator-measured BMI and colonoscopy-diagnosed CRA. Data were independently extracted by two reviewers. A random-effects meta-analysis was conducted to estimate the summary odds ratio (SOR) for the association between BMI and CRA. The Cochran’s Q statistic and I² analyses were used to assess the heterogeneity. A total of 17 studies (168,201 subjects) were included. When compared with subjects having BMI < 25, individuals with BMI 25–30 had significantly higher risk of CRA (SOR 1.44, 95% CI 1.30–1.61; I² = 43.0%). Subjects with BMI ≥ 30 had similarly higher risk of CRA (SOR 1.42, 95% CI 1.24–1.63; I² = 18.5%). The heterogeneity was mild to moderate among studies. The associations were significantly higher than estimates by previous meta-analyses. There was no publication bias detected (Egger’s regression test, p = 0.584). Subgroup analysis showed that the magnitude of association was significantly higher in female than male subjects (SOR 1.43, 95% CI 1.30–1.58 vs. SOR 1.16, 95% CI 1.07–1.24; different among different ethnic groups (SOR 1.72, 1.44 and 0.88 in White, Asians and Africans, respectively) being insignificant in Africans; and no difference exists among different study designs. In summary, the risk conferred by BMI for CRA was significantly higher than that reported previously. These findings bear implications in CRA risk estimation.

Increasing Incidence of Colorectal Cancer in Adolescents and Young Adults Aged 15-39 Years in Western Australia 1982-2007: Examination of Colonoscopy History

Aims

To examine trends in colorectal cancer (CRC) incidence and colonoscopy history in adolescents and young adults (AYAs) aged 15–39 years in Western Australia (WA) from 1982 to 2007.

Design

Descriptive cohort study using population-based linked hospital and cancer registry data.

Method

Five-year age-standardized and age-specific incidence rates of CRC were calculated for all AYAs and by sex. Temporal trends in CRC incidence were investigated using Joinpoint regression analysis. The annual percentage change (APC) in CRC incidence was calculated to identify significant time trends. Colonoscopy history relative to incident CRC diagnosis was examined and age and tumor grade at diagnosis compared for AYAs with and without pre-diagnosis colonoscopy. CRC-related mortality within 5 and 10 years of incident diagnosis were compared for AYAs with and without pre-diagnosis colonoscopy using mortality rate ratios (MRRs) derived from negative binomial regression.

Results

Age-standardized CRC incidence among AYAs significantly increased in WA between 1982 and 2007, APC = 3.0 (95% CI 0.7–5.5). Pre-diagnosis colonoscopy was uncommon among AYAs (6.0%, 33/483) and 71% of AYAs were diagnosed after index (first ever) colonoscopy. AYAs with pre-diagnosis colonoscopy were older at CRC diagnosis (mean 36.7 ± 0.7 years) compared to those with no prior colonoscopy (32.6 ± 0.2 years), p < 0.001. At CRC diagnosis, a significantly greater proportion of AYAs with pre-diagnosis colonoscopy had well-differentiated tumors (21.2%) compared to those without (5.6%), p = 0.001. CRC-related mortality was significantly lower for AYAs with pre-diagnosis colonoscopy compared to those without, for both 5-year [MRR = 0.44 (95% CI 0.27–0.75), p = 0.045] and 10-year morality [MRR = 0.43 (95% CI 0.24–0.83), p = 0.043].

Conclusion

CRC incidence among AYAs in WA has significantly increased over the 25-year study period. Pre-diagnosis colonoscopy is associated with lower tumor grade at CRC diagnosis as well as significant reduction in both 5- and 10-year CRC-related mortality rates. These findings warrant further research into the balance in benefits and harms of targeted screening for AYA at highest risk.

Long-term use of oral nucleos(t)ide analogues for chronic hepatitis B does not increase cancer risk - a cohort study of 44 494 subjects

BACKGROUND

Patients with chronic hepatitis B (CHB) need long-term antiviral treatment with nucleos(t)ide analogues (NA). Animal studies suggest that some NA may increase cancer risk, but human data are lacking.

AIM

To investigate cancer risks in patients with or without NA treatment.

METHODS

We conducted a territory-wide cohort study using the database from Hospital Authority in Hong Kong. The diagnosis of CHB and various malignancies was based on the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis codes between 2000 and 2012. Patients exposed to any of the oral NA for CHB were included. The primary outcome was incident cancers. A 3-year landmark analysis, with follow-up up to 7 years, was used to evaluate the relative risk of cancers in treated and untreated patients.

RESULTS

A total of 44 494 patients (39 712 untreated and 4782 treated) were included in the analysis. During 194 890 patient-years of follow-up, hepatocellular carcinoma developed in 402 (1.0%) untreated patients and 179 (3.7%) treated patients, while other cancers developed in 528 (1.3%) and 128 (2.7%) patients respectively. After propensity score weighting, treated patients had similar risks of all malignancies [weighted hazard ratio (wHR): 1.01, 95% CI: 0.82-1.25, P = 0.899], lung/pleural cancers (wHR: 0.82, 95% CI: 0.52-1.31, P = 0.409) and urinary/renal malignancies (wHR: 1.04, 95% CI: 0.38-2.81, P = 0.944) when compared with untreated patients.

CONCLUSIONS

Oral nucleos(t)ide analogue treatment does not appear to increase cancer risk in patients with chronic hepatitis B. Given the beneficial effect on liver outcomes, our data support the current practice of long-term anti-viral therapy.

An algorithm to predict advanced proximal colorectal neoplasia in Chinese asymptomatic population

This study aims to develop and validate a new algorithm that incorporates distal colonoscopic findings to predict advanced proximal neoplasia (APN) in a Chinese asymptomatic population. We collected age, gender, and colonoscopic findings from a prospectively performed colonoscopy study between 2013 and 2015 in a large hospital-based endoscopy unit in Shanghai, China. Eligible subjects were allocated to a derivation group (n = 3,889) and validation group (n = 1,944) by random sampling. A new index for APN and its cut-off level were evaluated from the derivation cohort by binary logistic regression. The model performance was tested in the validation cohort using area under the curve (AUC). Age, gender, and distal finding were found to be independent predictors of APN in the derivation cohort (p < 0.001). Subjects were categorized into Average Risk (AR) and High Risk (HR) based on a cut-off score of 2. The AUC of the derivation and validation cohorts were 0.801 (0.754-0.847) and 0.722 (0.649-0.794), respectively. In the validation cohort, those in the HR group had a 3.57 fold higher risk of APN when compared with the AR group (P < 0.001), requiring 18 (95% CI = 12-28) follow-up colonoscopies to detect 1 APN. This new clinical index is useful to stratify APN risk in Chinese population.

Mortality trends and risk of dying from colorectal cancer in the seven socioeconomic regions of Mexico, 2000-2012

BACKGROUND

In Mexico, there has been an upward trend in mortality rates from colorectal cancer (CRC) over the past three decades. This tumor is ranked among the ten most prevalent causes of morbidity from malignancies in Mexico.

AIMS

To determine the mortality trends by socioeconomic region and by state, and to establish the relative risk between both educational level and socioeconomic region with mortality from CRC within the time frame of 2000-2012.

MATERIALS AND METHODS

Records of mortality associated with colorectal cancer were obtained. Rates of mortality by state and by socioeconomic region were calculated, along with the strength of association (obtained through the Poisson regression) between both socioeconomic region and educational level and the mortality from CRC.

RESULTS

A total of 45,487 individuals died from CRC in Mexico from 2000 to 2012. Age-adjusted mortality rates per 100,000 inhabitants increased from 3.9 to 4.8. Baja California, Baja California Sur, and Sonora had the highest mortality from CRC. Individuals with no school or incomplete elementary school had a higher risk of dying from this cancer (RR of 3.57, 95% CI: 3.46-3.68). Region 7 had the strongest association with mortality from CRC (Mexico City: RR was 2.84, 95% CI: 2.39-3.37 [2000] and 3.32, 95% CI: 2.89-3.82 [2012]).

CONCLUSIONS

In Mexico, the age-adjusted mortality rates per 100,000 inhabitants that died from CRC increased from 3.9 to 4.8 in the study period, using the world population age distribution as the standard. Baja California, Baja California Sur, and Sonora had the highest mortality from CRC. Mexico City, which was socioeconomic region 7, had the strongest association with mortality from CRC.