Screening for Colorectal Neoplasms With New Fecal Occult Blood Tests: Update on Performance Characteristics

Effect of fecal immunochemical test cut-off levels on adenoma detection rate: a systematic review and meta-analysis

BACKGROUND

Adenoma detection rate (ADR) is higher after a positive fecal immunochemical test (FIT) compared to direct screening colonoscopy.

OBJECTIVE

This meta-analysis evaluated how ADR, the rates of advanced adenoma detection (AADR), colorectal cancer detection (CDR), and sessile serrated lesion detection (SSLDR) are affected by different FIT positivity thresholds.

METHODS

We searched MEDLINE, EMBASE, CINAHL, and EBM Reviews databases for studies reporting ADR, AADR, CDR, and SSLDR according to different FIT cut-off values in asymptomatic average-risk individuals aged 50-74 years old. Data were stratified according to sex, age, time to colonoscopy, publication year, continent, and FIT kit type. Study quality, heterogeneity, and publication bias were assessed.

RESULTS

Overall, 4280 articles were retrieved and fifty-eight studies were included (277,661 FIT-positive colonoscopies; mean cecal intubation 96.3%; mean age 60.8 years; male 52.1%). Mean ADR was 56.1% (95% CI 53.4 - 58.7%), while mean AADR, CDR, and SSLDR were 27.2% (95% CI 24.4 - 30.1%), 5.3% (95% CI 4.7 - 6.0%), and 3.0% (95% CI 1.7 - 4.6%), respectively. For each 20 μg Hb/g increase in FIT cut-off level, ADR increased by 1.54% (95% CI 0.52 - 2.56%, p < 0.01), AADR by 3.90% (95% CI 2.76 - 5.05%, p < 0.01) and CDR by 1.46% (95% CI 0.66 - 2.24%, p < 0.01). Many detection rates were greater amongst males and Europeans.

CONCLUSIONS

ADRs in FIT-positive colonoscopies are influenced by the adopted FIT positivity threshold, and identified targets, importantly, proved to be higher than most current societal recommendations.

A Review on Emerging Techniques for Diagnosis of Colorectal Cancer

Common detection methods in practice for diagnosing colorectal cancer (CRC) are painful and invasive leading to less participation of individuals for CRC diagnosis. Whereas, improved or enhanced imaging systems and other minimally invasive techniques with shorter detection times deliver greater detail and less discomfort in individuals. Thus, this review is a summary of the diagnostic tests, ranging from the simple potential use in developing a flexible CRC treatment to the patient's potential benefits in receiving less invasive procedures and the advanced treatments that might provide a better assessment for the diagnosis of CRC and reduce the mortality related to CRC.

Screening for Colorectal Cancer: The Role of Clinical Laboratories

BACKGROUND

Colorectal cancer (CRC) is a leading cause of cancer incidence and mortality. Screening can result in reductions in incidence and mortality, but there are many challenges to uptake and follow-up.

CONTENT

Here, we will review the changing epidemiology of CRC, including increasing trends for early and later onset CRC; evidence to support current and emerging screening strategies, including noninvasive stool and blood-based tests; key challenges to ensuring uptake and high-quality screening; and the critical role that clinical laboratories can have in supporting health system and public health efforts to reduce the burden of CRC on the population.

SUMMARY

Clinical laboratories have the opportunity to play a seminal role in optimizing early detection and prevention of CRC.

Reusing a prepaid health plan's fecal immunochemical tests for microbiome associations with colorectal adenoma

An altered colonic microbiota probably increases colorectal adenoma (CRA) and cancer (CRC) risk, but large, unbiased fecal collections are needed to examine the relationship of gut microbiota diversity and composition to colorectal carcinogenesis. This study assessed whether fecal immunochemical tests (FITs) from CRA/CRC screening may fulfill this requirement. Using FIT, self-collected by members of Kaiser Permanente Hawaii (KPH), as well as interspersed quality control (QC) specimens, DNA was extracted and amplified to generate 16S rRNA microbiome profiles rarified at 10,000 reads. CRA/CRC were diagnosed by colonoscopy and histopathology. Covariates were from electronic KPH records. Of 921 participants’ FIT devices, 538 (58%) yielded at least 10,000 rRNA reads and 1016 species-level variants mapped to 46 genera. Of the 538 evaluable participants, 63 (11.7%) were FIT-negative per protocol, and they were considered negative for CRA/CRC. Of the 475 FIT + participants, colonoscopy and pathologic review revealed that 8 (1.7%) had CRC, 71 (14.9%) had high-risk CRA, 107 (22.5%) had low-risk CRA, and 289 (60.8%) did not have CRA/CRC. Men were 2.27-fold [95% confidence interval (CI) 1.32–3.91] more likely than women to be FIT+ . Men also had 1.96-fold (CI 1.24–3.07) higher odds of low-risk CRA, with similar trends for high-risk CRA and CRC. CRA/CRC were not associated with overweight, obesity, diabetes, or antibiotic prescriptions in this study. QC analysis across 24 batches of FIT devices revealed QC outliers in four batches. With or without exclusion of the four QC-outlier batches, as well as lenient (1000-read) rarefaction, CRA/CRC had no consistent, statistically significant associations with fecal microbiome alpha diversity, beta diversity or genera relative abundance. CRA/CRC had expected associations with male sex but not with microbiome metrics. Fecal microbiome profiling using DNA extracted from at-home collected, re-used FIT devices is feasible, albeit with substantial challenges. Using FITs for prospective microbiome studies of CRA/CRC risk should consider the impact of the current findings on statistical power and requisite sample sizes.

Pooled rates of adenoma detection by colonoscopy in asymptomatic average-risk individuals with positive fecal immunochemical test: a systematic review and meta-analysis

BACKGROUND AND AIMS

Current adenoma detection rate (ADR) benchmarks for colonoscopy in individuals positive for a fecal immunochemical test (FIT) are ≥45% in men and ≥35% in women. These are based on weak, low-quality evidence. We performed a meta-analysis to ascertain the pooled ADR in FIT-positive colonoscopy.

METHODS

Major databases like PubMed, EMBASE, and Web of Science were searched in October 2021 for studies reporting on ADR of colonoscopy in a FIT-positive population. Meta-analysis was performed by standard methodology using the random-effects model. Heterogeneity was assessed by I² and 95% prediction interval statistics.

RESULTS

Thirty-four high-quality studies that included more than 6 million asymptomatic average-risk individuals were analyzed; 2,655,345 individuals completed a screening FIT test. The pooled FIT screening rate was 69.8% (95% CI, 62.8-76.1), the pooled FIT positivity rate was 5.4% (95% CI, 4.3-6.9), and the colonoscopy completion rate was 85% (95% CI, 82.8-86.9). The pooled ADR was 47.8% (95% CI, 44.1-51.6), pooled advanced ADR was 25.3% (95% CI, 22-29), and the pooled colorectal cancer detection rate was 5.1% (95% CI, 4.4-5.9). The pooled ADR in men was 58.3% (95% CI, 52.8-63.6) and in women was 41.9% (95% CI, 36.4-47.6). The pooled ADR with qualitative FIT assessment was 67.7% (95% CI, 50.7-81), with 1-stool sample FIT was 52.8% (95% CI, 48.8-56.8), and at a cutoff threshold of 100 ng hemoglobin/mL was 52.1% (95% CI, 47-57.1). Based on time-period cumulative analysis, the ADR improved over time from 30.5% (95% CI, 24.6-37.2) to 47.8% (95% CI, 44.1-51.6).

CONCLUSIONS

This meta-analysis supports the current ADR benchmarks for colonoscopy in FIT-positive individuals. Excellent pooled ADR parameters were demonstrated with qualitative assessment of 1 stool sample at a test cutoff value of 100 ng hemoglobin/mL, and ADR per endoscopist improved over time.

ASSESSING THE IMPACT OF PATENT ATTRIBUTES ON THE VALUE OF DISCRETE AND COMPLEX INNOVATIONS

This study assesses the degree to which the social value of patents can be connected to the private value of patents across discrete and complex innovation. The underlying theory suggests that the social value of cumulative patents is less related to the private value of patents. We use the patents applied between 1995 and 2002 and granted on or before December 2018 from the Indian Patent Office (IPO). Here, the patent renewal information is utilised as a proxy for the private value of the patent. We have used a variety of logit regression model for the impact assessment analysis. The results reveal that the technology classification (i.e., discrete vs. complex innovations) plays an important role in patent value assessment, and some technologies are significantly different than the others even within the two broader classifications. Moreover, the non-resident patents in India are more likely to have a higher value than the resident patents. According to the conclusions of this study, only a few technologies from the discrete and complex innovation categories have some private value. There is no evidence that patent social value indicators are less useful in complicated technical classes than in discrete ones.

Advances in tests for colorectal cancer screening and diagnosis

INTRODUCTION

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths globally. Nonetheless, with early detection of CRC or its precancerous lesions, mortality, and CRC incidence can be reduced. Although colonoscopy is currently the gold standard for CRC screening and diagnosis, its invasive nature, and troublesome bowel preparation deter patient participation. Therefore, there is a need to expand the use of noninvasive or minimally invasive methods to increase patient compliance.

AREAS COVERED

This review summarizes advances in different methods for CRC screening, including stool bacterial and metagenomic markers, fecal proteins, genetic and epigenetic markers in blood and stools, and imaging modalities. The cost-effectiveness of these methods is also discussed. FIT is more cost-effective compared to virtual colonoscopy, mSEPT9 test, and Multitarget Stool DNA test, while the cost-effectiveness of other noninvasive methods requires further evaluation.

EXPERT OPINION

Recent evidence has well demonstrated the usefulness of gut microbiome and certain fecal bacterial markers in the noninvasive diagnosis of CRC and its precancerous lesions. Many of the fecal biomarkers, from host cells or the gut environment, show better diagnostic sensitivity than FIT. New screening tests based on these fecal biomarkers can be expected to replace FIT with higher cost-effectiveness in the near future.

Clinical utility of a serum glycome analysis in patients with colorectal cancer

BACKGROUND AND AIM

Serum glycans are known to be good markers for the early diagnosis and prognostic prediction in many cancers. The aims of this study were to reveal the serum glycan changes comprehensively during the process of carcinogenesis from colorectal adenoma (CRA) to colorectal cancer (CRC) and to evaluate the usefulness of the glycan profiles as clinical markers for CRC.

METHODS

Serum samples were obtained from 80 histologically proven CRC and 36 CRA cases. The levels of glycans in the serum were examined with a comprehensive, quantitative, high-throughput unique glycome analysis, and their diagnostic and prognostic abilities were evaluated.

RESULTS

Among 34 stably detected glycans, nine were differentially expressed between CRC and CRA. Serum levels of hybrid type glycans were increased in patients with CRC compared with those with CRA (P < 0.001), and both hybrid-type and multi-antennary glycans were significantly increased in advanced cancer cases. The glycan, m/z 1914, showed the highest diagnostic value among the decreased glycans, whereas m/z 1708 showed the highest among the increased glycans. The glycan ratio m/z 1708/1914 showed a higher area under the receiver operating characteristic curve (0.889) than any other single glycan or conventional tumor marker, such as carcinoembryonic antigen (0.766, P = 0.040) and carbohydrate antigen 19-9 (0.615, P < 0.001). High m/z 1708/1914 was also correlated with an advanced cancer stage and short overall survival.

CONCLUSION

Serum glycans, especially the m/z 1708/1914 ratio, were useful for the diagnosis, staging, and prognosis prediction of CRC.

Screening for Colorectal Cancer Leading into a New Decade: The "Roaring '20s" for Epigenetic Biomarkers?

Colorectal cancer (CRC) has an important bearing (top five) on cancer incidence and mortality in the world. The etiology of sporadic CRC is related to the accumulation of genetic and epigenetic alterations that result in the appearance of cancer hallmarks such as abnormal proliferation, evasion of immune destruction, resistance to apoptosis, replicative immortality, and others, contributing to cancer promotion, invasion, and metastasis. It is estimated that, each year, at least four million people are diagnosed with CRC in the world. Depending on CRC staging at diagnosis, many of these patients die, as CRC is in the top four causes of cancer death in the world. New and improved screening tests for CRC are needed to detect the disease at an early stage and adopt patient management strategies to decrease the death toll. The three pillars of CRC screening are endoscopy, radiological imaging, and molecular assays. Endoscopic procedures comprise traditional colonoscopy, and more recently, capsule-based endoscopy. The main imaging modality remains Computed Tomography (CT) of the colon. Molecular approaches continue to grow in the diversity of biomarkers and the sophistication of the technologies deployed to detect them. What started with simple fecal occult blood tests has expanded to an armamentarium, including mutation detection and identification of aberrant epigenetic signatures known to be oncogenic. Biomarker-based screening methods have critical advantages and are likely to eclipse the classical modalities of imaging and endoscopy in the future. For example, imaging methods are costly and require highly specialized medical personnel. In the case of endoscopy, their invasiveness limits compliance from large swaths of the population, especially those with average CRC risk. Beyond mere discomfort and fear, there are legitimate iatrogenic concerns associated with endoscopy. The risks of perforation and infection make endoscopy best suited for a confirmatory role in cases where there are positive results from other diagnostic tests. Biomarker-based screening methods are largely non-invasive and are growing in scope. Epigenetic biomarkers, in particular, can be detected in feces and blood, are less invasive to the average-risk patient, detect early-stage CRC, and have a demonstrably superior patient follow-up. Given the heterogeneity of CRC as it evolves, optimal screening may require a battery of blood and stool tests, where each can leverage different pathways perturbed during carcinogenesis. What follows is a comprehensive, systematic review of the literature pertaining to the screening and diagnostic protocols used in CRC. Relevant articles were retrieved from the PubMed database using keywords including: "Screening", "Diagnosis", and "Biomarkers for CRC". American and European clinical trials in progress were included as well.

Promising Epigenetic Biomarkers for the Early Detection of Colorectal Cancer: A Systematic Review

In CRC, screening compliance is decreased due to the experienced discomfort associated with colonoscopy, although this method is the gold standard in terms of sensitivity and specificity. Promoter DNA methylation (hypomethylation or hypermethylation) has been linked to all CRC stages. Study objectives: to systematically review the current knowledge on approved biomarkers, reveal new potential ones, and inspect tactics that can improve performance. This research was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines; the risk of bias was evaluated using the revised Quality Assessment of Diagnostic Accuracy Studies criteria (QUADAS-2). The Web of Science® Core Collection, MEDLINE® and Scopus® databases were searched for original articles published in peer-reviewed journals with the specific keywords "colorectal cancer", "early detection", "early-stage colorectal cancer", "epigenetics", "biomarkers", "DNA methylation biomarkers", "stool or blood or tissue or biopsy", "NDRG4", "BMP3", "SEPT9", and "SDC2". Based on eligibility criteria, 74 articles were accepted for analysis. mSDC2 and mSEPT9 were frequently assessed in studies, alone or together as part of the ColoDefense panel test-the latter with the greatest performance. mBMP3 may not be an appropriate marker for detecting CRC. A panel of five methylated binding sites of the CTCF gene holds the promise for early-stage specific detection of CRC. CRC screening compliance and accuracy can be enhanced by employing a stool mt-DNA methylation test.

Colorectal Cancer Screening Outcomes of 2412 Prostate Cancer Patients Considered for Carbon Ion Radiotherapy

Colorectal cancer (CRC) screening is effective for detecting cancer in average-risk adults. For prostate cancer (PCa) patients considered for carbon ion radiotherapy (CIRT), pre-treatment CRC screening is performed empirically to avoid post-treatment colonoscopic manipulation. However, the outcomes of screening this population remain unclear. Here, we compared the outcomes of routine pre-CIRT CRC screening of 2412 PCa patients at average risk for CRC with data from two published datasets: the Japan National Cancer Registry (JNCR) and a series of 17 large-scale screening studies analyzing average-risk adults. The estimated prevalence rate was calculated using the pooled sensitivity elucidated by a previous meta-analysis. Consequently, 28 patients (1.16%) were diagnosed with CRC. CRC morbidity was significantly associated with high pre-treatment levels of prostate-specific antigen (p = 0.023). The screening positivity rate in this study cohort exceeded the annual incidence reported in the JNCR for most age brackets. Furthermore, the estimated prevalence rate in this study cohort (1.46%) exceeded that reported in all 17 large-scale studies, making the result an outlier (p = 0.005). These data indicate the possibility that the prevalence of CRC in PCa patients is greater than that in general average-risk adults, warranting further research in a prospective setting.

A Pilot Study Investigating the Expression Levels of Pluripotency-Associated Genes in Rectal Swab Samples for Colorectal Polyp and Cancer Diagnosis and Prognosis

Change in gene expression is inevitable in cancer development. With more studies demonstrating the contributions of cancer stem cells (CSCs) in colorectal cancer (CRC) development, this study is aimed at investigating whether rectal swab specimen serves as a tool for detection of dysregulation of CSC or stem cell (SC) markers and at evaluating its potential as a new promising screening method for high-risk patients. Expression levels of 15 pluripotency-associated genes were assessed by quantitative PCR in 53 rectal swab specimens referred for endoscopic screening. Dysregulated genes and joint panels based on such genes were examined for their diagnostic potentials for both polyp and CRC. Out of 15 genes, Oct4, CD26, c-MYC, and CXCR4 showed significantly differential expression among normal, polyp, and CRC patients. A panel of Oct4 and CD26 showed an AUC value of 0.80 (p = 0.003) in identifying CRC patients from polyp/normal subjects, with sensitivity and specificity of 84.6% and 69.2%. A panel of c-MYC and CXCR4 achieved CRC/polyp identification with an AUC value of 0.79 (p = 0.002), with a sensitivity of 82.8% and specificity of 80.0%. The sensitivity for polyp and CRC was 80.0% and 85.7%, respectively. Further analysis showed that higher c-MYC and CXCR4 level was detected in normal subjects who developed polyps after 5-6 years, in comparison with subjects with no lesion developed, and the AUC of the c-MYC and CXCR4 panel increased to 0.88 (p < 0.001), with sensitivity and specificity of 84.4% and 92.3%, respectively, when these patients were included in the polyp group. This study suggests that the Oct4 and CD26 panel is a promising biomarker for distinguishing CRC from normal and polyp patients, whereas the c-MYC and CXCR4 panel may identify polyp and CRC from normal individuals.

Age, male sex, smoking and metabolic syndrome as risk factors of advanced colorectal neoplasia for fecal immunochemical test negative patients

BACKGROUND

Fecal immunochemical test (FIT) is worldwide strategy for colorectal cancer screening. The subjects with negative FIT still have the risk of an advanced colorectal neoplasia (AN), including adenoma with villous histology, high grade dysplasia or larger than 1 cm in size, or adenocarcinoma. The study determined the risk factors associated with AN in FIT-negative subjects.

METHODS

The study included asymptomatic subjects who received health checkup colonoscopy and have provided FIT study within 6 months prior to colonoscopy. The risk factors to have AN in cases with negative FIT were analyzed. The numbers of colonoscopies needed to detect one AN were calculated for the subjects with different risk factors.

RESULTS

There were 1411 cases, 85 with positive FIT and 1326 with negative FIT within 6 months before colonoscopy. In FIT positive and FIT negative cases, 45.9% and 34.6% were found to have colorectal adenoma, while 20.2% and 4.6% had AN, respectively. The univariate and multivariate logistic regression analyses showed that age more than 50 years old, male sex, smoking history and metabolic syndrome were the significant risk factors to have AN in the FIT negative cases. For cases with negative FIT to have these risk factors, the number of colonoscopies needed to detect one AN was 3.7, lower than 4.5 of the cases with positive FIT.

CONCLUSION

For the cases with negative FIT, colonoscopy screening should be considered for those male patients over 50 years old, with a history of smoking and metabolic syndrome to detect AN.

Identifying Novel Biomarkers Ready for Evaluation in Low-Prevalence Populations for the Early Detection of Lower Gastrointestinal Cancers: A Systematic Review and Meta-Analysis

INTRODUCTION

Lower gastrointestinal (GI) cancers are a major cause of cancer deaths worldwide. Prognosis improves with earlier diagnosis, and non-invasive biomarkers have the potential to aid with early detection. Substantial investment has been made into the development of biomarkers; however, studies are often carried out in specialist settings and few have been evaluated for low-prevalence populations.

METHODS

We aimed to identify novel biomarkers for the detection of lower GI cancers that have the potential to be evaluated for use in primary care. MEDLINE, Embase, Emcare and Web of Science were systematically searched for studies published in English from January 2000 to October 2019. Reference lists of included studies were also assessed. Studies had to report on measures of diagnostic performance for biomarkers (single or in panels) used to detect colorectal or anal cancers. We included all designs and excluded studies with fewer than 50 cases/controls. Data were extracted from published studies on types of biomarkers, populations and outcomes. Narrative synthesis was used, and measures of specificity and sensitivity were meta-analysed where possible.

RESULTS

We identified 142 studies reporting on biomarkers for lower GI cancers, for 24,844 cases and 45,374 controls. A total of 378 unique biomarkers were identified. Heterogeneity of study design, population type and sample source precluded meta-analysis for all markers except methylated septin 9 (mSEPT9) and pyruvate kinase type tumour M2 (TuM2-PK). The estimated sensitivity and specificity of mSEPT9 was 80.6% (95% CI 76.6-84.0%) and 88.0% (95% CI 79.1-93.4%) respectively; TuM2-PK had an estimated sensitivity of 81.6% (95% CI 75.2-86.6%) and specificity of 80.1% (95% CI 76.7-83.0%).

CONCLUSION

Two novel biomarkers (mSEPT9 and TuM2-PK) were identified from the literature with potential for use in lower-prevalence populations. Further research is needed to validate these biomarkers in primary care for screening and assessment of symptomatic patients.

Screening for Colorectal Cancer: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Colorectal cancer (CRC) remains a significant cause of morbidity and mortality in the US.

OBJECTIVE

To systematically review the effectiveness, test accuracy, and harms of screening for CRC to inform the US Preventive Services Task Force.

DATA SOURCES

MEDLINE, PubMed, and the Cochrane Central Register of Controlled Trials for relevant studies published from January 1, 2015, to December 4, 2019; surveillance through March 26, 2021.

STUDY SELECTION

English-language studies conducted in asymptomatic populations at general risk of CRC.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently appraised the articles and extracted relevant study data from fair- or good-quality studies. Random-effects meta-analyses were conducted.

MAIN OUTCOMES AND MEASURES

Colorectal cancer incidence and mortality, test accuracy in detecting cancers or adenomas, and serious adverse events.

RESULTS

The review included 33 studies (n = 10 776 276) on the effectiveness of screening, 59 (n = 3 491 045) on the test performance of screening tests, and 131 (n = 26 987 366) on the harms of screening. In randomized clinical trials (4 trials, n = 458 002), intention to screen with 1- or 2-time flexible sigmoidoscopy vs no screening was associated with a decrease in CRC-specific mortality (incidence rate ratio, 0.74 [95% CI, 0.68-0.80]). Annual or biennial guaiac fecal occult blood test (gFOBT) vs no screening (5 trials, n = 419 966) was associated with a reduction of CRC-specific mortality after 2 to 9 rounds of screening (relative risk at 19.5 years, 0.91 [95% CI, 0.84-0.98]; relative risk at 30 years, 0.78 [95% CI, 0.65-0.93]). In observational studies, receipt of screening colonoscopy (2 studies, n = 436 927) or fecal immunochemical test (FIT) (1 study, n = 5.4 million) vs no screening was associated with lower risk of CRC incidence or mortality. Nine studies (n = 6497) evaluated the test accuracy of screening computed tomography (CT) colonography, 4 of which also reported the test accuracy of colonoscopy; pooled sensitivity to detect adenomas 6 mm or larger was similar between CT colonography with bowel prep (0.86) and colonoscopy (0.89). In pooled values, commonly evaluated FITs (14 studies, n = 45 403) (sensitivity, 0.74; specificity, 0.94) and stool DNA with FIT (4 studies, n = 12 424) (sensitivity, 0.93; specificity, 0.85) performed better than high-sensitivity gFOBT (2 studies, n = 3503) (sensitivity, 0.50-0.75; specificity, 0.96-0.98) to detect cancers. Serious harms of screening colonoscopy included perforations (3.1/10 000 procedures) and major bleeding (14.6/10 000 procedures). CT colonography may have harms resulting from low-dose ionizing radiation. It is unclear if detection of extracolonic findings on CT colonography is a net benefit or harm.

CONCLUSIONS AND RELEVANCE

There are several options to screen for colorectal cancer, each with a different level of evidence demonstrating its ability to reduce cancer mortality, its ability to detect cancer or precursor lesions, and its risk of harms.

Value of combined detection of IFOBT, tumor markers, and inflammatory markers in predicting occurrence of advanced colorectal adenoma

BACKGROUND

At present, there is a lack of effective, non-invasive screening tests for colorectal precancerous lesions. Identification of high-risk groups and multi-biomarker detection have become the trend of cancer and precancerous lesion screening. Inflammatory markers have been widely used in the diagnosis and prognosis of various tumors, but there are few studies on their diagnostic value in precancerous lesions.

AIM

To explore the predictive value of the general characteristics, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), CEA, CA199, and immunochemical fecal occult blood testing (IFOBT) in the occurrence of advanced colorectal adenoma.

METHODS

Two hundred and ninety-five cases of advanced colorectal adenomas confirmed by pathology and electronic colonoscopy at our hospital from 2014 to 2018 were retrospectively analyzed, and 448 cases of non-advanced adenomas in the same period were selected as a control group. The general clinical data of the patients, including basic characteristics (gender and age), living habits (smoking and drinking), and past history of disease (hypertension, coronary heart disease, diabetes), history of surgery (history of cholecystectomy or appendectomy), and laboratory examinations (NLR, PLR, CEA, CA199, and IFOBT) were collected. Measurement data were compared using t-test or Mann-Whitney U test, and count data were compared using χ² test. Statistically significant variables were included in binary logistic regression analysis. ROC curve was drawn to evaluate the predictive value of related indexes in the occurrence of advanced colorectal adenoma.

RESULTS

Multivariate logistic regression analysis demonstrated that age (odds ratio [OR] = 1.047, 95% confidence interval [CI]: 1.028-1.066, P = 0.000), smoking (OR = 1.880, 95%CI: 1.250-2.826, P = 0.002), diabetes (OR = 2.073, 95CI%: 1.216-3.535, P=0.007), previous cholecystectomy (OR = 9.206, 95CI%: 2.904-29.181, P = 0.000), IFOBT (OR = 7.681, 95%CI: 4.585-12.869, P = 0.000), CA199 (OR = 1.039, 95%CI: 1.018-1.059, P = 0.000), and NLR (OR = 1.706, 95%CI: 1.388-2.097, P = 0.000) were independent factors for advanced colorectal adenoma. ROC analysis showed that the areas under the ROC curves (AUCs) of IFOBT, CA199, and NLR in predicting advanced colorectal adenoma were 0.644 (95%CI: 0.602-0.686), 0.639 (95%CI: 0.598-0.679), and 0.645 (95%CI: 0.605-0.685), respectively. The optimal cutoff values for NLR and CA199 were 2.04 and 7.87 U/mL, respectively. The sensitivity and specificity of IFOBT, CA199, and NLR in predicting advanced colorectal adenoma were 34.6% and 94.2%, 53.9% and 66.1%, and 50.2% and 71.8%, respectively. The AUC of combination of the three biomarkers for the diagnosis of advanced adenoma was 0.752 (95%CI: 0.716-0.788), with a sensitivity of 52.9%and specificity of 82.8%. In the subgroup analysis, there were significant differences between the IFOBT(+) subgroup and IFOBT(-) subgroups with regard to tumor location (P = 0.048), diameter (P = 0.000), and differentiation(P = 0.000). There were also significant differences between the low NLR (< 2.04) subgroup and high NLR (≥ 2.04) subgroup with regard to gender (P = 0.004), tumor diameter (P = 0.028), and tumor differentiation (P = 0.000).

CONCLUSION

Advanced colorectal adenoma is associated with advanced age, smoking, diabetes, and previous cholecystectomy, and more attention should be paid to populations with these risk factors. IFOBT, NLR, and CA199 have appreciated diagnostic value for advanced colorectal adenoma, with the combination of all three having the highest diagnostic value.

ACG Clinical Guidelines: Colorectal Cancer Screening 2021

Colorectal cancer (CRC) is the third most common cancer in men and women in the United States. CRC screening efforts are directed toward removal of adenomas and sessile serrated lesions and detection of early-stage CRC. The purpose of this article is to update the 2009 American College of Gastroenterology CRC screening guidelines. The guideline is framed around several key questions. We conducted a comprehensive literature search to include studies through October 2020. The inclusion criteria were studies of any design with men and women age 40 years and older. Detailed recommendations for CRC screening in average-risk individuals and those with a family history of CRC are discussed. We also provide recommendations on the role of aspirin for chemoprevention, quality indicators for colonoscopy, approaches to organized CRC screening and improving adherence to CRC screening. CRC screening must be optimized to allow effective and sustained reduction of CRC incidence and mortality. This can be accomplished by achieving high rates of adherence, quality monitoring and improvement, following evidence-based guidelines, and removing barriers through the spectrum of care from noninvasive screening tests to screening and diagnostic colonoscopy. The development of cost-effective, highly accurate, noninvasive modalities associated with improved overall adherence to the screening process is also a desirable goal.

A New Method for the Detection of Colorectal Cancer and the Precancerous Lesions: Occult Blood Testing Combination with Promoter Methylation in the Fecal Sample

Background: Noninvasive stool-based DNA methylation testing emerges as a new approach for detecting colorectal cancer (CRC). However, its feasibility for early detection of CRC and precancerous lesions in the Chinese population remains inconclusive.

Methods: In this study, we establish a possibilities screening method (sDNA-FOBT) for detecting CRC and precancerous lesions (hyperplastic polyps [HP] and adenomas [AD]) and evaluate its detection performance in the Chinese population. This method combined a molecular assay of DNA methylation markers (BMP3, NDRG4, and SDC2) with the human hemoglobin test (FOBT) in stool samples.

Results: The sensitivity of sDNA-FOBT was 85.42% for CRC, 85.71% for AD, and 28.21% for HP, respectively, at the specificity of 92%. The diagnostic efficacy of sDNA-FOBT for detecting CRC and precancerous lesions was significantly higher than FOBT alone (sensitivity: 61.70% vs. 51.06%, P<0.01; AUC: 0.78 vs. 0.72, P<0.001), especially for CRC (AUC: 0.91 vs. 0.86, P<0.001) and AD (AUC: 0.91 vs. 0.75, P<0.05). No significant difference was observed between the detection sensitivity of sDNA-FOBT and the clinical variables. Notably, compared with FOBT, sDNA-FOBT was more effective in the detection of CRC and precancerous lesions in the patients aged >50 y (62.34% vs 54.55%, P<0.05).

Conclusion: Our results demonstrate that sDNA-FOBT is a promising method for screening CRC and precancerous lesions in the Chinese population. Further studies are required to validate the results in a larger sample capacity.

Faecal tests in the early detection of colorectal cancer

Colorectal cancer is one of the most common cancers in the world. It is the second most common cause of cancer deaths in both genders in Poland. Screening tests allow for early cancer detection, resulting in reduced mortality and better prognosis. Tests include a stool test for occult blood, checking for biomarkers in faeces, and stool DNA testing. Colonoscopy remains the gold standard in the diagnosis of cancer, both in Poland and around the world. To convince patients of the importance of such testing, it is necessary to have a wider knowledge of all the available diagnostic tests, to understand their advantages and disadvantages. This article will give descriptions of the respective tests and compare their effectiveness in the diagnosis of colorectal cancer.

Magnetic resonance spectroscopy and its application in colorectal cancer diagnosis and screening: A narrative review

There are several slightly invasive methods to detect colorectal carcinoma (CRC) including colonoscopy and sigmoidoscopy; but there is no noninvasive, accurate screening test. It is recommended to initiate screening at the age of 50 for non-familial CRC. Laboratory tests are routinely suggested if internal observation and imaging are recommended for further evaluation. Spectroscopic-based imaging, such as magnetic resonance spectroscopy (MRS) is an interesting and promising tool with the potential to be an alternative to some minimally invasive procedures, such as biopsy. Accordingly, MRS might be a suitable substitution for invasive methods, such as colonoscopy. This article aimed to review the studies that have evaluated the MRS technique as a screening tool in CRC.

Characteristics of Advanced Colorectal Cancer Detected by Fecal Immunochemical Test Screening in Participants with a Negative Result the Previous Year

BACKGROUND

There is sufficient evidence to show the mortality reduction effect of colorectal cancer (CRC) screening programs using the fecal occult blood test (FOBT). However, we see cases that are found to be advanced CRC despite yearly FOBT screening.

METHODS

The aim of this study was to investigate the characteristics of advanced CRC detected by a fecal immunochemical test (FIT) screening program in participants with a negative screening result the previous year, which we call "Negative advanced CRC". A total of 109,639 participants (10.0% required colonoscopy, of whom 76.9% received one) underwent a CRC screening program using a FIT from fiscal 2009 to 2017. Negative advanced CRC was compared with advanced CRC (First advanced CRC) found at the first visit in a person who had not had a FIT screening history for more than 3 years. In addition, we compared the characteristics of Negative advanced CRC with those of interval cancer: cancer cases detected after a negative screening result and before the date of the next recommended screening.

RESULTS

A total of 339 cases of CRC (175 male: 164 female, 173 early stage: 166 advanced stage) were detected in the nine-year CRC screening period. The rate of right-sided CRCs was significantly higher in female (P < 0.01), advanced stage (P < 0.01), negative result previous year (P < 0.01), and symptom-negative (P < 0.01) participants than in each counterpart, respectively. The ratio of female (22/35; 62.9%) patients in Negative advanced CRCs tended to be high compared with that (40/83; 48.2%) in First advanced CRCs (P = 0.145). Overall, 22 (62.9%) of 35 Negative advanced CRCs and 28 (33.7%) of 83 First advanced CRCs were located in the right-sided colon, and the rate was significantly higher in Negative advanced CRCs (P < 0.01). In addition, the frequency of female patients was significantly higher in right-sided Negative advanced CRCs than in right-sided First advanced CRCs (P = 0.03).

CONCLUSION

The characteristics of Negative advanced CRC cases (female and right-sided colon) were similar to those of interval cancer reported so far. In the future, it will be necessary to introduce a screening program that is highly sensitive to right-sided CRC.

Premature Fecal Immunochemical Testing in British Columbia Canada: a Retrospective Review of Physician and Screening Participant Characteristics

BACKGROUND

Colorectal cancer (CRC) screening is an evidence-based strategy to reduce CRC-related mortality.

OBJECTIVE

This study identifies physician and participant characteristics, as well as previous FIT values associated with premature FIT usage.

DESIGN

This is a retrospective review of all FITs ordered from January 1, 2016, until June 30, 2017. For each ordered FIT, the participant's chart was reviewed to identify if a previous FIT had occurred in the prior 21 months. A premature FIT was defined as an ordered test with a negative FIT in the preceding 21 months.

PARTICIPANTS

Screening participants were average risk for CRC, aged 50-74, and had a FIT ordered by their primary care provider in British Columbia, Canada.

MAIN MEASURES

The BC College of Physicians and Surgeons' database was used to identify the location of referring physician, date of graduation from medical school, and gender. The participant's age, gender, and value of previous FIT were recorded. Physician and participant variables and previous FIT value were examined with logistic regression to identify associations with premature FIT ordering.

KEY RESULTS

In total, 385,375 FITs were ordered during this period with 116,727 representing participants returning following a previous negative FIT. In total, 35,148 (30.1%) returned early for screening. Men were more likely to return early than women (OR 1.14; 95% CI 1.11-1.17; p < 0.0001). Male physicians were more likely to order premature FITs (OR 1.15; 95% CI 1.06-1.24; p < 0.0001). A higher quantitative FIT value (ng/mL) of the previous FIT was also associated with early screening (OR 1.11; 95% CI 1.09-1.14; < 0.0001).

CONCLUSIONS

This study found that approximately 30% of FIT tests, ordered for CRC screening, were ordered before they were due. This may lead to wasted resources, unnecessary participant stress, and unwarranted patient risk.

Colorectal cancer-screening program improves both short- and long-term outcomes: a single-center experience in Trieste

Screening programs (SC) have been proven to reduce both incidence and mortality of CRC. We retrospectively analyzed patients who underwent surgical treatment for CRC between 01/2011 and 01/2017. The current screening program in our region collects patients aged from 50 to 69. For this reason, out of a total of 600 patients, we compared 125 patients with CRC founded during the SC to 162 patients who presented with symptoms and were diagnosed between 50-69 years old (NO-SC). 45% patients in the SC group were diagnosed as AJCC stage I vs 27% patients in the NO-SC group; 14% vs 20% were stage II, 14% vs 26% were stage III, and 3% vs 14% were stage IV (p 0.002). We found a significant difference in surgical approach: 89% SC vs 56% NO-SC patients had laparoscopic surgery (p 0.002). In the NO-SC group, 16% patients underwent resection in an emergency setting. Only 5% patients in the SC group had postoperative complications vs 14% patients in the NO-SC group (p 0.03). We had a 2-year OS of 86%, being 95% in the SC group and 80% in the NO-SC group (p 0.002). Likewise, the whole 2-year DFS was 77%, whereas it was 90% in the SC group and 66% in the NO-SC group (p 0.002). Screening significantly improves early diagnosis and accelerated surgical treatment. We obtained earlier stages at diagnosis, a less invasive surgical approach, and lower rates of complications and emergency surgery, all this leading to an improvement in both OS and DFS.

Breath Volatile Organic Compound Profiling of Colorectal Cancer Using Selected Ion Flow-tube Mass Spectrometry

OBJECTIVE

BACKGROUND:: Breath VOCs have the potential to noninvasively diagnose cancer.

METHODS

Exhaled breath samples were collected using 2-L double-layered Nalophan bags, and were analyzed using selected-ion-flow-tube mass-spectrometry. Gold-standard test for comparison was endoscopy for luminal inspection and computed tomography (CT) to confirm cancer recurrence. Three studies were conducted: RESULTS:: CONCLUSION:: This study suggests the association of a single breath biomarker with the primary presence and recurrence of CRCa. Further multicenter validation studies are required to validate these findings.

Factors Associated With Colonoscopy Compliance Based on Health Belief Model in a Community-Based Colorectal Cancer Screening Program Shanghai, China

Screening can help early detection of colorectal cancer (CRC) in the general population. However, colonoscopy compliance in screening program is low in China. The study aimed to identify factors associated with colonoscopy compliance based on Health Belief Model (HBM). An investigation was conducted in Huangpu District, Shanghai in 2015. High-risk individuals of CRC received an in-person interview with physicians to fill out a questionnaire. The questionnaires assessing predictors of colonoscopy compliance were collected, and status of colonoscopy participation was determined. Univariate and multiple logistic regression analyses were conducted. Among 2,568 high-risk population (20.68%), 531 subjects underwent colonoscopy. Participants with both risk assessment and fecal immunochemical test positive were most likely to undergo colonoscopy. Based on HBM, colonoscopy compliance was positively associated with higher perceived severity (odds ratio [OR] = 1.05, 95% confidence interval [CI] = [1.00, 1.10]). Higher perceived barriers (OR = 0.97, 95% CI = [0.94, 0.99]), without prior colonoscopy (OR = 0.35, 95% CI = [0.26, 0.47]), not knowing anyone who underwent colonoscopy before (OR = 0.74, 95% CI = [0.58, 0.96]), without health-care provider recommendation on colonoscopy (OR = 0.58, 95% CI = [0.44, 0.77]), and without psychosocial support from someone for colonoscopy (OR = 0.27, 95% CI = [0.21, 0.35]) were shown to be associated with colonoscopy noncompliance. The colonoscopy compliance was low in this CRC screening program in Shanghai, China. The influencing factors were positive results in primary screening, perceived severity, perceived barriers, personal or others' experiences in colonoscopy, health-care provider recommendation, and psychosocial supports. Effective education campaign and facilitated communication between health-care providers and high-risk population were suggested in the future interventions.

Gel-Based Proteomics of Clinical Samples Identifies Potential Serological Biomarkers for Early Detection of Colorectal Cancer

The burden of colorectal cancer (CRC) is considerable-approximately 1.8 million people are diagnosed each year with CRC and of these about half will succumb to the disease. In the case of CRC, there is strong evidence that an early diagnosis leads to a better prognosis, with metastatic CRC having a 5-year survival that is only slightly greater than 10% compared with up to 90% for stage I CRC. Clearly, biomarkers for the early detection of CRC would have a major clinical impact. We implemented a coherent gel-based proteomics biomarker discovery platform for the identification of clinically useful biomarkers for the early detection of CRC. Potential protein biomarkers were identified by a 2D gel-based analysis of a cohort composed of 128 CRC and site-matched normal tissue biopsies. Potential biomarkers were prioritized and assays to quantitatively measure plasma expression of the candidate biomarkers were developed. Those biomarkers that fulfilled the preset criteria for technical validity were validated in a case-control set of plasma samples, including 70 patients with CRC, adenomas, or non-cancer diseases and healthy individuals in each group. We identified 63 consistently upregulated polypeptides (factor of four-fold or more) in our proteomics analysis. We selected 10 out of these 63 upregulated polypeptides, and established assays to measure the concentration of each one of the ten biomarkers in plasma samples. Biomarker levels were analyzed in plasma samples from healthy individuals, individuals with adenomas, CRC patients, and patients with non-cancer diseases and we identified one protein, tropomyosin 3 (Tpm3) that could discriminate CRC at a significant level (p = 0.0146). Our results suggest that at least one of the identified proteins, Tpm3, could be used as a biomarker in the early detection of CRC, and further studies should provide unequivocal evidence for the real-life clinical validity and usefulness of Tpm3.

Estimating the impact of insurance expansion on colorectal cancer and related costs in North Carolina: A population-level simulation analysis

Although screening is effective in reducing incidence, mortality, and costs of treating colorectal cancer (CRC), it remains underutilized, in part due to limited insurance access. We used microsimulation to estimate the health and financial effects of insurance expansion and reduction scenarios in North Carolina (NC). We simulated the full lifetime of a simulated population of 3,298,265 residents age-eligible for CRC screening (ages 50-75) during a 5-year period starting January 1, 2018, including polyp incidence and progression and CRC screening, diagnosis, treatment, and mortality. Insurance scenarios included: status quo, which in NC includes access to the Health Insurance Exchange (HIE) under the Affordable Care Act (ACA); no ACA; NC Medicaid expansion, and Medicare-for-all. The insurance expansion scenarios would increase percent up-to-date with screening by 0.3 and 7.1 percentage points for Medicaid expansion and Medicare-for-all, respectively, while insurance reduction would reduce percent up-to-date by 1.1 percentage points, compared to the status quo (51.7% up-to-date), at the end of the 5-year period. Throughout these individuals' lifetimes, this change in CRC screening/testing results in an estimated 498 CRC cases averted with Medicaid expansion and 6031 averted with Medicare-for-all, and an additional 1782 cases if health insurance gains associated with ACA are lost. Estimated cost savings - balancing increased CRC screening/testing costs against decreased cancer treatment costs - are approximately $30 M and $970 M for Medicaid expansion and Medicare-for-all scenarios, respectively, compared to status quo. Insurance expansion is likely to improve CRC screening both overall and in underserved populations while saving money, with the largest savings realized by Medicare.

Overestimated Sensitivity of Fecal Immunochemical Tests in Screening Cohorts With Registry-Based Follow-up

OBJECTIVES

Several recent studies have reported very high estimates of sensitivity and specificity of fecal immunochemical tests (FITs) at seemingly high levels of precision using registry-based follow-up of participants in very large FIT-based screening programs. We aimed to assess the validity of estimates of diagnostic performance parameters derived by this indirect approach.

METHODS

We modeled expected values of sensitivity and specificity of colorectal cancer detection in studies using the indirect approach and their deviation from true values under a broad range of plausible assumptions, and we compared these expected values with recently reported estimates of FIT sensitivity and specificity from such studies.

RESULTS

Using a sensitivity of 75% and specificity of 93.6% (from studies using a direct approach, i.e., colonoscopy follow-up of all participants), the indirect approach would be expected to yield sensitivities between 84.5% and 91.1% and specificities between 93.4% and 93.6% under a range of realistic assumptions regarding colonoscopic follow-up rates of positive FITs and clinical manifestation rates of preclinical colorectal cancer.

DISCUSSION

Very high sensitivities of FITs recently reported with seemingly very high levels of precision by several large-scale registry-based studies, which are in line with expected results based on our model calculations, are likely to be strongly overestimated and need to be interpreted with due caution.

Colorectal carcinoma screening: Established methods and emerging technology

Colorectal carcinoma screening programs have shown success in lowering both the incidence and mortality rate of colorectal carcinoma at a population level, in part because this carcinoma is relatively slow growing and has an identifiable premalignant lesion. Still, many patients do not undergo the recommended screening for colorectal carcinoma, and of those who do, a subset may be over- or under-diagnosed by the currently available testing methods. The primary purpose of this article is to review the data regarding currently available colorectal cancer screening modalities, which include fecal occult blood testing, direct colonic visualization, and noninvasive imaging techniques. In addition, readers will be introduced to a variety of biomarkers that may serve as stand-alone or adjunct tests in the future. Finally, there is a brief discussion of the current epidemiologic considerations that public health officials must address as they create population screening guidelines. The data we provide as laboratory physicians and scientists are critical to the construction of appropriate recommendations that ultimately decrease the burden of disease from colorectal carcinoma.

Scoring colorectal cancer risk with an artificial neural network based on self-reportable personal health data

Colorectal cancer (CRC) is third in prevalence and mortality among all cancers in the US. Currently, the United States Preventative Services Task Force (USPSTF) recommends anyone ages 50-75 and/or with a family history to be screened for CRC. To improve screening specificity and sensitivity, we have built an artificial neural network (ANN) trained on 12 to 14 categories of personal health data from the National Health Interview Survey (NHIS). Years 1997-2016 of the NHIS contain 583,770 respondents who had never received a diagnosis of any cancer and 1409 who had received a diagnosis of CRC within 4 years of taking the survey. The trained ANN has sensitivity of 0.57 ± 0.03, specificity of 0.89 ± 0.02, positive predictive value of 0.0075 ± 0.0003, negative predictive value of 0.999 ± 0.001, and concordance of 0.80 ± 0.05 per the guidelines of Transparent Reporting of Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) level 2a, comparable to current risk-scoring methods. To demonstrate clinical applicability, both USPSTF guidelines and the trained ANN are used to stratify respondents to the 2017 NHIS into low-, medium- and high-risk categories (TRIPOD levels 4 and 2b, respectively). The number of CRC respondents misclassified as low risk is decreased from 35% by screening guidelines to 5% by ANN (in 60 cases). The number of non-CRC respondents misclassified as high risk is decreased from 53% by screening guidelines to 6% by ANN (in 25,457 cases). Our results demonstrate a robustly-tested method of stratifying CRC risk that is non-invasive, cost-effective, and easy to implement publicly.

Incidence of faecal occult blood test interval cancers in population-based colorectal cancer screening: a systematic review and meta-analysis

OBJECTIVE

Faecal immunochemical tests (FITs) are replacing guaiac faecal occult blood tests (gFOBTs) for colorectal cancer (CRC) screening. Incidence of interval colorectal cancer (iCRC) following a negative stool test result is not yet known. We aimed to compare incidence of iCRC following a negative FIT or gFOBT.

DESIGN

We searched Ovid Medline, Embase, Cochrane Library, Science Citation Index, PubMed and Google Scholar from inception to 12 December 2017 for citations related to CRC screening based on stool tests. We included studies on FIT or gFOBT iCRC in average-risk screening populations. Main outcome was pooled incidence rate of iCRCs per 100 000 person-years (p-y). Pooled incidence rates were obtained by fitting random-effect Poisson regression models.

RESULTS

We identified 7 426 records and included 29 studies. Meta-analyses comprised data of 6 987 825 subjects with a negative test result, in whom 11 932 screen-detected CRCs and 5 548 gFOBT or FIT iCRCs were documented. Median faecal haemoglobin (Hb) positivity cut-off used was 20 (range 10-200) µg Hb/g faeces in the 17 studies that provided FIT results. Pooled incidence rates of iCRC following FIT and gFOBT were 20 (95% CI 14 to 29; I²=99%) and 34 (95% CI 20 to 57; I²=99%) per 100 000 p-y, respectively. Pooled incidence rate ratio of FIT versus gFOBT iCRC was 0.58 (95% CI 0.32 to 1.07; I²=99%) and 0.36 (95% CI 0.17 to 0.75; I²=10%) in sensitivity analysis. For every FIT iCRC, 2.6 screen-detected CRCs were found (ratio 1:2.6); for gFOBT, the ratio between iCRC and screen-detected CRC was 1:1.2. Age below 60 years and the third screening round were significantly associated with a lower iCRC rate.

CONCLUSION

A negative gFOBT result is associated with a higher iCRC incidence than a negative FIT. This supports the use of FIT over gFOBT as CRC screening tool.

Yield of repeat colonoscopy in asymptomatic individuals with a positive fecal immunochemical test and recent colonoscopy

BACKGROUND AND AIMS

A fecal immunochemical test (FIT) is often repeated annually, even after a recent colonoscopy. However, there are no published data on the proper approach to FIT-positive patients after a recent colonoscopy. We compared colorectal cancer (CRC) and advanced colorectal neoplasia (ACRN) prevalence based on the interval since the last colonoscopy.

METHODS

We reviewed asymptomatic screenees aged ≥50 years who underwent FIT and colonoscopy.

RESULTS

Of 2228 FIT-positive participants, 514 had a colonoscopy less than 3 years before (group 1), 427 had a colonoscopy had a colonoscopy 3 to 10 years before (group 2), and 1287 had a colonoscopy >10 years before or no colonoscopy (group 3). The prevalence of CRC in groups 1, 2, and 3 was 2.1%, 1.6%, and 7.2%, respectively, and that for ACRN was 10.9%, 12.6%, and 26.0%, respectively. Even after adjusting for confounders, CRC and ACRN detection rates in group 1 were lower than those in group 3 but not lower than those in group 2. Among 6135 FIT-negative participants, the prevalence of CRC in the 3 groups was .7%, .4%, and 3.4%, respectively, and that for ACRN was 6.0%, 6.1%, and 14.7%, respectively. CRC and ACRN detection rates were significantly higher in FIT-positive participants than in FIT-negative participants in all 3 groups.

CONCLUSIONS

In FIT-positive patients who underwent colonoscopy within the prior 3 years, CRC and ACRN prevalence was not low. Our findings support the U.S. Multi-Society Task Force on the CRC screening recommendation that repeat colonoscopy be offered to patients with positive FIT results and recent colonoscopy.

Quantitative immunochemical fecal occult blood test for neoplasia in colon cancer screening

OBJECTIVE

To investigate the performance of the quantitative immunochemical fecal occult blood test (qFIT) and to determine the association between the fecal hemoglobin (Hb) level and the location and size of adenomas and the stages of colorectal cancer (CRC).

METHODS

A total of 692 participants were included in the study. Their fecal Hb level was measured using an OC-SENSA MICRO qFIT. The colonoscopy results, including the location, size, and histological features of the adenomas, as well as the relationship between the Hb level and different characteristics were analyzed. Performance of the qFIT at various thresholds of fecal Hb levels was evaluated.

RESULTS

Advanced colorectal neoplasia (ACRN) was identified in 76 patients based on the colonoscopic and pathological examinations. Large adenomas (≥10 mm) had a higher fecal Hb level than small adenomas (<10 mm). Advanced adenomas located on the left side of the colon presented with a higher fecal Hb level than those on the right side (P = 0.022). Stage III-IV CRC patients had a significantly higher Hb level than stage I-II patients (P = 0.013). The sensitivity and specificity of qFIT for ACRN was 51.3% and 86.4%，respectively, with the best cut-off level of 400 ng/mL. The sensitivity and specificity for CRC was 61.0% and 89.1%, with the best cut-off level of 500 ng/mL.

CONCLUSIONS

qFIT has an acceptable sensitivity and specificity for ACRN detection. Furthermore, the qFIT results are associated with the location and size of adenomas as well as the grade of CRC.

Faecal immunochemical tests versus colonoscopy for post-polypectomy surveillance: an accuracy, acceptability and economic study

BACKGROUND

In the UK, patients with one or two adenomas, of which at least one is ≥ 10 mm in size, or three or four small adenomas, are deemed to be at intermediate risk of colorectal cancer (CRC) and referred for surveillance colonoscopy 3 years post polypectomy. However, colonoscopy is costly, can cause discomfort and carries a small risk of complications.

OBJECTIVES

To determine whether or not annual faecal immunochemical tests (FITs) are effective, acceptable and cost saving compared with colonoscopy surveillance for detecting CRC and advanced adenomas (AAs).

DESIGN

Diagnostic accuracy study with health psychology assessment and economic evaluation.

SETTING

Participants were recruited from 30 January 2012 to 30 December 2013 within the Bowel Cancer Screening Programme in England.

PARTICIPANTS

Men and women, aged 60-72 years, deemed to be at intermediate risk of CRC following adenoma removal after a positive guaiac faecal occult blood test were invited to participate. Invitees who consented and returned an analysable FIT were included.

INTERVENTION

We offered participants quantitative FITs at 1, 2 and 3 years post polypectomy. Participants testing positive with any FIT were referred for colonoscopy and not offered further FITs. Participants testing negative were offered colonoscopy at 3 years post polypectomy. Acceptibility of FIT was assessed using discussion groups, questionnaires and interviews.

MAIN OUTCOME MEASURES

The primary outcome was 3-year sensitivity of an annual FIT versus colonoscopy at 3 years for detecting advanced colorectal neoplasia (ACN) (CRC and/or AA). Secondary outcomes included participants' surveillance preferences, and the incremental costs and cost-effectiveness of FIT versus colonoscopy surveillance.

RESULTS

Of 8008 invitees, 5946 (74.3%) consented and returned a round 1 FIT. FIT uptake in rounds 2 and 3 was 97.2% and 96.9%, respectively. With a threshold of 40 µg of haemoglobin (Hb)/g faeces (hereafter referred to as µg/g), positivity was 5.8% in round 1, declining to 4.1% in round 3. Over three rounds, 69.2% (18/26) of participants with CRC, 34.3% (152/443) with AAs and 35.6% (165/463) with ACN tested positive at 40 µg/g. Sensitivity for CRC and AAs increased, whereas specificity decreased, with lower thresholds and multiple rounds. At 40 µg/g, sensitivity and specificity of the first FIT for CRC were 30.8% and 93.9%, respectively. The programme sensitivity and specificity of three rounds at 10 µg/g were 84.6% and 70.8%, respectively. Participants' preferred surveillance strategy was 3-yearly colonoscopy plus annual FITs (57.9%), followed by annual FITs with colonoscopy in positive cases (31.5%). FIT with colonoscopy in positive cases was cheaper than 3-yearly colonoscopy (£2,633,382), varying from £485,236 (40 µg/g) to £956,602 (10 µg/g). Over 3 years, FIT surveillance could miss 291 AAs and eight CRCs using a threshold of 40 µg/g, or 189 AAs and four CRCs using a threshold of 10 µg/g.

CONCLUSIONS

Annual low-threshold FIT with colonoscopy in positive cases achieved high sensitivity for CRC and would be cost saving compared with 3-yearly colonoscopy. However, at higher thresholds, this strategy could miss 15-30% of CRCs and 40-70% of AAs. Most participants preferred annual FITs plus 3-yearly colonoscopy. Further research is needed to define a clear role for FITs in surveillance.

FUTURE WORK

Evaluate the impact of ACN missed by FITs on quality-adjusted life-years.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN18040196.

FUNDING

National Institute for Health Research (NIHR) Health Technology Assessment programme, NIHR Imperial Biomedical Research Centre and the Bobby Moore Fund for Cancer Research UK. MAST Group Ltd provided FIT kits.

Clinical Proteomics in Colorectal Cancer, a Promising Tool for Improving Personalised Medicine

Colorectal cancer is the third most common and the fourth most lethal cancer worldwide. In most of cases, patients are diagnosed at an advanced or even metastatic stage, thus explaining the high mortality. The lack of proper clinical tests and the complicated procedures currently used for detecting this cancer, as well as for predicting the response to treatment and the outcome of a patient's resistance in guiding clinical practice, are key elements driving the search for biomarkers. In the present overview, the different biomarkers (diagnostic, prognostic, treatment resistance) discovered through proteomics studies in various colorectal cancer study models (blood, stool, biopsies), including the different proteomic techniques used for the discovery of these biomarkers, are reviewed, as well as the various tests used in clinical practice and those currently in clinical phase. These studies define the limits and perspectives related to proteomic biomarker research for personalised medicine in colorectal cancer.

Long-term performance of colorectal cancerscreening programmes based on the faecal immunochemical test

BACKGROUND

The long-term performance of colorectal cancer (CRC) screening programmes based on a 2-year faecal immunochemical test (FIT) is still unclear.

METHODS

In a sample of 50 to 69-year-olds repeatedly screened with the FIT (OC-Hemodia latex agglutination test; cut-off: 20 µg haemoglobin/g faeces), we examined: (1) the FIT positivity rate, the CRC and advanced adenoma detection rate and the FIT's positive predictive value (PPV) for advanced neoplasia, at each round of screening and (2) the cumulative CRC and advanced adenoma detection rate after five rounds of FIT.

RESULTS

Over 12 years (2002-2014), 123 347 individuals were administered the FIT up to six times, and 781 CRCs and 4713 advanced adenomas were diagnosed. The CRC and advanced adenoma detection rates declined substantially from the first to the third (rate ratio (RR) 0.25, 95% CI 0.20 to 0.32) and second (RR 0.51, 95% CI 0.47 to 0.56) rounds, respectively, and then remained stable. The PPV for advanced neoplasia dropped by 18% in the second round (RR 0.82, 95% CI 0.77 to 0.89), with no further reduction thereafter due to a concomitant decline in the FIT positivity rate (RR first to sixth rounds: 0.56, 95% CI 0.53 to 0.60).The cumulative CRC and advanced adenoma detection rates over five consecutive rounds were 8.5‰ (95% CI 7.8 to 9.2), and 58.9‰ (95% CI 56.9 to 61.0), respectively.

CONCLUSIONS

Repeated FIT significantly reduces the burden of colorectal disease while facilitating an efficient use of colonoscopy resources. The cumulative detection rate after five rounds of FIT is similar to primary screening with colonoscopy, supporting the need to account for the cumulative sensitivity of repeated FITs when evaluating the test's efficacy.

Divergent Long-Term Detection Rates of Proximal and Distal Advanced Neoplasia in Fecal Immunochemical Test Screening Programs: A Retrospective Cohort Study

BACKGROUND

Short-term studies have reported that the fecal immunochemical test (FIT) is less accurate in detecting proximal than distal colorectal neoplasia.

OBJECTIVE

To assess the long-term detection rates for advanced adenoma and colorectal cancer (CRC), according to anatomical location.

DESIGN

Retrospective study.

SETTING

Population-based, organized screening program in the Veneto region of Italy.

PARTICIPANTS

Persons aged 50 to 69 years who completed 6 rounds of FIT screening.

MEASUREMENTS

At each screening round, the detection rates for advanced adenoma and cancer, as well as the proportional interval cancer rate (PICR), were calculated by anatomical location (proximal colon, distal colon, or rectum).

RESULTS

Between 2002 and 2014, a total of 123 347 participants had 441 647 FITs. The numbers of advanced adenomas and cancer cases detected, respectively, were 1704 and 200 in the proximal colon, 3703 and 324 in the distal colon, and 1220 and 209 in the rectum. Although the detection rate for proximal colon cancer declined only from the first to the second screening round (0.63 to 0.36 per 1000 screenees), the rate for both distal colon and rectal cancer steadily decreased across 6 rounds (distal colon, 1.65 in the first round to 0.17 in the sixth; rectum, 0.82 in the first round to 0.17 in the sixth). Similar trends were found for advanced adenoma (proximal colon, 5.32 in the first round to 4.22 in the sixth; distal colon, 15.2 in the first round to 5.02 in the sixth). Overall, 150 cases of interval cancer were diagnosed. The PICR was higher in the proximal colon (25.2% [95% CI, 19.9% to 31.5%]) than the distal colon (6.0% [CI, 3.9% to 8.9%]) or rectum (9.9% [CI, 6.9% to 13.7%]).

LIMITATIONS

Participants with irregular attendance were censored. Those who had a false-positive result on a previous FIT but negative colonoscopy results were included in subsequent rounds.

CONCLUSION

This FIT-based, multiple-round, long-term screening program had a negligible reduction in detection rates for neoplastic lesions in the proximal versus the distal colon after the first round. This was related to a higher PICR in the proximal colon and suboptimal efficacy in preventing the age-related proximal shifting of CRC.

PRIMARY FUNDING SOURCE

None.

Effects of Organized Colorectal Cancer Screening on Cancer Incidence and Mortality in a Large Community-Based Population

BACKGROUND & AIMS

Little information is available on the effectiveness of organized colorectal cancer (CRC) screening on screening uptake, incidence, and mortality in community-based populations.

METHODS

We contrasted screening rates, age-adjusted annual CRC incidence, and incidence-based mortality rates before (baseline year 2000) and after (through 2015) implementation of organized screening outreach, from 2007 through 2008 (primarily annual fecal immunochemical testing and colonoscopy), in a large community-based population. Among screening-eligible individuals 51-75 years old, we calculated annual up-to-date status for cancer screening (by fecal test, sigmoidoscopy, or colonoscopy), CRC incidence, cancer stage distributions, and incidence-based mortality.

RESULTS

Initiation of organized CRC screening significantly increased the up-to-date status of screening, from 38.9% in 2000 to 82.7% in 2015 (P < .01). Higher rates of screening were associated with a 25.5% reduction in annual CRC incidence between 2000 and 2015, from 95.8 to 71.4 cases/100,000 (P < .01), and a 52.4% reduction in cancer mortality, from 30.9 to 14.7 deaths/100,000 (P < .01). Increased screening was initially associated with increased CRC incidence, due largely to greater detection of early-stage cancers, followed by decreases in cancer incidence. Advanced-stage CRC incidence rates decreased 36.2%, from 45.9 to 29.3 cases/100,000 (P < .01), and early-stage CRC incidence rates decreased 14.5%, from 48.2 to 41.2 cases/100,000 (P < .04).

CONCLUSIONS

Implementing an organized CRC screening program in a large community-based population rapidly increased screening participation to the ≥80% target set by national organizations. Screening rates were sustainable and associated with substantial decreases in CRC incidence and mortality within short time intervals, consistent with early detection and cancer prevention.

Single Nucleotide Polymorphism in SMAD7 and CHI3L1 and Colorectal Cancer Risk

Colorectal cancer (CRC) is one of the leading cancers throughout the world. It represents the third most common cancer and the fourth in mortality. Most of CRC are sporadic, arise with no known high-penetrant genetic variation and with no previous family history. The etiology of sporadic CRC is considered to be multifactorial and arises from the interaction of genetic variants of low-penetrant genes and environmental risk factors. The most common well-studied genetic variation is single nucleotide polymorphisms (SNPs). SNP arises as a point mutation. If the frequency of the sequence variation reaches 1% or more in the population, it is referred to as polymorphism, but if it is lower than 1%, the allele is typically considered as a mutation. Lots of SNPs have been associated with CRC development and progression, for example, genes of TGF-β1 and CHI3L1 pathways. TGF-β1 is a pleiotropic cytokine with a dual role in cancer development and progression. TGF-β1 mediates its actions through canonical and noncanonical pathways. The most important negative regulatory protein for TGF-β1 activity is termed SMAD7. The production of TGF-β can be controlled by another protein called YKL-40. YKL-40 is a glycoprotein with an important role in cancer initiation and metastasis. YKL-40 is encoded by the CHI3L1 gene. The aim of the present review is to give a brief introduction of CRC, SNP, and examples of some SNPs that have been documented to be associated with CRC. We also discuss two important signaling pathways TGF-β1 and CHI3L1 that influence the incidence and progression of CRC.

Positive predictive values of fecal immunochemical tests used in the STOP CRC pragmatic trial

Annual fecal immunochemical testing (FIT) is cost-effective for colorectal cancer (CRC) screening. However, FIT positivity rates and positive predictive value (PPV) can vary substantially, with false-positive (FP) results adding to colonoscopy burden without improving cancer detection. Our objective was to describe FIT PPV and the factors associated with FP results among patients undergoing CRC screening. In an ongoing pragmatic clinical trial of mailed-FIT outreach, clinics delivered one of three FIT brands (InSure, OC-Micro, and Hemosure). Patients who had a positive FIT result and a follow-up colonoscopy were included in this analysis (N = 1130). Patients' demographic and medical histories were abstracted from electronic health records (EHR). Associations with a FP result (ie, a positive FIT result with no evidence of advanced neoplasia during follow-up colonoscopy) were evaluated for FIT brand and patient factors using mixed-effects multivariable logistic regression. The mean proportion of FIT-positive results ranged from 8% in centers using the OC-Micro test to 21% for Hemosure. PPVs for advanced neoplasia were 0.30 to 0.17, respectively (P for χ2  = 0.08). In multivariable-adjusted models, use of Hemosure was associated with greater odds of a FP result than OC-Micro (OR = 2.00, 95% CI: 0.47-8.56) or InSure (OR = 1.72, 95% CI: 0.44-6.68). However, only female sex (OR = 1.58, 95% CI: 1.19-2.10) and history of a colorectal condition (OR = 2.17, 95% CI: 1.13-4.15) were significantly associated with FP. In conclusion, FIT positivity varied by brand, and FP results differed by patient factors available through the EHR. These results can be used to minimize the frequency of FP results, reducing patient distress and colonoscopy burden.

Can coffee or chewing gum decrease transit times in Colon capsule endoscopy? A randomized controlled trial

BACKGROUND

A high rate of complete colon capsule endoscopy (CCE) investigations is required for a more widespread use of CCE. The objective of this study was to assess if coffee or chewing gum can increase excretion of the colon capsule within battery life time (excretion rate).

METHODS

One hundred eighty six screening participants with a positive immunochemical fecal occult blood test were included in this single-centre randomized controlled trial with blinding of the investigators to the randomization. Participants received instant coffee, chewing gum or nothing in addition to the standard bowel preparation.

RESULTS

The intention was to include 57 participants in the coffee group, 61 in the chewing gum group and 60 in the control group, on 8 participants data were missing. A total of 165 participants were included in a per protocol analysis. Exclusion was due to not receiving the allocated intervention (8 coffee, 4 chewing gum) and technical failure of the capsule (1 coffee). The excretion rate was 58% in the coffee group (n = 48), 63% in the chewing gum group (n = 57) and 55% in the control group (n = 60, p > 0.2). Transit times were similar in all groups. The excretion rate was low in participants who had transit times over 10 h (14%). A strong correlation was found between adequate cleansing and excretion of the capsule. There were no serious adverse events related to the interventions or CCE investigations.

CONCLUSIONS

Chewing gum and coffee did not improve excretion rate in this study. An effect of chewing gum could not be proven, possibly due to sample size. Since chewing gum might improve excretion rates, is cheap and has no known side effects, it needs to be considered in future bowel preparation trials for CCE.

TRIAL REGISTRATION

NCT02303756 , registered on December 1st 2014.

Identifying quality improvement targets to facilitate colorectal cancer screening completion

The colorectal cancer (CRC) screening process involves multiple interfaces (communication exchanges and transfers of responsibility for specific actions) among primary care and gastroenterology providers, laboratory, and administrative staff. After a retrospective electronic health record (EHR) analysis discovered substantial clinic variation and low CRC screening prevalence overall in an urban, integrated safety-net system, we launched a qualitative analysis to identify potential quality improvement targets to enhance fecal immunochemical test (FIT) completion, the system's preferred screening modality. Here, we report examination of organization-, clinic-, and provider-level interfaces over a three-year period (December 2011-October 2014). We deployed in parallel 3 qualitative data collection methods: (1) structured observation (90+ hours, 10 sites); (2) document analysis (n > 100); and (3) semi-structured interviews (n = 41) and conducted iterative thematic analysis in which findings from each method cross-informed subsequent data collection. Thematic analysis was guided by a conceptual model and applied deductive and inductive codes. There was substantial variation in protocols for distributing and returning FIT kits both within and across clinics. Providers, clinic and laboratory staff had differing access to important data about FIT results based on clinical information system used and this affected results reporting. Communication and coordination during electronic referrals for diagnostic colonoscopy was suboptimal particularly for co-morbid patients needing anesthesia clearance. Our multi-level approach elucidated organizational deficiencies not evident by quantitative analysis alone. Findings indicate potential quality improvement intervention targets including: (1) best-practices implementation across clinics; (2) detailed communication to providers about FIT results; and (3) creation of EHR alerts to resolve pending colonoscopy referrals before they expire.

Stool Based Testing for Colorectal Cancer: an Overview of Available Evidence

PURPOSE OF REVIEW

The goal of this review is to summarize stool-based testing for colorectal cancer (CRC). The key questions answered in this review were the advantages and limitations of each available stool-based test for CRC and to examine their comparative efficacy.

RECENT FINDINGS

Guaiac-based fecal occult blood testing (gFOBT) is no longer a relevant test for CRC screening. fecal immunochemical testing (FIT) tests, especially quantitative assays, are clearly a reliable stool-based test. Multitarget DNA (mtsDNA) stool testing may represent a viable option as well, although cost and test characteristics are yet fully defined. FIT and mtsDNA represent the options for stool-based CRC screening. In larger screening centers, quantitative FIT assays represent an attractive option for stool-based testing. Qualitative FIT has applicability in smaller centers. Although a large validation trial showed promising results for mtsDNA, further head-to-head trials with FIT will help define the ultimate role of mtsDNA. Ultimately, however, the best test for CRC screening is the one performed stool-based CRC screening as an initial or alternative option can increase participation in CRC screening.

A Comparison of Fecal Immunochemical and High-Sensitivity Guaiac Tests for Colorectal Cancer Screening

OBJECTIVES

Annual testing using either a high-sensitivity guaiac fecal occult blood test (HS-gFOBT) or a fecal immunochemical test (FIT) is recommended for screening average-risk people for colorectal cancer. We compared the performance characteristics of the HS-gFOBT Hemoccult II SENSA and two FITs (InSure FIT and OC FIT-CHEK) for detecting advanced colorectal neoplasia.

METHODS

The study included 1,006 asymptomatic patients, aged 50-75 years, who were scheduled to receive a screening colonoscopy at gastroenterology practices in the Minneapolis and Indianapolis metropolitan areas. Each participant was asked to complete all three stool tests before their colonoscopy. Each test's performance characteristics were evaluated using the screening colonoscopic results as the reference standard.

RESULTS

Sensitivity for detecting advanced colorectal neoplasia was highest for InSure FIT (26.3%, 95% confidence interval (CI) 15.9-40.7), followed by OC FIT-CHEK (15.1%, 95% CI 6.7-26.1) and Hemoccult II SENSA (7.4%, 95% CI 1.9-17.0). InSure FIT was statistically significantly more sensitive than both OC FIT-CHEK (absolute difference in sensitivity=11.2%, 95% CI 0.4-24.2) and Hemoccult II SENSA (difference in sensitivity=18.9%, 95% CI 10.2-32.6). Specificities were relatively high for all tests (between 96.8% and 98.6%).

CONCLUSIONS

Our results suggest that some FITs are more sensitive than the HS-gFOBT Hemoccult II SENSA, but these results need to be confirmed in larger asymptomatic populations. Comparisons between the FITs examined in this study and other FITs are needed to determine the best tests for population screening.

Preliminary Results: Colorectal Cancer Screening Using Fecal Immunochemical Test (FIT) in a Thai Population Aged 45-74 Years: A Population-Based Randomized Controlled Trial

Objective:

The aim of this paper is to provide some details and the results to date of a colorectal cancer screening trial using a fecal immunochemical test (FIT).

Methods:

A population-based randomized controlled trial began in May, 2016. All people aged 45 to 74 years living in Nam Phong District, Khon Kaen Province, Thailand, and willing to participate are being recruited using an outreach method. Enrolled participants are randomly allocated by a computer-generated randomization program either to a study arm (receive sample kit for FIT) or to a control arm (no provision of kit). Positive FIT cases are subsequently confirmed by a colonoscopy examination, and negative FIT cases are re-tested with FIT every two years. The preliminary results to date were analysed using descriptive statistics.

Results:

A total of 1,060 enrolled participants provided a complete set of data. Of those randomly assigned to the study arm and tested by FIT, 92 (8.7%) were found to be positive, 39 (11.5%) males and 53 (7.4%) females. The f-Hb concentrations at the 75th, 90th and 95th percentiles for all age groups were higher in males than in females, and the distributions of f-Hb concentration varied with age, especially at the 95th percentile where f-Hb concentrations increased with age.

Conclusion:

The preliminary results of our screening trial have indicated that the prevalence of positive FIT cases is higher than in a similar recent and, at the time unique, previous study in Thailand. This finding is especially the case for males and those in the older age groups.

Screening of colorectal cancer: present and future

INTRODUCTION

Colorectal cancer (CRC) is the third most common cancer in males and second in females, and the fourth most common cause of cancer death worldwide. Currently, about 60-70% of diagnosed cases in symptomatic patients are detected at an advanced stage of disease. Earlier stage detection through the use of screening strategies would allow for better outcomes in terms of reducing the disease burden. Areas covered: The aim of this paper is to review the current published evidence from literature which assesses the performance and effectiveness of different screening tests for the early detection of CRC. Expert commentary: Adequate screening strategies can reduce CRC incidence and mortality. In the last few decades, several tests have been proposed for CRC screening. To date, there is still insufficient evidence to identify which approach is definitively superior, and no screening strategy for CRC can therefore be defined as universally ideal. The best strategy would be the one that can be economically viable and to which the patient can adhere best to over time. The latest guidelines suggest colonoscopy every 10 years or annual fecal immuno-chemical test (FIT) for people with normal risk, while for individuals with high risk or hereditary syndromes specific recommendations are provided.

Development of a multiplexed tumor-associated autoantibody-based blood test for the detection of colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignancies worldwide, and early diagnosis is vital to improving prognoses. We explored the diagnostic potential of a multiplex autoantibody panel as a biomarker for the detection of CRC by ELISA.

METHODS

In total, 192 serum samples (92 CRC and 100 matched controls) were tested against a panel of 12 tumor-associated antigens (TAAs): RPH3AL, RPL36, SLP2, p53, survivin, ANAXA4, SEC61B, CCCAP, NYCO16, NMDAR, PLSCR1, and HDAC5. Individual and combined autoantibody signatures were examined.

RESULTS

Compared to individual autoantibody markers, the combinations of TAAs provided better discrimination between tumorous and normal sera. The overall sensitivity of a selected panel of four antibodies (anti-SLP2, -p53, -SEC61B, and -PLSCR1) was 64.1%, with a specificity of 80% that increased to 83.7% when carcinoembryonic antigen (CEA) measurement was added. Furthermore, the sensitivity of the panel of four antibodies for early and advanced stages of CRC was 66.7% and 62%, increasing to 88.3% and 84%, respectively, when CEA was added.

CONCLUSIONS

We identified a panel of four antibodies as a promising diagnostic biomarker for the detection of CRC.

Colorectal cancer, screening and primary care: A mini literature review

Colorectal cancer (CRC) is a common health problem, representing the third most commonly diagnosed cancer worldwide and causing a significant burden in terms of morbidity and mortality, with annual deaths estimated at 700000. The western way of life, that is being rapidly adopted in many regions of the world, is a well discussed risk factor for CRC and could be targeted in terms of primary prevention. Furthermore, the relatively slow development of this cancer permits drastic reduction of incidence and mortality through secondary prevention. These facts underlie primary care physicians (PCPs) being assigned a key role in health strategies that enhance prevention and prompt diagnosis. Herein, we review the main topics of CRC in the current literature, in order to better understand its pathogenesis, risk and protective factors, as well as screening techniques. Furthermore, we discuss preventive and screening policies to combat CRC and the crucial role served by PCPs in their successful implementation. Relevant articles were identified through electronic searches of MEDLINE and through manual searches of reference lists.

"Finding the Right FIT": Rural Patient Preferences for Fecal Immunochemical Test (FIT) Characteristics

PURPOSE

Colorectal cancer (CRC) is the third leading cause of cancer death in the United States, yet 1 in 3 Americans have never been screened for CRC. Annual screening using fecal immunochemical tests (FITs) is often a preferred modality in populations experiencing CRC screening disparities. Although multiple studies evaluate the clinical effectiveness of FITs, few studies assess patient preferences toward kit characteristics. We conducted this community-led study to assess patient preferences for FIT characteristics and to use study findings in concert with clinical effectiveness data to inform regional FIT selection.

METHODS

We collaborated with local health system leaders to identify FITs and recruit age eligible (50 to 75 years), English or Spanish speaking community members. Participants completed up to 6 FITs and associated questionnaires and were invited to participate in a follow-up focus group. We used a sequential explanatory mixed-methods design to assess participant preferences and rank FIT kits. First, we used quantitative data from user testing to measure acceptability, ease of completion, and specimen adequacy through a descriptive analysis of 1) fixed response questionnaire items on participant attitudes toward and experiences with FIT kits, and 2) a clinical assessment of adherence to directions regarding collection, packaging, and return of specimens. Second, we analyzed qualitative data from focus groups to refine FIT rankings and gain deeper insight into the pros and cons associated with each tested kit.

FINDINGS

Seventy-six FITs were completed by 18 participants (Range, 3 to 6 kits per participant). Over half (56%, n = 10) of the participants were Hispanic and 50% were female (n = 9). Thirteen participants attended 1 of 3 focus groups. Participants preferred FITs that were single sample, used a probe and vial for sample collection, and had simple, large-font instructions with colorful pictures. Participants reported challenges using paper to catch samples, had difficulty labeling tests, and emphasized the importance of having care team members provide verbal instructions on test completion and follow-up support for patients with abnormal results. FIT rankings from most to least preferred were OC-Light, Hemosure iFOB Test, InSure FIT, QuickVue, OneStep+, and Hemoccult ICT.

CONCLUSIONS

FIT characteristics influenced patient's perceptions of test acceptability and feasibility. Health system leaders, payers, and clinicians should select FITs that are both clinically effective and incorporate patient preferred test characteristics. Consideration of patient preferences may facilitate FIT return, especially in populations at higher risk for experiencing CRC screening disparities.