Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: a joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology

Experience of a District General Hospital With a Diverse Community in Operated Colorectal Cancers According to Ethnic Background

Background

This study aimed to investigate disparities in colorectal cancer (CRC) patients’ demographics according to the five major ethnicities of patients living in the catchment area of North Middlesex Hospital.

Methodology

This retrospective study included CRC patients operated on between January 1, 2010, and December 31, 2014. Records dating to the end of the five-year follow-up were extracted anonymously from a database of CRC outcomes at the North Middlesex University Hospital NHS Trust. Comparisons were made according to ethnicity, patient demographics, type of presentation, cancer location, stage at diagnosis, recurrence, and mortality.

Results

A total of 176 adult patients were operated on for CRC between January 1, 2010, and December 31, 2014. The majority of the patients were referred as two-week wait target referrals. Emergency presentation of CRC was the highest in White non-UK patients. The White British Irish patients had their tumors mostly in the cecum, followed by the sigmoid colon, while the rectum followed by the sigmoid colon were the most common sites in the Black population. All study populations mainly presented with stage I disease, and the next highest incidence of cancers according to stage and ethnicity was stage IIIb in the Black population.

Conclusions

Differences in the ethnic background are important factors, especially in a diverse community, which can impact the age and mode of presentation of the disease, as well as the stage it starts to present. The location of the primary tumor, metastases, and recurrence sites are all affected by the ethnic background, which, subsequently, affect the survival of the patient.

Molecular methods for colorectal cancer screening: Progress with next-generation sequencing evolution

Currently, colorectal cancer (CRC) represents the third most common malignancy and the second most deadly cancer worldwide, with a higher incidence in developed countries. Like other solid tumors, CRC is a heterogeneous genomic disease in which various alterations, such as point mutations, genomic rearrangements, gene fusions or chromosomal copy number alterations, can contribute to the disease development. However, because of its orderly natural history, easily accessible onset location and high lifetime incidence, CRC is ideally suited for preventive intervention, but the many screening efforts of the last decades have been compromised by performance limitations and low penetrance of the standard screening tools. The advent of next-generation sequencing (NGS) has both facilitated the identification of previously unrecognized CRC features such as its relationship with gut microbial pathogens and revolutionized the speed and throughput of cataloguing CRC-related genomic alterations. Hence, in this review, we summarized the several diagnostic tools used for CRC screening in the past and the present, focusing on recent NGS approaches and their revolutionary role in the identification of novel genomic CRC characteristics, the advancement of understanding the CRC carcinogenesis and the screening of clinically actionable targets for personalized medicine.

Computer-aided detection, mucosal exposure device, their combination, and standard colonoscopy for adenoma detection: a randomized controlled trial

BACKGROUND AND AIMS

Computer-aided detection (CADe) and a mucosal exposure device can improve adenoma detection rate (ADR). Potential benefits of combining the 2 modalities have never been studied. This study aimed to compare ADR differences among CADe alone, endocuff-assisted colonoscopy (EAC) alone, and the combination of CADe and EAC (CADe+EAC) with standard colonoscopy.

METHODS

This prospective randomized controlled study included 1245 participants who underwent screening colonoscopy. Participants were randomized to CADe, EAC, CADe+EAC, and standard colonoscopy as a control. The primary outcome was ADR. Secondary outcomes were proximal ADR (pADR), advanced ADR (AADR), and the number of adenomas per colonoscopy (APCs).

RESULTS

ADRs from the control, CADe, EAC, and CADe+EAC groups were 41.9%, 52.2%, 54.0%, and 58.8%, respectively; pADRs were 25.2%, 33.3%, 34.9%, and 37.0%, respectively; AADRs were 7.7%, 8.3%, 8.3%, and 13.6%, respectively; and APCs were .76, 1.11, 1.18, and 1.31, respectively. Significant increases in ADR and pADR were observed between the intervention and control groups (P < .05 in all comparisons). The AADR was significantly higher only in the CADe+EAC group than in the control group (P = .02). The adjusted incidence rate ratios of APCs were significantly higher in the intervention groups versus the control group (P < .01 in all comparisons).

CONCLUSIONS

CADe+EAC significantly improve ADR and AADR over standard colonoscopy. However, although CADe or EAC alone can substantially increase the detection of adenomas, they do not lead to increased detection of advanced adenomas unless used in combination. (Clinical trial registration number: TCTR20200929003.).

Genome sequencing identifies complex structural MLH1 variant in unsolved Lynch syndrome

BACKGROUND

Lynch syndrome is one of the most common cancer predisposition syndromes. It is caused by inherited changes in the mismatch repair pathway. With current diagnostic approaches, a causative genetic variant can be found in less than 50% of cases. A correct diagnosis is important for ensuring that an appropriate surveillance program is used and that additional high-risk family members are identified.

METHODS

We used clinical genome sequencing on DNA from blood and subsequent transcriptome sequencing for confirmation. Data were analyzed using the megSAP pipeline and classified according to basic criteria in diagnostic laboratories. Segregation analyses in family members were conducted via breakpoint PCR.

RESULTS

We present a family with the clinical diagnosis of Lynch syndrome in which standard diagnostic tests, such as panel or exome sequencing, were unable to detect the underlying genetic variant. Genome sequencing in the index patient confirmed the previous diagnostic results and identified an additional complex rearrangement with intronic breakpoints involving MLH1 and its neighboring gene LRRFIP2. The previously undetected structural variant was classified as medically relevant. Segregation analysis in the family identified additional at-risk individuals which were offered intensified cancer screening.

DISCUSSION AND CONCLUSIONS

This case illustrates the advantages of clinical genome sequencing in detecting structural variants compared with current diagnostic approaches. Although structural variants are rare in Lynch syndrome families, they seem to be underreported, in part because of technical challenges. Clinical genome sequencing offers a comprehensive genetic characterization detecting a wide range of genetic variants.

Characteristics of adenomatous colorectal polyps among a Saudi population

Objectives

Colorectal cancer is a common cause of cancer-related mortality in KSA with a rising incidence. Although adenomatous polyps are well-recognized as precursors of colorectal cancer, local data are scarce. Therefore, in this study, we aimed to evaluate the characteristics of adenomatous colon polyps in the Saudi population.

Methods

We retrospectively reviewed the electronic databases of all patients who underwent colonoscopy for any indication between January 2015 and December 2019 at a tertiary care hospital. This study included adult patients who were found to have colorectal polyps with identified histopathology reports. We collected clinical and pathological data, including patient age, sex, and histopathological polyp characteristics. A p-value <0.05 was considered significant for descriptive and analytical statistics.

Results

A total of 184 patients with colorectal polyps with identified histopathology reports were included in the analysis. Of these, 130 (70.6%) patients were aged 50 years or older, and 135 (73.3%) were male. Among all polyps, 127 (69%) were adenomatous, 31 (16.8%) were hyperplastic, and 24 (13%) were inflammatory. For adenomatous polyps, 31 (24.4%) were observed in patients younger than 50 years, and high-grade dysplasia was observed in 23 (18%) polyps. Among patients with adenomatous polyps, the anatomical location was as follows: 27 (23%) in the cecum/ascending colon, 12 (9%) in the transverse colon, 45 (35%) in the descending/sigmoid colon, 25 (19%) in the rectum, and 18 (14%) at multiple sites. Age >50 years was significantly associated with adenomatous polyps (P = 0.03).

Conclusion

Approximately one-third of adenomatous polyps were detected proximal to the splenic flexure. Although adenomatous polyps were significantly associated with increasing age, 24% were observed in patients younger than 50 years of age. This finding supports the current recommendation to start screening at the age of 45.

Pre-clinical and clinical importance of miR-21 in human cancers: Tumorigenesis, therapy response, delivery approaches and targeting agents

The field of non-coding RNA (ncRNA) has made significant progress in understanding the pathogenesis of diseases and has broadened our knowledge towards their targeting, especially in cancer therapy. ncRNAs are a large family of RNAs with microRNAs (miRNAs) being one kind of endogenous RNA which lack encoded proteins. By now, miRNAs have been well-coined in pathogenesis and development of cancer. The current review focuses on the role of miR-21 in cancers and its association with tumor progression. miR-21 has both oncogenic and onco-suppressor functions and most of the experiments are in agreement with the tumor-promoting function of this miRNA. miR-21 primarily decreases PTEN expression to induce PI3K/Akt signaling in cancer progression. Overexpression of miR-21 inhibits apoptosis and is vital for inducing pro-survival autophagy. miR-21 is vital for metabolic reprogramming and can induce glycolysis to enhance tumor progression. miR-21 stimulates EMT mechanisms and increases expression of MMP-2 and MMP-9 thereby elevating tumor metastasis. miR-21 is a target of anti-cancer agents such as curcumin and curcumol and its down-regulation impairs tumor progression. Upregulation of miR-21 results in cancer resistance to chemotherapy and radiotherapy. Increasing evidence has revealed the role of miR-21 as a biomarker as it is present in both the serum and exosomes making them beneficial biomarkers for non-invasive diagnosis of cancer.

Colon Cancer Diagnosis Based on Machine Learning and Deep Learning: Modalities and Analysis Techniques

The treatment and diagnosis of colon cancer are considered to be social and economic challenges due to the high mortality rates. Every year, around the world, almost half a million people contract cancer, including colon cancer. Determining the grade of colon cancer mainly depends on analyzing the gland's structure by tissue region, which has led to the existence of various tests for screening that can be utilized to investigate polyp images and colorectal cancer. This article presents a comprehensive survey on the diagnosis of colon cancer. This covers many aspects related to colon cancer, such as its symptoms and grades as well as the available imaging modalities (particularly, histopathology images used for analysis) in addition to common diagnosis systems. Furthermore, the most widely used datasets and performance evaluation metrics are discussed. We provide a comprehensive review of the current studies on colon cancer, classified into deep-learning (DL) and machine-learning (ML) techniques, and we identify their main strengths and limitations. These techniques provide extensive support for identifying the early stages of cancer that lead to early treatment of the disease and produce a lower mortality rate compared with the rate produced after symptoms develop. In addition, these methods can help to prevent colorectal cancer from progressing through the removal of pre-malignant polyps, which can be achieved using screening tests to make the disease easier to diagnose. Finally, the existing challenges and future research directions that open the way for future work in this field are presented.

Development and validation of a population-based anatomical colorectal model for radiation dosimetry in late effects studies of survivors of childhood cancer

PURPOSE

The purposes of this study were to develop and integrate a colorectal model that incorporates anatomical variations of pediatric patients into the age-scalable MD Anderson Late Effects (MDA-LE) computational phantom, and validate the model for pediatric radiation therapy (RT) dose reconstructions.

METHODS

Colorectal contours were manually derived from whole-body non-contrast computed tomography (CT) scans of 114 pediatric patients (age range: 2.1-21.6 years, 74 males, 40 females). One contour was used for an anatomical template, 103 for training and 10 for testing. Training contours were used to create a colorectal principal component analysis (PCA)-based statistical shape model (SSM) to extract the population's dominant deformations. The SSM was integrated into the MDA-LE phantom. Geometric accuracy was assessed between patient-specific and SSM contours using several overlap metrics. Two alternative colorectal shapes were generated using the first 17 dominant modes of the PCA-based SSM. Dosimetric accuracy was assessed by comparing colorectal doses from test patients' CT-based RT plans (ground truth) with reconstructed doses for the mean and two alternative models in age-matched MDA-LE phantoms.

RESULTS

When using all 103 PCA modes, the mean (min-max) Dice similarity coefficient, distance-to-agreement and Hausdorff distance between the patient-specific and reconstructed contours for the test patients were 0.89 (0.85-0.91), 2.1 mm (1.7-3.0), and 8.6 mm (5.7-14.3), respectively. The average percent difference between reconstructed and ground truth mean and maximum colorectal doses for the mean (alternative 1, 2) model were 6.3% (8.1%, 6.1%) and 4.4% (4.3%, 4.7%), respectively.

CONCLUSIONS

We developed, validated and integrated a colorectal PCA-based SSM into the MDA-LE phantom and demonstrated its dosimetric performance for accurate pediatric RT dose reconstruction.

Awareness, Knowledge, Perceptions, and Attitudes towards Familial and Inherited Cancer

Background and Objectives: In 2020, the World Health Organization (WHO) reported 9.9 million deaths from cancer, with a mortality rate of 10.65%. Early detection of cancer can decrease mortality and increase the chance of cure. In Saudi Arabia, multiple studies were performed for awareness and attitudes toward cancer, but few studies evaluated the awareness of familial and inherited cancers. Materials and Methods: This is a cross-sectional observational survey of the awareness, knowledge, and attitudes of Saudi women toward familial and inherited cancers. The estimated sample size was 385. Questionnaires were distributed through social media platforms from 1 January 2021 to 22 January 2021. Results: Of the 385 participants, the majority have a bachelor’s degree. More than half (68.9%) know that family history is related to cancer, and approximately 57.2% are aware of genetic testing. The most common indication of genetic testing is premarital testing (18.5%). An inverse relationship is noted between the awareness of familial and inherited cancers and age (p = 0.003, CI = 0.723−0.938). However, awareness of inherited and familial cancer is positively associated with awareness of the association of genetic mutation to cancer (p = 0.013, CI = 1.080−1.921) and knowledge about genetic testing (p > 0.000, CI = 2.487−8.426). Conclusions: Our results reveal that Saudi women, especially older adults, have suboptimal knowledge about inherited and familial cancers, and poor attitudes toward genetic screening. We recommend increasing public awareness regarding risk factors and screening for inherited and familial cancers.

Identification of colorectal cancer using structured and free text clinical data

Colorectal cancer incidence has continually fallen among those 50 years old and over. However, the incidence has increased in those under 50. Even with the recent screening guidelines recommending that screening begins at age 45, nearly half of all early-onset colorectal cancer will be missed. Methods are needed to identify high-risk individuals in this age group for targeted screening. Colorectal cancer studies, as with other clinical studies, have required labor intensive chart review for the identification of those affected and risk factors. Natural language processing and machine learning can be used to automate the process and enable the screening of large numbers of patients. This study developed and compared four machine learning and statistical models: logistic regression, support vector machine, random forest, and deep neural network, in their performance in classifying colorectal cancer patients. Excellent classification performance is achieved with AUCs over 97%.

In vivo computer-aided diagnosis of colorectal polyps using white light endoscopy

Background and study aims  Artificial intelligence is currently able to accurately predict the histology of colorectal polyps. However, systems developed to date use complex optical technologies and have not been tested in vivo. The objective of this study was to evaluate the efficacy of a new deep learning-based optical diagnosis system, ATENEA, in a real clinical setting using only high-definition white light endoscopy (WLE) and to compare its performance with endoscopists. Methods  ATENEA was prospectively tested in real life on consecutive polyps detected in colorectal cancer screening colonoscopies at Hospital Clínic. No images were discarded, and only WLE was used. The in vivo ATENEA's prediction (adenoma vs non-adenoma) was compared with the prediction of four staff endoscopists without specific training in optical diagnosis for the study purposes. Endoscopists were blind to the ATENEA output. Histology was the gold standard. Results  Ninety polyps (median size: 5 mm, range: 2-25) from 31 patients were included of which 69 (76.7 %) were adenomas. ATENEA correctly predicted the histology in 63 of 69 (91.3 %, 95 % CI: 82 %-97 %) adenomas and 12 of 21 (57.1 %, 95 % CI: 34 %-78 %) non-adenomas while endoscopists made correct predictions in 52 of 69 (75.4 %, 95 % CI: 60 %-85 %) and 20 of 21 (95.2 %, 95 % CI: 76 %-100 %), respectively. The global accuracy was 83.3 % (95 % CI: 74%-90 %) and 80 % (95 % CI: 70 %-88 %) for ATENEA and endoscopists, respectively. Conclusion  ATENEA can accurately be used for in vivo characterization of colorectal polyps, enabling the endoscopist to make direct decisions. ATENEA showed a global accuracy similar to that of endoscopists despite an unsatisfactory performance for non-adenomatous lesions.

Colon Capsule Endoscopy in the Diagnosis of Colon Polyps: Who Needs a Colonoscopy?

Colon screening programs have reduced colon cancer mortality. Population screening should be minimally invasive, safe, acceptably sensitive, cost-effective, and scalable. The range of screening modalities include guaiac or immunochemical fecal occult blood testing and CT colonography and colonoscopy. A number of carefully controlled studies concur that second-generation capsule endoscopy has excellent sensitivity for polyp detection and a high negative predictive value. Colon capsules fulfill the screening expectation of safety, high sensitivity for polyp detection, and patient acceptance, and appear to straddle the divide between occult blood testing and colonoscopy. While meeting these criteria, there remains the challenges of scaling, capsule practitioner training, resource allocation, and implementing change of practice. Like CT colonography, capsule screening presents the clinician with a decision on the threshold for colonoscopy referral. Overall, colon capsules are an invaluable tool in polyp detection and colon screening and offer a filter that determines “who needs a colonoscopy?”.

Colorectal Cancer and Polyp Detection Using a New Preparation-Free, Colon-Scan Capsule: A Pilot Study of Safety and Patient Satisfaction

BACKGROUND

Current strategies to prevent colorectal cancer (CRC) vary considerably regarding safety, invasiveness, and patient satisfaction. A known deterrent for patients is the required bowel cleansing for colonoscopy. A new colon-scan capsule system is a unique preparation-free approach that provides structural information on colonic mucosa intended for detection of colorectal polyps and masses.

AIMS

The aim of this study was to determine safety and patient satisfaction with the colon-scan capsule.

METHODS

Prospective single-arm pilot study conducted at two tertiary care centers. Patients with a pre-scheduled colonoscopy for CRC screening or surveillance were included. Patients participating in this study underwent the colon-scan capsule and colonoscopy. Safety was defined by the occurrence of procedure or device-related adverse events. Satisfaction was based on survey questionnaires using a scoring system 1 (strongly disagree) to 5 (strongly agree). Patient satisfaction with the colon-scan capsule was compared to colonoscopy.

RESULTS

Forty patients were included (52.9 [5.7] years; 64.1% females). There were no serious adverse events and no occurrences of capsule retention. The most common (12.5%) complaint was self-limiting abdominal cramping. Satisfaction questionnaires were completed by more than 87% of patients, with patients likely to recommend the capsule (score 4.1 [1.03]) compared to colonoscopy (score 2.8 [1.2]), p = 0.001.

CONCLUSIONS

The new prepless colon-scan capsule system is an innovative, minimally invasive technology with demonstrated safety and high patient satisfaction. A multicenter pivotal study is planned to validate the performance, safety, and accuracy of polyp detection using the capsule system in comparison with colonoscopy.

Adherence to Recommendations for Repeat Surveillance After Publication of New Postpolypectomy Guidelines

Background and Aims

The 2012 and 2020 US Multi-Society Task Force postpolypectomy guidelines have recommended progressively longer surveillance intervals for patients with low-risk adenomas (LRAs). These guidelines require data from past colonoscopies. We examined the impact of the 2012 guidelines for second surveillance on clinical practice, including the availability of prior colonoscopy data, with the aim of informing the implementation of the 2020 guidelines.

Methods

We identified surveillance colonoscopies at Stanford Health Care and the Palo Alto Veterans Affairs Health Care System in 3 periods: preguideline (March-August 2012), postguideline (January-June 2013), and delayed postguideline (July-September 2017). We collected data on the most recent previous colonoscopy, findings at the study entry surveillance colonoscopy, and recommendations for subsequent surveillance.

Results

Among 977 patients, the most recent prior colonoscopy data were available in 78% of preguideline, 78% of postguideline, and 61% of delayed postguideline cases (P < .001). The fraction of surveillance colonoscopy reports that deferred recommendations awaiting pathology increased from 6% to 11% in preguideline and postguideline to 59% in delayed postguideline cases (P < .001). Overall adherence to guidelines for subsequent surveillance was similar in all 3 periods (54%-67%; P = .089). In the postguideline and delayed postguideline periods combined, a 10-year subsequent surveillance interval was recommended in 0 of 29 cases with LRA followed by normal surveillance colonoscopy.

Conclusion

In patients undergoing surveillance, prior colonoscopy data were not always available and recommendations were often deferred awaiting pathology. Adherence to subsequent surveillance guidelines was suboptimal, especially for LRA followed by normal colonoscopy. Strategies addressing these gaps are needed to optimize implementation of the updated 2020 postpolypectomy guidelines.

Peer evaluation and feedback for invasive medical procedures: a systematic review

BACKGROUND

There is significant variability in the performance and outcomes of invasive medical procedures such as percutaneous coronary intervention, endoscopy, and bronchoscopy. Peer evaluation is a common mechanism for assessment of clinician performance and care quality, and may be ideally suited for the evaluation of medical procedures. We therefore sought to perform a systematic review to identify and characterize peer evaluation tools for practicing clinicians, assess evidence supporting the validity of peer evaluation, and describe best practices of peer evaluation programs across multiple invasive medical procedures.

METHODS

A systematic search of Medline and Embase (through September 7, 2021) was conducted to identify studies of peer evaluation and feedback relating to procedures in the field of internal medicine and related subspecialties. The methodological quality of the studies was assessed. Data were extracted on peer evaluation methods, feedback structures, and the validity and reproducibility of peer evaluations, including inter-observer agreement and associations with other quality measures when available.

RESULTS

Of 2,135 retrieved references, 32 studies met inclusion criteria. Of these, 21 were from the field of gastroenterology, 5 from cardiology, 3 from pulmonology, and 3 from interventional radiology. Overall, 22 studies described the development or testing of peer scoring systems and 18 reported inter-observer agreement, which was good or excellent in all but 2 studies. Only 4 studies, all from gastroenterology, tested the association of scoring systems with other quality measures, and no studies tested the impact of peer evaluation on patient outcomes. Best practices included standardized scoring systems, prospective criteria for case selection, and collaborative and non-judgmental review.

CONCLUSIONS

Peer evaluation of invasive medical procedures is feasible and generally demonstrates good or excellent inter-observer agreement when performed with structured tools. Our review identifies common elements of successful interventions across specialties. However, there is limited evidence that peer-evaluated performance is linked to other quality measures or that feedback to clinicians improves patient care or outcomes. Additional research is needed to develop and test peer evaluation and feedback interventions.

Genome-Wide Association Study of Metachronous Colorectal Adenoma Risk among Participants in the Selenium Trial

Genetic variants related to colorectal adenoma may help identify those who are at highest risk of colorectal cancer development or illuminate potential chemopreventive strategies. The purpose of this genome-wide association study was to identify genetic variants that are associated with risk of developing a metachronous colorectal adenoma among 1,215 study participants of European descent from the Selenium Trial. Associations of variants were assessed with logistic regression analyses and validated in an independent case-control study population of 1,491 participants from the Colorectal Cancer Study of Austria (CORSA). No statistically significant genome-wide associations between any variant and metachronous adenoma were identified after correction for multiple comparisons. However, an intron variant of FAT3 gene, rs61901554, showed a suggestive association (P = 1.10 × 10-6) and was associated with advanced adenomas in CORSA (P = 0.04). Two intronic variants, rs12728998 and rs6699944 in NLRP3 were also observed to have suggestive associations with metachronous lesions (P = 2.00 × 10-6) in the Selenium Trial and were associated with advanced adenoma in CORSA (P = 0.03). Our results provide new areas of investigation for the genetic basis of the development of metachronous colorectal adenoma and support a role for FAT3 involvement in the Wnt/β-catenin pathway leading to colorectal neoplasia.Trial Registration number: NCT00078897 (ClinicalTrials.gov).

Prevalence and risk of colorectal polyps among the Korean population under 50 years

Colorectal cancer is a common cancer; generally, adults aged ≥ 50 years are screened using stool occult blood tests and colonoscopy. However, colorectal adenoma and cancer have been found in patients under the aged of 50, and studies on characteristics and risk factors in young patients are lacking. We evaluated the prevalence and risk factors of colorectal adenoma and cancer in young adults aged under 50 years. We retrospectively analyzed 570 individuals aged under 50 years who underwent colonoscopy at the Haeundae Paik Hospital, Korea, from January to June 2018. Logistic regression model was used to identify the risk factors for colorectal adenoma and colorectal cancer. The prevalence of colorectal adenoma in group of 19-29 years was 3.2% (1 of 31), 30-39 years was 13.8% (30 of 217) and in the group of 40-49 years was 21.1% (68 of 322) (P = .009). In multivariable analysis, age over 45 years (adjusted odds ratio [OR], 1.941; 95% confidence interval [CI], 1.187-3.172; P = .008) and male sex (adjusted OR, 1.711; 95% CI, 1.044-2.806; P = .033) were independent risk factors for colorectal neoplasia including cancer. The prevalence of colorectal adenoma increases as the age increased in young adults under 50 years of age, especially after the age of 45 years, the risk of colorectal neoplasia increases; hence, early screening should be considered before the age of 50 years.

Comparison of the morphology and histopathology of large nonpedunculated colorectal polyps in the rectum and colon: implications for endoscopic treatment

BACKGROUND AND AIMS

The risk of cancer in large nonpedunculated colorectal polyps ≥20 mm (LNPCPs) in the rectum relative to the remainder of the colon is unknown. We aimed to describe differences between rectal and colonic LNPCPs to better inform treatment decisions.

METHODS

Patients with LNPCPs referred to tertiary centers for endoscopic resection within a prospective, multicenter, observational cohort were evaluated. Data recorded were participant demographics, LNPCP location, morphology, resection modality, and histopathologic data. Multiple logistic regression analysis was used to identify those variables independently associated with rectal versus nonrectal location in the colon.

RESULTS

Patients with LNPCPs referred for endoscopic resection between July 2008 and July 2021 were included. Rectal LNPCPs (n = 618) were larger (median size, 40 mm vs 30 mm; P < .001) and more likely to be granular (79% vs 50%, P < .001) with a nodular component (53% vs 17%, P < .001) compared with nonrectal LNPCPs (n = 2787). Rectal LNPCPs were more likely to have tubulovillous histopathology (72% vs 47%, P < .001) and contain cancer (15% vs 6%, P < .001). After adjusting for the other features independently associated with location, cancer was more common in the rectum compared with the colon (odds ratio, 1.77; 95% confidence interval, 1.25-2.53).

CONCLUSIONS

This study suggests that compared with LNPCPs in the rest of the colon, rectal LNPCPs are more likely to be larger and contain more advanced pathology. These findings have implications for curative endoscopic resection techniques particularly where early cancer is present. (Clinical trial registration numbers: NCT01368289 and NCT02000141.).

Second Victim Experience and Perception Discordance of the Colonoscopic Perforation

BACKGROUND

Perforation is the most serious adverse event of colonoscopy, but rarely considered from the view of colonoscopists' second victim experience and perception discordance between colonoscopists and patients.

AIMS

We aimed to evaluate colonoscopists' second victim experience and the perception discordance between colonoscopists and patients for the colonoscopic perforation.

METHODS

A survey for colonoscopic perforation was performed for the colonoscopists and outpatients who visited the university hospital between February 1, 2020, and April 30, 2020. The questionnaire included questions regarding colonoscopists' satisfaction for the intervention strategies offered to patients and patient-colonoscopist perception on colonoscopic perforation. A modified Korean version of the "Second Victim Experience and Support Tool (K-SVEST)" was used to assess the second victim experiences and supportive resources for the colonoscopists.

RESULTS

Survey results from 160 colonoscopists and 165 patients were analyzed. The colonoscopists' satisfaction scores were higher for strategies related to sufficient explanation, empathy, courteous listening, and monetary compensation. The scores of the K-SVEST for the second victim experience were highest in psychological distress, followed by loss of professional self-efficacy, colleague support, physical distress, non-work-related support, institutional support, and turnover intentions/absenteeism. Significant patient-colonoscopist discordance was noted for the same colonoscopic perforation scenario on the judgment of medical error, health professionals' apology, monetary compensation, and criminal penalties for the colonoscopists.

CONCLUSIONS

Colonoscopists can suffer emotionally and physically from the second victim experience after colonoscopic perforation. In addition, the significant patient-colonoscopist discordance should be considered to make a better communication for the colonoscopic perforation.

The role of gut microbiota in the development of colorectal cancer: a review

PURPOSE

Colorectal cancer (CRC) is the cancer of the colon and rectum. Recent research has found a link between CRC and human gut microbiota. This review explores the effect of gut microbiota on colorectal carcinogenesis and the development of chemoresistance.

METHODS

A literature overview was performed to identify the gut microbiota species that showed altered abundance in CRC patients and the mechanisms by which some of them aid in the development of chemoresistance.

RESULTS

Types of gut microbiota present and methods of analyzing them were discussed. We observed that numerous microbiota showed altered abundance in CRC patients and could act as a biomarker for CRC diagnosis and treatment. Further, it was demonstrated that microbes also have a role in the development of chemoresistance by mechanisms like immune system activation, drug modification, and autophagy modulation. Finally, the key issue of the growing global problem of antimicrobial resistance and its relationship with CRC was highlighted.

CONCLUSION

This review discussed the role of gut microbiota dysbiosis on colorectal cancer progression and the development of chemoresistance.

Examining the Factors That Affect the Diagnosis of Patients with Positive Fecal Occult Blood Test Results

Due to the threat of colorectal cancer (CRC) to health, Taiwan included the fecal occult blood test (FOBT) under preventive health services in 2010. We examined the factors that affect the diagnosis of people with positive FOBT results. Data were retrospectively collected from the CRC screening database. In the model predicting factors that affect the diagnosis of 89,046 people with positive FOBT results, the risks of disease in the CRC group were lower in medical institutions that conducted follow-up examinations in regions such as Northern Taiwan compared to that in Eastern Taiwan (p = 0.013); they were lower in the age group of 50 to 65 years than those in the age group of 71 to 75 years (p < 0.001, p = 0.016), and lower in the outpatient medical units that conducted follow-up examinations than those in the inpatient medical units by 0.565 times (p < 0.001, 95% CI: 0.493−0.647). Factors affecting the diagnosis of patients with positive FOBT results were gender, the region of the medical institution, medical unit for follow-up examinations, age, screening site, family history, type of follow-up examinations, and follow-up time. Therefore, the identification of characteristics of patients with positive FOBT results and the promotion of follow-up examination are important prevention strategies for CRC.

TET2-BCLAF1 transcription repression complex epigenetically regulates the expression of colorectal cancer gene Ascl2 via methylation of its promoter

Ascl2 has been shown to be involved in tumorigenesis in colorectal cancer (CRC), although its epigenetic regulatory mechanism is largely unknown. Here, we found that methylation of the Ascl2 promoter (bp -1670 ∼ -1139) was significantly increased compared to the other regions of the Ascl2 locus in CRC cells and was associated with elevated Ascl2 mRNA expression. Furthermore, we found that promoter methylation was predictive of CRC patient survival after analyzing DNA methylation data, RNA-Seq data, and clinical data of 410 CRC patient samples from the MethHC database, the MEXPRESS database, and the Cbioportal website. Using the established TET methylcytosine dioxygenase 2 (TET2) knockdown and ectopic TET2 catalytic domain–expression cell models, we performed glucosylated hydroxymethyl–sensitive quatitative PCR (qPCR), real-time PCR, and Western blot assays to further confirm that hypermethylation of the Ascl2 promoter, and elevated Ascl2 expression in CRC cells was partly due to the decreased expression of TET2. Furthermore, BCLAF1 was identified as a TET2 interactor in CRC cells by LC-MS/MS, coimmunoprecipitation, immunofluorescence colocalization, and proximity ligation assays. Subsequently, we found the TET2–BCLAF1 complex bound to multiple elements around CCGG sites at the Ascl2 promoter and further restrained its hypermethylation by inducing its hydroxymethylation using chromatin immunoprecipitation-qPCR and glucosylated hydroxymethyl-qPCR assays. Finally, we demonstrate that TET2-modulated Ascl2-targeted stem gene expression in CRC cells was independent of Wnt signaling. Taken together, our data suggest an additional option for inhibiting Ascl2 expression in CRC cells through TET2–BCLAF1–mediated promoter methylation, Ascl2-dependent self-renewal of CRC progenitor cells, and TET2–BCLAF1–related CRC progression.

The potential of fecal microbiota and amino acids to detect and monitor patients with adenoma

The risk of recurrent dysplastic colonic lesions is increased following polypectomy. Yield of endoscopic surveillance after adenoma removal is low, while interval colorectal cancers occur. To longitudinally assess the dynamics of fecal microbiota and amino acids in the presence of adenomatous lesions and after their endoscopic removal. In this longitudinal case-control study, patients collected fecal samples prior to bowel preparation before scheduled colonoscopy and 3 months after this intervention. Based on colonoscopy outcomes, patients with advanced adenomas and nonadvanced adenomas (0.5-1.0 cm) who underwent polypectomy during endoscopy (n = 19) were strictly matched on age, body-mass index, and smoking habits to controls without endoscopic abnormalities (n = 19). Microbial taxa were measured by 16S RNA sequencing, and amino acids (AA) were measured by high-performance liquid chromatography (HPLC). Adenoma patients were discriminated from controls based on AA and microbial composition. Levels of proline (p = .001), ornithine (p = .02) and serine (p = .02) were increased in adenoma patients compared to controls but decreased to resemble those of controls after adenoma removal. These AAs were combined as a potential adenoma-specific panel (AUC 0.79(0.64-0.94)). For bacterial taxa, differences between patients with adenomas and controls were found (Bifidobacterium spp.↓, Anaerostipes spp.↓, Butyricimonas spp.↑, Faecalitalea spp.↑ and Catenibacterium spp.↑), but no alterations in relative abundance were observed after polypectomy. Furthermore, Faecalitalea spp. and Butyricimonas spp. were significantly correlated with adenoma-specific amino acids. We selected an amino acid panel specifically increased in the presence of adenomas and a microbial signature present in adenoma patients, irrespective of polypectomy. Upon validation, these panels may improve the effectiveness of the surveillance program by detection of high-risk individuals and determination of surveillance endoscopy timing, leading to less unnecessary endoscopies and less interval cancer.

Endoscopic Full-Thickness Resection for the Management of a Polyp in a Patient With Ulcerative Colitis

Endoscopic full-thickness resection (EFTR) is an endoscopic technique utilized to excise challenging gastrointestinal lesions. While the safety and efficacy of EFTR are well-documented in the general population, its utilization in patients with inflammatory bowel disease (IBD) has not been reported. Here, we present a patient with a longstanding history (more than 10 years) of ulcerative colitis (UC) who was recently found to have a large, fibrotic, non-lifting adenoma in her descending colon. After a multidisciplinary discussion, it was determined that the best way to remove the adenoma would be by EFTR. To our knowledge, this is the first reported case that details the use of EFTR in a patient with IBD. The procedure was successful, and the patient did not experience any complications during the procedure or upon clinical follow-up.

B7-H4 expression is upregulated by PKCδ activation and contributes to PKCδ-induced cell motility in colorectal cancer

Introduction

B7-H4 is overexpressed in colorectal cancer (CRC) and plays an important role in tumor growth and immunosuppression. However, the exact mechanism that regulates B7-H4 expression remains largely unknown. Here, we investigated whether protein kinase C δ (PKCδ) regulates the expression of B7-H4 in CRC.

Methods

By using immunohistochemical (IHC) and immunofluorescence (IF) staining, we analyzed the expression of B7-H4 and phospho-PKCδ (p-PKCδ) in 225 colorectal tumor samples and determined the clinical significance of the expression patterns. In vitro experiments were performed with the CRC cell lines HCT116 and SW620 to detect the effect of PKCδ activation on B7-H4 expression, and xenograft-bearing mice were treated with rottlerin to monitor the expression of B7-H4 and tumor metastasis.

Results

The B7-H4 expression level was significantly correlated with the p-PKCδ level (r = 0.378, P < 0.001) in tumor tissues. Coexpression of p-PKCδ and B7-H4 was significantly associated with moderate/poor differentiation (P = 0.024), lymph node metastasis (P = 0.001) and advanced Dukes’ stage (P = 0.002). Western blot analysis showed that Phorbol-12-Myristate-13-Acetate (TPA) increased B7-H4 expression in a concentration-dependent manner and that rottlerin abrogated the TPA-induced increase in B7-H4 expression. The protein levels of B7-H4 and p-STAT3 were significantly reduced by a PKCδ-specific siRNA. Moreover, the STAT3 inhibitor cryptotanshinone significantly decreased the B7-H4 protein level in CRC cells. Knockdown of B7-H4 or PKCδ suppressed cell migration and motility. Rottlerin also inhibited B7-H4 expression and tumor metastasis in vivo.

Conclusion

The B7-H4 expression level is significantly correlated with the p-PKCδ level and tumor metastasis in CRC samples. B7-H4 expression is upregulated by STAT3 activation via PKCδ and plays roles in PKCδ-induced cancer cell motility and metastasis, suggesting that the PKCδ/STAT3/B7-H4 axis may be a potential therapeutic target for CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02567-1.

Colorectal cancer screening by fecal immunochemical test or colonoscopy in France: how many people are actually covered? Focus on the Provence-Alpes-Côte d'Azur region

BACKGROUND

Colorectal cancer (CRC) screening with fecal immunochemical test (FIT) remains low in France, particularly in the Provence-Alpes-Côte-d'Azur (PACA) region. The aim of this study was to compare insured persons (50-74 years) who had FIT and/or colonoscopy in PACA with the general French population.

METHODS

FIT and colonoscopy rates were calculated according to SP-France and National Health Data System data.

RESULTS

The rate of FIT in 2016-2017 was lower in PACA than in France (25.6 vs. 29.1%, P < 0.001). Conversely, in 2013-2017, the rate of colonoscopy in the past 5 years was higher in PACA than in France (23.1 vs. 20.1%, P < 0.001). Total rate for FIT within 2 years and/or colonoscopy within 5 years was 46.0% in PACA vs. 46.5% in France (P < 0.001). Overuse was higher for diagnostic (1.21) than therapeutic colonoscopies (1.05). Therapeutic colonoscopy occurred more with FIT than without (47.88 vs. 38.7%, P < 0.001). According to USA criteria, persons with FIT within 2 years and/or sigmoidoscopy and/or colonoscopy within 10 years was 59.4% in PACA vs. 54.7% in France (P < 0.001).

CONCLUSION

Low participation in FIT in France must be improved to increase the rate of therapeutic colonoscopies and reduce the incidence of CRC. The higher colonoscopy rate in PACA could explain the lower CRC mortality. Efforts should be focused on the more than 40% of French insured who are not screened by either FIT or colonoscopy.

A multiple-dimension model for microbiota of patients with colorectal cancer from normal participants and other intestinal disorders

Gut microbiota is a primary driver of inflammation in the colon and is linked to early colorectal cancer (CRC) development. Thus, a novel and noninvasive microbiome-based model could promote screening in patients at average risk for CRC. Nevertheless, the relevance and effectiveness of microbial biomarkers for noninvasive CRC screening remains unclear, and researchers lack the data to distinguish CRC-related gut microbiome biomarkers from those of other common gastrointestinal (GI) diseases. Microbiome-based classification distinguishes patients with CRC from normal participants and excludes other CRC-relevant diseases (e.g., GI bleed, adenoma, bowel diseases, and postoperative). The area under the receiver operator characteristic curve (AUC) was 92.2%. Known associations with oral pathogenic features, benefits-generated features, and functional features of CRC were confirmed using the model. Our optimised prediction model was established using large-scale experimental population-based data and other sequence-based faecal microbial community data. This model can be used to identify the high-risk groups and has the potential to become a novel screening method for CRC biomarkers because of its low false-positive rate (FPR) and good stability. KEY POINTS: • A total of 5744 CRC and non-CRC large-scale faecal samples were sequenced, and a model was constructed for CRC discrimination on the basis of the relative abundance of taxonomic and functional features. • This model could identify high-risk groups and become a novel screening method for CRC biomarkers because of its low FPR and good stability. • The association relationship of oral pathogenic features, benefits-generated features, and functional features in CRC was confirmed by the study.

Role of Interleukin-1 in the pathogenesis of colorectal cancer: A brief look at anakinra therapy

Colorectal cancer (CRC) is known as one of the deadliest and most common cancers globally and causes nearly one million cancer deaths yearly. Like many malignancies, the immune system and its components play a crucial role in the pathogenesis of CRC. As multifunction mediators of the immune system, cytokines are involved in several inflammatory and anti-inflammatory responses. Interleukin-1 (IL-1) belongs to a family of 11 members and is involved in inflammatory responses. Beyond its biological role as a mediator of innate immune responses, it is also seen in chronic stress and inflammation and numerous pathological states. The role of IL-1 in malignancies can also be very significant because it has recently been shown that this cytokine can also be secreted from tumor cells and induce the recruitment of myeloid-derived immunosuppressive cells. As a result, the tumor microenvironment (TME) is affected and, despite being inflammatory, causes the onset and progression of tumor cells. Since surgery and chemotherapy are the first choices to treat patients with cancer, especially CRC, it is usually not well-prognosed, particularly in patients with metastatic lesions CRC. Therefore, targeted therapy may prolong the overall survival of CRC patients. Furthermore, evidence shows that anakinra has had satisfactory results in treating CRC. Therefore, this review summarized the role of IL-1 in the pathogenesis of CRC as well as immunotherapy based on inhibition of this cytokine in this type of cancer.

Higher Adenoma Detection Rates at Screening Associated With Lower Long-Term Colorectal Cancer Incidence and Mortality

BACKGROUND & AIMS

Detection and removal of adenomas reduces colorectal cancer (CRC) risk. The impact of adenoma detection rates (ADRs) on long-term CRC incidence and mortality is unknown. We investigated this using data from the UK Flexible Sigmoidoscopy Screening Trial.

METHODS

Of 167,882 UK Flexible Sigmoidoscopy Screening Trial participants, 40,085 were in the intervention arm and underwent flexible sigmoidoscopy screening at 13 trial centers. The median follow-up time was 17 years. At each center, 1 endoscopist performed most flexible sigmoidoscopies. Multivariable logistic regression was used to classify centers into high-, intermediate-, and low-detector groups based on their main endoscopist's ADR. We calculated the incidence and mortality of distal and all-site CRC, and estimated hazard ratios (HRs) with 95% CIs using Cox regression.

RESULTS

Five, 4, and 4 centers, respectively, were classified into the high-detector, intermediate-detector, and low-detector groups. The average ADRs in each respective group were 15%, 12%, and 9%. Distal CRC incidence and mortality were reduced among those screened compared with controls in all groups, and effects of screening varied significantly by detector ranking, with larger reductions in incidence and mortality seen in the high-detector group (incidence: HR, 0.34; 95% CI, 0.27-0.42; mortality: HR, 0.22, 95% CI, 0.13-0.37) than in the low-detector group (incidence: HR, 0.55; 95% CI, 0.44-0.68; mortality: HR, 0.54; 95% CI, 0.34-0.86). Similar results were observed for all-site CRC, with larger effects seen in the high-detector (incidence: HR, 0.58; 95% CI, 0.50-0.67; mortality: HR, 0.52; 95% CI, 0.39-0.69) than in the low-detector group (incidence: HR, 0.72; 95% CI, 0.61-0.85; mortality: HR, 0.68; 95% CI, 0.51-0.92), although the heterogeneity was not statistically significant.

CONCLUSIONS

Higher ADRs at screening provide greater long-term protection against CRC incidence and mortality. Isrctn.org, number: ISRCTN28352761.

The impact of face shields on the quality of gastrointestinal endoscopy during the COVID-19 pandemic

Background

Coronavirus disease 2019 (COVID-19) has become a global pandemic, with healthcare workers at a high risk of exposure. During this pandemic, endoscopists must wear personal protective equipment (PPE), including face shields, to prevent COVID-19 transmission; however, few studies have reported the impact of face shields on the quality of gastrointestinal (GI) endoscopy. We aimed to determine whether the use of PPE, including face shields, affected the quality of GI endoscopy during the COVID-19 pandemic.

Methods

The medical records of patients who had undergone screening or surveillance colonoscopy and gastric endoscopic submucosal dissection (ESD) at Dong-A University Hospital between June 2020 and March 2021 were retrospectively reviewed. Endoscopists wore isolation gowns, disposable gloves, and KF94 masks from June 2020 to October 2020. From November 2020, endoscopists also wore face shields. We compared GI endoscopy quality indicators between the first five months (no face shields) and the second five months (with face shields). In the non-face shield and face shield groups, we calculated the overall adenoma detection rates (ADRs), polyp detection rate (PDR), sessile serrated lesion detection rate (SSLDR), advanced neoplasia detection rate (ANDR), complete resection rate (CRR), number of polyps and/or adenomas per colonoscopy, and gastric ESD procedure time.

Results

In total, 1359 study patients had undergone screening or surveillance colonoscopy (face shield group, n = 679; non-face shield group, n = 680). No statistically significant between-group differences were observed (PDR, 49.04 vs. 52.50%, p = 0.202; ADR, 38.59 vs. 38.97%, p = 0.884; SSPDR, 1.91 vs. 1.32%, p = 0.388; ANDR, 3.98 vs. 3.97%, p = 0.991, respectively). No difference was found in colonoscopy quality indicators between patients examined by experienced and trainee endoscopists with and without face shields. Of 144 study patients who had undergone gastric ESD for gastric neoplasms, there were 72 patients in each group. No statistically significant differences were found in the CRR (94.44 vs 93.05%, p = 1.000) and procedure times (19.22 ± 9.33 vs. 19.03 ± 11.49, p = 0.911).

Conclusions

Wearing face shields during the COVID-19 pandemic did not affect the quality indicators for GI endoscopy.

Cost-Effectiveness of Community-to-Clinic Tailored Navigation for Colorectal Cancer Screening in an Underserved Population: Economic Evaluation Alongside a Group-Randomized Trial

PURPOSE

Although screening for colorectal cancer (CRC) lowers mortality and morbidity and is generally cost-effective, little is known about the cost-effectiveness of screening promotion.

DESIGN

Cost-effectiveness analysis alongside a group-randomized trial. Setting: Multicultural, underinsured communities in the Phoenix, Arizona, area.

SUBJECTS

English- or Spanish-speaking adults who were out of compliance for CRC screening guidelines.

INTERVENTION

All participants received community-based group education (GE), and the intervention group also received tailored community-to-clinic navigation (GE+TN).

MEASURES

Number of participants screened and costs of tailored navigation, clinic visits, and CRC screening tests.

ANALYSIS

Incremental cost per additional person screened from the perspective of the healthcare system with bootstrapped confidence intervals.

RESULTS

Community sites were recruited and randomized to GE (n = 120) and GE + TN (n = 119). Across these sites 1154 individuals were screened, 504 were eligible, and 345 attended the group education class (n = 134 GE; n = 211 GE + TN). Screening rates (26.5% GE + TN; 10.4% GE; 16.1% increase 95% CI: 7%, 23%) and costs per participant ($271 GE + TN; $167 GE; a net cost increase of $104 95% CI: $1, $189) were significantly higher in the intervention group. Incremental cost-effectiveness was $646 (95% CI: -$68, $953) per additional person screened.

CONCLUSION

Depending on the value placed on an additional person screened, the addition of community-to-clinic tailored navigation to a community-based CRC screening promotion program may be highly cost-effective.

Functional metabolome profiling may improve individual outcomes in colorectal cancer management implementing concepts of predictive, preventive, and personalized medical approach

Objectives

Colorectal cancer (CRC) is one of the most common solid tumors worldwide, but its diagnosis and treatment are limited. The objectives of our study were to compare the metabolic differences between CRC patients and healthy controls (HC), and to identify potential biomarkers in the serum that can be used for early diagnosis and as effective therapeutic targets. The aim was to provide a new direction for CRC predictive, preventive, and personalized medicine (PPPM).

Methods

In this study, CRC patients (n = 30) and HC (n = 30) were recruited. Serum metabolites were assayed using an ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) technology. Subsequently, CRC cell lines (HCT116 and HCT8) were treated with metabolites to verify their function. Key targets were identified by molecular docking, thermal shift assay, and protein overexpression/inhibition experiments. The inhibitory effect of celastrol on tumor growth was also assessed, which included IC50 analysis, nude mice xenografting, molecular docking, protein overexpression/inhibition experiments, and network pharmacology technology.

Results

In the CRC group, 15 serum metabolites were significantly different in comparison with the HC group. The level of glycodeoxycholic acid (GDCA) was positively correlated with CRC and showed high sensitivity and specificity for the clinical diagnostic reference (AUC = 0.825). In vitro findings showed that GDCA promoted the proliferation and migration of CRC cell lines (HCT116 and HCT8), and Poly(ADP-ribose) polymerase-1 (PARP-1) was identified as one of the key targets of GDCA. The IC50 of celastrol in HCT116 cells was 121.1 nM, and the anticancer effect of celastrol was supported by in vivo experiments. Based on the potential of GDCA in PPPM, PARP-1 was found to be significantly correlated with the anticancer functions of celastrol.

Conclusion

These findings suggest that GDCA is an abnormally produced metabolite of CRC, which may provide an innovative molecular biomarker for the predictive identification and targeted prevention of CRC. In addition, PARP-1 was found to be an important target of GDCA that promotes CRC; therefore, celastrol may be a potential targeted therapy for CRC via its effects on PARP-1. Taken together, the pathophysiology and progress of tumor molecules mediated by changes in metabolite content provide a new perspective for predictive, preventive, and personalized medical of clinical cancer patients based on the target of metabolites in vivo.Clinical trials registration number: ChiCTR2000039410.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-021-00269-8.

An Adaptive Learning Model for Multiscale Texture Features in Polyp Classification via Computed Tomographic Colonography

Objective: As an effective lesion heterogeneity depiction, texture information extracted from computed tomography has become increasingly important in polyp classification. However, variation and redundancy among multiple texture descriptors render a challenging task of integrating them into a general characterization. Considering these two problems, this work proposes an adaptive learning model to integrate multi-scale texture features. Methods: To mitigate feature variation, the whole feature set is geometrically split into several independent subsets that are ranked by a learning evaluation measure after preliminary classifications. To reduce feature redundancy, a bottom-up hierarchical learning framework is proposed to ensure monotonic increase of classification performance while integrating these ranked sets selectively. Two types of classifiers, traditional (random forest + support vector machine)- and convolutional neural network (CNN)-based, are employed to perform the polyp classification under the proposed framework with extended Haralick measures and gray-level co-occurrence matrix (GLCM) as inputs, respectively. Experimental results are based on a retrospective dataset of 63 polyp masses (defined as greater than 3 cm in largest diameter), including 32 adenocarcinomas and 31 benign adenomas, from adult patients undergoing first-time computed tomography colonography and who had corresponding histopathology of the detected masses. Results: We evaluate the performance of the proposed models by the area under the curve (AUC) of the receiver operating characteristic curve. The proposed models show encouraging performances of an AUC score of 0.925 with the traditional classification method and an AUC score of 0.902 with CNN. The proposed adaptive learning framework significantly outperforms nine well-established classification methods, including six traditional methods and three deep learning ones with a large margin. Conclusions: The proposed adaptive learning model can combat the challenges of feature variation through a multiscale grouping of feature inputs, and the feature redundancy through a hierarchal sorting of these feature groups. The improved classification performance against comparative models demonstrated the feasibility and utility of this adaptive learning procedure for feature integration.

Endoscopic Management of Complex Colorectal Polyps: Current Insights and Future Trends

Most colorectal cancers arise from adenomatous polyps and sessile serrated lesions. Screening colonoscopy and therapeutic polypectomy can potentially reduce colorectal cancer burden by early detection and removal of these polyps, thus decreasing colorectal cancer incidence and mortality. Most endoscopists are skilled in detecting and removing the vast majority of polyps endoscopically during a routine colonoscopy. Polyps can be considered “complex” based on size, location, morphology, underlying scar tissue, which are not amenable to removal by conventional endoscopic polypectomy techniques. They are technically more challenging to resect and carry an increased risk of complications. Most of these polyps were used to be managed by surgical intervention in the past. Rapid advancement in endoscopic resection techniques has led to a decreasing role of surgery in managing these complex polyps. These endoscopic resection techniques do require an expert in the field and advanced equipment to perform the procedure. In this review, we discuss various advanced endoscopic techniques for the management of complex polyps.

Colonic Chicken Skin Mucosa Surrounding Colon Polyps Is an Endoscopic Predictive Marker for Colonic Neoplastic Polyps

Background/Aims

Narrow band imaging provides an accurate diagnosis of colonic polyps. However, these diagnostic modalities are not used as standard endoscopic tools in most institutions. This study aims to investigate whether the chicken skin mucosa (CSM) surrounding the colon polyp yields additional information about colorectal polyps, including histological differentiation of neoplastic and non-neoplastic polyps, under conventional white light colonoscopy.

Methods

This study prospectively observed 173 patients who underwent endoscopic polypectomy and reviewed the clinical data and pathologic reports of 313 polyps from a university hospital. Two endoscopists each performed colonoscopy and polypectomy and assessed the CSM. The association between CSM surrounding colorectal polyps and histology was analyzed.

Results

The majority (91.3%) of CSM-positive polyps were neoplastic (sensitivity, 37.90%; specificity, 86.15%; p<0.001). In logistic regression, the neoplastic polyps were associated with positive CSM (adjusted odds ratio [OR], 3.51; 95% confidence interval [CI], 1.45 to 9.25; p=0.007), protruded polyps (adjusted OR, 4.85; 95% CI, 1.65 to 17.23; p=0.008), and neoplastic histology–associated pit pattern (pit III, IV, and V) (adjusted OR, 10.14; 95% CI, 4.85 to 22.12; p=0.000). Furthermore, advanced adenomas were associated with positive CSM (adjusted OR, 5.64; 95% CI, 1.77 to 20.28; p=0.005), protruded polyps (adjusted OR, 3.30; 95% CI, 1.15 to 9.74; p= 0.026), and ≥10 cm polyp size (adjusted OR, 18.56; 95% CI, 3.89 to 147.01; p=0.001).

Conclusions

Neoplastic and advanced polyps were associated with CSM-positive polyps. These findings suggest that CSM is a useful marker in differentiating neoplastic polyps and advanced polyps under conventional white colonoscopy.

Acromegaly and Colorectal Neoplasm: An Update

Acromegaly is a systemic disease caused by excessive inappropriate secretion of GH and IGF-I levels, resulting in many systemic complications, including cardiovascular, respiratory, metabolic diseases, and a possible increased risk of some neoplasias. Although many studies on acromegaly and cancer remain uncertain, most data indicate that colorectal cancer (CRC) incidence is increased in this population. The exact mechanism involved in the role of GH-IGF-I axis in CRC has not been fully explained, yet it is associated with local and circulating effects of GH and IGF-I on the colon, promoting angiogenesis, cell proliferation, risk of mutation, inhibition of tumor-suppressor genes and apoptosis, thus facilitating a tumor microenvironment. Nevertheless, population-based studies present controversial findings on CRC incidence and mortality. All worldwide guidelines and expert consensuses agree with the need for colonoscopic screening and surveillance in acromegaly, although there is no consensus regarding the best period to do this. This review aims to analyze the existing data on CRC and acromegaly, exploring its pathophysiology, epidemiological studies and their limitations, colonic polyp characteristics, overall cancer and CRC incidences and mortality, risk factors for colon cancer pathophysiology, and recommendation guideline aspects.

Melanosis coli: A factor not associated with histological progression of colorectal polyps

OBJECTIVE

In this study we aimed to investigate the association of melanosis coli (MC) and the colorectal polyp detection rate (PDR).

METHODS

In all, 1104 MC patients and 62 181 non-MC participants were enrolled. And 2208 controls were matched by participants' age and gender, and quality of bowel preparation using the propensity score matching (PSM) method. Additionally, 490 polyps in MC and 980 in controls matched by age and gender, and size and location of polyps were analyzed. The association of PDR and pathological features of polyps with MC were also analyzed.

RESULTS

MC patients showed a higher PDR (44.3% vs 39.3%, P = 0.006) and detection rate of low-grade adenoma (45.4% vs 36.7%, P = 0.002) but fewer large polyps (≥10 mm) (18.8% vs 26.9%, P = 0.001), fewer polyps in the left colon (33.5% vs 40.0%, P = 0.018), and a lower detection rate of advanced adenoma/adenocarcinoma (17.4% vs 24.3%, P = 0.003) than the matched controls. On multivariate logistic regression analysis, MC was independently associated with an increased PDR (odds ratio 1.184, 95% confidence interval 1.045-1.343, P = 0.008). Analysis targeting polyps showed that there were significant differences in age, gender, location, and pathology (P < 0.001) between polyps with and without MC. However, after adjusting for participants' age and gender, size and location of polyps, there was no difference between the two groups in pathology (P = 0.635).

CONCLUSION

MC is independently associated with increased colorectal PDR, but not with histological progression of polyps.

MSRF-Net: A Multi-Scale Residual Fusion Network for Biomedical Image Segmentation

Methods based on convolutional neural networks have improved the performance of biomedical image segmentation. However, most of these methods cannot efficiently segment objects of variable sizes and train on small and biased datasets, which are common for biomedical use cases. While methods exist that incorporate multi-scale fusion approaches to address the challenges arising with variable sizes, they usually use complex models that are more suitable for general semantic segmentation problems. In this paper, we propose a novel architecture called Multi-Scale Residual Fusion Network (MSRF-Net), which is specially designed for medical image segmentation. The proposed MSRF-Net is able to exchange multi-scale features of varying receptive fields using a Dual-Scale Dense Fusion (DSDF) block. Our DSDF block can exchange information rigorously across two different resolution scales, and our MSRF sub-network uses multiple DSDF blocks in sequence to perform multi-scale fusion. This allows the preservation of resolution, improved information flow and propagation of both high- and low-level features to obtain accurate segmentation maps. The proposed MSRF-Net allows to capture object variabilities and provides improved results on different biomedical datasets. Extensive experiments on MSRF-Net demonstrate that the proposed method outperforms the cutting edge medical image segmentation methods on four publicly available datasets. We achieve the Dice Coefficient (DSC) of 0.9217, 0.9420, and 0.9224, 0.8824 on Kvasir-SEG, CVC-ClinicDB, 2018 Data Science Bowl dataset, and ISIC-2018 skin lesion segmentation challenge dataset respectively. We further conducted generalizability tests that also achieved the highest DSC score with 0.7921 and 0.7575 on CVC-ClinicDB and Kvasir-SEG, respectively.

Timeliness of diagnosis and treatment: the challenge of childhood cancers

Cancer represents an important cause of disease-related death in children worldwide. Improved treatment and understanding of the ways in which cancer manifests has allowed for a greater prospect of survival in children of all ages. However, variation in childhood cancer experience exists based on factors at the individual, community and systems levels. Throughout the cancer care continuum these factors may influence the access and timeliness of care a child receives, leading to delays in diagnosis and treatment. The pejorative designation 'delay in diagnosis and treatment' is better characterised as lag time, representing an interval that is thought to influence survival and overall outcome. In recent decades, work has been done to expedite early childhood cancer diagnosis through the creation of screening and education-based programmes. Although systematic cancer screening in children poses risks and fails to achieve the goal of early diagnosis, a case has been made for risk-based surveillance that has been shown to improve outcome and reduce occurrence of advanced stage disease in targeted populations. The components of lag time are examined separately and individually. This review highlights the challenges of early diagnosis in childhood cancers and describes important contributors in the cancer care continuum.

Designing a Predictive Model for Colorectal Neoplasia Diagnosis Based on Clinical and Laboratory Findings in Colonoscopy Candidate Patients

BACKGROUND

Health authorities have expanded two strategies to diminish CRC-related influence: CR screening and improve diagnostic process in symptomatic patients. The aim of the current study is to design a predictive model to identify the most important risk factors that can efficiently predict patients who have high risk of colorectal neoplasia.

METHOD

A cross-sectional study was constructed to include all patients who had positive test for FIT or had one or more risk factors for colorectal cancer based on the guidelines of detecting high-risk groups for colorectal cancer in Iran. Multivariable binary logistic regression model was constructed for prediction of colorectal neoplasia. We used sensitivity, specificity, positive and negative predictive value, and positive and negative likelihood ratio to check the accuracy. The Hosmer-Lemeshow test, chi-square test, and p value were used to determine the precision of model.

RESULT

Following an AIC stepwise selection model, only nine potential variables, namely gender, watery diarrhea, IBD, abdominal pain, melena, body mass index, depression drug, anti-inflammatory drug, and age, were found to be a predictor of colorectal neoplasia. The best cut-point probability in the final model was 0.27 and results of sensitivity and specificity, based on maximizing these two criteria, were 66% and 62%, respectively.

CONCLUSION

Overall, our model prediction was comparable with other risk prediction models for colorectal cancer. It had a modest discriminatory power to distinguish an individual's neoplasia colorectal risk.

Barriers and facilitators of colorectal cancer screening in Asia

Purpose

One of the most common cancers in Asia is colorectal cancer (CRC). Early diagnosis and timely treatment are necessary for preventing complications and advanced stages of the disease. It is important to evaluate barriers and facilitators of screening in different countries. This systematic review aimed to identify the barriers and facilitators of CRC screening in Asia.

Methods

In this systematic review, for identifying barriers and facilitators of CRC screening, a comprehensive search was conducted in PubMed, Web of Science and Scopus in 12 December 2020. Combination keywords such as colorectal cancer, screening, sigmoidoscopy, colonoscopy, faecal occult blood test, barriers, facilitators and the names of each Asian country were used for searching. Full text original studies in English language were accepted in the review.

Results

In total, 36 articles were included in the review. Barriers and facilitators were evaluated. The most common reported barriers were lack of knowledge, fear of result, fear of procedure, fear of pain, lack of awareness, high cost and lack of gastrointestinal symptoms. The most frequent facilitators were having knowledge and awareness of CRC screening, perceived risk and severity, family history of cancer and physician recommendation.

Conclusion

For promoting success in CRC screening programmes, knowing what the barriers and facilitators are is necessary. Awareness and various personal, professional and social factors have been shown to be the major barriers toward CRC screening in most Asian countries.

Efficacy and Safety of TJP-008 Compared to 2 L PEG with Ascorbate in Colon Cleansing: A Randomized Phase 3 Trial

Background/Aims

Polyethylene glycol (PEG)-based bowel preparations are effective cleansing agents for colonoscopy. However, they require relatively large volumes to be used even with agents such as 2 L PEG with ascorbate (2LPEG). This phase 3, randomized, single-blinded, multicenter, parallel-group study compared the efficacy of 1 L PEG with high-dose ascorbate, TJP-008, to 2LPEG.

Methods

Patients undergoing colonoscopy were randomized (111) to receive TJP-008 as 1-day split dose (TJP-008-1) or 2-day split dose (TJP-008-2) regimen or to receive 2LPEG as a 2-day split dose regimen. Cleansing efficacy was evaluated using the Harefield Cleansing Scale. The primary endpoint was overall bowel cleansing success. Full analysis set (FAS) and per protocol set (PPS) analyses were performed.

Results

Of the 314 screened patients, efficacy was assessed in the following patient numbers (FAS/PPS) total (293/285), TJP-008-1 (98/94), TJP-008-2 (97/95), and 2LPEG (98/96). FAS revealed noninferiority between TJP-008 and 2LPEG with regard to overall success (TJP-008-2, 99.0%; TJP-008-1, 95.9%; 2LPEG, 94.9%; p=0.100 and p=0.733, respectively). PPS also showed noninferiority (p=0.721 and p=0.211, respectively). However, the PPS analyses showed a higher bowel cleansing score for TJP-008-2 for high-quality cleansing in the right colon (TJP-008-2 83.2% vs 2LPEG 62.5%; p=0.005).

Conclusions

TJP-008 is a new low-volume cleansing agent with a colon cleansing efficacy comparable to that of standard 2LPEG that exhibits significant safety and tolerability.

Recurrence of Colorectal Neoplastic Polyps After Incomplete Resection

BACKGROUND

Incomplete resection of neoplastic polyps is considered an important reason for the development of colorectal cancer. However, there are no data on the natural history of polyps that were incompletely removed.

OBJECTIVE

To examine the risk for metachronous neoplasia during surveillance colonoscopy after documented incomplete polyp resection.

DESIGN

Observational cohort study of patients who participated in the CARE (Complete Adenoma REsection) study (2009 to 2012).

SETTING

2 academic medical centers.

PATIENTS

Patients who had resection of a 5- to 20-mm neoplastic polyp, had a documented complete or incomplete resection, and had a surveillance examination.

MEASUREMENTS

Segment metachronous neoplasia, defined as the proportion of colon segments with at least 1 neoplastic polyp at first surveillance examination, was measured. Segment metachronous neoplasia was compared between segments with a prior incomplete polyp resection (incomplete segments) and those with a prior complete resection (complete segments), accounting for clustering of segments within patients.

RESULTS

Of 233 participants in the original study, 166 (71%) had at least 1 surveillance examination. Median time to surveillance was shorter after incomplete versus complete resection (median, 17 vs. 45 months). The risk for any metachronous neoplasia was greater in segments with incomplete versus complete resection (52% vs. 23%; risk difference [RD], 28% [95% CI, 9% to 47%]; P = 0.004). Incomplete segments also had a greater number of neoplastic polyps (mean, 0.8 vs. 0.3; RD, 0.50 [CI, 0.1 to 0.9]; P = 0.008) and greater risk for advanced neoplasia (18% vs. 3%; RD, 15% [CI, 1% to 29%]; P = 0.034). Incomplete resection was the strongest independent factor associated with metachronous neoplasia (odds ratio, 3.0 [CI, 1.12 to 8.17]).

LIMITATION

Potential patient selection bias due to incomplete follow-up.

CONCLUSION

This natural history study found a statistically significantly greater risk for future neoplasia and advanced neoplasia in colon segments after incomplete resection compared with segments with complete resection.

PRIMARY FUNDING SOURCE

None.

Volume of surgical interventions for benign colorectal tumors – an analysis of 3510 surgical and endoscopic resections in the single colorectal center in Poland

Introduction: Colorectal cancer is the most frequent neoplasm of the whole gastrointestinal track. Due to screening colonoscopy program, colorectal lesions are often diagnosed at early stage. The vast majority of them are possible to remove endoscopically. However, a substantial percentage of benign lesion in Western centers are still operated. The aim of this article was to determine the percentage of surgical resections due to benign adenomas in the reference center of endoscopic submucosal dissection (ESD) and colorectal surgery in Poland. Materials and Methods: Retrospective analysis of 3 510 patients operated from 2015 to 2019 in Center of Bowel Treatment in Brzeziny. Results: We have analyzed 3 510 endoscopic and surgical procedures performed in the colon: 601 ESDs; 1 002 endoscopic mucosal resections (EMRs); and 1,907 surgical resections. Out of 601 ESDs, 57 invaded the submucosa, of which 29 (4.8%) were non-therapeutic ESDs. In 5 patients, due to occurrence of post-ESD perforation, an additional surgical intervention was necessary. Out of the 1,002 EMRs, 22 cases (2.2%) were diagnosed with deeply infiltrating cancers, which required a surgery. The overall percentage of the need for surgery in the endoscopically treated patients (ESD + mucosectomy) was 3.5% (56/1 603). Among resection surgeries, 15 of them (0.8%) ended with the diagnosis of a benign lesion in the postoperative histopathological examination. Conclusions: Inclusion advanced endoscopic techniques such as ESD to routine clinical practice in colorectal centers gives clear benefits for the patients. Well defined and standardized process of qualifying for appropriate treatment allows to significantly reduce the percentage of abdominal approach surgery due to benign colorectal lesions.  

A sex-specific propensity-adjusted analysis of colonic adenoma detection rates in a screening cohort

The prevalence of colorectal adenoma and advanced adenoma (AA) differs between sexes. Also, the optimal age for the first screening colonoscopy is under debate. We, therefore, performed a sex-specific and age-adjusted comparison of adenoma, AA and advanced neoplasia (AN) rates in a real-world screening cohort. In total, 2824 asymptomatic participants between 45- and 60-years undergoing screening colonoscopy at a single-centre in Austria were evaluated. 46% were females and mean age was 53 ± 4 years. A propensity score for being female was calculated, and adenoma, AA and AN detection rates evaluated using uni- and multivariable logistic regression. Sensitivity analyses for three age groups (group 1: 45 to 49 years, n = 521, 41% females, mean age 47 ± 1 years; group 2: 50 to 54 years, n = 1164, 47% females, mean age 52 ± 1 years; group 3: 55 to 60 years, n = 1139, 46% females, mean age 57 ± 2 years) were performed. The prevalence of any adenoma was lower in females (17% vs. 30%; OR 0.46, 95% CI 0.38–0.55; p < 0.001) and remained so after propensity score adjustment for baseline characteristics and lifestyle factors (aOR 0.52, 95% CI 0.41–0.66; p < 0.001). The same trend was seen for AA with a significantly lower prevalence in females (3% vs. 7%; OR 0.38, 95% CI 0.26–0.55; p < 0.001) that persisted after propensity score adjustment (aOR 0.54, 95% CI 0.34–0.86; p = 0.01). Also, all age-group sensitivity analyses showed lower adenoma, AA and AN rates in females. Similar numbers needed to screen to detect an adenoma, an AA or AN were found in female age group 3 and male age group 1. Colorectal adenoma, AA and AN were consistently lower in females even after propensity score adjustment and in all age-adjusted sensitivity analyses. Our study may add to the discussion of the optimal age for initial screening colonoscopy which may differ between the sexes.