Clinical practice. Screening for colorectal cancer

Body mass index and the prevalence of high-risk colorectal adenomas in a population undergoing screening colonoscopy in Alberta, Canada

PURPOSE

There is limited evidence regarding body mass index (BMI) as an early marker of high-risk adenoma (HRA) at the time of screening colonoscopy. Because high-risk adenomas (HRA) can develop into colorectal cancer (CRC), BMI could serve as an important clinical predictor of future risk of CRC.

METHODS

We examined data from 1831 adults undergoing screening colonoscopy at the Forzani & MacPhail Colon Cancer Screening Center in Alberta, Canada. We fit multivariable logistic regression models to examine the association between BMI and HRA. Non-linear relationships for BMI on HRA were also evaluated using restricted cubic splines.

RESULTS

The mean BMI in patients with HRA was 28.2 kg/m2 compared to 27.4 kg/m2 in patients without adenomas (t test: p = 0.003). In the adjusted models, those with a BMI over 30 kg/m2 had 1.45 (95% CI 1.05-2.00) times the odds of HRA detected during colonoscopy compared to those with a BMI below 25 kg/m2. Examining BMI as continuous, the odds of HRA were 1.20 (95% CI 1.04-1.37) times higher for every 5 kg/m2 increase in BMI.

CONCLUSION

The findings of this study suggest that excess body mass is associated with higher risk of HRA among a screening population and may be useful an early marker of future disease.

Colorectal polyps in young adults: a retrospective review of colonoscopy data from Toowoomba and the Darling Downs

BACKGROUND

Polyps are the predominant precursors of colorectal cancer. In the past three decades, the incidence and mortality rates of colorectal cancer have been increasing in adults younger than 50 years.

AIMS

The aim of this clinical audit was to evaluate the prevalence, characteristics and clinical associations of polyps in adults aged 18-49 years presenting to an established private gastroenterology clinic in the Toowoomba Darling Downs region.

METHODS

The audit included data from 353 patient records held by the Toowoomba Gastroenterology Clinic. Data extracted from patient medical records through the Medical Director program software contained structured endoscopy/colonoscopy and histology reports of excised lesions of patients presenting to the clinic. The extract involved identifying all patients aged 18-49 years in the database from January 2019 to March 2022. Patients were screened based on audit inclusion and exclusion criteria. Patients were risk stratified for recommended surveillance intervals as per Australian Clinical Guidelines.

RESULTS

Of the sample population, 33.4% were identified with polyps and 22.4% were identified with neoplastic polyps (NPs). A total of 6.7% of 18- to 29-year-old patients were identified with intermediate risk for colorectal cancer (CRC) screening, and 19.8% and 19.3% of 30- to 39-year-old and 40- to 49-year-old patients identified with intermediate or high risk for CRC screening respectively. Increased age, greater size of polyps and surveillance of previous polyps were associated with increased NP prevalence.

CONCLUSIONS

Data from this audit supported the temporal trend of increasing prevalence of polyps in adults younger than 50 years. Patient cohorts aged 30-39 and 40-49 years may benefit from earlier first colonoscopies. Findings could be the impetus for future research in young adults presenting for colonoscopy.

Colorectal cancer screening; colonoscopy and biopsy results in people undergoing colonoscopy due to positive fecal occult blood test

Objectives

Screening programs are important for the early detection of colorectal cancer, which is one of the causes of high morbidity and mortality. In this study, we investigated the colonoscopy results, the incidence of adenoma and cancer, and the relationship between test results and cancer in individuals with a positive fecal occult blood test for colorectal cancer screening.

Material and Methods

Within the scope of the colorectal cancer screening program, colonoscopy was requested for individuals aged 50-70 years who applied to our outpatient clinic with a positive fecal occult blood test. The results were collected and analyzed.

Results

The results of the colonoscopy could be obtained in only 237 (56.43%) of the 420 patients who were referred for a colonoscopy because of a positive fecal occult blood test. Colonoscopy results were normal in 15 (6.33%), benign anal disease in 64 (27%), benign colonic disease in 12 (5.06%) and polyp + adenocarcinoma in 146 (61.61%). Pathology results were benign polyp in 37 (15.61%), adenomatous polyp in 86 (36.29%) and adenocarcinoma in 23 (9.71%). Quantitative test results were higher in the adenomatous polyp + adenocarcinoma group and statistically significant (p= 0.03).

Conclusion

Individuals with positive fecal occult blood tests, especially those with high quantitative test results, should be encouraged to have a colonoscopy, and they should be warned about the high probability of adenomatous polyps and colorectal cancer.

Steadfast Toll Like Receptor 4 (TLR4) 5-Hydroxymethylcytosine Levels in Cell-Free DNA: A Promising Consistency Marker for Colorectal Cancer Patients

Cell-free DNA (cfDNA) from patient blood is emerging as a noninvasive diagnostic avenue for various cancers. We aimed to identify reliable biomarkers in cfDNA by investigating genes exhibiting significant differences between colorectal cancer and control samples. Our objective was to identify genes that showed a positive difference between cancer and control samples. To achieve this, we conducted an in silico analysis to identify genes that exhibit no significant variation in methylation between genomic DNA (gDNA) and cfDNA. We collected experimental data from publicly available repositories, which included 5-hydroxymethylcytosine (5hmC) profiles of gDNA and cfDNA samples from both cancer patients and healthy individuals. By comparing and overlapping these two groups, we identified 187 genes of interest, of which 53 genes had a positive difference among colon cancer patients and healthy individuals. Next, we performed an ANOVA test on these genes, resulting in the identification of 12 genes that showed statistically significant higher levels of 5hmC in cfDNA and gDNA from cancer patients compared to healthy individuals. Additionally, we compared the 5hmC status of these genes between cfDNA and gDNA from cancer patients. Interestingly, we found that the 5hmC of the toll like receptor 4 (TLR4) gene was not statistically different between cfDNA and gDNA from cancer patients, indicating consistency between cfDNA and gDNA. These findings have important implications, not only for experimental validation but also for the development of more sensitive and robust noninvasive methods to improve diagnostic, prognostic, and treatment options for colon cancer.

A Scoring Method to Prioritize Fecal Occult Blood Testing as a First Step in Colorectal Cancer Screening in Resource-Limited Settings

This study aims to develop a scoring method that can be used by primary care physicians from remote areas or resource-limited settings to estimate the need for fecal occult blood testing (FOBT) as a first step in colorectal cancer screening. This method relies on several modifiable risk factors that can influence a positive FOBT, an indication of the presence of colorectal polyps, or even colorectal cancer. The scoring method considers, besides the age and gender of the patient, the body mass index (BMI), smoking status, and the diagnoses of diabetes mellitus (type 2 diabetes), dyslipidemia, and hypertension. It does not need any paraclinical exams, which is an advantage when access or material resources are limited. The retrospective study was spread over forty-three months, respectively, from October 2019 to April 2023, and included 112 patients. The score that we designed is a numerical value between 0 and 7. The values between 0 and 3 represent a smaller risk of a positive FOBT (9.68%), values 4 and 5 represent a medium risk (14.75%), while values 6 and 7 represent a greater risk (40%). Using this score, a physician can determine if a patient has a greater risk and recommend it to prioritize taking a FOB test.

Screening of malignant neoplasms: the state of the problem in Russia and the world

A number of objective and subjective reasons, such as aging of the population, environmental, economic and other factors, determine the trend of increasing incidence of malignant neoplasms worldwide. According to GLOBOCAN 2020 forecasts, in the coming years, prostate, lung and bronchial cancer, colorectal cancer will account for almost half (48%) of all cases of the disease in men, of which 27% are prostate cancer. In women, breast cancer, lung cancer and colorectal cancer will account for about 51% of all new diagnoses, while breast cancer alone will account for about 30%. In 2021, the Ministry of Health of the Russian Federation approved the Procedure for preventive examinations and medical examinations, within the framework of which screening measures for early detection of oncological diseases are carried out, the procedure for dispensary observation of certain groups of the adult population by specialist doctors is approved, the duration, frequency of dispensary observation, the scope of preventive, diagnostic, therapeutic and rehabilitation measures are determined. The aim of the review: to present epidemiological data on the most common forms of cancer in Russia and the world; current recommendations on the organization of screening and its informative value; primary prevention measures.

Importance of the neutrophil-lymphocyte ratio and systemic immune-inflammation index in predicting colorectal pathologies in fecal occult blood-positive patients

BACKGROUND

The fecal occult blood (FOB) test is one of the primary screening methods for colorectal cancer (CRC). In this study, we aimed to investigate the effect of the neutrophil/lymphocyte ratio (NLR) and systemic immune-inflammation index (SII) in predicting CRC and other colorectal pathologies in patients with a positive FOB test.

METHODS

This retrospective study included patients with a positive FOB test who underwent colonoscopy for the investigation of the etiology. The optimal cutoff levels of NLR and SII for predicting colorectal pathologies were determined using the receiver operating characteristic analysis.

RESULTS

Of the 157 FOB+ patients, 35% were male and 65% were female, with a median age of 59 years. There were 96 patients in Group 1 and 61 patients in Group 2. The mean age of the patients in Group 2 was significantly higher (p < 0.001). The rate of male patients was significantly higher in Group 2. NLR and SII were significantly higher in Group 2 than in Group 1 (p < 0.001). The area under the curve values of NLR and SII in predicting colorectal pathologies in FOB+ patients were 0.817 and 0.825, respectively. At the cutoff values of 0.689 and 0.795, NLR and SII had a sensitivity of 60.66% and 95.83%, respectively, and a specificity of 95.83% and 100%, respectively.

CONCLUSION

Neutrophil/lymphocyte ratio and SII can be used as important biomarkers in the early diagnosis of CRC and other colorectal lesions in patients with a positive FOB test.

Magnetic Nanoparticle-Based Electrochemical Sensing Platform Using Ferrocene-Labelled Peptide Nucleic Acid for the Early Diagnosis of Colorectal Cancer

Diagnostic biomarkers based on epigenetic changes such as DNA methylation are promising tools for early cancer diagnosis. However, there are significant difficulties in directly and specifically detecting methylated DNA regions. Here, we report an electrochemical sensing system based on magnetic nanoparticles that enable a quantitative and selective analysis of the methylated septin9 (mSEPT9) gene, which is considered a diagnostic marker in early stage colorectal cancer (CRC). Methylation levels of SEPT9 in CRC samples were successfully followed by the selective recognition ability of a related peptide nucleic acid (PNA) after hybridization with DNA fragments in human patients’ serums and plasma (n = 10). Moreover, this system was also adapted into a point-of-care (POC) device for a one-step detection platform. The detection of mSEPT9 demonstrated a limit of detection (LOD) value of 0.37% and interference-free measurement in the presence of branched-chain amino acid transaminase 1 (BCAT1) and SRY box transcription factor 21 antisense divergent transcript 1 (SOX21-AS1). The currently proposed functional platform has substantial prospects in translational applications of early CRC detection.

Comparison Between Same-Day and Split-Dose Preparations with Sodium Picosulfate/Magnesium Citrate: A Randomized Noninferiority Study

BACKGROUND

Sodium picosulfate/magnesium citrate (SPMC) is a small-volume bowel cleansing agent with similar efficacy to and better tolerability than polyethylene glycol. However, we found no data on which SPMC preparation (same-day vs. split-dose) provides better bowel cleansing efficacy for afternoon colonoscopy.

AIMS

To compare bowel cleansing efficacy of different timing of the regimen.

METHODS

This randomized, single-center, endoscopist-blinded, noninferior study compared same-day and split-dose SPMC preparations for afternoon colonoscopy in 101 and 96 patients, respectively. We also included a prospective observation group of 100 patients receiving morning colonoscopy to compare bowel preparation between morning and afternoon colonoscopies. Bowel cleansing efficacy was then evaluated by the Aronchick Scale, Ottawa Bowel Preparation Scale (OBPS), Boston Bowel Preparation Scale (BBPS), and the Bubble Scale.

RESULTS

Same-day and split-dose preparations were similar in efficacy in all four scales. In the Aronchick Scale, the success rate (excellent and good cleanliness) was higher in same-day preparation than in split-dose preparation (100% vs. 92.8%). The same-day preparation also obtained a better OBPS score (1.4 vs. 2.1), but BBPS showed no difference between such groups (7.7 vs. 7.4).

CONCLUSION

Same-day preparation with SPMC is not inferior to split-dose preparation for afternoon colonoscopy.

Diagnostic Potential of Exosomal microRNAs in Colorectal Cancer

Background: Despite the significance of colonoscopy for early diagnosis of colorectal adenocarcinoma (CRC), population-wide screening remains challenging, mainly because of low acceptance rates. Herein, exosomal (exo-miR) and free circulating microRNA (c-miR) may be used as liquid biopsies in CRC to identify individuals at risk. Direct comparison of both compartments has shown inconclusive results, which is why we directly compared a panel of 10 microRNAs in this entity. Methods: Exo-miR and c-miR levels were measured using real-time quantitative PCR after isolation from serum specimens in a cohort of 69 patients. Furthermore, results were compared to established tumor markers CEA and CA 19-9. Results: Direct comparison of exo- and c-miR biopsy results showed significantly higher microRNA levels in the exosomal compartment (p < 0.001). Exo-Let7, exo-miR-16 and exo-miR-23 significantly differed between CRC and healthy controls (all p < 0.05), while no c-miR showed this potential. Sensitivity and specificity can be further enhanced using combinations of multiple exosomal miRNAs. Conclusions: Exosomal microRNA should be considered as a promising biomarker in CRC for future studies. Nonetheless, results may show interference with common comorbidities, which must be taken into account in future studies.

Colonoscopy polyp detection and classification: Dataset creation and comparative evaluations

Colorectal cancer (CRC) is one of the most common types of cancer with a high mortality rate. Colonoscopy is the preferred procedure for CRC screening and has proven to be effective in reducing CRC mortality. Thus, a reliable computer-aided polyp detection and classification system can significantly increase the effectiveness of colonoscopy. In this paper, we create an endoscopic dataset collected from various sources and annotate the ground truth of polyp location and classification results with the help of experienced gastroenterologists. The dataset can serve as a benchmark platform to train and evaluate the machine learning models for polyp classification. We have also compared the performance of eight state-of-the-art deep learning-based object detection models. The results demonstrate that deep CNN models are promising in CRC screening. This work can serve as a baseline for future research in polyp detection and classification.

Colorectal Cancer after Kidney Transplantation: A Screening Colonoscopy Case-Control Study

The incidence of colorectal cancer in kidney transplant recipients has been previously reported with conflicting results. In this study, we investigated if the incidence of colorectal advanced neoplasms in kidney transplant recipients, evaluated with screening colonoscopy, was higher than in healthy individuals. One-hundred sixty kidney transplant recipients undergoing screening colonoscopy were compared with 594 age- and sex-matched healthy individuals. Advanced colorectal neoplasia was found in 22 patients (13.7%), including four patients (2.5%) with colorectal cancer. Compared with the healthy population, kidney transplant recipients did not have an increased risk of developing a colorectal cancer (OR 0.69; 95% CI 0.236–2.063, p = 0.688) although it developed at a younger age. In contrast, kidney transplant recipients had a higher risk of developing an advanced adenoma compared with the control group (OR 1.65; 95% CI 0.930–2.981, p = 0.04). In conclusion, kidney transplant recipients did not have an increased incidence of colorectal cancer compared with healthy population. However, transplant patients displayed a higher incidence of colorectal adenomas, suggesting that screening colonoscopy in kidney transplant recipients should be expanded to include even younger recipients (<50 years old).

A clinical nomogram incorporating salivary Desulfovibrio desulfuricans level and oral hygiene index for predicting colorectal cancer

Background

Emerging evidence demonstrates that the salivary microbiome could serve as a biomarker for various diseases. To date, the oral microbiome’s role in the diagnosis of colorectal cancer (CRC) has not been fully elucidated. We aimed to illustrate the salivary microbiome’s role in diagnosing and predicting the risk of CRC.

Methods

We collected preoperational saliva from 237 patients [95 healthy controls (HCs) and 142 CRC patients] who underwent surgical resections or colorectal endoscopy in Renji Hospital from January 2018 to January 2020. Clinical demographics, comorbidities, and oral health conditions were obtained from medical records or questionnaires. Salivary microbial biomarkers were detected using quantitative polymerase chain reaction (qPCR) after DNA extraction. Multivariate logistic regression analysis was employed to analyze the risk factors for CRC. A predictive model for the risk of developing CRC was constructed based on logistic regression analysis. Predictive accuracy was internally validated by bootstrap resampling. A clinical nomogram was constructed to visualize the predictive model.

Results

Logistic regression analysis demonstrated that the risk factors associated with CRC included age at diagnosis, male sex, poor oral hygiene, and relative salivary Desulfovibrio desulfuricans abundance. The predictive model had good discriminative (0.866) and calibration abilities (0.834) after bias correction.

Conclusions

The model based on age, sex, oral hygiene index (OHI), and the salivary Desulfovibrio desulfuricans level, which is visualized by a clinical nomogram, can predict the risk of CRC. Developing good oral hygiene habits might reduce the risk of CRC.

Usefulness of mean number of adenomas per positive screenee for identifying meticulous endoscopists among those who achieve acceptable adenoma detection rates

BACKGROUND

Adenoma detection rate (ADR) is a quality indicator for colonoscopy. However, many missed adenomas have subsequently been identified after colonoscopies performed by endoscopists with ADR ≥ 25 %. Adenomas per positive participant (APP; mean number of adenomas detected by an endoscopist among screenees with positive findings) correlates well inversely with adenoma miss rate. This study aimed to evaluate whether APP added additional information on the detection rate for advanced adenomas (AADR) and proximal adenomas (pADR) and among endoscopists with acceptable ADRs (≥ 25 %).

METHODS

A total of 47 endoscopists performed 7339 screening colonoscopies that were retrospectively reviewed. Using a cutoff APP value of 2.0, endoscopist performance was classified as high or low APP. Endoscopist ADRs were also classified as acceptable (25 % - 29 %), high standard (30 % - 39 %) and aspirational (≥ 40 %). Generalized linear models were used to assess the relationship between AADR or pADR, and ADR and APP, after adjusting for potential confounders.

RESULTS

After adjusting for endoscopist performance and patient characteristics, endoscopists with high APP had a significant 2.1 percentage point increase in AADR (95 %CI 0.3 to 3.9; P = 0.02) and a 2.1 percentage point increase in pADR (95 %CI - 0.8 to 5.1; P = 0.15) compared to endoscopists with low APP. In total, 11 (24 %), 18 (38 %), and 18 (38 %) endoscopists were classified as having acceptable, high standard, and aspirational ADRs, respectively. APP values higher than the cutoff were found in 18 %, 44 %, and 72 % of endoscopists with acceptable, high standard, and aspirational ADRs, respectively (P = 0.02).

CONCLUSION

APP is helpful for identifying more meticulous endoscopists who can detect a greater number of advanced adenomas. Endoscopists who achieved an only acceptable ADR had the lowest APP.

Colonoscopy and polypectomy: beside age, size of polyps main factor for long-term risk of colorectal cancer in a screening population

PURPOSE

Despite national and international guideline recommendations, few studies have been conducted to estimate the impact of colonoscopy screening on long-term colorectal cancer incidence. Aim of this study was to determine the long-term impact of a full colonoscopy with polypectomy on colorectal cancer incidence in a large screening population.

METHODS

In this prospective observational cohort study, a total of 10,947 colonoscopy screening participants from within the scope of the Munich Cancer Registry were consecutively recruited from participating gastroenterology practices and their subsequent colorectal cancer incidence assessed. Predictive factors associated with colorectal cancer were also evaluated in univariate and multivariate analyses.

RESULTS

After a median follow-up of 14.24 years (95% CI [14.21-14.25]), 93 colorectal cancer cases were observed. This is equivalent to a truncated age-standardized rate of 69.0 (95% CI [43.3-94.7]) for male and 43.4 (95% CI [29.4-57.5]) for female participants (≥ 50 years at colonoscopy). The ratio of this observed to the expected rate from cancer registry data showed a 67% decrease in colorectal cancer incidence in the male and 65% in the female participants (p < 0.0001). In multivariate analysis of screening patients, age at screening (p < 0.0001) was the main predictive factor for colorectal cancer. In the subgroup with positive polyp findings, age (p < 0.0001) and the polyp size (p = 0.0002) were associated with colorectal cancer.

CONCLUSION

These results underline the significance of a full colonoscopy screening combined with polypectomy in reducing the total disease burden of colorectal cancer.

Effect of dynamic position changes on adenoma detection rate during colonoscope withdrawal: systematic review and meta-analysis

Background and study aims  The adenoma detection rate (ADR) is an important quality metric of colonoscopy. Higher ADR correlates with lower incidence of interval colorectal cancer. ADR is variable between endoscopists and depends upon the withdrawal technique amongst other factors. Dynamic position change (lateral rotation of patients with a view to keep the portion of the colon being inspected at a higher level) helps with luminal distension during the withdrawal phase. However, impact of this on ADR is not known in a pooled sample. We performed a systematic review and meta-analysis to study the impact of dynamic position changes during withdrawal phase of colonoscopy on ADR Methods  A comprehensive search of MEDLINE, EMBASE, Google Scholar, and the Cochrane Database was conducted from each database's inception to search for studies comparing dynamic position changes during colonoscope withdrawal with static left lateral position (control). The primary outcome of interest was ADR. Other studied outcomes were polyp detection rate (PDR) and withdrawal time. Outcomes were reported as pooled odds ratio (OR) with 95 % confidence intervals (CI) with statistical significance ( P  < 0.05). RevMan 5.3 software was used for statistical analysis. Results  Six studies were included in our analysis with 2860 patients. Of these, dynamic position change was implemented in 1177 patients while 1183 patients served as the controls. ADR was significantly higher in the dynamic position change group with pooled OR 1.36 (95 % CI, 1.15-1.61; P  < 0.01). There was low heterogeneity in inclusion studies (I ²  = 0 %). PDR was numerically higher in position change group (53.4 % vs 49.6 %) but not statistically significant ( P  = 0.16). Mean withdrawal time did not significantly change with dynamic position change (12.43 min vs 11.46 min, P  = 0.27). Conclusion  Position change during the withdrawal phase of colonoscopy can increase the ADR compared to static left lateral position. This is an easy and practical technique that can be implemented to improve ADR.

Efficacy of repeat forward-view examination of the right-sided colon during colonoscopy: A prospective randomized controlled trial

BACKGROUND AND AIM

Generally, colonoscopy is less effective for detecting colorectal adenomas in the right-sided colon compared with the distal colon. Repeat forward-view (RF) examination of the right-sided colon has been suggested to increase the adenoma detection rate (ADR). However, studies investigating the efficacy of RF examination are lacking. Thus, the aim of this study was to determine whether RF examination in the right-sided colon enhances right-sided ADR.

METHODS

We performed a prospective, randomized controlled trial, including asymptomatic subjects who underwent screening colonoscopy. Subjects were randomized to the RF group, in which the right-sided colon was examined twice in the forward view, or to the standard forward-view (SF) group, in which the right-sided colon was examined once in the forward view. The primary outcome was the right-sided ADR on RF examination of the right-sided colon.

RESULTS

A total of 640 subjects completed the study protocol (RF group, n = 320; SF group, n = 320). The right-sided ADR in the RF group was significantly higher than that in the SF group (17.5% vs 11.9%, respectively; P = 0.044). In the RF group, an additional 31 adenomas were found, resulting in an increased detection rate of adenomas of 38.3% compared with the first forward view. The ADR of the whole colon was similar between the groups.

CONCLUSIONS

In our prospective randomized controlled trial, RF examination of the right-sided colon, which can be easily performed in clinical practice, was associated with an increased rate of detection of right-sided ADR.

Incidence and risk factors of colonoscopic post-polypectomy bleeding and perforation in patients with end-stage renal disease

BACKGROUND AND AIMS

Colonoscopic polypectomy in end-stage renal disease (ESRD) patients are at risks of post-polypectomy bleeding and perforation, but evidences are limited. This study aimed to determine the incident polypectomy complications among ESRD patients.

METHODS

In the nationwide ESRD cohort, a propensity score matched case-control study design was conducted to assess risk associated with post-polypectomy bleeding and perforation using the Taiwanese National Health Insurance Research Database from 1997 to 2013 for adults aged 40 years and older; 7011 ESRD and 19 118 non-ESRD patients met the study criteria. A total of 5302 patients in each group were matched for further analyses. The primary endpoint was post-polypectomy bleeding or bowel perforation in 30 days. The secondary endpoint was mortality and length of hospital stay for the bleeding complications requiring hospitalization.

RESULTS

Overall incidences of post-polypectomy bleeding or perforation in patients with ESRD was higher than the non-ESRD group (5.83% vs 1.78%, P < 0.0001) in the matched cohort. High risk of adverse outcomes was associated with ESRD (adjusted odds ratio [aOR], 2.38, 95% confidence interval [CI], 1.85-3.05), female patient (aOR, 1.7, 95% CI, 1.37-2.11), history of acute myocardial infarction (aOR, 1.91, 95% CI, 1.1-3.32), liver disease (aOR, 1.79, 95% CI, 1.37-2.34), diabetes (aOR, 1.45, 95% CI, 1.16-1.82), cancer (aOR, 1.4, 95% CI, 1.09-1.81), inpatient setting (aOR, 13.19, 95% CI, 9.73-17.88), and prior use of clopidogrel (aOR, 1.61, 95% CI, 1.03-2.52) and warfarin (aOR, 2.03, 95% CI, 1.21-3.41).

CONCLUSIONS

End-stage renal disease was associated with approximately twofold higher risk of colonoscopic post-polypectomy bleeding or perforation and should be cautiously performed in this special population cohort.

Combined serum miR-29c and miR-149 expression analysis as diagnostic genetic markers for colorectal cancer

Circulating miRNAs gathered much interest in cancer research as noninvasive biomarkers. The aim of this study was to analyze the expression of miR-29c and miR-149 among colorectal cancer (CRC) patients and to explore their diagnostic and prognostic potentials in relation to the clinical and pathological features. The expression levels of miR-29c and miR-149 were evaluated in the sera of 80 CRC patients, 80 colorectal adenoma (CRA) patients, and 80 healthy controls using quantitative real time polymerase chain reaction (PCR). Carcinoembryonic antigen serum levels were assayed using enzyme-linked immunosorbent assay. miR-29c and miR-149 were significantly downregulated among CRC patients compared with CRA and controls (miR-29c, 0.54 ± 0.19 vs. 0.86 ± 0.12, 0.99 ± 0.07, P < 0.001, respectively; miR-149, 0.46 ± 0.19 vs. 0.74 ± 0.012, 1.0 ± 0.22, P < 0.001, respectively). miR-29c and miR-149 significantly associated with advanced stages of CRC, tumor size, and lymphatic metastasis. By using receiver operating characteristic curve analysis, combined miR-29c and miR-149 revealed the highest diagnostic potential for CRA (area under the curve [AUC] = 0.967) from healthy controls as well as the diagnosis of CRC (AUC = 0.98) from CRA. Moreover, combined miRNAs revealed high diagnostic potential for the earlier stages of CRC compared with advanced stages (AUC = 0.96). In conclusion, combined serum miR-29c and miR-149 expression analysis established novel noninvasive biomarker for early CRC diagnosis.

Volatile organic compounds analysis as a potential novel screening tool for colorectal cancer: A systematic review and meta-analysis

The purpose of this meta-analysis was to assess the usefulness of volatile organic compounds (VOC) as a potential novel biomarker for colorectal cancer (CRC).We systematically searched PubMed, Embase, Web of Science, and Cochrane Library databases for observational studies (published before November 25th, 2019; no language restrictions) comparing the VOC analysis between patients with CRC and healthy controls. We evaluated the pooled sensitivity, specificity, diagnostic odds ratio, positive and negative likelihood ratio, as well as summary receiver operating characteristic curve and area under the curve.We identified a total of 10 observational studies that included 381 patients with CRC and 436 healthy controls. Bivariate analysis yielded a pooled sensitivity of 0.82 (95% confidence interval [CI] = 0.77-0.86), specificity of 0.79 (95% CI = 0.71-0.85), positive likelihood ratio of 3.8 (95% CI = 2.8-5.3), and negative likelihood ratio of 0.23 (95% CI = 0.17-0.30). The area under the curve was 0.87 (95% CI = 0.84-0.90). The pooled diagnostic odds ratio was 17 (95% CI = 10-28). Sensitivity analysis indicated that the pooled results were stabilized. The Deeks' funnel plot asymmetry test (P = .41) suggested no potential publication bias.Our pooled data confirmed the associations between VOC analysis and CRC, highlighting the usefulness of VOC analysis as a potential novel screening tool for CRC. However, standardization of VOC collection and analysis methods for CRC screening is required in future research.

A Dodecapeptide Selected by Phage Display as a Potential Theranostic Probe for Colon Cancers

Aim

Colon cancer is one of the leading causes of cancer-related mortality. However, specific biomarkers for its diagnosis or treatment are not established well.

Methods

We developed a colon-cancer specific peptide probe using phage display libraries. We validated the specificity of this probe to colon cancer cells with immunohistochemical staining and FACS analysis using one normal cell and five colon cancer cell lines.

Results

This peptide probe maintained binding affinity even after serum incubation. For therapeutic applications, this peptide probe was conjugated to hematoporphyrin, a photosensitizer, which showed a significantly enhanced cellular uptake and high photodynamic effect to kill tumor cells. As another application, we made a nanoparticle modified from the peptide probe. It efficiently delivered SN-38, an anticancer drug, into tumor cells, and its tumor-targeting ability was observed in vivo after intravenous injection to the same xenograft model.

Conclusion

The noble dodecapeptide probe can be a promising candidate for both colon tumor diagnosis and targeted drug delivery.

Effect of dynamic position changes during colonoscope withdrawal: a meta-analysis of randomized controlled trials

BACKGROUND

Colonoscopies are considered to be the primary screening test and gold standard test for colorectal cancer. Position changes during colonoscope withdrawal are believed to be associated with an increased adenoma detection rate (ADR) and polyp detection rate (PDR). However, previous results conflicted, and this study aimed to elucidate the effectiveness of dynamic position changes during colonoscope withdrawal.

METHODS

The relevant publications were identified by searching the medical databases. The primary outcomes were the ADR and PDR, which were pooled and analyzed. The secondary outcome was the withdrawal time. The studies that supplied the ADR and PDR for different segments of the colon were separated into subgroup analyses.

RESULTS

Five randomized controlled trials were eligible for analysis. The total ADR was higher with dynamic position changes than with a static position (odds ratio, [OR] 1.34; 95% confidence interval [CI] 1.13-1.59; p < 0.001), with low evidence of between-study heterogeneity (I₂ = 0%). Although the total PDR was slightly higher with dynamic position changes than with a static position (OR 1.23; 95% CI 0.88-1.73), there difference was not statistically significant (p = 0.22). The withdrawal time was only increased by 0.47 min (95% CI - 0.11 to 1.06) with dynamic position changes, without statistical significance (p = 0.11). The subgroup analysis showed that the ADR and PDR for the transverse colon were higher with dynamic position changes, with pooled estimates of ADR (OR 1.72; 95% CI 1.02-2.88; p = 0.04) and PDR (OR 1.79; 95% CI 1.08-2.96; p = 0.02).

CONCLUSION

Dynamic position changes during colonoscope withdrawal increased the total ADR; however, no obvious increase was found in the total PDR. The withdrawal time was not significantly prolonged with dynamic position changes. Subgroup analysis showed that the ADR and PDR in the transverse colon were obviously improved with dynamic position changes.

Cap-Assisted Chromoendoscopy Using a Mounted Cap Versus Standard Colonoscopy for Adenoma Detection

OBJECTIVES

Some neoplastic lesions remain undetected on colonoscopy. To date, no studies have investigated whether combining cap-assisted colonoscopy with chromoendoscopy increases the adenoma detection rate (ADR). This study aimed to compare cap-assisted chromoendoscopy (CAP/CHROMO) with standard colonoscopy (SC) with respect to their efficacy in detecting adenomas.

METHODS

This prospective, multicenter, randomized controlled trial included asymptomatic subjects aged 45-75 years who underwent colonoscopy for the first time at 14 university hospitals. Subjects were randomized to either the CAP/CHROMO group (with 0.09% indigo carmine spraying using a cap-mounted catheter at the tip of the colonoscope) or the SC group. All polyps were resected, but only histologically confirmed neoplastic lesions were considered for analysis. The primary outcome was ADR, defined as the proportion of subjects with at least 1 adenoma.

RESULTS

A total of 1,905 subjects were randomized to the CAP/CHROMO (n = 948) or SC (n = 957) group at 14 centers. Subjects' demographic characteristics were similar between both groups. The CAP/CHROMO group had significantly higher ADR than the SC group (54.4% vs 44.9%, P < 0.001). Significantly, more subjects with at least 1 proximal colon adenoma were identified by CAP/CHROMO (38.6%) than by SC (31.2%) (P = 0.001). The proximal serrated polyp detection rate by CAP/CHROMO was significantly higher in the female subgroup vs SC. However, advanced ADR was not different between the CAP/CHROMO and SC groups (9.3% vs 7.6%, P = 0.180).

DISCUSSION

CAP/CHROMO markedly improved the ADR and enhanced the detection of proximal adenoma. CAP/CHROMO is feasible for routine application and will allow for a more effective surveillance program.

Hypoxia Induces Growth Differentiation Factor 15 to Promote the Metastasis of Colorectal Cancer via PERK-eIF2α Signaling

Hypoxia plays an essential role in orchestrating Epithelial-mesenchymal transition and promoting metastasis of colorectal cancer. However, the underlying mechanisms are still not well elucidated. Here, we present that hypoxic exposure causes endoplasmic reticulum stress and activates the unfolded protein response pathways, which drives GDF15 expression in colorectal cancer cells. Mechanistically, upregulated CHOP led by activated PERK-eIF2α signaling promotes GDF15 transcription via directly binding to its promoter. Further study implicates that hypoxia-induced GDF15 is required for the EMT and invasion of colorectal cancer cells; enforced expression of GDF15 promotes the mitochondrial oxidation of fatty acids in colorectal cancer cells. Moreover, the abrogation of GDF15 results in smaller xenograft tumors in size and impaired metastasis. GDF15 is expressed much more in tumor tissues of CRC patients and displays positive correlations with CHOP and HIF1α in mRNA levels. Our study demonstrates a novel molecular mechanism underlying hypoxia-promoted metastasis of CRC and provides PERK signaling-regulated GDF15 as a new and promising therapeutic target for clinical treatment and drug discovery.

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.

Current Update of Laboratory Molecular Diagnostics Advancement in Management of Colorectal Cancer (CRC)

Colorectal cancer (CRC) continues to be one of the most common cancers globally. The incidence has increased in developing countries in the past few decades, this could be partly attributed to aging populations and unhealthy lifestyles. While the treatment of CRC has seen significant improvement since the advent of target-specific therapies and personalized medicine, CRC is oftentimes detected at late or advanced stages, thereby reducing the efficacy of treatment. Hence, screening for early detection is still the key to combat CRC and to increase overall survival (OS). Considering that the field of medical diagnostics is moving towards molecular diagnostics, CRC can now be effectively screened and diagnosed with high accuracy and sensitivity. Depending on the tumor genotype and genetic profile of the individual, personalized treatments including tyrosine kinase inhibitor therapy and immunotherapy can be administered. Notably, there can be no one single treatment that is effective for all CRC patients due to the variation in tumor genetics, which highlights the importance of molecular diagnostics. This review provides insights on therapeutic modalities, molecular biomarkers, advancement of diagnostic technologies, and current challenges in managing CRC.

Stool-Based miR-92a and miR-144* as Noninvasive Biomarkers for Colorectal Cancer Screening

OBJECTIVES

Current noninvasive screening tests for colorectal cancer (CRC) have insufficient sensitivity. MicroRNA (miRNA) levels in stool have potential as markers for noninvasive screening of CRC. We evaluated the diagnostic value of stool miRNA levels and determined the optimal miRNA subtypes for detecting CRC.

METHODS

Stool samples were collected from 29 patients with CRC and 29 healthy controls. The stool levels of miR-21, miR-92a, miR-200c, miR-144*, miR-135a, miR-135b, miR-106a, and miR-17-3p were determined by real-time quantitative reverse transcription polymerase chain reaction. The sensitivity and specificity of the miRNAs for CRC were determined by receiver operating characteristics analysis.

RESULTS

Among the eight tested miRNAs, the mean stool levels of miR-21, miR-92a, miR-144*, and miR-17-3p differed significantly between the CRC group and the control group (p =0.014, 0.001, <0.001, and 0.008, respectively). The sensitivities and specificities of miR-21, miR-92, miR-144*, and miR-17-3p were 79.3 and 48.3%, 89.7 and 51.7%, 78.6 and 66.7%, and 67.9 and 70.8%, respectively. In a multivariate analysis, miR-92a and miR-144* were significantly associated with the presence of CRC (p = 0.03 and 0.011, respectively).

CONCLUSIONS

The stool levels of miR-92a and miR-144* showed good sensitivity and fair specificity for detection of CRC, and thus may be useful as noninvasive biomarkers for this disease.

Gender differences in health-related quality of life among patients with colorectal cancer

Background

Evidence has shown that colorectal cancer (CRC) survivors, especially women have a lower health-related quality of life (HRQOL). This study aimed to assess the QOL of CRC survivors as well as gender-related differences in the QOL of CRC patients in Northwest of Iran.

Methods

This cross-sectional study was conducted in East Azarbijaban. All patients aged ≥18 years, and diagnosed with CRC regardless of its stage and plans for treatment, and also referred to teaching hospitals within a two years' time frame of 2014-2016, were included in this study. The Persian version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) was completed for each patient by two trained interviewers. Student t-test and χ² test were used to analyze Gender differences among patients, clinical-epidemiological characteristics, as well as the scores of QLQ-C30 dimensions. Multiple linear regression models were used to assess the relationship between the score of the EORTC QLQ-C30 questionnaire and gender.

Results

Overall 303 patients (167 male, 136 female) with a diagnosis of CRC were included in the study. The mean age of participants was 58.16±13.58 years. The mean scores of physical (b=-14.80, P=0.001) and social functioning (b=-9.14, P=0.038) of women with CRC were more negatively affected than men with CRC. In addition, women had a higher mean score in pain (b=10.74, P=0.022) and fatigue (b=12.53, P=0.007) symptom subscales in comparison to men. Based on the results of multivariate linear regression analysis, gender, occupation, and adjuvant therapy can be considered as the independent and strong predictor factors of functional scale in our CRC patients.

Conclusions

Women appear to be more affected than men by impaired physical and social functioning after the development of cancer, and they reported more fatigue and pain than men. Therefore, it might be advisable to consider strategies to improve the HRQOL in women.

Same-Day Regimen as an Alternative to Split Preparation for Colonoscopy: A Systematic Review with Meta-Analysis

Background

Split bowel preparation is the best regimen for colonoscopy. However, the same-day regimen can represent a valid alternative, but its use is limited by concerns about its cleansing ability, and to date, no convincing data support its use for routine colonoscopies.

Aim

To evaluate the cleansing, compliance, and adverse event rates of the same-day compared to the split regimen.

Results

A systematic literature search and meta-analysis was performed. Ten studies were included for a total of 1807 patients (880 in the same-day group and 927 in the split group). Overall, 85.3% patients in the same-day group vs. 86.3% in the split group had an adequate cleansing. Compliance was high for both, although patients were more compliant with the split than with the same-day prep (89.7% for same-day vs. 96.6% for split regimen). Sleep disturbance was more frequent in the split group, while nausea and vomit were more frequent in the same-day group. In the subgroup analysis, polyethylene glycol obtained a better cleansing rate when given as a split dose, with similar compliance and adverse events rates with both regimens.

Conclusion

Split and same-day regimens are both useful in bowel cleaning before colonoscopy with a different pattern of adverse events and better compliance for split preparations. Endoscopists can consider the same-day preparation as a valid alternative, especially when the split preparation does not fit the patients' needs.

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.

Risk of Colorectal Cancer in Chronic Kidney Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Association between chronic kidney disease and colorectal cancer (CRC) remains unclear.

GOALS

To assess the risk of CRC in patients with various chronic kidney diseases before and after kidney transplantation.

STUDY

Electronic databases were searched for cohort studies assessing the risk of CRC in patients with chronic kidney diseases. The primary outcome was the risk of CRC among studies that reported the risk as standardized incidence rate (SIR).

RESULTS

Fifty-four studies, including 1,208,767 patients that reported the incidence of CRC in chronic kidney diseases were identified. SIR of CRC were obtained from 17 retrospective cohort studies. Among the 3 studies (4 reports) that included chronic kidney disease patients without kidney transplantation, there was a significant increased risk of CRC (pooled SIR 1.18) (95% confidence interval, 1.01-1.37; P=0.033). High heterogeneity was seen (I=85.6%), and metaregression showed that there were positive correlations between the risk of CRC and the proportions of males, age and follow-up period. Among the 15 studies (17 reports) that included postkidney transplant patients, the pooled SIR was significantly increased at 1.40 (95% confidence interval, 1.15-1.71; P=0.00080). High heterogeneity was seen (I=88.9%), and metaregression showed that the follow-up period correlated with the risk of CRC.

CONCLUSIONS

In the present systematic review and meta-analysis, we demonstrated that patients with chronic kidney disease, regardless of a history of transplant, have a significant increased risk of CRC. A more intensive surveillance for CRC is required in this population.

Proportion of patients who disclose their sexual orientation to healthcare providers and its relationship to patient outcomes: A meta-analysis and review

OBJECTIVE

Patient-centered care emphasizes the need to form a therapeutic and trusting relationship between patients and providers in which patients feel comfortable disclosing health-relevant and personal information. It is still unknown how many patients disclose their sexual orientation to providers, under what circumstances and what it is related to in terms of outcomes.

METHOD

The present meta-analysis and review sought to identify the overall proportion of sexual orientation disclosure to healthcare providers, facilitators and barriers of disclosure, patient populations less likely to disclose, and the relationship between disclosure and outcomes. Thirty-five studies met the inclusion criteria yielding 38 independent proportions. Characteristics of patients, providers, location, and disclosure were extracted.

RESULTS

Sexual orientation disclosure proportions to healthcare providers ranged from .29 to .98. The random-effects pooled estimate was .63 (95% CI: .58, .68). Disclosure compared to nondisclosure was related to more positive direct and indirect health outcomes including higher satisfaction, more healthcare seeking and screenings and better self-reported health and psychological wellbeing.

CONCLUSION

The overall proportion of disclosure to healthcare providers varied by patient, provider, location, and disclosure characteristics.

PRACTICE IMPLICATIONS

These findings emphasize the need for future interventions directed at facilitating disclosure among populations identified as less likely to disclose.

Validation of Assaying Carcinoembryonic Antigen in Human Serum by Using Immunomagnetic Reduction

Immunomagnetic reduction (IMR) is a method to assay biomolecules by utilizing antibody functionalized magnetic nanoparticles. For clinical validation, important analytic performances of assaying carcinoembryonic antigen (CEA) using IMR are characterized. Furthermore, IMR is applied to assay carcinoembryonic antigen (CEA) in human serum for clinical validation. A total of 118 healthy controls and 79 patients with colorectal cancer (CRC) are recruited in this study. For comparison, assays using chemiluminometric immunoassay (CLIA) are also done for quantizing CEA in these serum samples. The results reveal a high correlation in terms of serum CEA concentration detected via IMR and CLIA is found (r = 0.963). However, IMR shows higher clinical sensitivity and specificity than those of CLIA. Moreover, the rate of false positives for smoking subjects is clearly reduced through the use of IMR. All the results demonstrate IMR is a promising alternative assay for serum CEA to diagnose CRC.

Noninvasive Biomarkers of Colorectal Cancer: Role in Diagnosis and Personalised Treatment Perspectives

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths worldwide. It has been estimated that more than one-third of patients are diagnosed when CRC has already spread to the lymph nodes. One out of five patients is diagnosed with metastatic CRC. The stage of diagnosis influences treatment outcome and survival. Notwithstanding the recent advances in multidisciplinary management and treatment of CRC, patients are still reluctant to undergo screening tests because of the associated invasiveness and discomfort (e.g., colonoscopy with biopsies). Moreover, the serological markers currently used for diagnosis are not reliable and, even if they were useful to detect disease recurrence after treatment, they are not always detected in patients with CRC (e.g., CEA). Recently, translational research in CRC has produced a wide spectrum of potential biomarkers that could be useful for diagnosis, treatment, and follow-up of these patients. The aim of this review is to provide an overview of the newer noninvasive or minimally invasive biomarkers of CRC. Here, we discuss imaging and biomolecular diagnostics ranging from their potential usefulness to obtain early and less-invasive diagnosis to their potential implementation in the development of a bespoke treatment of CRC.

Significance of PITX2 Promoter Methylation in Colorectal Carcinoma Prognosis

BACKGROUND

New treatment modalities and a growing understanding of the complex genetic tumor landscape have improved the outcome of colorectal cancer (CRC) patients. Nonetheless, more individualized treatment regimens, taking individual tumor characteristics into account, have been recently postulated and prognostic biomarkers are needed. We therefore evaluated the prognostic potential of paired-like homeodomain transcription factor 2 (PITX2) promoter methylation in CRC patients.

MATERIALS AND METHODS

Data of 2 independent cohorts were investigated. Tissue specimens of cohort A (n = 179) were analyzed for their methylation in the PITX2 promoter region using quantitative methylation-specific polymerase chain reaction and compared with publicly available data (PITX2 promoter methylation and PITX2 mRNA expression levels) from "The Cancer Genome Atlas Research Network" (cohort B, n = 443). Data were correlated with clinicopathological parameters and outcome.

RESULTS

Tumor samples of both cohorts showed a decreased PITX2 promoter methylation level (both P < .001) compared with nonmalignant tissue. Additionally, PITX2 promoter hypomethylation was prognostic in univariate and multivariate analysis (hazard ratio [HR], 1.97 [95% confidence interval (CI), 1.12-3.47], P = .018 and HR, 1.89 [95% CI, 1.09-3.29], P = .023), and Kaplan-Meier analysis (median overall survival, 53.2 vs. 70.4 months, P = .004). Subanalysis of high-risk vs. low-risk stage II CRC patients also showed a PITX2 hypomethylation of the promoter region in the high-risk group (P = .006).

CONCLUSION

Our results suggest a prognostic role of PITX2 promoter methylation in CRC as biomarker for risk stratification in stage II CRC patients although the results need to be independently validated.

Cell-Free Circulating Methylated SEPT9 for Noninvasive Diagnosis and Monitoring of Colorectal Cancer

Identification of early-stage tumor and monitoring therapeutic efficacy and recurrence or metastasis of colorectal cancer (CRC) are urgently warranted for improving the outcome of CRC patients and reducing the disease-related mortality. In this study, we evaluated the diagnostic value of cell-free circulating methylated SEPT9 (mSEPT9) for CRC and beyond CRC and examined the potentiality of mSEPT9 in assessing therapeutic efficacy and monitoring recurrence of CRC. Our results confirmed the favorable diagnostic value of plasma mSEPT9 for CRC, with a sensitivity of 61.22% (95% confidence interval (CI): 51.33%–70.27%) and specificity of 93.7% (95% CI: 91.09%–95.57%) using 2/3 algorithm. The positive rate of mSEPT9 in CRC was correlated with tumor size, histological grade, and general histological type (P < 0.05). Beyond CRC, gastric cancer patients also presented a high positive rate of plasma mSEPT9 (70%). The conversions between preoperative and postoperative plasma mSEPT9 reflected the therapeutic efficacy of curatively intended surgery for CRC patients. The persistent positivity of plasma mSEPT9 after surgery (within 7–14 days) was highly associated with impending recurrences or metastases (within one year), with a sensitivity of 100%. Postoperative mSEPT9 status during follow-up also provided valuable indication for CRC recurrence or metastases, with a good consistency (kappa = 0.818, P = 0.001). Our results verified the reliability of plasma mSEPT9 as a biomarker for noninvasive diagnosis of CRC. More significantly, we revealed its valuable role in appraising CRC therapeutic efficacy and monitoring CRC recurrences or metastases. Further studies with larger sample sizes are needed to verify and elucidate the clinical utility of the promising findings.

Effect of left lateral tilt-down position on cecal intubation time: a 2-center, pragmatic, randomized controlled trial

BACKGROUND AND AIMS

Colonoscopy insertion is technically challenging, time-consuming, and painful, especially for the sigmoid. Several pilot studies indicated that the (left) tilt-down position could facilitate the insertion procedure, but no formal trials have been published to demonstrate its efficacy. We performed this study to verify the benefits of the left lateral tilt-down position (LTDP) on the insertion process.

METHODS

This 2-center prospective trial randomized unsedated patients to the LTDP or left lateral horizontal position (LHP) to aid insertion. The primary outcome measure was cecal intubation time (CIT). Secondary outcome measures included decending colon intubation time (DIT), pain score of insertion, acceptance of unsedated colonoscopy for future examinations, difficulty score for insertion, and the adverse event rate of colonoscopy.

RESULTS

Two hundred fifty-eight patients were randomized to the LTDP (128) or LHP (130) in 2 centers. The median CIT and DIT were shorter with patients positioned in LTDP than in LHP (CIT, 280.0 vs 339.5 s, P < .001; DIT, 53.0 vs 69.0 s, P < .001, respectively) and patients with high and low body mass index (BMI) benefited more from LTDP than from LHP, as opposed to patients with normal BMI. In addition, colonoscopy insertion in LTDP was less painful (3.4 ± 1.6 vs 4.0 ± 1.7, P = .02) and less difficult (3.1 ± 1.9 vs 3.7 ± 1.4, P < .001), showing a higher tendency to acceptance of unsedated colonoscopy (82.9% vs 73.8%, P = .08). The rates of adverse events were extremely low and did not differ significantly in the 2 groups.

CONCLUSIONS

LTDP for colonoscopy insertion can reduce insertion time and pain, and potentially improves patients' acceptance of unsedated colonoscopy. (Clinical trial registration number: NCT02842489.).

Advance in plasma SEPT9 gene methylation assay for colorectal cancer early detection

This review article summarizes the research advances of the plasma-based SEPT9 gene methylation assay for the clinical detection of colorectal cancer and its limitations. Colorectal cancer is a common malignancy with a poor prognosis and a high mortality, for which early detection and diagnosis are particularly crucial for the high-risk groups. Increasing evidence supported that SEPT9 gene methylation is associated with the pathogenesis of colorectal cancer and that detecting the level of methylation of SEPT9 in the peripheral blood can be used for screening of colorectal cancer in susceptible populations. In recent years, the data obtained in clinical studies demonstrated that the SEPT9 gene methylation assay has a good diagnostic performance with regard to both sensitivity and specificity with the advantage of better acceptability, convenience and compliance with serological testing compared with fecal occult blood tests and carcinoembryonic antigen for colorectal cancer (CRC). Furthermore, the combination of multiple methods or markers has become a growing trend for CRC detection and screening. Nevertheless, the clinical availability of the methylated SEPT9 assay is still limited because of the large degree of sample heterogeneity caused by demographic characteristics, pathological features, comorbidities and/or technique selection. Another factor is the cost-effectiveness of colorectal cancer screening strategies that hinders its large-scale application. In addition, improvements in its accuracy in detecting adenomas and premalignant polyps are required.

Upregulation of miR‑598 promotes cell proliferation and cell cycle progression in human colorectal carcinoma by suppressing INPP5E expression

Colorectal cancer (CRC) is one of the most common types of cancer worldwide. Recently, microRNAs (miRs) have been considered as novel therapeutic targets for the treatment of cancer. miR‑598 is a poorly investigated miR. The underlying mechanism of miR‑598 in CRC cells remains to be elucidated. In the present study, miR‑598 was demonstrated to be significantly upregulated in CRC tissue by analyzing data from The Cancer Genome Atlas and the Gene Expression Omnibus. The results of a polymerase chain reaction demonstrated that miR‑598 expression was significantly upregulated in CRC tissues and cells. Gain of function and loss of function assays demonstrated that miR‑598 significantly promoted cell proliferation and cell cycle progression. miR‑598 was demonstrated to modulate cell functions by regulating 72 kDa inositol polyphosphate‑5‑phosphatase (INPP5E). In addition, knockdown of INPP5E counteracted the growth arrest caused by an miR‑598‑inhibitor. In conclusion, the present study demonstrated that miR‑598 contributed to cell proliferation and cell cycle progression in CRC by targeting INPP5E.

Molecular Imaging of Colorectal Tumors by Targeting Colon Cancer Secreted Protein-2 (CCSP-2)

A versatile biomarker for detecting colonic adenoma and colon cancer has yet to be developed. Colon cancer secreted protein-2 (CCSP-2) is a protein specifically expressed and secreted in colon adenomas and cancers. We developed a fluorescent imaging method based on CCSP-2 targeting for a more sensitive and specific detection of colorectal tumors. CCSP-2 expression was evaluated in human colon adenoma and colorectal specimens. Anti–CCSP-2 antibody was labeled with a near-infrared fluorescent dye, FPR-675, and molecular imaging of surgical human colorectal tumors was performed. Immunohistochemistry identified CCSP-2 expression in 87.0% of colorectal cancer specimens and 89.5% of colon adenoma specimens. Fluorescence imaging of surgical human colon specimens after spraying treatment with the probe permitted a clear distinction of cancer from paired normal colon tissue (target-to-background ratio, 4.09 ± 0.42; P < .001). CCSP-2 targeting imaging was also evaluated in patient-derived colon cancer xenograft mouse and liver metastasis murine models. CCSP-2–positive colon cancer xenografts and liver metastases were visualized by near-infrared fluorescence imaging after intravenous injection of the probe, which showed significantly higher fluorescence. Our results show that CCSP-2 is a promising marker for colorectal tumor detection in clinical settings and that a CCSP-2–targeting molecular imaging strategy might improve the diagnosis of colorectal tumors in metastatic or recurrent cancers and aid in early colonoscopic detection of premalignant lesions.

The more from East-Asian, the better: risk prediction of colorectal cancer risk by GWAS-identified SNPs among Japanese

BACKGROUND

Little is known about the difference of genetic predisposition for CRC between ethnicities; however, many genetic traits common to colorectal cancer have been identified. This study investigated whether more SNPs identified in GWAS in East Asian population could improve the risk prediction of Japanese and explored possible application of genetic risk groups as an instrument of the risk communication.

METHODS

558 Patients histologically verified colorectal cancer and 1116 first-visit outpatients were included for derivation study, and 547 cases and 547 controls were for replication study. Among each population, we evaluated prediction models for the risk of CRC that combined the genetic risk group based on SNPs from GWASs in European-population and a similarly developed model adding SNPs from GWASs in East Asian-population. We examined whether adding East Asian-specific SNPs would improve the discrimination.

RESULTS

Six SNPs (rs6983267, rs4779584, rs4444235, rs9929218, rs10936599, rs16969681) from 23 SNPs by European-based GWAS and five SNPs (rs704017, rs11196172, rs10774214, rs647161, rs2423279) among ten SNPs by Asian-based GWAS were selected in CRC risk prediction model. Compared with a 6-SNP-based model, an 11-SNP model including Asian GWAS-SNPs showed improved discrimination capacity in Receiver operator characteristic analysis. A model with 11 SNPs resulted in statistically significant improvement in both derivation (P = 0.0039) and replication studies (P = 0.0018) compared with six SNP model. We estimated cumulative risk of CRC by using genetic risk group based on 11 SNPs and found that the cumulative risk at age 80 is approximately 13% in the high-risk group while 6% in the low-risk group.

CONCLUSION

We constructed a more efficient CRC risk prediction model with 11 SNPs including newly identified East Asian-based GWAS SNPs (rs704017, rs11196172, rs10774214, rs647161, rs2423279). Risk grouping based on 11 SNPs depicted lifetime difference of CRC risk. This might be useful for effective individualized prevention for East Asian.

Colorectal cancer screening: An updated review of the available options

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. However, colon cancer incidence and mortality is declining over the past decade owing to adoption of effective screening programs. Nevertheless, in some parts of the world, CRC incidence and mortality remain on the rise, likely due to factors including “westernized” diet, lifestyle, and lack of health-care infrastructure and resources. Participation and adherence to different national screening programs remain obstacles limiting the achievement of screening goals. Different modalities are available ranging from stool based tests to radiology and endoscopy with varying sensitivity and specificity. However, the availability of these tests is limited to areas with high economic resources. Recently, FDA approved a blood-based test (Epi procolon^®) for CRC screening. This blood based test may serve to increase the participation and adherence rates. Hence, leading to increase in colon cancer detection and prevention. This article will discuss various CRC screening tests with a particular focus on the data regarding the new approved blood test. Finally, we will propose an algorithm for a simple cost-effective CRC screening program.

A Highly Predictive Model for Diagnosis of Colorectal Neoplasms Using Plasma MicroRNA: Improving Specificity and Sensitivity

OBJECTIVE

To develop a plasma-based microRNA (miRNA) diagnostic assay specific for colorectal neoplasms, building upon our prior work.

BACKGROUND

Colorectal neoplasms [colorectal cancer (CRC) and colorectal advanced adenoma (CAA)] frequently develop in individuals at ages when other common cancers also occur. Current screening methods lack sensitivity, specificity, and have poor patient compliance.

METHODS

Plasma was screened for 380 miRNAs using microfluidic array technology from a "Training" cohort of 60 patients, (10 each) control, CRC, CAA, breast cancer, pancreatic cancer, and lung cancer. We identified uniquely dysregulated miRNAs specific for colorectal neoplasia (P < 0.05, false discovery rate: 5%, adjusted α = 0.0038). These miRNAs were evaluated using single assays in a "Test" cohort of 120 patients. A mathematical model was developed to predict blinded sample identity in a 150 patient "Validation" cohort using repeat-sub-sampling validation of the testing dataset with 1000 iterations each to assess model detection accuracy.

RESULTS

Seven miRNAs (miR-21, miR-29c, miR-122, miR-192, miR-346, miR-372, and miR-374a) were selected based upon P value, area under the curve (AUC), fold change, and biological plausibility. Area under the curve (±95% confidence interval) for "Test" cohort comparisons were 0.91 (0.85-0.96) between all neoplasia and controls, 0.79 (0.70-0.88) between colorectal neoplasia and other cancers, and 0.98 (0.96-1.0) between CRC and colorectal adenomas. In our "Validation" cohort, our mathematical model predicted blinded sample identity with 69% to 77% accuracy, 67% to 76% accuracy, and 86% to 90% accuracy for each comparison, respectively.

CONCLUSIONS

Our plasma miRNA assay and prediction model differentiate colorectal neoplasia from patients with other neoplasms and from controls with higher sensitivity and specificity compared with current clinical standards.

Effectiveness of Screening Modalities in Colorectal Cancer: A Network Meta-Analysis

The aim of the study was to evaluate on the effectiveness of screening modalities in the prevention of colorectal cancer (CRC) occurrence and deaths. General meta-analysis was performed to produce pooled estimates of the effect of CRC incidence and mortality using a search of PubMed, Web of Science, and the Cochrane Library for eligible studies from January 1992 to March 2016. A network meta-analysis was performed to synthetically compare the effectiveness of 5 frequently used screening modalities. A total of 44 studies with a focus on mortality from CRC using different screening methods were included. General meta-analysis showed that fecal immunohistochemical testing (FIT), flexible sigmoidoscopy (FS), colonoscopy, combination of fecal occult blood testing and FS screening respectively reduced CRC mortality by 59% (relative risk [RR], 0.41; 95% confidence interval [CI], 0.29-0.59), 33% (RR, 0.67; 95% CI, 0.58-0.78), 61% (RR, 0.39; 95% CI, 0.31-0.50), 38% (RR, 0.62; 95% CI, 0.42-0.91) compared with no screening, whereas guaiac fecal occult blood testing (gFOBT) reduced CRC-related mortality by 14% (RR, 0.86; 95% CI, 0.82-0.90). Subgroup analysis showed that summary estimates of reduction in distal CRC mortality and proximal CRC mortality were 26% (95% CI, 62%-89%) and 10% (95% CI, 83%-98%). A network meta-analysis revealed rank probability analysis in which the colonoscopy had a 94.6% probability of being the most effective examination to reduce CRC mortality. In addition, the network meta-analysis estimated odds ratio, which was a 79% reduction (95% CI, 0.09-0.60) in CRC mortality when screening with FIT was compared with annual or biennial gFOBT and colonoscopy was approximately 80% more effective than gFOBT for reducing CRC mortality (RR, 0.25; 95% CI, 0.13-0.54). Analysis of the effects of different screening methods showed that there was a significant reduction in the incidence of colon cancer, excluding gFOBT. This meta-analysis confirmed that gFOBT, FIT, FS, and colonoscopy were all effective in preventing CRC deaths and a major reduction in distal but not proximal CRC mortality was found. In addition, they were more effective in preventing CRC incidence in addition to gFOBT. The network meta-analysis suggests that colonoscopy is the most effective screening for preventing CRC deaths.

High prevalence of mutant KRAS in circulating exosome-derived DNA from early-stage pancreatic cancer patients

Background

Exosomes arise from viable cancer cells and may reflect a different biology than circulating cell-free DNA (cfDNA) shed from dying tissues. We compare exosome-derived DNA (exoDNA) to cfDNA in liquid biopsies of patients with pancreatic ductal adenocarcinoma (PDAC).

Patients and methods

Patient samples were obtained between 2003 and 2010, with clinically annotated follow up to 2015. Droplet digital PCR was performed on exoDNA and cfDNA for sensitive detection of KRAS mutants at codons 12/13. A cumulative series of 263 individuals were studied, including a discovery cohort of 142 individuals: 68 PDAC patients of all stages; 20 PDAC patients initially staged with localized disease, with blood drawn after resection for curative intent; and 54 age-matched healthy controls. A validation cohort of 121 individuals (39 cancer patients and 82 healthy controls) was studied to validate KRAS detection rates in early-stage PDAC patients. Primary outcome was circulating KRAS status as detected by droplet digital PCR. Secondary outcomes were disease-free and overall survival.

Results

KRAS mutations in exoDNA, were identified in 7.4%, 66.7%, 80%, and 85% of age-matched controls, localized, locally advanced, and metastatic PDAC patients, respectively. Comparatively, mutant KRAS cfDNA was detected in 14.8%, 45.5%, 30.8%, and 57.9% of these individuals. Higher exoKRAS MAFs were associated with decreased disease-free survival in patients with localized disease. In the validation cohort, mutant KRAS exoDNA was detected in 43.6% of early-stage PDAC patients and 20% of healthy controls.

Conclusions

Exosomes are a distinct source of tumor DNA that may be complementary to other liquid biopsy DNA sources. A higher percentage of patients with localized PDAC exhibited detectable KRAS mutations in exoDNA than previously reported for cfDNA. A substantial minority of healthy samples demonstrated mutant KRAS in circulation, dictating careful consideration and application of liquid biopsy findings, which may limit its utility as a broad cancer-screening method.

Screening for colorectal cancer

This review will comprise a general overview of colorectal cancer (CRC) screening. We will cover the impact of CRC, CRC risk factors, screening modalities, and guideline recommendations for screening in average-risk and high-risk individuals. Based on this data, we will summarize our approach to CRC screening.

Diagnostic Accuracy of Methylated SEPT9 for Blood-based Colorectal Cancer Detection: A Systematic Review and Meta-Analysis

Objectives:

More convenient and effective blood-based methods are believed to increase colorectal cancer (CRC) detection adoption. The effectiveness of methylated SPET9 for CRC detection has been reviewed in the newly published recommendation statement by US Preventive Services Task Force (USPSTF), while detailed instructions were not provided, which may be a result of insufficient evidence. Therefore, more evidence is needed to assist practitioners to thoroughly understand the utilization of this special maker.

Methods:

Based on the standard method, a systematic review and meta-analysis was performed. Quadas-2 was used to assess the methodological quality of studies. Relevant studies were searched and screened from PubMed, Embase and other literature databases up to June 1, 2016. Pooled sensitivity, specificity and diagnostic odds ratio were summarized by bivariate mixed effect model and area under the curve (AUC) was estimated by hierarchical summary receiver operator characteristic curve.

Results:

25 studies were included for analysis. The pooled sensitivity, specificity and AUC were 0.71, 0.92 and 0.88, respectively. Among the various methods and assays, Epipro Colon 2.0 with 2/3 algorithm was the most effective in colorectal cancer detection. Positive ratio of mSEPT9 was higher in advanced CRC (45% in I, 70% in II, 76% in III, 79% in IV) and lower differentiation (31% in high, 73% in moderate, 90% in low) tissue. However, this marker has poor ability of identifying precancerous lesions according to current evidence.

Conclusions:

mSEPT9 is a reliable blood-based marker in CRC detection, particularly advanced CRC. Epipro Colon 2.0 with 2/3 algorithm is currently the optimal method and assay to detect CRC.