Colonoscopy and colorectal cancer incidence and mortality

Association between trends of mortality and incidence, survival and stage at diagnosis for six digestive and respiratory cancers in United States (2009-2013)

BACKGROUND

A decrease in cancer mortality has been reported in the USA, possibly due to decreased incidence, downstaging and improved survival. The aim of the present study is to estimate the contribution of these factors on the trend in cancer mortality.

METHODS

Data on incidence, mortality, stage at diagnosis, and overall and stage-specific survival for six common digestive and respiratory cancers (esophagus, stomach, colorectal, liver, pancreas and lung) during 2009-2013 in the USA from the surveillance, epidemiology and end results (SEER) program, was analyzed using generalized linear models separately among men and women.

RESULTS

Our study showed a decrease in mortality for esophageal (-0.09/100 000/year and -0.03/100 000/year), stomach (-0.11/100 000/year and -0.05/100 000/year), colorectal (-0.45/100 000/year and -0.29/100 000/year) and lung cancer (-1.89/100 000/year in men and -0.78/100 000/year in women) in men and women, respectively: for all of them, except lung cancer in women, there was a decrease in the incidence of comparable or greater magnitude; stage distribution and survival also contributed to the decrease in mortality for lung and colorectal cancer. Mortality from pancreatic cancer was stable: an increase in incidence was counterbalanced by an improvement in survival. Mortality from liver cancer increased, driven by an increase in mortality that was not offset by favorable trends in stage distribution and survival.

CONCLUSIONS

Trends in mortality were primarily affected by changes in incidence; an increase in the proportion of local stage at diagnosis and improved survival, although evident for some cancers, played a lesser role in mortality trends.

Education and gastroenterology fellow knowledge about endoscopic mucosal resection of colon adenomas: a survey-based study

Background and study aims  Endoscopic mucosal resection (EMR) is an effective way to remove large (> 2 cm) colon adenomas. Training about it has not been standardized in fellowship programs. This study was aimed at evaluating the education and knowledge of gastroenterology fellows about EMR of colorectal adenomas. Methods  Participation in this survey was offered to 1730 gastroenterology fellows in the United States during the academic year 2019 to 2020. The survey assessed endoscopic mucosal resection training and knowledge and was approved and administered by the American College of Gastroenterology. Results  A total of 163 fellows (9.4 %) completed the survey. Only 85 fellows (52.1 %) reported receiving formal education in endoscopic mucosal resection. Fellow confidence was lowest regarding knowing electrosurgery unit settings. Fewer fellows correctly identified Paris 0-IIb (79, 48.5 %; P  < 0.0001) or NICE I (114, 69.9 %; P  < 0.01) lesions as compared to other Paris and NICE III lesions, respectively. Only 73 (44.8 %) and 93 fellows (57.1 %) arranged steps of EMR in the correct order and identified the correct type of current used for resection, respectively. Training year, male sex, and provision of advanced endoscopy rotations during fellowship were associated with a higher knowledge score for EMR. Conclusions  Nearly half of all fellows reported no formal education in EMR and incorrectly ordered its steps. Adenoma assessment by Paris and NICE classifications and electrosurgery unit settings were the most prominent knowledge deficiencies. Incorporation of standardized training about EMR with inclusion of advanced endoscopy rotations appears to be an important educational opportunity during gastroenterology fellowship.

Crocin has pharmacological effects against the pathological behavior of colon cancer cells by interacting with the STAT3 signaling pathway

The aim of the present study was to investigate changes in proliferation, apoptosis, inflammation and chemokine release of colon cancer cells after treatment with crocin, as well as to investigate the signaling pathway that is regulated by crocin. The inhibition rates of different doses of crocin on the proliferation of HCT116 cells were measured by MTT assay. The IC₅₀ was calculated from the inhibition rates at 48 h. Proliferation curves of HCT116 cells were plotted after treatment with 271.18 µM (high-dose group) or 135.6 µM (low-dose group) crocin. Flow cytometry and Hoechst 33342/propidium iodide double staining were used for detecting apoptosis. ELISA was used to measure the levels of macrophage inflammatory protein 2, interleukin (IL)-8, monocyte chemoattractant protein 1, tumor necrosis factor-α, IL-6 and IL-1β in the supernatant from cultured HCT116 cells following both high- and low-dose crocin treatment. Phosphorylated (P)-STAT3/STAT3 in HCT116 cells were measured by western blotting. Crocin inhibited the proliferation of HCT116 cells in a dose-dependent manner and the high-dose treatment with crocin resulted in a lower rate of proliferation. Additionally, crocin increased the apoptosis of HCT116 cells and the high-dose treatment with crocin led to a higher level of apoptosis. Notably, crocin decreased the secretion of chemokines and inflammatory factors from HCT116 cells and the high-dose treatment with crocin caused the greatest reduction in secretion of the factors. Crocin reduced the ratio of P-STAT3/STAT3, and thereby reduced the release of cytokines. The present study demonstrated that crocin may have pharmacological effects against the pathological behavior of colon cancer cells, and its mechanism of action may be related to the STAT3 signaling pathway.

Fluoroscopy-guided long intestinal tube placement for the treatment of malignant bowel obstruction

The aim of the present study was to investigate the safety and efficacy of long intestinal tube placement under fluoroscopic guidance for the treatment of malignant bowel obstruction (MBO). The cases of 74 patients with MBO who underwent long intestinal tube placement under fluoroscopic guidance during the period between June 2015 and October 2017 were reviewed. The clinical characteristics were retrospectively analysed with respect to efficacy, safety and outcome. Long intestinal tube placement was successfully completed in all 74 patients. The mean time required for tube placement was 31.09±16.25 min and the mean insertion depth of the tube was 153±39 cm. In 58 cases, the symptoms of abdominal pain, abdominal bloating and vomiting were greatly improved following 1-3 days of tube decompression. The symptoms of the remaining 16 patients were not effectively relieved following decompression. No serious complications were observed in any patients. Overall, for patients with severe MBO, long intestinal tube placement under fluoroscopic guidance appears to be an effective and safe treatment, and it may improve quality of life.

Kidney injury and other complications related to colonoscopy in inpatients at a tertiary teaching hospital

OBJECTIVES

To describe clinical complications related to colonoscopy in inpatients with multiple diseases. Among the known complications, acute kidney injury was the primary focus.

METHODS

This was an observational retrospective study of 97 inpatients. Data relating to age; gender; comorbidities; current medication; blood tests (renal function, blood glucose and LDL cholesterol levels); length of hospital stay; indication, results, and complications of colonoscopies; and time to the development of kidney injury were collected between June 2011 to February 2012.

RESULTS

A total of 108 colonoscopies (9 screening and 88 diagnostic) were conducted in 97 patients. Renal injury occurred in 41.2% of the patients. The univariate analysis revealed that kidney injury was related to the use of diuretics, statins, calcium channel blockers, and angiotensin converting enzyme inhibitor; however, the multivariate analysis showed that only the use of diuretics was associated with kidney injury. The occurrence of kidney injury and the time to its development were independent of the previous glomerular filtration rate as calculated with the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.

CONCLUSIONS

The use of diuretics was the only independent variable associated with the development of kidney injury in inpatients with multiple comorbidities who underwent colonoscopy. The occurrence of kidney injury and the time to its development were independent of previous CKD-EPI-based assessments of renal function. These results highlight the increased risk of colonoscopy in such patients, and its indication should be balanced strictly and perhaps avoided as a screening test.

Distant Liver Metastases as a Major Factor Influencing Survival in Patients with Colorectal Cancer

AIM

To assess the effect of the factor 'hepatic metastatic disease' on long-term outcomes in patients with colorectal cancer.

MATERIALS AND METHODS

We analysed retrospectively 200 randomly selected patients. Forty-two of them were excluded from the study for different reasons so the study contingent was 158 patients over a period of 23 years. All were diagnosed and treated in the Lozenetz University Hospital, in the Department of General Surgery. 125 of the patients were diagnosed with colorectal cancer without distant metastases and 33 of the patients had liver metastases as a result of colorectal carcinoma. The statistical analysis was performed using SPSS 19 IMB, with a level of significance of P < 0.05 at which the null hypothesis is rejected. We also used descriptive analysis, Kaplan-Meier estimator, Log-Rank Test and Life-Table statistics models.

RESULTS

The median survival for patients without metastases was 160 months, and the median was 102 months. The median survival for patients with liver metastases was 28 months and the median was 21 months. One-year survival for patients without metastases was 92% versus 69% in patients with liver metastases.

CONCLUSION

Average, annual and median survivals are influenced statistically significantly by the presence of liver metastases compared to overall survival and that of patients without metastatic colorectal cancer. Liver metastatic disease is a proven factor affecting long-term prognosis and survival in patients with colorectal cancer.

Role of microRNA-141 in colorectal cancer with lymph node metastasis

The present study aimed to investigate the role of microRNA (miR)-141 in the pathogenesis of colorectal cancer (CRC). In total, 58 CRC patients were included in the present study. The mRNA and protein expression levels of mitogen-activated protein kinase 4 (MAP4K4) were detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, respectively. The miRNA-141 expression was measured by RT-qPCR, while serum MAP4K4 content was detected by enzyme-linked immunosorbent assay. Natural killer (NK) cells and T cells in peripheral blood were detected by flow cytometry. The results indicated that the mRNA and protein expression levels of MAP4K4 were significantly elevated in the tumor tissues, lymph nodes (P<0.01) and serum (P<0.05) in CRC. Furthermore, the expression levels of MAP4K4 in CRC patients with lymph node metastasis were higher compared with those in patients without metastasis. Bioinformatics analysis revealed that MAP4K4 may be the target gene of miRNA-141. The expression levels of miRNA-141 in the tumor tissues, lymph nodes and serum were significantly decreased in CRC patients, with a more evident decline in cases with lymph node metastasis. In addition, the percentage of NK, CD3⁺ T and CD4⁺ T cells was significantly decreased, whilst the number of CD8⁺ T cells was significantly increased, in the peripheral blood in CRC. The present results showed that miRNA-141 was downregulated in CRC, which increased the expression levels of MAP4K4 and altered the anti-tumor response, further increasing the proliferation, invasion and metastasis of the tumors. These findings may contribute to improving the current understanding of the pathogenesis of CRC, and lead to the development of therapies involving miRNA-141.

Role of self-expanding metal stents in patients with malignant colorectal obstruction: A systematic review and meta-analysis

AIM: To assess the safety and efficacy of self-expandable metal stents (SEMSs) for malignant colorectal obstruction.

METHODS: Data regarding technical success, clinical success, and procedure related complications were collected from included studies. DerSimonian-Laird random effects model was used to generate the overall outcome. Thirty international studies with a total of 2058 patients with malignant colorectal obstruction were included.

RESULTS: The technical and clinical success rates for SEMS placement were 94% (95%CI: 92-96) and 91% (95%CI: 88-93), respectively. Overall complication rate for SEMS was 23% (95%CI: 18-29). Stent migration 8% (95%CI: 6-10) and stent obstruction 8% (95%CI: 6-11) were the most common complications, followed by perforation 5% (95%CI: 4%-7%). Surgical or endoscopic re-interventions were needed in 14% (95%CI: 10-18) of patients. Endoscopic repeat stent placement was required in 8% (95%CI: 6-10), while surgical intervention was needed in 6% (95%CI: 4-8).

CONCLUSION: SEMS are effective when used as palliation or bridge to surgery for malignant colorectal obstruction with high technical and clinical success. About 14% of patients require repeat endoscopic or surgical intervention for stent failure or to manage stent related complications.

Longitudinal Rates of Colon Cancer Screening Use in Winnipeg, Canada: The Experience of a Universal Health-Care System with an Organized Colon Screening Program

OBJECTIVES

We examined trends in colorectal cancer (CRC) screening (fecal occult blood test (FOBT), colonoscopy, and flexible sigmoidoscopy (FS)) and differences in CRC screening by income in a population with an organized CRC screening program and universal health-care coverage.

METHODS

Individuals who had an FOBT, colonoscopy, or FS were identified from the provincial Physician Claims database and the population-based colon cancer screening registry. Trends in age-standardized rates were determined. Logistic regression was performed to explore the association between CRC screening and income quintiles by year.

RESULTS

Up-to-date CRC screening (FOBT, colonoscopy, or FS) increased over time for men and women, all age groups, and all income quintiles. Up-to-date CRC screening was very high among 65- to 69- and 70- to 74-year-olds (70% and 73%, respectively). There was a shift toward the use of an FOBT for CRC screening for individuals in the lower income quintiles. The disparity in colonoscopy/FS coverage by income quintile was greater in 2012 than in 1995. Overall, there was no reduction in disparities by income in up-to-date CRC screening nor did the rate of increase in up-to-date CRC screening or FOBT use change after the introduction of the organized provincial CRC screening program.

CONCLUSIONS

CRC screening is increasing over time for both men and women and all age groups. However, a disparity in up-to-date CRC screening by income persisted even with an organized CRC screening program in a universal health-care setting.

Frequency and efficacy of additional investigations following incomplete colonoscopies: A population-based analysis

BACKGROUND

Limited data are available on the follow-up of patients with incomplete colonoscopy following positive faecal occult blood testing. Our study aimed to determine the proportion of and reasons for incomplete colonoscopies, the proportion of patients who completed colonic evaluations, the methods used and the subsequent findings.

METHODS

A total of 9483 colonoscopies performed after positive testing in a colorectal cancer screening programme setting were included. The study was prospective for index colonoscopy findings and partly retrospective for follow-up.

RESULTS

Overall 297 colonoscopies were incomplete (3.2%). A secondary colonic evaluation was deemed necessary in 245 patients, of which 126 underwent an additional examination (51.4%). Radiology was the primary method used for complete colonic evaluation, whereas a repeat colonoscopy was performed in only 6.4%; the examination was normal in 119 patients (94.4%). A mucosal high-grade neoplasia was removed in 1, and multiple (≥3) adenomas were removed in 2 patients.

CONCLUSIONS

The present screening programme with biennial faecal occult blood testing revealed a high colonoscopy completion rate, a low rate of secondary colonic evaluation, infrequent use of colonoscopy for completion, and a low detection rate of significant neoplasia.

Colonoscopy in Colorectal Cancer Screening: Current Aspects

Colonoscopy represents a very important diagnostic modality for screening for colorectal cancer, because it has the ability to both detect and effectively remove pro-malignant and malignant lesions. It is recommended by almost all international and national gastroenterology and cancer societies, as an initial screening modality or, following a positive fecal occult blood test, to be performed every 10 years in individuals of average risk starting from the age of 50. However, a significant problem is the so-called post-screening (interval) polyps and cancers found some years after the index colonoscopy. In order to reduce the rate of interval cancers it is extremely necessary to optimize the quality and effectiveness of colonoscopy. Bowel preparation is of paramount importance for both accurate diagnosis and subsequent treatment of lesions found on colonoscopy. The quality of bowel preparation could be significantly improved by splitting the dose regimens, a strategy that has been shown to be superior to single-dose regimen. A good endoscopic technique and optimal withdrawal time offering adequate time for inspection, would further optimize the rate of cecal intubation and the number of lesions detected. During the last years, sophisticated devices have been introduced that would further facilitate cecal intubation. The percentage of total colonoscopies is now super-passing the level of 95 % allowing the adenoma detection rate to be greater than the suggestive level of 25 % in men and 15 % in women. This review aims to provide the reader with the current knowledge concerning indications, usefulness, limitations and future perspectives of this probably most important screening technique for colorectal cancer available today.

Screening rates for colorectal cancer in Canada: a cross-sectional study

INTRODUCTION

Implementation of population-based colorectal cancer (CRC) screening programs should reduce disparities in participation in CRC screening. We estimated CRC screening rates in 2012 in Canada and assessed predictors of screening in provinces with and without well-established population-based screening programs.

METHODS

We used data from the Canadian Community Health Survey for 2012 to calculate the prevalence of up-to-date CRC screening, defined as fecal occult blood testing (FOBT) within 2 years before the survey or flexible sigmoidoscopy or colonoscopy within 10 years before the survey, or both. Weighted proportions of individuals with up-to-date screening were calculated and logistic regression analysis performed to assess predictors of up-to-date CRC screening, including differences in participation by income level.

RESULTS

The prevalence of up-to-date CRC screening among people 50-74 years of age in 2012 was 55.2%, ranging from 41.3% in the territories to 67.2% in the province of Manitoba. The rate for sigmoidoscopy or colonoscopy was 37.2% (highest in Ontario, at 43.3%), and for FOBT it was 30.1% (highest in Manitoba, at 51.7%). About 41% of those who had an FOBT also had a sigmoidoscopy or colonoscopy. Individuals in the highest income group were more likely than those in lower-income groups to be up to date with CRC screening, even in provinces with well-established population-based screening programs.

INTERPRETATION

More than half of Canadians were up to date with CRC screening in 2012, but there were large differences among provinces. Differences by income group in provinces with population-based screening programs need particular attention.

Reduced incidence and mortality from colorectal cancer with flexible-sigmoidoscopy screening: A meta-analysis

AIM: To conduct a systematic review and meta-analysis of published population-based randomized controlled trials (RCTs).

METHODS: RCTs evaluating the difference in mortality and incidence of colorectal cancer (CRC) between a screening flexible sigmoidoscopy (FS) group and control group (not assigned to screening FS) with a minimum 5 years median follow-up were identified by a search of MEDLINE and EMBASE databases and the Cochrane Central Register for Controlled Trials through August 2013. Random effects model was used for meta-analysis.

RESULTS: Four RCTs with a total of 165659 patients in the FS group and 249707 patients in the control group were included in meta-analysis. Intention-to-treat analysis showed that there was a 22% risk reduction in total incidence of CRC (RR = 0.78, 95%CI: 0.74-0.83), 31% in distal CRC incidence (RR = 0.69, 95%CI: 0.63-0.75), and 9% in proximal CRC incidence (RR = 0.91, 95%CI: 0.83-0.99). Those who underwent screening FS were 18% less likely to be diagnosed with advanced CRC (OR = 0.82, 95%CI: 0.71-0.94). There was a 28% risk reduction in overall CRC mortality (RR = 0.72, 95%CI: 0.65-0.80) and 43% in distal CRC mortality (RR = 0.57, 95%CI: 0.45-0.72).

CONCLUSION: This meta-analysis suggests that screening FS can reduce the incidence of proximal and distal CRC and mortality from distal CRC along with reduction in diagnosis of advanced CRC.

Systematic review and bivariate/HSROC random-effect meta-analysis of immunochemical and guaiac-based fecal occult blood tests for colorectal cancer screening

BACKGROUND

Current literature evidences higher accuracy of immunological (iFOBT) vis-à-vis guaiac-based (gFOBT) fecal occult blood tests for colorectal cancer (CRC) screening. Few well-designed head-to-head comparisons exist.

AIM

This meta-analysis assesses the performances of two iFOBTs compared with an established gFOBT using colonoscopy as the gold standard.

METHODS

We mobilized a bivariate and a hierarchical summary receiver operating characteristic (HSROC) model. Positive likelihood ratio (LR) and negative likelihood ratio (LR) and diagnostic odds ratios were back-calculated. We constructed bivariate credibility ellipses in the HSROC space and calculated areas under the curve to obtain a global measure of test performance. Estimates are presented at 95% credibility levels.

RESULTS

We included and analyzed 21 studies. OC-Sensor was the best test for CRC screening, with high sensitivity (0.87; 95% credibility interval: 0.73-0.95) and specificity (0.93; 95% credibility interval: 0.84-0.96), optimal LR (12.01) and LR (0.14), and a high diagnostic odds ratio (88.05). Bivariate credibility ellipses showed OC-Sensor's dominance over Hemoccult (sensitivity: 0.47; 95% credibility interval: 0.37-0.58; specificity: 0.93; 95% credibility interval: 0.91-0.95).

CONCLUSION

Our findings support the use of OC-Sensor for CRC detection. The diagnostic estimates obtained may be extended to derive model parameters for economic decision models and to offer insight for future clinical and public health decision making. Our findings could influence the future of FOBTs within the CRC screening arsenal.

Interference of mucin 1 inhibits progression of colon carcinoma by repression of Wnt/β-catenin signaling

Mucin 1 (Muc1) is a tumor-associated glycoprotein and has an important role in cancer progression and metastasis. The aim of the study was to explore the effects and mechanism of Muc1 silencing on proliferation and tumor-forming capacity of colon cancer cell lines. In the present study, we first screened the colon cancer cell lines with high expression of Muc1 by western blot analysis. Then, the effective siRNA was selected and used for silencing endogenous Muc1. The results by MTT and vitro scratch assay showed that interference of Muc1 could effectively inhibit HCC2998 proliferation and migration (p<0.01). Also, colony-forming ability in Muc1-siRNA groups was significantly decreased compared with the control group (p<0.01). Cell cycle is detected by flow cytometry that suggested that Muc1-siRNA1 induced cell cycle arrest at S phase in HCC2998. Next, the expression and distribution of β-catenin in cytoplasm and the nucleus was detected by western blot and the results revealed that the expression of β-catenin was redistributed in Muc1-siRNA group. A higher β-catenin level was detected in cytoplasm, while a lower β-catenin level was located in nucleus, compared with controls (p<0.05). The tumorigenicity experiments showed that inhibition of Muc1 could significantly suppress the growth of HCC2998 in nude mice models (p<0.01). This study would effectively provide new clues for colon cancer therapy.