Trends in colorectal cancer incidence rates in the United States by tumor location and stage, 1992-2008

Colorectal cancer screening: A review of current knowledge and progress in research

Colorectal cancer (CRC) is one of the most prevalent malignancies worldwide, being the third most commonly diagnosed malignancy and the second leading cause of cancer-related deaths globally. Despite the progress in screening, early diagnosis, and treatment, approximately 20%-25% of CRC patients still present with metastatic disease at the time of their initial diagnosis. Furthermore, the burden of disease is still expected to increase, especially in individuals younger than 50 years old, among whom early-onset CRC incidence has been increasing. Screening and early detection are pivotal to improve CRC-related outcomes. It is well established that CRC screening not only reduces incidence, but also decreases deaths from CRC. Diverse screening strategies have proven effective in decreasing both CRC incidence and mortality, though variations in efficacy have been reported across the literature. However, uncertainties persist regarding the optimal screening method, age intervals and periodicity. Moreover, adherence to CRC screening remains globally low. In recent years, emerging technologies, notably artificial intelligence, and non-invasive biomarkers, have been developed to overcome these barriers. However, controversy exists over the actual impact of some of the new discoveries on CRC-related outcomes and how to effectively integrate them into daily practice. In this review, we aim to cover the current evidence surrounding CRC screening. We will further critically assess novel approaches under investigation, in an effort to differentiate promising innovations from mere novelties.

Delineating the role of nuclear receptors in colorectal cancer, a focused review

Colorectal cancer (CRC) stands as one of the most prevalent form of cancer globally, causing a significant number of deaths, surpassing 0.9 million in the year 2020. According to GLOBOCAN 2020, CRC ranks third in incidence and second in mortality in both males and females. Despite extensive studies over the years, there is still a need to establish novel therapeutic targets to enhance the patients' survival rate in CRC. Nuclear receptors (NRs) are ligand-activated transcription factors (TFs) that regulate numerous essential biological processes such as differentiation, development, physiology, reproduction, and cellular metabolism. Dysregulation and anomalous expression of different NRs has led to multiple alterations, such as impaired signaling cascades, mutations, and epigenetic changes, leading to various diseases, including cancer. It has been observed that differential expression of various NRs might lead to the initiation and progression of CRC, and are correlated with poor survival outcomes in CRC patients. Despite numerous studies on the mechanism and role of NRs in this cancer, it remains of significant scientific interest primarily due to the diverse functions that various NRs exhibit in regulating key hallmarks of this cancer. Thus, modulating the expression of NRs with their agonists and antagonists, based on their expression levels, holds an immense prospect in the diagnosis, prognosis, and therapeutical modalities of CRC. In this review, we primarily focus on the role and mechanism of NRs in the pathogenesis of CRC and emphasized the significance of targeting these NRs using a variety of agents, which may represent a novel and effective strategy for the prevention and treatment of this cancer.

Effectiveness of Colonoscopy Screening vs Sigmoidoscopy Screening in Colorectal Cancer

Importance

Randomized clinical screening trials have shown that sigmoidoscopy screening reduces colorectal cancer (CRC) incidence and mortality. Colonoscopy has largely replaced sigmoidoscopy for CRC screening, but long-term results from randomized trials on colonoscopy screening are still lacking.

Objective

To estimate the additional screening benefit of colonoscopy compared with sigmoidoscopy.

Design, Setting, and Participants

This comparative effectiveness simulation study pooled data on 358 204 men and women randomly assigned to sigmoidoscopy screening or usual care in 4 randomized sigmoidoscopy screening trials conducted in Norway, Italy, the US, and UK with inclusion periods in the years 1993 to 2001. The primary analysis of the study was conducted from January 19 to December 30, 2021.

Intervention

Invitation to endoscopic screening.

Main Outcomes and Measures

Primary outcomes were CRC incidence and mortality. Using pooled 15-year follow-up data, colonoscopy screening effectiveness was estimated assuming that the efficacy of colonoscopy in the proximal colon was similar to that observed in the distal colon in the sigmoidoscopy screening trials. The simulation model was validated using data from Norwegian participants in a colonoscopy screening trial.

Results

This analysis included 358 204 individuals (181 971 women [51%]) aged 55 to 64 years at inclusion with a median follow-up time ranging from 15 to 17 years. Compared with usual care, colonoscopy prevented an estimated 50 (95% CI, 42-58) CRC cases per 100 000 person-years, corresponding to 30% incidence reduction (rate ratio, 0.70 [95% CI, 0.66-0.75]), and prevented an estimated 15 (95% CI, 11-19) CRC deaths per 100 000 person-years, corresponding to 32% mortality reduction (rate ratio, 0.68 [95% CI, 0.61-0.76]). The additional benefit of colonoscopy screening compared with sigmoidoscopy was 12 (95% CI, 10-14) fewer CRC cases and 4 (95% CI, 3-5) fewer CRC deaths per 100 000 person-years, corresponding to percentage point reductions of 6.9 (95% CI, 6.0-7.9) for CRC incidence and 7.6 (95% CI, 5.7-9.6) for CRC mortality. The number needed to switch from sigmoidoscopy to colonoscopy screening was 560 (95% CI, 486-661) to prevent 1 CRC case and 1611 (95% CI, 1275-2188) to prevent 1 CRC death.

Conclusions and Relevance

The findings of this comparative effectiveness study assessing long-term follow-up after CRC screening suggest that there was an additional preventive effect on CRC incidence and mortality associated with colonoscopy screening compared with sigmoidoscopy screening, but the additional preventive effect was less than what was achieved by introducing sigmoidoscopy screening where no screening existed. The results probably represent the upper limit of what may be achieved with colonoscopy screening compared with sigmoidoscopy screening.

Construction of the survival nomograms for colon cancer patients of different ages based on the SEER database

INTRODUCTION

Three nomograms for predicting the outcomes of early- and late-onset colon cancer (COCA) among patients not stratified by age were constructed using data in the Epidemiology and End Results (SEER) database (1975-2019). The accuracy of the nomogram was then assessed.

METHOD

Clinical data of 6107 patients with COCA were obtained from the SEER database. The patients were randomly divided into training and validation cohorts in a ratio of 7:3. Univariate and multivariate COX analyses of factors that could independently impact the prognosis of COCA were performed, and the corresponding nomograms for early-onset and late-onset COCA were constructed. Calibration curves, ROC curves, and C-index were used to determine the predictive accuracy. The discriminatory ability of the nomograms to assess their clinical utility, which was compared with the TNM staging system of the 8th edition of AJCC, was verified using survival analysis.

RESULT

Tumor primary site, ethnicity, and serum carcinoembryonic antigen (CEA) level significantly impacted the prognosis of colon cancer. Race, brain metastasis, and CEA were independent factors for predicting COCA prognosis. C-index, ROC, and calibration curves demonstrated that the three nomograms were accurate and superior to the traditional TNM staging system. Among the three nomograms, the early-onset COCA nomogram had the highest predictive accuracy, followed by that of colon cancer not stratified by age.

CONCLUSION

Three nomograms for patients not stratified by age, early-onset colon cancer, and late-onset colon cancer were constructed. The accuracies of the nomograms were good and were all superior to the conventional TNM staging system. The early- and late-onset COCA nomograms are useful for clinical management and individualized treatment of COCA patients at different ages.

Guanylate cyclase-C Signaling Axis as a theragnostic target in colorectal cancer: a systematic review of literature

Introduction

Colorectal cancer (CRC) is a devastating disease that affects millions of people worldwide. Recent research has highlighted the crucial role of the guanylate cyclase-C (GC-C) signaling axis in CRC, from the early stages of tumorigenesis to disease progression. GC-C is activated by endogenous peptides guanylin (GU) and uroguanylin (UG), which are critical in maintaining intestinal fluid homeostasis. However, it has been found that these peptides may also contribute to the development of CRC. This systematic review focuses on the latest research on the GC-C signaling axis in CRC.

Methods

According to the aim of the study, a systematic literature search was conducted on Medline and PubMed databases. Ultimately, a total of 40 articles were gathered for the systematic review.

Results

Our systematic literature search revealed that alterations in GC-C signaling compartments in CRC tissue have demonstrated potential as diagnostic, prognostic, and therapeutic markers. This research highlights a potential treatment for CRC by targeting the GC-C signaling axis. Promising results from recent studies have explored the use of this signaling axis to develop new vaccines and chimeric antigen receptors that may be used in future clinical trials.

Conclusion

The findings presented in this review provide compelling evidence that targeting the GC-C signaling axis may be an advantageous approach for treating CRC.

Elevated Adenomatous Polyp Detection Rate Among Alaska Native and American Indian People in Interior Alaska, 2018-2022

OBJECTIVES

Colorectal cancer (CRC) incidence and mortality are twice as high among Alaska Native people as among non-Hispanic White people in the United States; as such, colonoscopy is a recommended screening test for Alaska Native people. Adenoma detection rate (ADR) is measured in patients at average risk of CRC undergoing initial screening colonoscopy and reflects the prevalence of precancerous polyps in a screened population. We evaluated the ADR among Alaska Native people living in Interior Alaska.

METHODS

This project evaluated the ADR among Alaska Native and American Indian adults aged ≥40 years (N = 460) living in Interior Alaska, using a retrospective medical record review of patients referred for screening colonoscopy from February 1, 2018, through March 31, 2022. The main outcome measure was ADR, stratified by age and sex.

RESULTS

The ADR was 45.0% overall: 43.0% among women and 47.1% among men. Among patients aged ≥50 years, the ADR was 67.1%: 62.7% among women and 70.7% among men. Among patients aged 40-49 years, the ADR was 34.4%: 35.3% among women and 33.3% among men.

CONCLUSIONS

Measured ADR was high among Alaska Native men and women aged ≥50 years in Interior Alaska and in all age groups that were screened. These findings have implications for which CRC screening methods, intervals, and age to begin screening are most appropriate for Alaska Native people, as well as the need for future research on the pathology, etiology, and natural history of CRC in this population.

The accuracy of the FIT in detecting advanced neoplasm is highest in young people aged 40 to 49 years: an analysis based on sex and age

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers and is associated with high incidence and mortality rates worldwide. CRC has caused a tremendous loss of human health and wealth. The incidence and mortality of colorectal carcinoma are increasing in young adults. Early cancer detection and prevention are made possible through screening. At present, the faecal immunochemical test (FIT) is a noninvasive method that can be used for the large-scale clinical screening of CRC status. Therefore, this study, based on CRC screening results in Tianjin from 2012 to 2020, was conducted to analyse the major differences in diagnostic performance parameters according to sex and age.

METHODS

This study was based on 39,991 colonoscopies performed for individuals in the Tianjin CRC screening program from 2012 to 2020. Of these individuals, they had complete FIT and colonoscopy results. The differences in FIT results were analysed by sex and age.

RESULTS

According to this study, males were generally more likely to develop advanced neoplasms (ANs) than females, and the prevalence increased with age. Males with negative FIT results were more likely to have advanced neoplasms than females with positive results. The accuracy of the FIT in detecting ANs in each age group was 54.9%, 45.5%, 48.6% and 49.5% in the 40-49, 50-59, 60-69, and ≥ 70 age groups, respectively.

CONCLUSIONS

The FIT detected ANs with highest accuracy in the 40-49 age group. Our research can provide guidance to formulate CRC screening strategies.

Impact of the COVID-19 pandemic in the early-onset colorectal cancer

The COVID19 pandemic has affected the spectrum of cancer care worldwide. Early onset colorectal cancer (EOCRC) is defined as diagnosis below the age of 50. Patients with EOCRC faced multiple challenges during the COVID19 pandemic and in some institutions it jeopardized cancer diagnosis and care delivery. Our study aims to identify the clinicopathological features and outcomes of patients with EOCRC in our Centre during the first wave of the pandemic in comparison with the same period in 2019 and 2021.

Patients with EOCRC visited for the first time at Vall d'Hebron University Hospital in Spain from the 1st March to 31st August of 2019, 2020 and 2021 were included in the analysis. 177 patients with EOCRC were visited for the first time between 2019 and 2021, of which 90 patients met the inclusion criteria (2019: 30 patients, 2020: 29 patients, 2021: 31 patients). Neither differences in frequency nor in stage at diagnosis or at first visit during the given periods were observed. Of note, indication of systemic therapy in the adjuvant or metastatic setting was not altered. Days to treatment initiation and enrollment in clinical trials in this subpopulation was not affected due to the COVID-19 outbreak.

Deep Learning Empowers Endoscopic Detection and Polyps Classification: A Multiple-Hospital Study

The present study aimed to develop an AI-based system for the detection and classification of polyps using colonoscopy images. A total of about 256,220 colonoscopy images from 5000 colorectal cancer patients were collected and processed. We used the CNN model for polyp detection and the EfficientNet-b0 model for polyp classification. Data were partitioned into training, validation and testing sets, with a 70%, 15% and 15% ratio, respectively. After the model was trained/validated/tested, to evaluate its performance rigorously, we conducted a further external validation using both prospective (n = 150) and retrospective (n = 385) approaches for data collection from 3 hospitals. The deep learning model performance with the testing set reached a state-of-the-art sensitivity and specificity of 0.9709 (95% CI: 0.9646-0.9757) and 0.9701 (95% CI: 0.9663-0.9749), respectively, for polyp detection. The polyp classification model attained an AUC of 0.9989 (95% CI: 0.9954-1.00). The external validation from 3 hospital results achieved 0.9516 (95% CI: 0.9295-0.9670) with the lesion-based sensitivity and a frame-based specificity of 0.9720 (95% CI: 0.9713-0.9726) for polyp detection. The model achieved an AUC of 0.9521 (95% CI: 0.9308-0.9734) for polyp classification. The high-performance, deep-learning-based system could be used in clinical practice to facilitate rapid, efficient and reliable decisions by physicians and endoscopists.

Inhibition of mouse colon cancer growth following immunotherapy with a fraction of hydatid cyst fluid

BACKGROUND

Hydatid cyst is the larval stage of the tape worm Echinococcus granulosus which is located in human and livestock viscera. There are some scientific evidences indicating that parasitic infections induce antitumor activity against certain types of cancers. In this study, the effects of a fraction of hydatid cyst fluid on colon cancer tumor in BALB/c mice were investigated.

MATERIALS AND METHODS

In this experimental work six groups of mice were challenged with mouse colon cancer cells. 5 days later when the sign of tumor growth in mice was seen, group 1-4 were injected with hydatid cyst fluid, the 78 kDa fraction, live protoscolices and BCG respectively. Group five was injected with alum alone and the sixth group left intact without any injection. The size of the tumor was measured and compared in all groups. Then blood samples of mice were evaluated for serum cytokine levels.

RESULT

In mice injected with hydatid cyst antigens especially a fraction of hydatid cyst fluid, tumor size was smaller than the that of control groups and the difference of tumor size in cases and control groups was statistically significant.

CONCLUSION

The results of this study showed that injection of mice with a fraction of hydatid cyst fluid significantly inhibits the growth of mouse colon cancer and this inhibition may be related to effect of immune response to these antigens.

Novel DNA methylation biomarkers in stool and blood for early detection of colorectal cancer and precancerous lesions

BACKGROUND

Early detection and prevention of precancerous lesions can significantly reduce the morbidity and mortality of colorectal cancer (CRC). Here, we developed new candidate CpG site biomarkers for CRC and evaluated the diagnostic value of their expression in blood and stool samples of CRC and precancerous lesions.

METHODS

We analyzed 76 pairs of CRC and adjacent normal tissue samples, 348 stool samples, and 136 blood samples. Candidate biomarkers for CRC were screened using a bioinformatics database and identified using a quantitative methylation-specific PCR method. The methylation levels of the candidate biomarkers were validated using blood and stool samples. The divided stool samples were used to construct and validate a combined diagnostic model and to analyze the independent or combined diagnostic value of candidate biomarkers in stool samples of CRC and precancerous lesions.

RESULTS

Two candidate CpG site biomarkers for CRC, cg13096260 and cg12993163, were identified. Although both biomarkers demonstrated diagnostic performance to a certain extent when using blood samples, they showed better diagnostic value for different stages of CRC and AA with stool samples.

CONCLUSIONS

cg13096260 and cg12993163 detection in stool samples could be a promising approach for screening and early diagnosis of CRC and precancerous lesions.

Use of 2-Stage Modeling to Identify How Colorectal Cancer Risk Changes With Period and Cohort

Colorectal cancer (CRC) incidence rates have decreased among adults aged 50 years or older while increasing in adults under age 50 years. Understanding these trends is challenging because of the multiple related time scales of age, diagnosis period, and birth cohort. We analyzed incidence rates of rectal, distal colon, and proximal colon cancer for individuals aged 20 years or more from the Surveillance, Epidemiology, and End Results Program for diagnosis years 1978-2017. We used a 2-stage generalized linear model to determine age, period, and cohort effects for CRC incidence. We first estimated birth cohort effects among people under age 45 years. We used these results to specify prior distributions for cohort effects in a Bayesian model to estimate period effects among people aged 45 years or more. There was no evidence of period effects for people under age 45 years. Risks of rectal and distal colon cancer increased for later birth cohorts. Compared with the 1943-1952 birth cohort, the 1983-1992 birth cohort had 2.2 times the risk of rectal cancer, 1.9 times the risk of distal colon cancer, and 1.3 times the risk of proximal colon cancer. For people aged ≥45 years, period effects showed declines in CRC risk that were attributable to screening.

Disability-adjusted life years and the trends of the burden of colorectal cancer: a population-based study in Shanghai, China during 2002 to 2016

BACKGROUND

Colorectal cancer (CRC) still ranks the top in morbidity and mortality of cancers worldwide, posing a huge threat and burden to the society. We aimed to determine the age-standardized incidence, mortality, and disability-adjusted life years (DALYs) of CRC and explore potential changes in the temporal trends of the CRC burden in Shanghai during 2002 to 2016.

METHODS

The cancer statistics and demographics were obtained from the Cancer Registry and the Statistics Bureau of Pudong New Area, respectively. Data from 2002 to 2016 were included and analyzed retrospectively. DALYs were calculated using DisMod and the age-standardized rates (ASRs) were obtained according to Segi world standard population. Joinpoint regression was used to measure the trends in CRC incidence and to estimate the annual percent change.

RESULTS

The increasing trend of CRC ASR incidence halted after 2014, coinciding with the introduction of the Shanghai CRC screening program. The ASRs of mortality and DALYs increased, at 0.42% ( P  < 0.05) and 4.07% ( P  < 0.001) per year, respectively, which were mainly driven by men and individuals aged above the CRC screening program target.

CONCLUSIONS

The disease burden of CRC in Shanghai remains serious, especially among men, and individuals aged >74 years. The benefits of the screening program have been partially proven by the ASRs of CRC incidence, providing important insights into better and wider application of screening programs.

Statistical methods for measuring trends in colorectal cancer incidence in registries: A systematic review

Background

Monitoring cancer trends in a population is essential for tracking the disease’s burden, allocating resources, and informing public health policies. This review describes variations in commonly employed methods to estimate colorectal cancer (CRC) incidence trends.

Methods

We performed a systematic literature search in four databases to identify population-based studies reporting CRC incidence trends, published between January 2010 and May 2020. We extracted and described data on methods to estimate trends and assess model validity, and the software used.

Results

This review included 145 articles based on studies conducted in five continents. The majority (93%) presented visual summaries of trends combined with absolute, relative, or annual change estimates. Fourteen (10%) articles exclusively calculated the relative change in incidence over a given time interval, presented as the percentage of change in rates. Joinpoint regression analysis was the most commonly used method for assessing incidence trends (n= 65, 45%), providing estimates of the annual percentage change (APC) in rates. Nineteen (13%) studies performed Poisson regression and 18 (12%) linear regression analysis. Age-period-cohort modeling- a type of generalized linear models- was conducted in 18 (12%) studies. Thirty-nine (37%) of the studies modeling incidence trends (n=104, 72%) indicated the method used to evaluate model fitness. The joinpoint program (52%) was the statistical software most commonly used.

Conclusion

This review identified variation in the calculation of CRC incidence trends and inadequate reporting of model fit statistics. Our findings highlight the need for increasing clarity and transparency in reporting methods to facilitate interpretation, reproduction, and comparison with findings from previous studies.

Analysing 11 years of incidence trends, clinicopathological characteristics, and forecasts of colorectal cancer in young and old patients: a retrospective cross-sectional study in an Indonesian national referral hospital

OBJECTIVE

To obtain annual incidence trends, understand clinicopathological characteristics, and forecast the future burden of colorectal cancer (CRC) in Indonesia.

DESIGN

11-year retrospective cross-sectional study.

SETTING

A national referral hospital in Jakarta, Indonesia.

PARTICIPANTS

Data from 1584 eligible cases were recorded for trends and forecasting analyses; 433 samples were analysed to determine clinicopathological differences between young (<50 years) and old (≥50 years) patients.

METHODS

Trend analyses were done using Joinpoint software, expressed in annual percentage change (APC), and a regression analysis was executed to generate a forecasting model. Patients' characteristics were compared using χ2 or non-parametric tests.

MAIN OUTCOMES

Analysis of trends, forecasting model, and clinicopathological features between the age groups.

RESULTS

A significant increase in APC was observed among old patients (+2.38%) for CRC cases. Colon cancer increased remarkably (+9.24%) among young patients; rectal cancer trends were either stable or declining. The trend for right-sided CRC increased in the general population (+6.52%) and old patients (+6.57%), while the trend for left-sided CRC was stable. These cases are expected to be a significant health burden within the next 10 years. Patients had a mean age of 53.17±13.94, 38.1% were young, and the sex ratio was 1.21. Prominent characteristics were left-sided CRC, tumour size ≥5 cm, exophytic growth, adenocarcinoma, histologically low grade, pT3, pN0, inadequately dissected lymph nodes (LNs), LN ratio <0.05, no distant metastasis, early-stage cancer, no lymphovascular invasion, and no perineural invasion (PNI). Distinct features between young and old patients were found in the histological subtype, number of dissected LN, and PNI of the tumour.

CONCLUSIONS

Epidemiological trends and forecasting analyses of CRC cases in Indonesian patients showed an enormous increase in colon cancer in young patients, a particularly concerning trend. Additionally, young patients exhibited particular clinicopathological characteristics that contributed to disease severity.

Combined endoscopic robotic surgery for complex colonic polyp resection: case series

BACKGROUND

The study objective was to evaluate combined endoscopic and robotic surgery, a novel surgical technique modifying traditional combined endoscopic laparoscopic surgery through robotic assistance, and characterize a series of patients who underwent the modified operative technique.

METHODS

A retrospective case series was performed. The first thirty-seven consecutive patients who underwent combined endoscopic robotic surgery by a single colorectal surgeon from March 2018 to October 2019 were included. Main outcome measures included operative time, intra-operative complication, 30-day post-operative complication, and hospital length of stay.

RESULTS

Combined endoscopic and robotic surgery was performed in 37 cases, 32 (86.5%) of which saw the technique through to completion. Median operative room time was 73 min (range 31-184 min). No intraoperative complications occurred and 2 (6.3%) experienced 30-day post-operative complications. Median hospital length of stay was 1.1 days (range 0.2-2.0 days). Median polyp size was 35 mm (range 20-130 mm). Polyps were resected from the following locations: cecum (37.5%), ascending colon (28.1%), transverse colon (21.9%), descending colon (3.1%), sigmoid colon (6.3%), and rectum (3.1%). Pathology demonstrated 77.4% tubular adenoma, 12.9% sessile serrated adenoma, 6.5% dysplasia, and 3.2% signet cell adenocarcinoma.

CONCLUSION

Combined endoscopic robotic surgery was associated with decreased operative time, complication rates, and hospital length of stay compared to literature-reported statistics for combined endoscopic laparoscopic surgery. Increased confidence with 3-dimensional visualization and intracorporeal suturing using combined endoscopic and robotic surgery was noted. Additional studies are needed to further define the role of robotics in combined endoscopic surgery.

A systematic review of methods to estimate colorectal cancer incidence using population-based cancer registries

Background

Epidemiological studies of incidence play an essential role in quantifying disease burden, resource planning, and informing public health policies. A variety of measures for estimating cancer incidence have been used. Appropriate reporting of incidence calculations is essential to enable clear interpretation. This review uses colorectal cancer (CRC) as an exemplar to summarize and describe variation in commonly employed incidence measures and evaluate the quality of reporting incidence methods.

Methods

We searched four databases for CRC incidence studies published between January 2010 and May 2020. Two independent reviewers screened all titles and abstracts. Eligible studies were population-based cancer registry studies evaluating CRC incidence. We extracted data on study characteristics and author-defined criteria for assessing the quality of reporting incidence. We used descriptive statistics to summarize the information.

Results

This review retrieved 165 relevant articles. The age-standardized incidence rate (ASR) (80%) was the most commonly reported incidence measure, and the 2000 U.S. standard population the most commonly used reference population (39%). Slightly more than half (54%) of the studies reported CRC incidence stratified by anatomical site. The quality of reporting incidence methods was suboptimal. Of all included studies: 45 (27%) failed to report the classification system used to define CRC; 63 (38%) did not report CRC codes; and only 20 (12%) documented excluding certain CRC cases from the numerator. Concerning the denominator estimation: 61% of studies failed to state the source of population data; 24 (15%) indicated census years; 10 (6%) reported the method used to estimate yearly population counts; and only 5 (3%) explicitly explained the population size estimation procedure to calculate the overall average incidence rate. Thirty-three (20%) studies reported the confidence interval for incidence, and only 7 (4%) documented methods for dealing with missing data.

Conclusion

This review identified variations in incidence calculation and inadequate reporting of methods. We outlined recommendations to optimize incidence estimation and reporting practices. There is a need to establish clear guidelines for incidence reporting to facilitate assessment of the validity and interpretation of reported incidence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01632-7.

Association of Blastocystis hominis with colorectal cancer: A systematic review of in vitro and in vivo evidences

BACKGROUND

Recently, there have been several findings that showed intestinal colonisation of Blastocystis hominis (Blastocystis) as a risk factor to the worsening of colorectal cancer (CRC). However, studies have shown controversial results in the pathogenicity of Blastocystis.

AIM

To review systematically the evidence available on the association between CRC and Blastocystis and the prevalence of Blastocystis in CRC patients and to investigate cytopathic and immunological effects of Blastocystis in in vitro and in vivo studies.

METHODS

PRISMA guidelines were utilised in conducting this systematic review. Original articles published before February 2, 2020 were included. PubMed, Science Direct, Scopus and Google scholar databases were searched. Manual searching was carried out to find articles missed during the online search.

RESULTS

Out of 12 studies selected for this systematic review, seven studies confirmed the prevalence of Blastocystis and found it to be between 2%-28% in CRC patients, whereby subtype 1 and subtype 3 were predominantly seen. A total of four studies employing in vitro human colorectal carcinoma cell line study models showed significant cytopathic and immunological effects of Blastocystis. In addition, one in vivo experimental animal model study showed that there was a significant effect of infection with Blastocystis on exacerbation of colorectal carcinogenesis.

CONCLUSION

Blastocystis is a commonly identified microorganism in CRC patients. These studies have provided supportive data that Blastocystis could exacerbate existing CRC via alteration in host immune response and increased oxidative damage. Future studies of CRC and Blastocystis should attempt to determine the various stages of CRC that are most likely to be associated with Blastocystis and its relationship with other intestinal bacteria.

circRNA_101277 Influences Cisplatin Resistance of Colorectal Cancer Cells by Modulating the miR-370/IL-6 Axis

Background

Colorectal cancer (CRC) is among the most prevalent malignancies globally. Early detection of precancerous lesions through routine colonoscopy has led to a dramatic reduction in CRC-related incidence and mortality among those between the ages of 50 and 70. However, in those where the disease progresses to an advanced stage, chemotherapy remains the primary available treatment option, and the associated 5-year survival rate remains low. The identification of genes associated with CRC chemoresistance would thus be a beneficial approach to identifying novel treatments for this deadly disease.

Methods

The expression of circRNA_101277, miR-370, and IL-6 was assessed via qRT-PCR. IL-6 levels were measured with a human IL-6 ELISA kit based on the provided protocols. CRC cellular proliferation and cisplatin IC50 values were quantified via MTT assays. Luciferase assays were used to detect circRNA_101277 and miR-370 binding sites or miR-370 and IL-6 binding sites.

Results

circRNA_101277 was increased in CRC tissues compared with control samples. circRNA_101277 overexpression was evident in CRC cells, and knockdown of this circRNA suppressed cellular proliferation and cisplatin resistance in these cancer cells. At a mechanistic level, circRNA_101277 was found to function by sequestering miR-370, thereby upregulating the miR-370 target gene IL-6 and promoting cisplatin resistance via this miR-370/IL-6 axis.

Conclusion

In summary, our data highlight circRNA_101277 as a novel driver of CRC cell cisplatin resistance that functions by sequestering miR-370 and thereby enhancing IL-6 expression. These findings suggest that this circRNA_101277/miR-370/IL-6 axis may represent a critical axis of chemoresistance in CRC that can be targeted to diagnose and/or treat this cancer.

ERp29 forms a feedback regulation loop with microRNA-135a-5p and promotes progression of colorectal cancer

Expression of endoplasmic reticulum (ER) stress-associated genes is often dysregulated in cancer progression. ER protein 29 (ERp29) is abnormally expressed in many neoplasms and plays an important role in tumorigenesis. Here, we showed ERp29 is a novel target for microRNA-135a-5p (miR-135a-5p) to inhibit the progression of colorectal cancer (CRC); correspondingly, ERp29 acts as an oncoprotein in CRC by promoting proliferation and metastasis of CRC cells, and suppressing apoptosis of the cells. More importantly, we found that miR-135a-5p expression is reversely upregulated by ERp29 through suppressing IL-1β-elicited methylation of miR-135a-5p promoter region, a process for enterocyte to maintain a balance between miR-135a-5p and ERp29 but dysregulated in CRC. Our study reveals a novel feedback regulation loop between miR-135a-5p and ERp29 that is critical for maintaining appropriate level of each of them, but partially imbalanced in CRC, resulting in abnormal expression of miR-135a-5p and ERp29, which further accelerates CRC progression. We provide supporting evidence for ERp29 and miR-135a-5p as potential biomarkers for diagnosis and treatment of CRC.

Penicillin disrupts mitochondrial function and induces autophagy in colorectal cancer cell lines

Colorectal cancer is a common malignant tumor of the gastrointestinal tract. Currently, the main treatment is surgical resection, which can be combined with other treatments. However, treatment efficacy is poor, and colorectal cancer is prone to relapse and metastasis; thus, identifying an effective anti-cancer drug is an urgent requirement. The present study examined the antagonistic effect of penicillin on cultured colorectal cancer cells and the related mechanism. A MTT assay was used to assess the growth of the colorectal cancer cells treated with penicillin and to determine the optimal drug concentration. The wound healing and Transwell invasion assays were performed to investigate the effect of penicillin on the migration and invasion of the colorectal cancer cells. Live cell mitochondrial energy metabolism analysis was performed to detect changes in mitochondrial energy metabolism of the colorectal cancer cells, while western blot analysis was used to measure the expression of cytochrome c and autophagy-related protein, LC3. RFP-GFP-LC3 lentivirus was used to detect autophagic flux, and autophagosomes were observed using a transmission electron microscope, while flow cytometry was used to analyze the effect of penicillin on cell cycle progression and apoptosis of the colorectal cancer cells. After penicillin treatment, the growth, migration and invasion ability of the colorectal cancer cells were inhibited. The mitochondrial energy metabolism of the cell was impaired, and the basic respiratory capacity, maximum respiratory capacity, respiratory potential, and ATP production were all reduced. The protein expression levels of the autophagy-related proteins, LC3-II/LC3-I increased in a dose- and time-dependent manner. In addition, autophagy flux and the number of autophagosomes increased, and mitochondrial structural damage was observed. The cell cycle was arrested at the G₁ phase, the number of early apoptotic cells increased and the protein expression level of cleaved caspase-3 increased, while penicillin-induced apoptosis was blocked by the autophagy inhibitor 3-MA. In conclusion, penicillin disrupted mitochondrial function and energy metabolism in the colorectal cancer cells, which resulted in the induction of autophagic apoptosis and ultimately the inhibition of cancer cell growth and metastasis.

Younger age at onset of colorectal cancer is associated with increased patient's delay

AIM

This study aimed to investigate if younger age at diagnosis of colorectal cancer was associated with a diagnostic delay. The secondary objective was to evaluate if symptomatology varied with age.

METHOD

The study population consisted of the cohorts from two prospective multicentre studies conducted in Sweden and Denmark, the QoLiRECT and QoLiCOL studies. These studies investigated the quality of life in patients with colorectal cancer. Participants responded to the validated questionnaires used to extract information on patient's and doctor's delay as well as first presenting symptoms. Clinical variables were retrieved from the Swedish Colorectal Cancer Registry and the Danish Colorectal Cancer Group Database.

RESULTS

2574 patients were included, 1085 from QoLiRECT and 1489 from QoLiCOL. The probability of an increased patient's delay was higher when age decreased by 10 years (the SD in both QoLiRECT and QoLiCOL), adjusted OR 1.19 (95%CI: 1.10; 1.30), p < 0.001. A similar effect was found for doctor's delay, but the age effect was smaller in this case, adjusted OR 1.05 (95%CI: 0.97; 1.15), p = 0.177. When the age effect was analysed non-linearly, an increased probability of a delay was seen for patients from around 60 years and below. Younger patients were equally or more likely to report the symptoms of blood in stool, diarrhoea, constipation, mucus in faeces, faecal urgency, faecal emptying difficulties and pain compared to older patients.

CONCLUSION

Younger patients were more likely to have an increased patient's delay, probably contributing to a delayed diagnosis of colorectal cancer. Symptomatology at diagnosis was similar irrespective of age.

Effects of Adjuvant Therapy Compliance and Anastomotic Leakage on the Oncologic Outcomes of Patients With Rectal Cancer After Curative Resection

BACKGROUND

Anastomotic leakage might be directly or indirectly related to the prognosis of patients with rectal cancer.

OBJECTIVE

This study aimed to investigate whether anastomotic leakage affects the oncologic outcomes in patients with rectal cancer.

DESIGN

This was a retrospective analysis of prospectively collected data.

SETTINGS

This study was conducted at a teaching hospital between January 2009 and December 2013.

PATIENTS

Patients who underwent curative resection for primary rectal cancer were included.

MAIN OUTCOME AND MEASURE

Kaplan-Meier analyses were used to evaluate disease-free survival and overall survival.

RESULTS

The overall incidence of anastomotic leakage was 2.7% (107/3865). Local recurrence was more frequent in patients with anastomotic leakage than in those without (14.0% vs 6.7%; p = 0.007). By multivariate analysis, anastomotic leakage was associated with increased local recurrence rate (p = 0.014) and poorer overall survival (p = 0.011). In subgroup analysis, compared with other pathologic risk factors, anastomotic leakage was associated with higher occurrence of local and distant recurrence in patients with stage II rectal cancer (p = 0.031 and <0.001). In patients with stage III rectal cancers, adjuvant therapy was more likely to be delayed or canceled in those experiencing anastomotic leakage (63 vs 39 d, p < 0.001; 37.3% vs 66.7%, p < 0.001). In addition, this patient group had the worst survival outcome when compared with those without anastomotic leakage and those with timely adjuvant therapy (5-year disease-free survival rate, p = 0.013; 5-year overall survival rate, p = 0.001).

LIMITATIONS

This study is limited by its retrospective nature.

CONCLUSIONS

There was a robust association between anastomotic leakage and local recurrence, while also potentially affect long-term survival of the patient group. Delayed or cancelled adjuvant therapy administration because of anastomotic leakage may partly account for the poorer survival in those patients with advanced rectal cancer. See Video Abstract at http://links.lww.com/DCR/B459.

EFECTOS DE OBSERVANCIA DE TERAPIA ADYUVANTE Y FUGA ANASTOMTICA, EN RESULTADOS ONCOLGICOS DE PACIENTES CON CNCER RECTAL, DESPUS DE UNA RESECCIN CURATIVA

ANTECEDENTES:La fuga anastomótica podría estar relacionada directa o indirectamente, con el pronóstico de los pacientes con cáncer de recto.OBJETIVO:El estudio tuvo como objetivo investigar si la fuga anastomótica afecta los resultados oncológicos, en pacientes con cáncer de recto.DISEÑO:Fue un análisis retrospectivo de datos recolectados prospectivamente.AJUSTE:El estudio se realizó en un hospital universitario entre enero de 2009 y diciembre de 2013.PACIENTES:Pacientes sometidos a resección curativa por cáncer rectal primario.PRINCIPALES MEDIDAS DE RESULTADO:Se utilizaron análisis de Kaplan-Meier para evaluar la supervivencia libre de enfermedad y supervivencia general.RESULTADOS:La incidencia global de fuga anastomótica fue del 2,7% (107/3865). La recurrencia local fue más frecuente en pacientes con fuga anastomótica, que en aquellos sin ella (14,0% frente a 6,7%, p = 0,007). Por análisis multivariado, la fuga anastomótica se asoció con una mayor tasa de recurrencia local (p = 0,014) y una peor supervivencia general (p = 0,011). En el análisis de subgrupos, en comparación con otros factores de riesgo patológicos, la fuga anastomótica se asoció con una mayor incidencia de recidiva local y a distancia en pacientes con cáncer rectal en estadio II (p = 0,031 y <0,001, respectivamente). En pacientes con cáncer rectal estadio III, la terapia adyuvante tuvo más probabilidades de retrasarse o cancelarse en aquellos que sufrían fuga anastomótica (63 vs 39 días, p <0,001; 37,3% vs 66,7%, p <0,001). Y este grupo de pacientes tuvo el peor resultado de supervivencia en comparación con aquellos sin fuga anastomótica y aquellos con terapia adyuvante oportuna (tasa de supervivencia libre de enfermedad a 5 años, p = 0,013; tasa de supervivencia global a 5 años, p = 0,001).LIMITACIONES:El estudio está limitado por su naturaleza retrospectiva.CONCLUSIONES:Hubo una sólida asociación entre la fuga anastomótica y la recurrencia local, mientras que también afecta potencialmente la supervivencia a largo plazo, del grupo de pacientes. La administración de terapia adyuvante retrasada o cancelada debido a una fuga anastomótica, puede explicar en parte, la menor supervivencia en aquellos pacientes con cáncer rectal avanzado. Consulte Video Resumen en http://links.lww.com/DCR/B459.

Effects of Screening Compliance on Long-term Reductions in All-Cause and Colorectal Cancer Mortality

BACKGROUND & AIMS

Randomized trials have shown that biennial fecal occult blood test (FOBT) screening reduces mortality from colorectal cancer (CRC), but not overall mortality. Differences in benefit for men vs women, and by age, are unknown. We sought to evaluate long-term reduction in all-cause and CRC-specific mortality in men and women who comply with offered screening, and in different age groups, using individual participant data from 2 large randomized trials of biennial FOBT screening, compared with an intention to treat analysis.

METHODS

We updated the CRC and all-cause mortality from the Danish CRC screening trial (n = 61,933) through 30 years of follow up and pooled individual participant data with individual 30-year follow-up data from the Minnesota Colon Cancer Control trial (n = 46,551). We compared the biennial screening groups to usual care (controls) in individuals 50-80 years old using Kaplan Meier estimates of relative risks and risk differences, adjusted for study differences in age, sex, and compliance.

RESULTS

Through 30 years of follow up, there were 33,478 (71.9%) and 33,479 (72.2%) total deaths and 1023 (2.2%) and 1146 (2.5%) CRC deaths in the biennial screening (n = 46,553) and control groups (n = 46,358), respectively. Among compliers, biennial FOBT screening significantly reduced CRC mortality by 16% (relative risk [RR], 0.84; 95% CI, 0.74-0.96) and all-cause mortality by 2% (RR, 0.98; 95% CI, 0.97-0.99). Among compliers, the reduction in CRC mortality was larger for men (RR, 0.75; 95% CI, 0.62-0.90) than women (RR, 0.91; 95% CI, 0.75-1.09). The largest reduction in CRC mortality was in compliant men 60-69 years old (RR, 0.59; 95% CI, 0.42-0.81) and women 70 years and older (RR, 0.53; 95% CI, 0.30-0.94).

CONCLUSIONS

Long-term CRC mortality outcomes of screening among compliers using biennial FOBT are sustained, with a statistically significant reduction in all-cause mortality. The reduction in CRC mortality is greater in men than women-the benefit in women lags that of men by about 10 years.

Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries

This article provides an update on the global cancer burden using the GLOBOCAN 2020 estimates of cancer incidence and mortality produced by the International Agency for Research on Cancer. Worldwide, an estimated 19.3 million new cancer cases (18.1 million excluding nonmelanoma skin cancer) and almost 10.0 million cancer deaths (9.9 million excluding nonmelanoma skin cancer) occurred in 2020. Female breast cancer has surpassed lung cancer as the most commonly diagnosed cancer, with an estimated 2.3 million new cases (11.7%), followed by lung (11.4%), colorectal (10.0 %), prostate (7.3%), and stomach (5.6%) cancers. Lung cancer remained the leading cause of cancer death, with an estimated 1.8 million deaths (18%), followed by colorectal (9.4%), liver (8.3%), stomach (7.7%), and female breast (6.9%) cancers. Overall incidence was from 2-fold to 3-fold higher in transitioned versus transitioning countries for both sexes, whereas mortality varied <2-fold for men and little for women. Death rates for female breast and cervical cancers, however, were considerably higher in transitioning versus transitioned countries (15.0 vs 12.8 per 100,000 and 12.4 vs 5.2 per 100,000, respectively). The global cancer burden is expected to be 28.4 million cases in 2040, a 47% rise from 2020, with a larger increase in transitioning (64% to 95%) versus transitioned (32% to 56%) countries due to demographic changes, although this may be further exacerbated by increasing risk factors associated with globalization and a growing economy. Efforts to build a sustainable infrastructure for the dissemination of cancer prevention measures and provision of cancer care in transitioning countries is critical for global cancer control.

Feasibility of Methylated CLIP4 in Stool for Early Detection of Colorectal Cancer: A Training Study in Chinese Population

BACKGROUND

Early detection of colorectal cancer (CRC) and precancerous lesion is vitally important for mitigating CRC morbidity and mortality. Aberrant DNA methylations in certain promoter regions have been identified to be closely associated with CRC development and progression, suggesting their potential as diagnostic biomarkers for early detection. In this study, we evaluated the performance of methylated CLIP4 in stool specimens as a potential biomarker for CRC detection.

METHODS

A total of 321 subjects out of 365 enrolled participants were included in the final analysis, including 154 CRC patients, 23 advanced adenoma (AA) patients, 49 small polyp (SP) patients, and 95 healthy controls. CLIP4 methylation level was examined by qPCR with bisulfite converted DNA purified from approximately 5 g stool specimen.

RESULTS

Methylated CLIP4 test showed high sensitivities of 78.3% (95% CI: 55.8%-91.7%) and 90.3% (95% CI: 84.2%-94.3%) for detecting AA and CRC, respectively, with a specificity of 88.4% (95% CI: 79.8%-93.8%). CLIP4 methylation level discriminated AA and CRC patients from control subjects with area under the curve values of 0.892 (95% CI: 0.795-0.988) and 0.961 (95% CI: 0.938-0.983). Further analysis indicated no significant difference in sensitivities among different ages, genders, stages, locations, sides, tumor sizes and differentiation statuses.

CONCLUSIONS

Methylated CLIP4 showed a strong potential as a noninvasive biomarker for early CRC detection.

Colorectal cancer epidemiology and clinical study in Misan

Introduction Colorectal carcinoma is commonest cancer of gastrointestinal tract. It is represent third cancer in man worldwide beyond lung and prostate cancers. It is fourth cancer in woman beyond breast, lung and uterus cancers. Deaths from colorectal cancer are more in compare with other GIT cancers.

Objective The aim is prove epidemiological and clinical data of colorectal cancer.

Method Our study conducted in Misan Province, Iraq. The data collected from 2013 to 2016. Seventy one patients that found have colorectal cancer. Gender, age, residency, site of cancer, family history, past history, year of onset, smoking history, alcohol intake, presentation, staging and histopathology pattern are get.

Results Prevalence of colon and rectum carcinoma is 3.75%. The most age group affected was 51–60 years as 30.99%. The gender and residency of patients have no effect on cancer percent. Obesity, Family history, cigarette smoking and alcohol consumption risk factors. In 42.25% of patients had family history of cancer.

Conclusion Most common site of colorectal carcinoma left colon, which present in 61.97%. There is increase in new cases detection of colorectal carcinoma from 2013 to 2016. Advanced stages cancer were most common stages description as IIIA, IIIB, IIIC and IV in 12.67%, 16.90%, 19.72% and 15.49%. The common histopathological pattern is differentiated adenocarcinoma as 53.52%.

Ileocecal Valve Sparing Resection for the Treatment of Benign Cecal Polyps Unsuitable for Polypectomy

Background:

Not all benign-appearance polyps are amenable to endoscopic removal and colectomy is required in some cases. This study aims to compare the early outcomes of cecal wedge resection with ileocecal valve sparring versus standard right colectomy in patients with endoscopically unresectable cecal polyps referred for surgery.

Methods:

From Apr 2010 to Aug 2019, all consecutive patients who underwent cecal wedge resection or right colectomy in ten European centers for a presumed endoscopically benign polyp unsuitable for endoscopic resection were retrospectively analyzed. The primary endpoint was morbidity. Secondary endpoints were operative time and length of hospital stay.

Results:

One hundred and ten patients were included: 25 patients underwent cecal wedge resection and 85 a right colectomy. There were 56 men (51%) and 90% of the procedures were performed laparoscopically. 29 lesions were located at the appendix orifice (26.4%). Mortality was nil. There were no significant differences between both procedures for morbidity rate (20% versus 24.7%) or reoperation (4% versus 4.7%). Cecal wedge was related to shorter operative time (63 min versus 150 min, P = .008) and shorter hospital stay (5 days versus 6 days, P = .049). Only 1 patient had a salvage right colectomy after cecal wedge for a pTis adenoma.

Conclusions:

For benign-appearance cecal polyps unsuitable for endoscopic ablation, cecal wedge resection is safe and should be considered as an attractive alternative to right colectomy.

The prognostic impact of RAS on overall survival following liver resection in early versus late-onset colorectal cancer patients

BACKGROUND

The impact of molecular aberrations on survival after resection of colorectal liver metastases (CLM) in patients with early-age-onset (EOCRC) versus late-age-onset colorectal cancer (LOCRC) is unknown.

METHODS

Patients who underwent liver resection for CLM with known RAS, BRAF and MSI status were retrospectively studied. The prognostic impact of RAS mutations by age was analysed with age as a categorical variable and a continuous variable.

RESULTS

The study included 573 patients, 192 with EOCRC and 381 with LOCRC. The younger the age of onset of CRC, the greater the negative impact on overall survival of RAS mutations in the LOCRC, EOCRC, and ≤40 years (hazard ratio (HR), 1.64 (95% confidence interval (CI), 1.23-2.20), 2.03 (95% CI, 1.30-3.17), and 2.97 (95% CI, 1.44-6.14), respectively. Age-specific mortality risk and linear regression analysis also demonstrated that RAS mutations had a greater impact on survival in EOCRC than in LOCRC (slope: -4.07, 95% CI -8.10 to 0.04, P = 0.047, R² = 0.08).

CONCLUSION

Among patients undergoing CLM resection, RAS mutations have a greater negative influence on survival in patients with EOCRC, more so in patients ≤40 years, than in patients with LOCRC and should be considered as a prognostic factor in multidisciplinary treatment planning.

Risk Factors Associated With Early-Onset Colorectal Cancer

BACKGROUND & AIMS

The incidence of colorectal cancer (CRC) is increasing in individuals younger than 50 years, who do not usually undergo screening if they are of average risk. We sought to identify risk factors for CRC in this population.

METHODS

We compared sociodemographic and medical characteristics of patients who received a diagnosis of CRC at an age of 18-49 years (early-onset) with patients who received a diagnosis of CRC at an age of 50 years or older (late-onset) and with age-matched, cancer-free individuals (controls) at a tertiary academic hospital. We collected data from all adult patients with a diagnosis of CRC from January 1, 2011 through April 3, 2017 from electronic health records. Associations with risk factors were assessed using univariable and multivariable logistic regression models.

RESULTS

We identified 269 patients with early-onset CRC, 2802 with late-onset CRC, and 1122 controls. Compared with controls, patients with early-onset CRC were more likely to be male (odds ratio [OR], 1.87; 95% CI, 1.39-2.51), have inflammatory bowel disease (IBD) (3% vs 0.4% for controls; univariable P < .01), and have a family history of CRC (OR, 8.61; CI, 4.83-15.75). Prevalence values of well-established modifiable CRC risk factors, including obesity, smoking, and diabetes, were similar. Compared to patients with late-onset CRC, patients with early-onset CRC were more likely to be male (OR, 1.44; 95% CI, 1.11-1.87), black (OR, 1.73; 95% CI, 1.08-2.65) or Asian (OR, 2.60; 95% CI, 1.57-4.15), and have IBD (OR, 2.97; 95% CI, 1.16-6.63) or a family history of CRC (OR, 2.87; 95% CI, 1.89-4.25). Sensitivity analyses excluding IBD and family history of CRC showed comparable results. Early-onset CRC was more likely than late-onset disease to be detected in the left colon or rectum (75% vs 59%, P = .02) and at a late stage of tumor development (77% vs 62%, P = .01).

CONCLUSIONS

In a retrospective study of patients with early-onset CRC vs late-onset CRC or no cancer, we identified non-modifiable risk factors, including sex, race, IBD, and family history of CRC, to be associated with early-onset CRC.

Ginsenoside Rg3 enhances the anticancer effect of 5‑FU in colon cancer cells via the PI3K/AKT pathway

Chemotherapy is one of the most commonly used treatments for patients with advanced colon cancer, yet the toxicity of chemotherapy agents, such as 5‑fluorouracil (5‑FU), limits the effectiveness of chemotherapy. Ginsenoside Rg3 (Rg3) is an active ingredient isolated from ginseng. Rg3 has been shown to display anticancer effects on a variety of malignancies. Yet, whether Rg3 synergizes the effect of 5‑FU to inhibit the growth of human colon cancer remains unknown. The present study was designed to ascertain whether Rg3 is able to enhance the anti‑colon cancer effect of 5‑FU. The results revealed that combined treatment of Rg3 and 5‑FU significantly enhanced the inhibition of the proliferation, colony formation, invasion and migration of human colon cancer cells (SW620 and LOVO) in vitro. We also found that combined treatment of Rg3 and 5‑FU significantly enhanced the apoptosis of colon cancer cells by activating the Apaf1/caspase 9/caspase 3 pathway and arrested the cell cycle of the colon cancer cells in G0/G1 by promoting the expression of Cyclin D1, CDK2 and CDK4. In addition, the PI3K/AKT signaling pathway in colon cancer cells was suppressed by Rg3 and 5‑FU. In vivo, Rg3 synergized the effect of 5‑FU to inhibit the growth of human colon cancer xenografts in nude mice. Similarly, combined treatment of Rg3 and 5‑FU altered the expression of colon cancer protein in vivo and in vitro. Collectively, the present study demonstrated that ginsenoside Rg3 enhances the anticancer effect of 5‑FU in colon cancer cells via the PI3K/AKT pathway.

Demographics Predict Stage III/IV Colorectal Cancer in Individuals Under Age 50

GOALS

The goal of this study was to quantify the association between demographic factors and advanced colorectal cancer (CRC) in patients under age 50.

BACKGROUND

CRC incidence in the United States has declined in older individuals but increased in those under age 50 (early-onset). More than 60% of early-onset CRC patients present with advanced disease (stage III/IV), but predictors of stage in this population are poorly defined.

STUDY

We analyzed CRC cases diagnosed between age 20 and 49 in the United States Surveillance, Epidemiology, and End Results (SEER) 18 database during 2004 to 2015. Logistic regression models were fit to assess the impact of age, sex, race, ethnicity, marital status, and cancer site on the probability of advanced disease.

RESULTS

The analysis included 37,044 cases. On multivariable regression, age was inversely associated with advanced disease. Relative to 45 to 49-year-olds, 40 to 44-year-olds had 8% greater odds of having advanced CRC, and 20 to 24-year-olds had 53% greater odds. Asians, blacks, and Pacific Islanders had 10%, 12%, and 45% greater odds of advanced disease compared with whites. Compared with nonpartnered individuals, those with partners had 11% lower odds of advanced CRC. Both right-sided and left-sided colon cancer were more likely to be diagnosed at stage IV compared with rectal cancer.

CONCLUSIONS

Among individuals with early-onset CRC, younger age, Asian, black, or Pacific Islander race, and being nonpartnered were predictors of advanced disease at presentation. Colon cancer was more likely to be diagnosed at stage IV than rectal cancer. Patient characteristics associated with advanced CRC may indicate both differences in tumor biology and disparities in health care access.

Fecal microRNAs as Innovative Biomarkers of Intestinal Diseases and Effective Players in Host-Microbiome Interactions

Over the past decade, short non-coding microRNAs (miRNAs), including circulating and fecal miRNAs have emerged as important modulators of various cellular processes by regulating the expression of target genes. Recent studies revealed the role of miRNAs as powerful biomarkers in disease diagnosis and for the development of innovative therapeutic applications in several human conditions, including intestinal diseases. In this review, we explored the literature and summarized the role of identified dysregulated fecal miRNAs in intestinal diseases, with particular focus on colorectal cancer (CRC) and celiac disease (CD). The aim of this review is to highlight one fascinating aspect of fecal miRNA function related to gut microbiota shaping and bacterial metabolism influencing. The role of miRNAs as "messenger" molecules for inter kingdom communications will be analyzed to highlight their role in the complex host-bacteria interactions. Moreover, whether fecal miRNAs could open up new perspectives to develop novel suitable biomarkers for disease detection and innovative therapeutic approaches to restore microbiota balance will be discussed.

Aberrant DNA Methylation of SEPT9 and SDC2 in Stool Specimens as an Integrated Biomarker for Colorectal Cancer Early Detection

Colorectal cancer (CRC) has become the second leading cause of new cancer cases and the fifth of cancer deaths in China, and early detection is the most effective way to reduce the incidence and mortality of CRC. A number of methylated DNA biomarkers have been found to associate with CRC and precancerous lesions in stool samples, indicating stool methylated DNA biomarkers are potential tools for CRC early detection. In this study, approximately 5 g of stool specimen was collected from 230 subjects (124 in the training set and 106 in the validation set). Stool DNA was extracted and bisulfite-converted, followed by ColoDefense test, a multiplex qPCR assay, that simultaneously detects methylated SEPT9 (mSEPT9) and methylated SDC2 (mSDC2). Youden index was employed to determine the cut-off value of ColoDefense test for stool specimens. In the training set, the optimized cut-off value of stool ColoDefense test was: mSEPT9 analyzed with 3/3 algorithm and mean mSEPT9 Ct values of <38, or mSDC2 with 2/3 algorithm. Stool ColoDefense test achieved Youden indexes of 79.9 and 57.4% in detecting CRC and advanced adenomas (AA), respectively. Its sensitivities in the training set for AA and CRC were 66.7% (95% CI: 24.1-94.0%) and 89.1% (95% CI: 77.1-95.5%) with a 90.8% (95% CI: 80.3-96.2%) specificity, and AUC was 0.956 (95% CI: 0.924-0.988). In the validation set, its sensitivities for AA and CRC were 66.7% (95% CI: 24.1-94.0%) and 92.3% (95% CI: 78.0-98.0%) with a 93.2% (95% CI: 82.7-97.8%) specificity, and AUC was 0.977 (95% CI: 0.952-1.000). Positive detection rate of stool ColoDefense test has been found to be independent of age, gender, tumor location, and tumor size. In conclusion, stool ColoDefense test demonstrated high sensitivities and specificity for the detection of AA and CRC. Therefore, it has the potential to become a low-cost, convenient, and highly effective tool for CRC early detection.

Afterthoughts on colonoscopy. Was it that bad?

OBJECTIVES

Colorectal cancer is among the top three most common cancers globally. In order to reduce the health burden, it is important to improve the uptake of colorectal cancer screening by understanding the barriers and facilitators encountered. There are numerous reports in the literature on the views of the general public on cancer screening. However, the experiences of colonoscopy patients are not as well studied. This paper maps their perceptions.

METHODS

Keyword searches for terms such as 'colorectal', 'colonoscopy' and 'qualitative' were conducted on 3 December 2019 in five databases: Medline, Embase, CINAHL, PsycINFO and Web of Science Core Collection. Qualitative articles that quoted colonoscopy-experienced patients with no prior history of colorectal cancer were included for the thematic analysis. The systematic review was then synthesized according to PRISMA guidelines.

RESULTS

The major themes were distilled into three categories: pre-procedure, during and post-procedure. The factors identified in the pre-procedure phase include the troublesome bowel preparation, poor quality of information provided and the dynamics within a support network. Perceptions of pain, emotional discomfort and the role of providers mark the experience during the procedure. The receipt of results, opportunities given for discussion and finances relating to colonoscopy are important post-procedure events.

CONCLUSION

Understanding colorectal cancer screening behaviour is fundamental for healthcare providers and authorities to develop system and personal level changes for the improvement of colorectal cancer screening services. The key areas include patient comfort, the use of clearer instructional aids and graphics, establishing good patient rapport, and the availability of individualized options for sedation and the procedure.

Evaluation of a Deep Neural Network for Automated Classification of Colorectal Polyps on Histopathologic Slides

IMPORTANCE

Histologic classification of colorectal polyps plays a critical role in screening for colorectal cancer and care of affected patients. An accurate and automated algorithm for the classification of colorectal polyps on digitized histopathologic slides could benefit practitioners and patients.

OBJECTIVE

To evaluate the performance and generalizability of a deep neural network for colorectal polyp classification on histopathologic slide images using a multi-institutional data set.

DESIGN, SETTING, AND PARTICIPANTS

This prognostic study used histopathologic slides collected from January 1, 2016, to June 31, 2016, from Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, with 326 slides used for training, 157 slides for an internal data set, and 25 for a validation set. For the external data set, 238 slides for 179 distinct patients were obtained from 24 institutions across 13 US states. Data analysis was performed from April 9 to November 23, 2019.

MAIN OUTCOMES AND MEASURES

Accuracy, sensitivity, and specificity of the model to classify 4 major colorectal polyp types: tubular adenoma, tubulovillous or villous adenoma, hyperplastic polyp, and sessile serrated adenoma. Performance was compared with that of local pathologists' at the point of care identified from corresponding pathology laboratories.

RESULTS

For the internal evaluation on the 157 slides with ground truth labels from 5 pathologists, the deep neural network had a mean accuracy of 93.5% (95% CI, 89.6%-97.4%) compared with local pathologists' accuracy of 91.4% (95% CI, 87.0%-95.8%). On the external test set of 238 slides with ground truth labels from 5 pathologists, the deep neural network achieved an accuracy of 87.0% (95% CI, 82.7%-91.3%), which was comparable with local pathologists' accuracy of 86.6% (95% CI, 82.3%-90.9%).

CONCLUSIONS AND RELEVANCE

The findings suggest that this model may assist pathologists by improving the diagnostic efficiency, reproducibility, and accuracy of colorectal cancer screenings.

Incidence, Clinico-demographic Profiles and Survival Rates of Colorectal Cancer in Northern Malaysia: Comparing Patients Above and Below 50 Years of Age

Background:

While the world witnesses an increasing trend of young-onset colorectal cancer (CRC), the information regarding the impact of age on CRC is limited in Malaysia. This study aimed to compare the incidence, clinic-demographic profiles and survival rates of CRC between patients above and under 50 years of age in northern Malaysia.

Methods:

This was a registry-based, cross-sectional study. All the CRC cases reported by 18 hospitals to the National Cancer Patient Registry - Colorectal Cancer (NCPR-CC) between January 2007 and December 2017 were included in the analysis. The patients were categorized by age into the above-50 and under-50 groups. The changes in the age-standardized incidence and mortality rates of both the age groups were determined using the time-series analysis, and the impact of age on the mortality risk was assessed using the Cox regression analysis.

Results:

Of the 6,172 CRC patients enrolled in the NCPR-CC, 893 (14.5%) were in the under-50 group. As compared with their older counterparts, the patients in the under-50 group were more likely to be female, be of Malay ethnicity, be non-smokers, have a family history of CRC, and present late for treatment. The age-standardized incidence and mortality rates of CRC in the under-50 group remained stable over the years, while a decreasing trend was clearly seen in the mortality rates of CRC in the above-50 group (p=0.003). Nevertheless, the two age groups also did not differ in the mortality risk (adjusted hazards ratio: 1.10; 95% CI: 0.90, 1.36).

Conclusion:

Young-onset CRC constituted a considerable proportion of CRC cases in Malaysia. However, in contrast with the findings of most studies, it demonstrated neither an uptrend in age-standardized incidence rates nor a higher mortality risk. Our findings suggest the need to upscale and lower the recommended age for CRC screening in Malaysia.

Multitarget Stool DNA Screening in Clinical Practice: High Positive Predictive Value for Colorectal Neoplasia Regardless of Exposure to Previous Colonoscopy

OBJECTIVES

Multitarget stool DNA (MT-sDNA) testing has grown as a noninvasive screening modality for colorectal cancer (CRC), but real-world clinical data are limited in the post-FDA approval setting. The effect of previous colonoscopy on MT-sDNA performance is not known. We aimed to evaluate findings of colorectal neoplasia (CRN) at diagnostic colonoscopy in patients with positive MT-sDNA testing, stratified by patient exposure to previous colonoscopy.

METHODS

We identified consecutive patients completing MT-sDNA testing over a 39-month period and reviewed the records of those with positive tests for neoplastic findings at diagnostic colonoscopy. MT-sDNA test positivity rate, adherence to diagnostic colonoscopy, and the positive predictive value (PPV) of MT-sDNA for any CRN and neoplastic subtypes were calculated.

RESULTS

Of 16,469 MT-sDNA tests completed, testing returned positive in 2,326 (14.1%) patients. After exclusion of patients at increased risk for CRC, 1,801 patients remained, 1,558 (87%) of whom underwent diagnostic colonoscopy; 918 of 1,558 (59%) of these patients had undergone previous colonoscopy, whereas 640 (41%) had not. Any CRN was found in 1,046 of 1,558 patients (PPV = 67%). More neoplastic lesions were found in patients without previous colonoscopy (73%); however, the rates remained high among those who had undergone previous colonoscopy (63%, P < 0.0001). The large majority (79%) of patients had right-sided neoplasia.

DISCUSSION

MT-sDNA has a high PPV for any CRN regardless of exposure to previous colonoscopy. Right-sided CRN was found at colonoscopy in most patients with positive MT-sDNA testing, representing a potential advantage over other currently available screening modalities for CRC.

Projected Reductions in Absolute Cancer-Related Deaths from Diagnosing Cancers Before Metastasis, 2006-2015

BACKGROUND

New technologies are being developed for early detection of multiple types of cancer simultaneously. To quantify the potential benefit, we estimated reductions in absolute cancer-related deaths that could occur if cancers diagnosed after metastasis (stage IV) were instead diagnosed at earlier stages.

METHODS

We obtained stage-specific incidence and survival data from the Surveillance, Epidemiology, and End Results Program for 17 cancer types for all persons diagnosed ages 50 to 79 years in 18 geographic regions between 2006 and 2015. For a hypothetical cohort of 100,000 persons, we estimated cancer-related deaths under assumptions that cancers diagnosed at stage IV were diagnosed at earlier stages.

RESULTS

Stage IV cancers represented 18% of all estimated diagnoses but 48% of all estimated cancer-related deaths within 5 years. Assuming all stage IV cancers were diagnosed at stage III, 51 fewer cancer-related deaths would be expected per 100,000, a reduction of 15% of all cancer-related deaths. Assuming one third of metastatic cancers were diagnosed at stage III, one third diagnosed at stage II, and one third diagnosed at stage I, 81 fewer cancer-related deaths would be expected per 100,000, a reduction of 24% of all cancer-related deaths, corresponding to a reduction in all-cause mortality comparable in magnitude to eliminating deaths due to cerebrovascular disease.

CONCLUSIONS

Detection of multiple cancer types earlier than stage IV could reduce at least 15% of cancer-related deaths within 5 years, affecting not only cancer-specific but all-cause mortality.

IMPACT

Detecting cancer before stage IV, including modest shifts to stage III, could offer substantial population benefit.

Impact of a real-time automatic quality control system on colorectal polyp and adenoma detection: a prospective randomized controlled study (with videos)

BACKGROUND AND AIMS

Quality control can decrease variations in the performance of colonoscopists and improve the effectiveness of colonoscopy to prevent colorectal cancers. Unfortunately, routine quality control is difficult to carry out because a practical method is lacking. The aim of this study was to develop an automatic quality control system (AQCS) and assess whether it could improve polyp and adenoma detection in clinical practice.

METHODS

First, we developed AQCS based on deep convolutional neural network models for timing of the withdrawal phase, supervising withdrawal stability, evaluating bowel preparation, and detecting colorectal polyps. Next, consecutive patients were prospectively randomized to undergo routine colonoscopies with or without the assistance of AQCS. The primary outcome of the study was the adenoma detection rate (ADR) in the AQCS and control groups.

RESULTS

A total of 659 patients were enrolled and randomized. A total of 308 and 315 patients were analyzed in the AQCS and control groups, respectively. AQCS significantly increased the ADR (0.289 vs 0.165, P < .001) and the mean number of adenomas per procedure (0.367 vs 0.178, P < .001) compared with the control group. A significant increase was also observed in the polyp detection rate (0.383 vs 0.254, P = .001) and the mean number of polyps detected per procedure (0.575 vs 0.305, P < .001). In addition, the withdrawal time (7.03 minutes vs 5.68 minutes, P < .001) and adequate bowel preparation rate (87.34% vs 80.63%, P = .023) were superior for the AQCS group.

CONCLUSIONS

AQCS could effectively improve the performance of colonoscopists during the withdrawal phase and significantly increase polyp and adenoma detection. (Clinical trial registration number: NCT03622281.).

A novel plasma based early colorectal cancer screening assay base on methylated SDC2 and SFRP2

BACKGROUND

Methylated SFRP2 was previously reported as a non-invasive biomarker for colorectal cancer (CRC) detection with a relatively low sensitivity for early stage CRC. The purpose of this study was to evaluate the performance of a new plasma based CRC screening assay, SpecColon test, which tested methylated SFRP2 and SDC2 simultaneously in a single qPCR reaction, in detecting CRC and advanced adenomas (AA).

METHOD

One milliliter plasma of 122 CRC patients, 12 AA patients, 93 patients with benign polyps, and 91 normal individuals were collected from the Affiliated Hospital of Xuzhou Medical University, and all samples were examined by SpecColon test.

RESULTS

The sensitivities for detecting AA and CRC by methylated SFRP2 alone were 50.0% (95% CI: 22.2-77.7%) and 63.1% (95% CI: 53.9-71.5%) with a specificity of 90.1% (95% CI: 81.6-95.1%). The sensitivities by methylated SDC2 alone were 33.3% (95% CI: 11.3-64.6%) and 56.6% (95% CI: 47.3-65.4%) with a specificity of 95.6% (95% CI: 88.5-98.6%). However, when methylated SFRP2 and methylated SDC2 were combined, the sensitivities for AA and CRC detection improved to 58.3% (95% CI: 28.6-83.5%) and 76.2% (95% CI: 67.5-83.3%) with a specificity of 87.9% (95% CI: 79.0-93.5%). The positive detection rates of benign polyp group and normal control group showed no significant difference (p > 0.01), whereas AA and CRC groups had significantly higher positive detection rates than normal individual group (p < 0.001).

CONCLUSION

The sensitivities for AA and early stage CRC by combined test of methylated SFRP2 and methylated SDC2, the so called SpecColon test, improved upon those by either biomarker alone without significant impact on the specificity. It has the potential to become a powerful, convenient and highly effective screening tool for early CRC screening.

LINC01413/hnRNP-K/ZEB1 Axis Accelerates Cell Proliferation and EMT in Colorectal Cancer via Inducing YAP1/TAZ1 Translocation

Long non-coding RNAs (lncRNAs) are crucial molecules in tumorigenesis and tumor growth in various human cancers, including colorectal cancer (CRC). Studies have revealed that lncRNAs can regulate cellular processes in cancers by interacting with proteins, for example RNA-binding proteins (RBPs). In this study, we recognize a novel lncRNA called LINC01413 that is upregulated in CRC tissues through lncRNAs microarray. Subsequently, we confirmed that an elevated level of LINC01413 expression in CRC tissues was strongly correlated to clinicopathological features, such as tumor size, tumor stage, lymph node metastasis, and distant metastasis, and its association with poor overall survival was also revealed. Additionally, LINC01413 facilitates cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in vitro. Also, silenced LINC01413 restrains tumor growth in vivo. Moreover, LINC01413 binds with hnRNP-K and induces YAP1 (yes-associated protein 1)/TAZ1 (tafazzin) nuclear translocation to regulate the expression of ZEB1 in CRC cells. Taken together, this research suggested LINC01413 as a positive regulator in CRC progression through the LINC01413/hnRNP-K/TAZ1/YAP1/ZEB1 axis, broadening a new view on CRC treatment.

Reevaluation of a rightward shift in colorectal cancer: A single-center retrospective study in Tianjin

OBJECTIVES

Some Western reports have shown a proximal shift in colorectal cancer (CRC), but there are few studies in China. This study aimed to provide more information for the management and screening of CRC by investigating trends in the anatomic distribution of CRC among the Chinese population in recent years.

METHODS

A retrospective study was conducted on patients with CRC admitted to the Digestive Endoscopy Center of Tianjin Medical University General Hospital between January 2000 and December 2017. Patients were divided into a left-sided colorectal cancer (LSCRC) group and a right-sided colon cancer (RSCC) group. The detection rates of LSCRC and RSCC based on patients' age and sex, and on the time periods were analyzed.

RESULTS

A total of 2319 cases were diagnosed with CRC among 75 183 consecutive patients. The prevalence of CRC showed a significant reduction from 2000-2008 to 2009-2017 (3.8% vs 2.7%, P < .001). The proportion of RSCC presented a downtrend from 2000-2008 to 2009-2017 (40.6% vs 37.7%, P > .05). There were slightly more RSCCs in female patients than in male patients, with no significant difference (40.9% vs 36.5%, P > .05). The proportion of RSCC in patients aged ≥50 years was similar to that in younger patients. The alarming symptoms between LSCRC and RSCC showed a significant difference (P < .05).

CONCLUSIONS

In the present study, the prevalence of CRC declined significantly with time. However, there did not appear to be a rightward shift in CRC among the patients in Tianjin over the past 18 years.

Prediction of risk scores for colorectal cancer patients from the concentration of proteins involved in mitochondrial apoptotic pathway

One of the major challenges in managing the treatment of colorectal cancer (CRC) patients is to predict risk scores or level of risk for CRC patients. In past, several biomarkers, based on concentration of proteins involved in type-2/intrinsic/mitochondrial apoptotic pathway, have been identified for prognosis of colorectal cancer patients. Recently, a prognostic tool DR_MOMP has been developed that can discriminate high and low risk CRC patients with reasonably high accuracy (Hazard Ratio, HR = 5.24 and p-value = 0.0031). This prognostic tool showed an accuracy of 59.7% when used to predict favorable/unfavorable survival outcomes. In this study, we developed knowledge based models for predicting risk scores of CRC patients. Models were trained and evaluated on 134 stage III CRC patients. Firstly, we developed multiple linear regression based models using different techniques and achieved a maximum HR value of 6.34 with p-value = 0.0032 for a model developed using LassoLars technique. Secondly, models were developed using a parameter optimization technique and achieved a maximum HR value of 38.13 with p-value 0.0006. We also predicted favorable/unfavorable survival outcomes and achieved maximum prediction accuracy value of 71.64%. A further enhancement in the performance was observed if clinical factors are added to this model. Addition of age as a variable to the model improved the HR to 40.11 with p-value as 0.0003 and also boosted the accuracy to 73.13%. The performance of our models were evaluated using five-fold cross-validation technique. For providing service to the community we also developed a web server ‘CRCRpred’, to predict risk scores of CRC patients, which is freely available at https://webs.iiitd.edu.in/raghava/crcrpred.

Near-Infrared Fluorescent Activated Polymeric Probe for Imaging Intraluminal Colorectal Cancer Tumors

Detection and removal of preneoplastic tumors is crucial for successful colorectal cancer (CRC) therapy. Here we describe the design of a Cathepsin B (CB)-activated polymeric probe, P-(GGFLGK-IR783), for imaging CRC tumors established by intrarectal or subcutaneous (s.c.) implantation of human colon cancer cells (SW-480 and HT-29) in mice. Multiple copies of the near-infrared fluorescent (NIRF) dye IR783 were attached to a single HPMA copolymer backbone via a CB-cleavable linker (GFLG), and the influence of the dye loading on the fluorescence quenching and activation by CB was assessed in vitro, ex vivo, and in vivo. The optimal dose and dosing regimen of P-(GGFLGK-IR783) for colonic tumor detection was determined. Increasing the IR783 loading in the copolymer from 2.5 to 20 mol % resulted in quenching of the fluorescence signal that was activated in vitro by the action of CB from different origins. Following intravenous administration, P-(GGFLGK-IR783)_7.5% preferentially accumulated in intrarectal and s.c. implanted tumors, allowing tumor visualization after 4 h and even 48 h postadministration. Activation of P-(GGFLGK-IR783)_7.5% by CB was clearly detected in s.c. implanted tumors, revealing about a 4-fold increase in the fluorescence signal in tumors vs healthy colon tissue. The probe containing the CB-cleavable linker produced higher fluorescence signal intensity in tumors, relative to the noncleavable probe. These results indicate that P-(GGFLGK-IR783)_7.5% may aid in detecting CRC tumors and can help to guide selective removal of polyps during colonoscopic procedures.

Colon cancer as a subsequent malignant neoplasm in young adults

BACKGROUND

The incidence of colon cancer (CC) is rising in younger adults and can occur de novo or in patients previously treated for another cancer. To the authors' knowledge, the impact on survival of CC occurring as a subsequent malignant neoplasm (SMN) has not been described for younger patients, which the authors anticipate to be lower with SMNs than that of primary CC.

METHODS

Patients aged <50 years with CC in the 2004 through 2014 National Cancer Data Base were identified. Patients were stratified by primary or subsequent occurrence. The impact of SMN status on overall survival (OS) was evaluated.

RESULTS

Of 41,915 patients, 2852 (6.8%) had colon SMNs. More patients with colon SMNs were aged 40 to 49 years compared with patients with primary CC (83% vs 77%; P < .001). Patients with colon SMNs presented with earlier clinical and pathological T, N, and M classifications (all P < .001). Colon SMNs more commonly occurred in the right colon, whereas primary CC was found to have a higher prevalence in the sigmoid colon (P < .001). Patients with colon SMNs more frequently underwent total colectomy (17% vs 5%; P < .001), but received less chemotherapy (53% vs 65%; P < .001). When adjusted for demographic, tumor, and treatment characteristics, SMN status was associated with a 23% decreased OS compared with primary CC (95% CI, 1.14-1.31; P < .001). Chemotherapy offered a 33% improvement in OS (95% CI, 0.56-0.8; P < .001).

CONCLUSIONS

Colon SMNs in younger patients present at an earlier stage and are treated more aggressively surgically compared with primary CCs. Patients with SMNs of the colon have decreased survival, although chemotherapy offers a survival advantage. Further investigation is warranted to determine whether these disparities are due to the effects of cancer treatment or differences in tumor biology.

Development and validation of a prognostic nomogram for early-onset colon cancer

The present study was to develop a prognostic nomogram to predict overall survival (OS) and cancer-specific survival (CSS) in early-onset colon cancer (COCA, age < 50). Patients diagnosed as COCA between 2004 and 2015 were retrieved from the surveillance, epidemiology, and end results (SEER) database. All included patients were assigned into training and validation sets. Univariate and multivariate analysis were used to identify independent prognostic variables for the construction of nomogram. The discrimination and calibration plots were used to measure the accuracy of the nomogram. A total of 11220 patients were included from the SEER database. The nomograms were established based on the variables significantly associated with OS and CSS using cox regression models. Calibration plots indicated that both nomograms in OS and CSS exhibited high correlation to actual observed results. The nomograms also displayed improved discrimination power than tumor-node-metastasis (TNM) stage and SEER stage both in the training and validation sets. The monograms established in the present study provided an alternative tool to both OS and CSS prognostic prediction compared with TNM and SEER stages.