Early Detection Of Colorectal Cancer Research Articles

Abstract 3353: Cell-free DNA (cfDNA) fragmentation profiles linked to copy number alteration analysis allows for early colorectal cancer detection

Abstract Background: Colorectal cancer (CRC) is the 3rd most diagnosed cancer worldwide. Early detection and correct patient stratification are important components for cancer prevention, diagnosis, and successful treatment. Cell-free DNA (cfDNA) fragment sizes have been previously shown to differ between cancer and non-cancer patients, while loss of heterozygosity is one of the major types of genetic inactivation, with long arm of chromosome 18 being most frequently reported to be deleted in CRC patients. We are here looking at the cfDNA fragmentation signal in early-stage CRC in the context of 18q21 region reported to exhibit copy number variations (CNV). Methods: This was a prospective, international multicenter observational cohort study. Plasma samples were collected either prior to a scheduled colonoscopy as part of standard colorectal cancer screening or prior to colonic surgery for primary CRC in several hospitals in Spain, Germany and Ukraine. Samples were prepared and analyzed with whole genome enzymatic sequencing approach in 2 separate sets (Training Set and Testing Set). Training set consisted of 24 CRC patients (3 stage 0, 10 stage I, 5 stage IIA, 3 stage III, 2 stage IIIA and 1 stage IIIB) and 24 matching controls. The proportion of aligned short fragments over the total number was computed for Chr18q21 based on pre-defined bins. From the total number of binned regions, those presenting an average correlation with the others >0.5 were discarded, getting a final set of regions, which were used as the input data of the Linear Discriminant Analysis (LDA) model. LDA model was then applied to independent Testing Set consisted of 12 CRC patients (4 stage I, 4 stage IIA and 4 stage III) and 12 matching controls. Results: Training Set analysis exhibited significant differences over whole Chr18q21 region, when comparing CRC and matching control patients. The 2959 region bins selected in the Training Set were used as the input data of the LDA model to test the performance. Model performance on an independent Testing set reached 83% sensitivity (10/12) at 92% specificity (11/12), with stage I sensitivity being as high as 75% (3/4) and stage IIA 100% (4/4). Sensitivity per cancer location was comparable with 83% sensitivity for proximal cancers (5/6) and 83% for distal cancers (5/6). Specificity was not affected by presence of benign findings such as hyperplastic polyps, diverticulosis/diverticulitis or hemorrhoids. Conclusions: The study results indicate that combining CNV information with the cfDNA fragment size information could serve as a promising new avenue for early detection of colorectal cancer, with early-stage (I-II) CRC sensitivity of 87.5% at 92% specificity. Larger cohort validation of these results is in progress. Citation Format: Pol Canal Noguer, Iva Cernosa, Fernando Trincado Alonso, Kristi Kruusmaa. Cell-free DNA (cfDNA) fragmentation profiles linked to copy number alteration analysis allows for early colorectal cancer detection [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3353.

Effects of Fecal Occult Blood Immunoassay Screening for Colorectal Cancer-Experience from a Hospital in Central Taiwan.

Background and Objectives: In 2004, the Health Administration of Taiwan began to promote a hospital-based cancer screening quality improvement program, under the principle that "prevention is better than therapy". The aim of this study was to evaluate the effectiveness of colorectal cancer (CRC) screening in patients who received a fecal immunochemical test (FIT) at a hospital in central Taiwan. Materials and Methods: This was a retrospective study. Results: Fecal occult blood immunoassays for CRC screening were conducted in 58,891 participants, of whom 6533 were positive (positive detection rate 11.10%). The positive patients then underwent colonoscopy, and the detection rates of polyps and CRC accounted for 53.6% and 2.4% of all colonoscopy-confirmed diagnoses (3607), respectively. We further enrolled data from patients diagnosed with CRC at our hospital from 2010 to 2018. The patients with CRC were divided into two groups according to whether or not they had received fecal occult blood screening. Among the 88 patients with CRC by screening, 54 had detailed medical records including cancer stage. Of these 54 patients, 1 (1.8%) had pre-stage, 11 (20.4%) had stage I, 24 (44.4%) had stage II, 10 (18.5%) had stage III, and 8 (14.8%) had stage IV CRC. The early cancer detection rates of the screening and non-screening groups were 66.7% and 52.7%, respectively, and the difference was significant (p = 0.00130). Conclusions: In this study, screening with FIT significantly increased the early detection of CRC. The main advantage of FIT is the non-invasiveness and low cost. It is hoped that the further adoption of early screening can increase the detection rates of colorectal polyps or early cancer to improve survival, reduce the high cost of subsequent cancer treatment, and reduce the burden on the patient and healthcare system.

Possible Value of Faecal Immunochemical Test (FIT) When Added in Symptomatic Patients Referred for Colonoscopy: A Systematic Review

We performed a systematic review search for CRC as an outcome of colonoscopy in referred symptomatic patients and separately for CRC as an outcome in symptomatic patients with a positive FIT. We searched systematically for clinical trials or observational studies in databases, followed by hand-searching of reference lists. We used random Meta-Disc to evaluate the diagnostic performance, using the exploration of heterogeneity with a variety of test statistics and by computing the pooled estimates. We included 35 studies, with almost 5 million symptomatic patients. In addition, we included nine prospective studies with a positive FIT in symptomatic patients, with more than 5000 patients. Significant heterogeneity was found for every symptom and the outcome of colonoscopy in the effect size of sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio. In a random effect model, the pooled sensitivity of colonoscopy in symptomatic patients was very low (25%). However, the pooled sensitivity in symptomatic patients with a positive FIT was 83% and the pooled specificity 77%. A total of 75 symptomatic patients (1.4%) had a false-negative FIT. Adding FIT in symptomatic patients seems useful for predicting CRC as an outcome of colonoscopy. FIT seems a potential tool for an improved triage of colonoscopy in symptomatic patients.

Detection of plasma miR-223 by a novel label-free graphene oxide/gold nanocomposite immunosensor in colorectal cancer patients: An electrochemical biosensor approach

MicroRNAs (miRNAs) are one group of the pertinent molecular biomarkers in the early detection of cancers, especially colorectal cancer. A simple and label-free nanostructured electrochemical biosensor was fabricated to detect miR-223, a colorectal cancer miRNA, by a vertical arrangement of graphene oxide (GO) decorated with gold (Au) Nano-flower nanostructures (GO@Au-NS). The use of high surface-to-volume aspect ratio nanostructures with excellent electroactivity that contain thiolated DNA probes (Cap-223) could increase the accessibility, chance, and recognition performance of miR-223. The substrate characteristics are scanned by HRSEM, EDX, and electrochemical techniques. Furthermore, the successful immobilization of Cap-223 on GO@Au-NS and their hybridization with targeted miR-223 macro-molecules were investigated by electrochemical techniques (CV, EIS, and DPV). The electroactivity of the working electrode before and after GO@Au-NS fabrication showed a significant difference. A wide range of linear detection of miR-223 by a fabricated biosensor was from zM to nM, with a lower detection limit (LOD) of 0.012 aM. The selectivity of the nanostructured miR-223 biosensor was also investigated by studying the discrimination ability of mismatched miRNAs sequences, which resulted in high selectivity for the biosensor. In addition, its efficiency in the detection of miR-223 in a real sample (human serum) showed a remarkable ability of the biosensor to detect it with a low percent of relative standard deviation (RSD = 5.7%). The developed electrochemical biosensor exhibited great potential for miRNA-based early detection of colorectal cancer and had excellent sensitivity, and selectivity, making it helpful for use in translational medicine research and clinical applications.

A three-plasma miRNA panel predicts the risk of colorectal cancer: a community-based nested case‒control study

Circulating microRNAs (miRNAs) have been considered potential markers for the early detection of malignant colorectal cancer (CRC). We aimed to identify a group of miRNAs for the early detection of CRC and assess their predictive ability in a community-based population in China. A nested case‒control study consisting of 97 incident colorectal cancer cases and 103 frequency-matched healthy controls was conducted. The data were randomly assigned into a training set (60%) and a test set (40%). We selected and detected 10 kinds of miRNAs in plasma samples. Multivariate logistic regression analysis was used to identify miRNAs associated with colorectal cancer risk in the training set and test set. Then, we evaluated the predictive ability of the identified miRNAs by the receiver operating characteristic curve (ROC). In this study, three miRNAs (miRNA-29a, miRNA-125b, miRNA-145) were significantly associated with colorectal cancer risk in both the training set and test set. The sensitivity of the identified miRNAs ranged from 0.854 to 0.961. After adding the identified miRNAs, the AUC (area under the curve) value significantly increased from 0.61 to 0.71 compared with the basic model consisting of only basic demographic information. We identified a three-plasma miRNA signature that may serve as a novel non-invasive biomarker in early CRC detection and in predicting individual CRC risk in the generation population.

What Is the Risk? Epidemiology and Evidence for Surveillance Regimens.

Patients with inflammatory bowel disease (IBD) have increased risk of colorectal cancer (CRC). The risk for CRC is positively correlated to the duration of disease, extent of colonic involvement, and severity of inflammation. After 8 to 10 years of IBD diagnosis, the risk for CRC rises substantially and screening colonoscopy is recommended. Surveillance colonoscopy interval ranges from 1 to 5 years depending on patient and disease-specific risk factors. IBD patients with high risk factors such as having concomitant primary sclerosing cholangitis, moderate-to-severe inflammation, first-degree relative with CRC at early age, or history of invisible dysplasia or high-risk visible dysplasia should undergo surveillance colonoscopy in 1 year. Meanwhile, those with minimal colonic involvement or ≥2 consecutive unremarkable examinations while in continuous remission may consider extending the surveillance interval to 5 years. Advance in colonoscopy technique such as chromoendoscopy using dyes and/or image digital processing (virtual chromoendoscopy) may enhance dysplasia detection and is the preferred method for IBD surveillance. In the era of high-definition colonoscope, the practice of obtaining extensive biopsies throughout the colon remains controversial but is generally recommended to improve the detection rate of invisible dysplasia. Endoscopic surveillance in IBD has been shown to result in earlier detection of CRC and improved prognosis.

Non-steroidal anti-inflammatory drugs and biomarkers: A new paradigm in colorectal cancer.

Colorectal cancer is a sporadic, hereditary, or familial based disease in its origin, caused due to diverse set of mutations in large intestinal epithelial cells. Colorectal cancer (CRC) is a common and deadly disease that accounts for the 4th worldwide highly variable malignancy. For the early detection of CRC, the most common predictive biomarker found endogenously are KRAS and ctDNA/cfDNA along with SEPT9 methylated DNA. Early detection and screening for CRC are necessary and multiple methods can be employed to screen and perform early diagnosis of CRC. Colonoscopy, an invasive method is most prevalent for diagnosing CRC or confirming the positive result as compared to other screening methods whereas several non-invasive techniques such as molecular analysis of breath, urine, blood, and stool can also be performed for early detection. Interestingly, widely used medicines known as non-steroidal anti-inflammatory drugs (NSAIDs) to reduce pain and inflammation have reported chemopreventive impact on gastrointestinal malignancies, especially CRC in several epidemiological and preclinical types of research. NSAID acts by inhibiting two cyclooxygenase enzymes, thereby preventing the synthesis of prostaglandins (PGs) and causing NSAID-induced apoptosis and growth inhibition in CRC cells. This review paper majorly focuses on the diversity of natural and synthetic biomarkers and various techniques for the early detection of CRC. An approach toward current advancement in CRC detection techniques and the role of NSAIDs in CRC chemoprevention has been explored systematically. Several prominent governing mechanisms of the anti-cancer effects of NSAIDs and their synergistic effect with statins for an effective chemopreventive measure have also been discussed in this review paper.

High expression of LY6E is an independent prognostic factor of colorectal cancer patients.

Colorectal cancer (CRC) is common cancer worldwide, and the 5‑year relative survival rate of CRC patients with distant metastasis is as low as 14%. Therefore, identifying markers of CRC is important for the early detection of CRC and applying appropriate treatment strategies. The lymphocyte antigen 6 family (LY6 family) is closely related to the behavior of various cancer types. Among the LY6 family, the lymphocyte antigen 6 complex, locus E (LY6E), which is specifically highly expressed in CRC. Hence, the effects of LY6E on cell function in CRC and its role in CRC recurrence and metastasis were investigated. Reverse transcription‑quantitative PCR, western blotting and invitro functional studies were carried out using four CRC cell lines. Immunohistochemical analysis of 110 CRC tissues was performed to explore the biological functions and expression patterns of LY6E in CRC. LY6E was overexpressed CRC tissues compared with that in adjacent normal tissues. High expression of LY6E in CRC tissues was an independent prognostic factor of worse overall survival (P=0.048). Knockdown of LY6E using small interfering RNA inhibited CRC cell proliferation, migration, invasion, and soft agar colony formation, indicating some of its effects on CRC carcinogenic functions. High expression of LY6E may have oncogenic functions in CRC and be useful as a valuable prognostic marker and potential therapeutic target for CRC.

Hydrogel Microneedles Extracting Exosomes for Early Detection of Colorectal Cancer.

There are several methods for early diagnosis of tumors, such as detecting circulating tumor DNAs, detecting circulating tumor cells, or imaging with tumor-targeting contrast agents. However, these assays are time-consuming and may cause patient discomfort during the biopsy collecting process. Here, we develop a facile method for early diagnosis of tumors by extracting exosomes from interstitial fluid (ISF) using hydrogel microneedles (MNs). The hydrogel MNs expand in the skin to absorb the ISF, and the tumor exosomes contained in the ISF bind with the glypican-1 antibodies inside the hydrogel of MNs. After removing the hydrogel on the MNs, exosomes are separately purified from the ISF to analyze tumor-related biomarkers. Finally, colorectal cancer can be diagnosed by ELISA for the colorectal cancer-induced model mice. This noninvasive hydrogel MN system to obtain the exosome samples would play an important role in early cancer diagnosis.

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

BackgroundEarly 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.MethodsWe 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.ResultsTwo 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.Conclusionscg13096260 and cg12993163 detection in stool samples could be a promising approach for screening and early diagnosis of CRC and precancerous lesions.

A multicenter, case-control study of a novel multi-target fecal DNA test for colorectal cancer detection.

26 Background: Globally, colorectal cancer (CRC) is the fourth most frequently occurring cancer and is the second leading cause of cancer-related deaths. Early detection and diagnosis of pre-cancer lesions and CRCs at curable stages could prevent the disease or improve patient survival. Colonoscopy, the current gold-standard approach for CRC screening, is an invasive procedure, and novel non-invasive alternatives are needed. Methods: In present study, we developed a novel multi-target fecal DNA based assay, which integrates detection of two stool DNA (sDNA) methylation markers by quantitative methylation-specific PCR (qMSP) and immunochemical fecal occult blood test. We performed a multi-center case-control study to validate the diagnostic performance of this novel multi-target assay. Thus far, we collected stool specimens from a total of 784 subjects including CRC, advanced adenoma, nonadvanced neoplasms and individuals with negative findings on colonoscopy from six sites across China. All participants underwent colonoscopy; the stool specimens were tested with the multi-target fecal DNA test as well as a quantitative FIT test (OC FIT-CHEK, Eiken) in parallel in order to perform head-to-head comparison of the test performance of both assays. Results: The multi-target fecal DNA test demonstrated a higher sensitivity (96.1%) than FIT (85.3%) for CRCs (n=204). Meanwhile, 20 of 39 (51.3%) patients with advanced adenoma tested positive by the fecal DNA test, which was remarkably superior to FIT (7 of 39 tested positive, 17.9%). Among 541 participants with nonadvanced neoplasms or negative findings on colonoscopy, the specificity of the DNA test was 86.9%, compared with a specificity of 93.1% achieved by FIT. Within the control group, the DNA test and FIT yielded a specificity of 90.5% and 94.9% respectively for individuals with negative results on colonoscopy. Conclusions: The novel multi-target fecal DNA test exhibited notably superior sensitivity for both CRC and advanced adenoma cases than the commercially quantitative FIT test, while sacrificing some specificity. Our results suggest that this novel multi-target fecal based test may be used as an effective tool for early detection and pre-screening of CRC. Prospective study will be conducted to further evaluate the clinical performance and cost-effectiveness of this assay.

The inequity in emergency room utilization prior to colorectal cancer diagnosis and the opportunity to improve access to colorectal cancer screening.

79 Background: The opportunity for early detection of colorectal cancer via screening is not fully realized. Previous efforts to maximize use of screening had targeted patients and primary care providers. Other wildly used healthcare settings may be suitable targets for intervention. We explored emergency room (ER) utilization in patients with colorectal cancer prior to their diagnosis using the linkage between California Cancer Registry (CCR) and OSHPD (Office of Statewide Health Planning and Development). Methods: Patients with diagnosis of colorectal cancer 2010-2015 were identified in the CCR and their records were linked with OSHPD (2009 – 2016) to assess ER utilization. This study aimed to evaluate the patterns of ER utilization (all and nay reason for ER visit) prior to the diagnosis of colorectal cancer. Results: A total of 66,451 colorectal cancer patients were identified, of which 57,876 (87%) were linked with OSHPD data. Among the linked population, 41% (23,890) had at least one ER visit prior to their diagnosis of colon cancer. Of the 23,890 with ER visit, 14% had 3 or more ER visits. The median number of days from first ER visit to diagnosis was 539 days (range: 2551 – 1). A total of 14,372 patients (25%) had an ER visit within one year of their colorectal cancer diagnosis. The median age of patients who had ER visits was younger than those who didn’t have an ER visit, 66 vs. 68 years. There was no difference in the number of ER visits between patients 50 and younger and those older than 50 years. There was no significant difference in the stage at presentation between those with prior ER visit and those without. Patients in high socioeconomic status were less likely to have an ER visit prior to colorectal cancer diagnosis (44%) compared to those with low SES status (36%). Patients with private insurance had a significantly lower likelihood of ER visits compared to those with federal and state funded insurance. Conclusions: A significant percentage of patients with colorectal cancer had ER visit prior to their diagnosis, many within one year of their diagnosis. Inequity in access to care, measured via poor SES and insurance type, was associated with higher chance of ER visit among colorectal cancer patients. Emergency room may be a targetable opportunity to remind and coordinate screening for colorectal cancer.

Novel blood-based biomarker candidates in screening for colorectal cancer.

244 Background: Colorectal cancer (CRC) is the third most common cancer worldwide motivating national screening strategies utilizing fecal immunochemical tests (FIT). Blood-based biomarkers could be an alternative method to increase compliance in population-based screening programs for early detection of CRC. We aimed to identify new blood-based biomarkers that could be potential candidates for use in colorectal cancer screening. Methods: In a nested cohort study of 1967 FIT positive participants of the Danish CRC screening program serum levels of GDF-15, hepsin, IL-8, keratin1-10, L1CAM, MIA, monocyte MCP-1, NSE and OPG were measured using the Luminex xMAP immunoassay platform. Main outcomes were CRC vs non-CRC and CRC, high-risk adenomas (HRA) or medium-risk adenomas (MRA) vs low-risk adenomas (LRA) or clean colorectum. Odds ratios for associations between biomarker expressions and outcomes were calculated using logistic regression models and visualized by area under the receiver operating characteristic (ROC) curve (AUC). Analyses were made on the Luminex biomarkers alone and with addition of clinical and demographic information. Results: FIT-induced colonoscopies detected 240 CRCs and 625 HRA or MRA. Multivariate analyses using all biomarkers and age found hepsin, IL-8 and OPG significantly (p<0.001) associated in relation to the main outcome (CRC vs non-CRC) with odds ratios of 0.74 [0.59-0.92], 2.59 [2.12-3.15] and 0.90 [0.82-0.99], respectively. The full model using all biomarkers and age presented an AUC of 0.73 [0.70-0.77]. Conclusions: Changed serum levels of nine novel biomarkers seem to be potential predictors for early detection of CRC, especially hepsin, IL-8 and OPG. [Table: see text]

Use of methylation and fragmentation signals in the detection of early-stage colorectal cancer.

201 Background: Colorectal cancer (CRC) remains a leading cause of cancer related mortality worldwide. We utilized cell-free DNA (cfDNA) methylation and fragmentation characteristics of selected cancer-related biomarker regions and applied tumor-derived signal deduction and a machine learning algorithm to refine a blood test for the early detection of CRC. Methods: This was a prospective, international (Spain, Ukraine, Germany and USA [part of NCT04792684 study] population), observational cohort study. Plasma samples were collected either prior to a scheduled screening colonoscopy or prior to colonic surgery for primary CRC. 95 cfDNA samples from 48 early stage (I-II), 47 late-stage (III-IV) CRC patients (mean age 65 [48-83], female 45%, distal cancers 51%) and 204 age, gender and country of origin matched colonoscopy-checked controls were analyzed. 79 of the control patients had a negative colonoscopy finding (cNEG), 96 had benign findings of diverticulosis, hemorrhoids and/or hyperplastic polyps (BEN), 29 had non-advanced adenomas (NAA). Samples were analyzed utilizing previously described hybrid-capture based sequencing methodology. Panel of targeted biomarkers was previously identified through tissue- and plasma-based discovery and further narrowed down through cancer-related biological pathways analysis workflow. Individual cfDNA fragments belonging to each biomarker region were scored for cancer-specific signal. Finally, calculated scores were used in prediction model building and testing for establishing panel accuracy for CRC detection. Results: Prediction model utilizing a panel of methylation and fragmentation scores originating from cfDNA biomarkers belonging to relevant cancer development and progression related pathways, such as axonal guidance, ephrin receptor signaling, epithelial-mesenchymal transition and FGF signaling, correctly classified 92% (87/95) of CRC patients. Sensitivity per cancer stage ranged from 91% (21/23) for stage I, 92% (23/25) for stage II, 91% (30/33) for stage III and 93% (13/14) for stage IV. Fragmentation signals contributed most to early-stage cancers (I-II), while methylation signals were more significant for late stage (III-IV) detection. Specificity of the model was 94% (199/204), with 97% (28/29) NAA, 91% (87/96) BEN and 96% (76/79) cNEG patients correctly identified. Lesion location, gender, age and country of origin were not significantly correlated to prediction outcome. Conclusions: Use of methylation and fragmentation characteristics of cancer-related cfDNA regions, combined with a machine-learning algorithm is highly accurate for early-stage (I-II) CRCs (92% sensitivity at 94% specificity). The study is being further expanded on larger cohort for validation of a highly accurate and minimally invasive blood-based CRC screening test.

The impact of diabetes on cancer detection during the prevalence round of a national screening program for colorectal cancer.

Diabetes is associated with a higher risk of colorectal cancer (CRC) and inferior survival after CRC. Screening may enable the early detection of CRC. We aimed to assess the impact of diabetes on cancer detection and disease stage during the prevalence round of a national CRC screening program. We performed a register-based cohort study based on the randomized procedure for inviting Danish residents aged 50-74 years to the prevalence round of national CRC screening program in 2014-2017. By comparing the random half of the population who had been invited by 1 May 2016 with the not yet invited half, the effect of screening was assessed by the detection of CRC and disease stage among individuals with and without diabetes. Further, the impact of diabetes on the screening participation rate was calculated. By randomisation, 504,673 individuals had been invited to the CRC screening by 1 May 2016, and 549,359 individuals had not yet been invited. The diabetes prevalence was 10% in both groups. When comparing those not yet invited to those invited, the effect of screening on the number of detected cancers per 100,000 individuals was higher in those with diabetes (from 207 to 494 cancers) than in those without diabetes (from 147 to 364 cancers), and screening resulted in overall higher proportions of stage I cancer. Among those invited to screening, the participation rate was 9.1% lower (95% CI: 8.7%-9.5%) in individuals with versus without diabetes. Despite a lower participation rate, the effect of CRC screening was higher in individuals with diabetes.

Production of Monoclonal antibodies to membrane components of human colorectal cancer HCT-116 cell line for diagnostic purposes

Colorectal cancer (CRC) is the second leading cause of cancer-related death worldwide. The survival rate of people diagnosed in the early stages of disease is 92 % whereas; less than 11 % of patients survive if reached stage IV. Moreover, only 24 % of cases are diagnosed during stage I. Thus, the early diagnosis of the CRC will save many lives, reduce suffering of patients. Biomarkers that are in use for the diagnosis of CRC such as Carcinoembryonic Antigen (CEA), Carbohydrate Antigen (CA 19–9) suffer from low sensitivity, expressed in other neoplasms, and not expressed in early stages of cancer. This study aims to find a highly sensitive and specific biomarker for early detection of CRC. Hybridoma clones were established by fusing spleen cells from mice hyperimmunized with human cell membrane homogenate of HCT116 with murine myeloma cells X63Ag8. One clone was selected after fusion and designated as D2C5. Isotyping of secretory antibody revealed an IgG1 kappa light chain and was reactive to a protein with molecular weight about 55 kDa using immunoblot. In situ reactivity of the D2C5 showed homogenous and cytoplasmic pattern staining in stage IV and III, discrete and heterogeneous pattern was seen in stage II samples. Moreover, nuclear staining pattern was seen in one slide of stage II samples. In addition, mucinous type was detected. Low peripheral staining was observed in normal colon tissue. These observations suggest the localization of the target protein in the cytoplasm of epithelial cells with high expression in more advanced cases, suggesting a cytokeratin pattern of staining.

Early detection of colorectal cancer using symptoms and the ColonFlag: case-control and cohort studies

Background: Early detection of colorectal cancer confers substantial prognostic benefit. Most symptoms are non-specific and easily missed. The ColonFlag algorithm identifies risk of undiagnosed colorectal cancer using age, sex and changes in full blood count (FBC) indices. The aim of this study was to investigate whether the ColonFlag detects undiagnosed colorectal cancer prior to the recording of symptoms in general practice. Methods: We conducted case-control and cohort studies by linking primary care data from the Clinical Practice Research Datalink with colorectal cancer diagnoses from the National Cancer Registry. A ColonFlag score was derived for each FBC. We assessed the prevalence of symptoms at six-monthly intervals prior to index date (diagnosis date for cases, randomly selected date for controls). We then derived odds ratios (ORs) and area under the receiver operating characteristic (AUROC) curve for the ColonFlag, and for symptoms using logistic regression at each interval (primary outcome 18-24 months). Results: We included 1,893,641 patients, 10,875,556 FBCs and 8,918,037 ColonFlag scores. ColonFlag scores began to increase in cases compared with controls around 3-4 years before diagnosis. The AUROC for a diagnosis 18-24 months following the ColonFlag score was 0.736 (95% CI 0.715-0.759), falling to 0.536 (95% CI 0.523-0.548) with adjustment for age. ORs for individual symptoms became non-significant prior to 12 months before index date, except for abdominal pain (females OR=1.29, p<0.0001 at 12-18 months) and rectal bleeding (females OR=2.09, males OR=1.92, p<0.0001 at 18-24 months). Conclusions: Symptoms appear relatively late in the colorectal cancer process and are limited for supporting early stage detection. The ColonFlag can discriminate usefully at 18-24 months before diagnosis, suggesting a role for this algorithm in primary care, although some of its discriminatory ability comes from the age variable.

The effect of physician density on colorectal cancer stage at diagnosis: causal inference methods for spatial data applied on regional-level data

BackgroundThe early detection of colorectal cancer (CRC) through regular screening decreases its incidence and mortality rates and improves survival rates. Norway has an extremely high percentage of CRC cases diagnosed at late stages, with large variations across municipalities and hospital catchment areas. This study examined whether the availability of physicians related to CRC primary diagnosis and preoperative investigations, or physician density, contributes to the observed geographical differences in late-stage incidence rates.MethodMunicipality-level data on CRC stage at diagnosis were obtained from the Cancer Registry of Norway for the period 2012–2020. Physician density was calculated as the number of physicians related to CRC investigations, general practitioners (GPs) and specialists per 10,000 people, using physician counts per municipality and hospital areas from Statistics Norway. The relationship was examined using a novel causal inference method for spatial data—neighbourhood adjustment method via spatial smoothing (NA approach)—which allowed for studying the region-level effect of physician supply on CRC outcome by using spatially referenced data and still providing causal relationships.ResultsAccording to the NA approach, an increase in one general practitioner per 10,000 people will result in a 3.6% (CI −0.064 to −0.008) decrease in late-stage CRC rates. For specialists, there was no evidence of a significant correlation with late-stage CRC distribution, while for both groups, GPs and specialists combined, an increase of 1 physician per 10,000 people would be equal to an average decrease in late-stage incidence rates by 2.79% (CI −0.055 to −0.001).ConclusionThe study confirmed previous findings that an increase in GP supply will significantly improve CRC outcomes. In contrast to previous research, this study identified the importance of accessibility to both groups of physicians—GPs and specialists. If GPs encounter insufficient workforces in hospitals and long delays in colonoscopy scheduling, they will less often recommend colonoscopy examinations to patients. This study also highlighted the efficiency of the novel methodology for spatially referenced data, which allowed us to study the effect of physician density on cancer outcomes within a causal inference framework.

Liquid biopsy approaches and immunotherapy in colorectal cancer for precision medicine: Are we there yet?

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths globally, with nearly half of patients detected in the advanced stages. This is due to the fact that symptoms associated with CRC often do not appear until the cancer has reached an advanced stage. This suggests that CRC is a cancer with a slow progression, making it curable and preventive if detected in its early stage. Therefore, there is an urgent clinical need to improve CRC early detection and personalize therapy for patients with this cancer. Recently, liquid biopsy as a non-invasive or nominally invasive approach has attracted considerable interest for its real-time disease monitoring capability through repeated sample analysis. Several studies in CRC have revealed the potential for liquid biopsy application in a real clinical setting using circulating RNA/miRNA, circulating tumor cells (CTCs), exosomes, etc. However, Liquid biopsy still remains a challenge since there are currently no promising results with high specificity and specificity that might be employed as optimal circulatory biomarkers. Therefore, in this review, we conferred the plausible role of less explored liquid biopsy components like mitochondrial DNA (mtDNA), organoid model of CTCs, and circulating cancer-associated fibroblasts (cCAFs); which may allow researchers to develop improved strategies to unravel unfulfilled clinical requirements in CRC patients. Moreover, we have also discussed immunotherapy approaches to improve the prognosis of MSI (Microsatellite Instability) CRC patients using neoantigens and immune cells in the tumor microenvironment (TME) as a liquid biopsy approach in detail.

Stool DNA testing for early detection of colorectal cancer: systematic review using the HTA Core Model® for Rapid Relative Effectiveness Assessment.

Stool DNA testing for early detection of colorectal cancer (CRC) is a non-invasive technology with the potential to supplement established CRC screening tests. The aim of this health technology assessment was to evaluate effectiveness and safety of currently CE-marked stool DNA tests, compared to other CRC tests in CRC screening strategies in an asymptomatic screening population. The assessment was carried out following the guidelines of the European Network for Health Technology Assessment (EUnetHTA). This included a systematic literature search in MED-LINE, Cochrane and EMBASE in 2018. Manufacturers were asked to provide additional data. Five patient interviews helped assessing potential ethical or social aspects and patients' experiences and preferences. We assessed the risk of bias using QUADAS-2, and the quality of the body of evidence using GRADE. We identified three test accuracy studies, two of which investigated a multitarget stool DNA test (Cologuard®, compared fecal immunochemical test (FIT)) and one a combined DNA stool assay (ColoAlert®, compared to guaiac-based fecal occult blood test (gFOBT), Pyruvate Kinase Isoenzyme Type M2 (M2-PK) and combined gFOBT/M2-PK). We found five published surveys on patient satisfaction. No primary study investigating screening effects on CRC incidence or on overall mortality was found. Both stool DNA tests showed in direct comparison higher sensitivity for the detection of CRC and (advanced) adenoma compared to FIT, or gFOBT, respectively, but had lower specificity. However, these comparative results may depend on the exact type of FIT used. The reported test failure rates were higher for stool DNA testing than for FIT. The certainty of evidence was moderate to high for Cologuard® studies, and low to very low for the ColoAlert® study which refers to a former version of the product and yielded no direct evidence on the test accuracy for ad-vanced versus non-advanced adenoma. ColoAlert® is the only stool DNA test currently sold in Europe and is available at a lower price than Cologuard®, but reliable evidence is lacking. A screening study including the current product version of ColoAlert® and suitable comparators would, therefore, help evaluate the effectiveness of this screening option in a European context.