Systematic review of colorectal cancer screening guidelines for average-risk adults: Summarizing the current global recommendations

Economic evaluations of screening strategies for the early detection of colorectal cancer in the average-risk population: A systematic literature review

Background

Colorectal cancer (CRC) screening has proven effective in reducing CRC mortality. This study aimed to systematically review, and evaluate the reporting quality, of the economic evidence regarding CRC screening in average-risk individuals.

Methods

Databases searched included Medline, EMBASE, National Health Service Economic Evaluation, Database of Abstracts of Reviews of Effects, Cost-Effectiveness Analysis registry, EconLit, and Health Technology Assessment database. Eligible studies were cost-effectiveness and cost-utility analyses comparing CRC screening strategies in average-risk individuals, published in English or Spanish, between January 2012 and November 2018. Reporting quality was assessed using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist.

Results

Of 1,993 publications initially retrieved, 477 were excluded by duplicate review, 1,449 by title/abstract review, and 34 by full-text review. Finally, 33 publications were included in the qualitative synthesis. Most studies were conducted in Europe (36,4%), followed by United States (24,2%) and Asia (24,2%). The main screening modalities considered were fecal immunochemical tests (70%), colonoscopy (67%), guaiac fecal occult blood test (42%) and flexible sigmoidoscopy (30%). In most studies, CRC screening was deemed cost-effective compared to no screening. Sensitivity analyses indicated that cost of CRC screening tests, adherence to screening, screening test sensitivity, and cost of CRC treatment had the greatest impact on cost-effectiveness results across studies. The majority of studies (73%) adequately reported at least 50% of the items included in the CHEERS checklist. Least well reported items included setting, study perspective, discount rate, model choice, and methods to identify effectiveness data or to estimate resource use and costs.

Conclusions

CRC screening is an efficient alternative to no screening. Nevertheless, it is not possible to conclude which strategy should be preferred for population-based screening programs. Although we observed an overall good adherence to CHEERS recommendations, there is still room for improvement in economic evaluations reporting in this field.

Attitudes and perceptions of people with a learning disability, family carers, and paid care workers towards cancer screening programmes in the United Kingdom: A qualitative systematic review and meta-aggregation

OBJECTIVE

Evidence suggests that people with a learning disability (PwLD) are less likely to attend cancer screening than the general population in the United Kingdom. The aim of this systematic review was to identify and synthesise qualitative studies reporting the attitudes and opinions of PwLD, family carers, and paid care workers towards national cancer screening programmes.

METHODS

Five electronic and two grey literature databases were searched. Fourteen thousand eight hundred forty-six papers were reviewed against predetermined inclusion criteria. Included papers were critically appraised. Findings were synthesised using meta-aggregation.

RESULTS

Eleven papers met the inclusion criteria, all related to cervical and breast screening. No papers were related to colorectal cancer screening. Findings were clustered into four synthesised findings: (1) supporting women with a learning disability (WwLD) to attend screening, (2) WwLD's awareness of screening and their psychophysical experiences, 3) professional practice barriers including the need for multidisciplinary working and an understanding of the needs of WwLD, and (4) approaches to improve the uptake of cervical and breast cancer screening. The synthesis highlights the significance of WwLD having support to understand the importance of screening to be able to make an informed choice about attending.

CONCLUSIONS

WwLD may not attend cancer screening due to fear, concerns over pain, and the potential influence of family carers and paid care workers. The review identified practical mechanisms which could help WwLD attend screening. Future research should focus on identifying potential barriers and facilitators as a proactive measure to promote colorectal cancer screening.

Improvement of Asia-Pacific colorectal screening score and evaluation of its use combined with fecal immunochemical test

Background

The Asia-Pacific Colorectal Screening (APCS) score is effective to screen high-risk groups of advanced colorectal neoplasia (ACN) patients but needs revising and can be combined with the fecal immunochemical test (FIT). This paper aimed to improve the APCS score and evaluate its use with the FIT in stratifying the risk of ACN.

Methods

This prospective and multicenter study enrolled 955 and 1201 asymptomatic Chinese participants to form the derivation and validation set, respectively. Participants received the risk factor questionnaire, colonoscopy and FIT. Multiple logistic regression was applied, and C-statistic, sensitivity and negative predictive values (NPVs) were used to compare the screening efficiency.

Results

A modified model was developed incorporating age, body mass index (BMI), family history, diabetes, smoking and drinking as risk factors, stratifying subjects into average risk (AR) or high risk (HR). In the validation set, the HR tier group had a 3.4-fold (95% CI 1.8–6.4) increased risk for ACN. The C-statistic for the modified score was 0.69 ± 0.04, and 0.67 ± 0.04 for the original score. The sensitivity of the modified APCS score combined with FIT for screening ACN high-risk cohorts was 76.7% compared with 36.7% of FIT alone and 70.0% of the modified APCS score alone. The NPVs of the modified score combined with FIT for ACN were 98.0% compared with 97.0% of FIT alone and 97.9% of the modified APCS score alone.

Conclusions

The modified score and its use with the FIT are efficient in selecting the HR group from a Chinese asymptomatic population.

Protein expression trends of DNMT1 in gastrointestinal diseases: From benign to precancerous lesions to cancer

BACKGROUND

In recent years, the incidence of gastrointestinal (GI) cancer in China has increased annually. Early detection and appropriate therapy are considered to be the key to treat GI cancer. DNMT1 takes an active part in the advancement of GI cancer, which will change as the disease progresses. But its expression characteristics in the dynamic variations of GI carcinogenesis are still unclear.

AIM

To investigate the expression characteristics of DNMT1 in different GI diseases.

METHODS

We detected the expression of DNMT1 in 650 cases of different GI diseases by immunohistochemistry, including 90 cases of chronic superficial gastritis (CSG), 72 cases of atrophic gastritis with intestinal metaplasia (AG/GIM), 54 cases of low-grade intraepithelial neoplasia (GLIN), 66 cases of high-grade intraepithelial neoplasia (GHIN), 71 cases of early gastric cancer (EGC), 90 cases of normal intestinal mucosa (NIM), 54 cases of intestinal low-grade intraepithelial neoplasia (ILIN), 71 cases of intestinal high-grade intraepithelial neoplasia (IHIN), and 82 cases of early colorectal cancer (ECRC).

RESULTS

In the CSG group, all cases showed weakly positive or negative expression of DNMT1. However, in other four groups (AG/GIM, GLIN, GHIN, and EGC), the positive expression rate gradually increased with the severity of the diseases; the negative or weakly positive cases accounted for 55.56% (40/72), 38.89% (21/54), 1.52% (1/66), and 1.41% (1/71), respectively. Besides, the moderately positive cases were 44.44% (32/72), 57.41% (31/54), 80.30% (53/66), and 43.66% (31/71), respectively. The strongly positive cases only existed in the GLIN (3.70%, 2/54), GHIN (18.18%, 12/66), and EGC (54.93%, 39/71) groups. The differences between any two groups were statistically significant (P < 0.05). Similarly, in the NIM group, cases with weakly positive expression of DNMT1 were predominant (91.11%, 82/90), and the rest were moderately positive cases (8.89%, 8/90). In the ILIN, IHIN, and ECRC groups, the rates of cases with weak or negative expression of DNMT1 were 46.30% (25/54), 12.68% (9/71), and 4.88% (4/82), respectively; with moderately positive expression were 53.70% (29/54), 71.83% (51/71), and 34.15% (28/82), respectively; and with strongly positive expression were 0.00% (0/54), 15.49% (11/71), and 60.98% (50/82), respectively. The differences between any two groups were also statistically significant (P < 0.05).

CONCLUSION

The overexpression of DNMT1 protein could effectively predict early GI cancers and severe precancerous lesions, which may have potential clinical application value.

ILC2s: New Actors in Tumor Immunity

Innate lymphoid cells (ILCs) represent the most recently identified family of innate lymphocytes that act as first responders, maintaining tissue homeostasis and protecting epithelial barriers. In the last few years, group 2 ILCs (ILC2s) have emerged as key regulators in several immunological processes such as asthma and allergy. Whilst ILC2s are currently being evaluated as novel targets for immunotherapy in these diseases, their involvement in tumor immunity has only recently begun to be deciphered. Here, we provide a comprehensive overview of the pleiotropic roles of ILC2s in different tumor settings. Furthermore, we discuss how different therapeutic approaches targeting ILC2s could improve the efficacy of current tumor immunotherapies.

Outcomes at follow-up of negative colonoscopy in average risk population: systematic review and meta-analysis

OBJECTIVE

To review and summarise the evidence on the prevalence of colorectal adenomas and cancers at a follow-up screening colonoscopy after negative index colonoscopy, stratified by interval between examinations and by sex.

DESIGN

Systematic review and meta-analysis of all available studies.

DATA SOURCES

PubMed, Web of Science, and Embase. Two investigators independently extracted characteristics and results of identified studies and performed standardised quality ratings.

ELIGIBILITY CRITERIA

Studies assessing the outcome of a follow-up colonoscopy among participants at average risk for colorectal cancer with a negative previous colonoscopy (no adenomas).

RESULTS

28 studies were identified, including 22 cohort studies, five cross sectional studies, and one case-control study. Findings for an interval between colonoscopies of one to five, five to 10, and more than 10 years were reported by 17, 16, and three studies, respectively. Summary estimates of prevalences of any neoplasm were 20.7% (95% confidence interval 15.8% to 25.5%), 23.0% (18.0% to 28.0%), and 21.9% (14.9% to 29.0%) for one to five, five to 10, and more than 10 years between colonoscopies. Corresponding summary estimates of prevalences of any advanced neoplasm were 2.8% (2.0% to 3.7%), 3.2% (2.2% to 4.1%), and 7.0% (5.3% to 8.7%). Seven studies also reported findings stratified by sex. Summary estimates stratified by interval and sex were consistently higher for men than for women.

CONCLUSIONS

Although detection of any neoplasms was observed in more than 20% of participants within five years of a negative screening colonoscopy, detection of advanced neoplasms within 10 years was rare. Our findings suggest that 10 year intervals for colonoscopy screening after a negative colonoscopy, as currently recommended, may be adequate, but more studies are needed to strengthen the empirical basis for pertinent recommendations and to investigate even longer intervals.

STUDY REGISTRATION

Prospero CRD42019127842.

Diagnostic value of fecal B cell activating factor in patients with abdominal discomfort

Fecal calprotectin has successfully been widely recommended as a sensitive biomarker of inflammatory bowel diseases (IBD). Recently, we have identified an excellent new fecal biomarker, B cell activating factor (BAFF), as being as effective as fecal calprotectin for diagnosing intestinal inflammation. In this study, a total of 230 patients with abdominal discomfort were prospectively enrolled and fecal samples were collected within 24 h before the endoscopic examinations. We show that fecal BAFF levels were significantly higher in patients with ulcerative colitis (median = 1549 pg/g, P < 0·0001), Crohn's disease (median = 735 pg/g, P < 0·0001), gastric cancer (median = 267 pg/g, P < 0·0001) and colorectal cancer (median = 533 pg/g, P < 0·0001) than those in healthy groups (median = 61 pg/g), while the values of which in patients with gastric polyps, colorectal polyps, esophagitis/gastritis/duodenitis and peptic ulcer were in the range of healthy individuals (P > 0·05). An optimal cut-off value at 219·5 pg/g of fecal BAFF produced sensitivity, specificity, positive predictive and negative predictive values of 85, 91, 84 and 92%, respectively, for IBD or carcinoma. Our results therefore indicate a potential role for fecal BAFF as a sensitive screening parameter for IBD and gastrointestinal carcinoma, as well a useful tool to select patients with abdominal discomfort for further endoscopic examinations.

Circulating molecular biomarkers for screening or early diagnosis of colorectal cancer: which is ready for prime time?

According to recent statistics, colorectal cancer (CRC) is a frequent disease, the second most frequent malignancy in women and the third most common malignant disease in men, respectively. Although reinforced emphasis on CRC screening by means of immunochemical fecal occult blood test, colonoscopy or sigmoidoscopy has contributed to decrease cancer-related deaths, alternative diagnostic tests would be needed for establishing earlier and more potentially effective treatments. Innovative diagnostic techniques have recently emerged, some of which hold promises for screening and/or early CRC detection. Recent evidence suggests that the so-called "liquid biopsy", conventionally defined as detection and quantification of circulating tumor cells (CTCs) and cancer-related nucleic acids in peripheral blood, may allow earlier diagnosis of CRC combined with lower invasiveness and less patient inconvenience, higher throughput, faster turnaround time, inferior usage of healthcare resources and relatively low cost. Encouraging data have emerged from trials based on CTCs detection, though the sensitivity of the current diagnostic techniques is still perhaps insufficient for enabling early CRC diagnosis. Among the various biomarkers that can be detected with liquid biopsy, SEPT9 methylation displays good diagnostic performance and relatively high cancer detection rate (between 57-64% in patients with CRC stages 0-I), which would make this test a promising tool for population screening, alone or in combination with other conventional diagnostic investigations. Encouraging evidence has also been recently published for BCAT1/IKZF1 methylation. Regarding microRNA (miRNAs), the available evidence highlights that the combination of some of these biomarkers rather than the assessment of a single miRNA alone would enable efficient identification of early CRCs, though widespread clinical application is still challenged by a number of preanalytical, analytical and clinical issues.

Efficacy and clinical monitoring strategies for immune checkpoint inhibitors and targeted cytokine immunotherapy for locally advanced and metastatic colorectal cancer

Colorectal cancer (CRC) is the fourth most common cancer type and is the second leading cause of cancer deaths annually in the United States. Conventional treatment options include postoperative (adjuvant) and preoperative (neoadjuvant) chemotherapy and radiotherapy. Although these treatment modalities have shown to decrease tumor burden, a major limitation to chemothearpy/radiotherapy is the high recurrence rate in patients. Immune-modulation strategies have emerged as a promising new therapeutic avenue to reduce this recurrence rate while minimizing undesirable systemic side effects. This review will focus specifically on the mechanisms of monoclonal antibodies: immune checkpoint inhibitors and cytokines, as well as current drugs approved by the Food and Drug Administration (FDA) and new clinical/pre-clinical trials. Finally, this review will investigate emerging methods used to monitor tumor response post-treatment.

BZW2 promotes the malignant progression of colorectal cancer via activating the ERK/MAPK pathway

Colorectal cancer (CRC) is one of the most prevalent malignant solid cancers worldwide involving the dysregulation of multiple signaling molecules. However, the role and corresponding mechanism of basic leucine zipper and W2 domains 2 (BZW2) in CRC development, to our knowledge, has not been reported. We found BZW2 was overexpressed in human CRC tissues compared with that in paired adjacent colorectal samples. BZW2 overexpression was closely associated with tumor T stage (p = .030), metastatic lymph nodes (p = .037), TNM stage (p = .018) and the worse prognosis of CRC patients (p = .009). Moreover, BZW2 was an independent disadvantage prognostic factor (p = .031). BZW2 also showed an increased expression in different invasive CRC cell lines. Its silencing and overexpression diminished and increased cell proliferation, invasion, and migration in Colo205 and HCT116 cells via specifically activating of extracellular-signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) signaling. Moreover, ERK/MAPK inhibitor PD98059 reverse the enhancement of cell proliferation, invasion, and migration in BZW2 overexpressing HCT116 cells. BZW2 silencing also inhibited subcutaneous tumors growth and p-ERK expression in vivo. BZW2 promotes the malignant progression of CRC via activating ERK/MAPK signaling, which provided a promising gene target therapy for CRC.

Colorectal cancer screening with faecal immunochemical testing, sigmoidoscopy or colonoscopy: a clinical practice guideline

CLINICAL QUESTION

Recent 15-year updates of sigmoidoscopy screening trials provide new evidence on the effectiveness of colorectal cancer screening. Prompted by the new evidence, we asked: "Does colorectal cancer screening make an important difference to health outcomes in individuals initiating screening at age 50 to 79? And which screening option is best?"

CURRENT PRACTICE

Numerous guidelines recommend screening, but vary on recommended test, age and screening frequency. This guideline looks at the evidence and makes recommendations on screening for four screening options: faecal immunochemical test (FIT) every year, FIT every two years, a single sigmoidoscopy, or a single colonoscopy.

RECOMMENDATIONS

These recommendations apply to adults aged 50-79 years with no prior screening, no symptoms of colorectal cancer, and a life expectancy of at least 15 years. For individuals with an estimated 15-year colorectal cancer risk below 3%, we suggest no screening (weak recommendation). For individuals with an estimated 15-year risk above 3%, we suggest screening with one of the four screening options: FIT every year, FIT every two years, a single sigmoidoscopy, or a single colonoscopy (weak recommendation). With our guidance we publish the linked research, a graphic of the absolute harms and benefits, a clear description of how we reached our value judgments, and linked decision aids.

HOW THIS GUIDELINE WAS CREATED

A guideline panel including patients, clinicians, content experts and methodologists produced these recommendations using GRADE and in adherence with standards for trustworthy guidelines. A linked systematic review of colorectal cancer screening trials and microsimulation modelling were performed to inform the panel of 15-year screening benefits and harms. The panel also reviewed each screening option's practical issues and burdens. Based on their own experience, the panel estimated the magnitude of benefit typical members of the population would value to opt for screening and used the benefit thresholds to inform their recommendations.

THE EVIDENCE

Overall there was substantial uncertainty (low certainty evidence) regarding the 15-year benefits, burdens and harms of screening. Best estimates suggested that all four screening options resulted in similar colorectal cancer mortality reductions. FIT every two years may have little or no effect on cancer incidence over 15 years, while FIT every year, sigmoidoscopy, and colonoscopy may reduce cancer incidence, although for FIT the incidence reduction is small compared with sigmoidoscopy and colonoscopy. Screening related serious gastrointestinal and cardiovascular adverse events are rare. The magnitude of the benefits is dependent on the individual risk, while harms and burdens are less strongly associated with cancer risk.

UNDERSTANDING THE RECOMMENDATION

Based on benefits, harms, and burdens of screening, the panel inferred that most informed individuals with a 15-year risk of colorectal cancer of 3% or higher are likely to choose screening, and most individuals with a risk of below 3% are likely to decline screening. Given varying values and preferences, optimal care will require shared decision making.

Colorectal cancer screening with faecal testing, sigmoidoscopy or colonoscopy: a systematic review and network meta-analysis

OBJECTIVE

Evaluate effectiveness, harms and burdens of faecal blood testing, sigmoidoscopy and colonoscopy screening for colorectal cancer over 15 years.

DESIGN

We performed an update of a Cochrane systematic review, and performed network meta-analysis comparing randomised trials evaluating colorectal cancer screening with guaiac faecal occult blood test (gFOBT) (annual, biennial), faecal immunochemical test (FIT) (annual, biennial), sigmoidoscopy (once-only) or colonoscopy (once-only) in a healthy population, aged 50-79 years. We conducted subgroup analysis on sex. Follow-up >5 years was required for analysis of colorectal cancer incidence and mortality.

RESULTS

12 randomised trials proved eligible. Compared with no-screening, we found high certainty evidence for sigmoidoscopy screening slightly reducing colorectal cancer incidence (relative risk (RR) 0.76; 95% confidence interval (CI 0.70 to 0.83) and mortality (RR 0.74; 95% CI 0.69 to 0.80), while gFOBT screening had little or no difference on colorectal cancer incidence, but slightly reduced colorectal cancer mortality (annual: RR 0.69; 95% CI 0.56 to 0.86, biennial: RR 0.88; 95% CI 0.82 to 0.93). No screening test reduced mortality nor incidence by more than six per 1000 screened over 15 years. Sigmoidoscopy had a greater effect in men, for both colorectal cancer incidence (women: RR 0.86; 95% CI 0.81 to 0.92, men: RR 0.75, 95% CI 0.71 to 0.79), and mortality (women: RR 0.85; 95% CI 0.71 to 0.96, men: RR 0.67; 95% CI 0.61 to 0.75) (moderate certainty).

CONCLUSIONS

In a 15-year perspective, sigmoidoscopy reduces colorectal cancer incidence, while sigmoidoscopy, annual and biennial gFOBT all reduce colorectal cancer mortality. Sigmoidoscopy may reduce colorectal cancer incidence and mortality more in men than in women.

PROSPERO REGISTRATION NUMBER

CRD42018093401.

Forceps Biopsies Are Not Reliable in the Workup of Large Colorectal Lesions Referred for Endoscopic Resection: Should They Be Abandoned?

BACKGROUND

Biopsies are routinely obtained in the workup of large colorectal polyps before endoscopic resection.

OBJECTIVE

This study aimed to examine how reliable biopsies are in terms of reflecting the true histopathology of large colorectal polyps, in the clinical routine.

DESIGN

This is a retrospective study.

SETTINGS

Data from patients undergoing polypectomy of large colorectal polyps at the endoscopy unit, Skåne University Hospital Malmö, between January 2014 and December 2016 were scrutinized.

PATIENTS

A total of 485 colorectal lesions were biopsied within 1 year before complete endoscopic removal. Biopsy-obtained specimens were compared with completely resected specimens in terms of concordance and discordance and if the final result was upgraded or downgraded.

MAIN OUTCOME MEASURES

The primary outcome measured was the concordance between biopsy-obtained specimens and completely resected specimens.

RESULTS

Median lesion size was 3 cm (range 1-11). In 189 cases (39%), biopsies did not provide a correct dysplastic grade compared with final pathology after complete resection. One hundred forty-three cases (29%) and 46 cases (9%) were upgraded and downgraded. The percentage of cases with discordant biopsy results was 40% in cases with 1 biopsy taken and 38% in cases where multiple biopsies had been sampled. Time from biopsy to complete resection did not influence the erroneous outcome of biopsies. Notably, the percentage of discordant biopsy results was 37% and 35% in lesions measuring 1 to 2 cm and 2 to 4 cm. However, this percentage increased to 48% in colorectal lesions larger than 4 cm.

LIMITATIONS

This study was designed to reflect the clinical routine, the number of biopsies obtained and forceps technique were hence not standardized, which constitutes a limitation.

CONCLUSIONS

This study demonstrates that cancer-negative forceps biopsies of large colorectal polyps, referred for endoscopic resection, are not reliable. Considering that endoscopic resection of lesions containing superficial cancer is plausible, the clinical value of forceps biopsies in lesions suitable for endoscopic resection is questionable. See Video Abstract at http://links.lww.com/DCR/A984. LAS BIOPSIAS CON FÓRCEPS NO SON CONFIABLES EN EL ESTUDIO DE LAS LESIONES COLORRECTALES GRANDES REFERIDAS PARA RESECCIÓN ENDOSCÓPICA: ¿DEBERÍAN ABANDONARSE?: Las biopsias se obtienen de forma rutinaria en el estudio de pólipos colorrectales grandes previo a resección endoscópica.

OBJETIVO

Analizar que tan confiables son las biopsias en cuanto a reflejar la verdadera histopatología de los pólipos colorrectales grandes, en la rutina clínica. DISEÑO:: Este es un estudio retrospectivo.

AJUSTES

Los datos de pacientes sometidos a polipectomía de pólipos colorrectales grandes en la unidad de endoscopia, en Skåne University Hospital Malmö, entre enero de 2014 y diciembre de 2016 fueron examinados.

PACIENTES

Un total de 485 lesiones colorrectales se biopsiaron dentro de un año antes de la resección endoscópica completa. Las muestras obtenidas mediante biopsia se compararon con las muestras completas resecadas en términos de concordancia y discordancia, y si el resultado final ascendió o disminuyó de categoría.

PRINCIPALES MEDIDAS DE RESULTADO

Concordancia entre muestras obtenidas mediante biopsia y muestras completamente resecadas.

RESULTADOS

La mediana de tamaño de lesiones fue de 3 cm (rango 1-11). En 189 casos (39%) las biopsias no proporcionaron un grado de displasia correcto en comparación con la patología final después de la resección completa. 143 casos (29%) y 46 casos (9%) ascendieron y descendieron de categoría, respectivamente. El porcentaje de casos con resultados de biopsia discordantes fue del 40% en los casos con una sola biopsia tomada y del 38% en los casos en los que se tomaron múltiples biopsias. El tiempo desde la biopsia hasta la resección completa no influyó en el resultado erróneo de las biopsias. Notablemente, el porcentaje de resultados de biopsia discordantes fue de 37% y 35% en lesiones que midieron 1-2 cm y 2-4 cm, respectivamente. Sin embargo, este porcentaje aumentó a 48% en lesiones colorrectales mayores de 4 cm.

LIMITACIONES

Este estudio se diseñó para reflejar la rutina clínica, el número de biopsias obtenidas y la técnica de fórceps no fueron estandarizadas, lo que constituye una limitación.

CONCLUSIONES

Este estudio demuestra que las biopsias con fórceps negativas a cáncer, de pólipos colorrectales grandes referidas para resección endoscópica, no son confiables. Teniendo en cuenta que la resección endoscópica de lesiones que contienen cáncer superficial es posible, el valor clínico de las biopsias con fórceps en lesiones aptas para la resección endoscópica es cuestionable. Vea el Resumen en video en http://links.lww.com/DCR/A984.

Colorectal cancer in Saudi Arabia as the proof-of-principle model for implementing strategies of predictive, preventive, and personalized medicine in healthcare

Colorectal cancer (CRC) is the most commonly diagnosed cancer among Saudi males and ranks third in females with up to 73% of cases diagnosed at late stage. This review provides an analysis of CRC situation in the Kingdom of Saudi Arabia (KSA) from healthcare perspective. A PUBMED (1986-2018) search was done to identify publications focusing on CRC in KSA. Due to reports of increased CRC incidence among young age group (< 50), and given the young population of KSA, the disease may burden the national healthcare system in the next decades. Environmental factors attributed to increasing incidence rates of CRC include red meat consumption, sedentary lifestyle, and increased calorie intake. Despite substantial investment in healthcare, attention to predictive diagnostics and targeted prevention is lacking. There is a need to develop national screening guidelines based on evidence that supports a reduction in incidence and mortality of CRC when screening is implemented. Future approaches are discussed based on multi-level diagnostics, risk assessment, and population screening programs focused on the needs of young populations that among others present the contents of the advanced approach by predictive, preventive, and personalized medicine. Recommendations are provided that could help to develop policies at regional and national levels. Countries with demographics and lifestyle similar to KSA may gain insights from this review to shape their policies and procedures.

Scoring colorectal cancer risk with an artificial neural network based on self-reportable personal health data

Colorectal cancer (CRC) is third in prevalence and mortality among all cancers in the US. Currently, the United States Preventative Services Task Force (USPSTF) recommends anyone ages 50-75 and/or with a family history to be screened for CRC. To improve screening specificity and sensitivity, we have built an artificial neural network (ANN) trained on 12 to 14 categories of personal health data from the National Health Interview Survey (NHIS). Years 1997-2016 of the NHIS contain 583,770 respondents who had never received a diagnosis of any cancer and 1409 who had received a diagnosis of CRC within 4 years of taking the survey. The trained ANN has sensitivity of 0.57 ± 0.03, specificity of 0.89 ± 0.02, positive predictive value of 0.0075 ± 0.0003, negative predictive value of 0.999 ± 0.001, and concordance of 0.80 ± 0.05 per the guidelines of Transparent Reporting of Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) level 2a, comparable to current risk-scoring methods. To demonstrate clinical applicability, both USPSTF guidelines and the trained ANN are used to stratify respondents to the 2017 NHIS into low-, medium- and high-risk categories (TRIPOD levels 4 and 2b, respectively). The number of CRC respondents misclassified as low risk is decreased from 35% by screening guidelines to 5% by ANN (in 60 cases). The number of non-CRC respondents misclassified as high risk is decreased from 53% by screening guidelines to 6% by ANN (in 25,457 cases). Our results demonstrate a robustly-tested method of stratifying CRC risk that is non-invasive, cost-effective, and easy to implement publicly.

Analysis of Human Colon by Raman Spectroscopy and Imaging-Elucidation of Biochemical Changes in Carcinogenesis

Noninvasive Raman imaging of non-fixed and unstained human colon tissues based on vibrational properties of noncancerous and cancerous samples can effectively enable the differentiation between noncancerous and tumor tissues. This work aimed to evaluate the biochemical characteristics of colon cancer and the clinical merits of multivariate Raman image and spectroscopy analysis. Tissue samples were collected during routine surgery. The non-fixed, fresh samples were used to prepare micrometer sections from the tumor mass and the tissue from the safety margins outside of the tumor mass. Adjacent sections were used for typical histological analysis. We have found that the chemical composition identified by Raman spectroscopy of the cancerous and the noncancerous colon samples is sufficiently different to distinguish pathologically changed tissue from noncancerous tissue. We present a detailed analysis of Raman spectra for the human noncancerous and cancerous colon tissue. The multivariate analysis of the intensities of lipids/proteins/carotenoids Raman peaks shows that these classes of compounds can statistically divide analyzed samples into noncancerous and pathological groups, reaffirming that Raman imaging is a powerful technique for the histochemical analysis of human tissues. Raman biomarkers based on ratios for lipids/proteins/carotenoids content were found to be the most useful biomarkers in spectroscopic diagnostics.

The Rise of Colorectal Cancer in Asia: Epidemiology, Screening, and Management

PURPOSE OF REVIEW

Colorectal cancer (CRC) remains the third most commonly diagnosed cancer globally, and its incidence and mortality rates have been on the rise in Asia. In this paper, we summarize the recent trends and screening challenges of CRC in this region.

RECENT FINDINGS

In 2018, Asia had the highest proportions of both incident (51.8%) and mortality (52.4%) CRC cases (all genders and ages) per 100,000 population in the world. In addition, there has been a rising trend of this disease across Asia with some regional geographic variations. This rise in CRC can be attributed to westernized dietary lifestyle, increasing population aging, smoking, physical inactivity, and other risk factors. In curbing the rising trend, Japan, South Korea, Singapore, and Taiwan have launched nationwide population-based screening programs. CRC screening across this region has been found to be effective and cost-effective compared with no screening at all. The emergence of new therapies has caused a reduction in case fatality; however, these new options have had a limited impact on cure rates and long-term survival due to the great disparity in treatment capacity/resources and screening infrastructures among Asian countries with different degrees of economic development. CRC is still rising in Asia, and implementation of screening is necessary for moderate- to high-incidence countries and construction of treatment capacity is the priority task in low-incidence and low-income countries. Unless countries in Asia implement CRC screening, the incidence and mortality rates of this disease will continue to rise especially with the rapidly rising population growth, economic development, westernized lifestyle, and increasing aging.

Surveying Gut Microbiome Research in Africans: Toward Improved Diversity and Representation

Descriptive and translational investigations into the human gut microbiome (GM) are rapidly expanding; however, studies are largely restricted to industrialized populations in the USA and Europe. Little is known about microbial variability and its implications for health and disease in other parts of the world. Populations in Africa are particularly underrepresented. What limited research has been performed has focused on a few subject domains, including the impact of long-term lifestyle and dietary factors on GM ecology, its maturation during infancy, and the interrelationships between the microbiome, infectious disease, and undernutrition. Recently, international consortia have laid the groundwork for large-scale genomics and microbiome studies on the continent, with a particular interest in the epidemiologic transition to noncommunicable disease. Here, we survey the current landscape of GM scholarship in Africa and propose actionable recommendations to improve research capacity and output.

Colorectal Cancer Screening Modalities in Chinese Population: Practice and Lessons in Pudong New Area of Shanghai, China

Background: Parallel test of risk stratification and two-sample qualitative fecal immunochemical tests (FITs) are used to screen colorectal cancer (CRC) in Shanghai, China. This study was designed to identify an optimal initial screening modality based on available data. Methods: A total of 538,278 eligible residents participated in the program during the period of January 2013 to June 2017. Incident CRC was collected through program reporting system and by record linkage with the Shanghai Cancer Registry up to December 2017. Logistic regression model was applied to identify significant factors to calculate risk score for CRC. Cutoff points of risk score were determined based on Youden index and defined specificity. Sensitivity, specificity, and positive predictive values (PPVs) were computed to evaluate validity of assumed screening modalities. Results: A total of 446 CRC were screen-detected, and 777 interval or missed cases were identified through record linkage. The risk score system had an optimal cutoff point of 19 and performed better in detecting CRC and predicting long-term CRC risk than did the risk stratification. When using a cutoff point of 24, parallel test of risk score, and FIT were expected to avoid 56 interval CRCs with minimal decrease in PPV and increase in colonoscopy. However, the observed detection rates were much lower than those expected due to low compliance to colonoscopy. Conclusions: Risk score is superior to risk stratification used in the program, particularly when combined with FIT. Compliance to colonoscopy should be improved to guarantee the effectiveness of CRC screening in the population.

Oncological outcome of peripartum colorectal carcinoma-a single-center experience

OBJECTIVES

This study aimed to analyze disease presentation, management, and oncological outcomes of patients diagnosed with peripartum colorectal cancer (CRC).

METHODS

Retrospective cohort study of all consecutive women of childbearing age (18-45 years) between 2002 and 2014 diagnosed with CRC adenocarcinoma at a tertiary academic institution. Patients who experienced pregnancy within 12 months of their diagnosis (peripartum period, group 1) were compared to the remaining patients of the cohort (group 2). Overall survival (OS) was compared between the two groups through Kaplan-Meier estimates.

RESULTS

Out of 555 consecutive women with a mean age of 37.8 + 6 years, 31 (5.6%) were diagnosed with CRC in the peripartum period. Of these, all patients were symptomatic during pregnancy due to bleeding, abdominal pain, or constipation; however, only 11 CRC (35.5%) were diagnosed during pregnancy, 1 (3.2%) during C section, and the remaining (61.3%) postpartum. TNM stage at presentation was I in 6 patients (19.4%), II in 4 patients (13.9%), III in 8 patients (25.8%), and IV in 13 patients (41.9%). Surgical resection was performed in 23 patients (74.2%): 2 while pregnant, 2 at the time of C section, and the remainder postpartum. Across all stages, OS was 95% at 1 year and 62% at 5 years and did not differ between the two comparative groups (p = 0.16).

CONCLUSIONS

A suspicious attitude towards cancer-related symptoms during pregnancy is crucial to prevent delayed evaluation for CRC.

Wait times to diagnosis and treatment in patients with colorectal cancer in Hungary

BACKGROUND

Mortality from colorectal cancer (CRC) in Hungary is the highest in Europe. It was the aim of the present study to determine the wait times from first presentation to diagnosis, in a sample of Hungarian patients with CRC, as well as to assess the stages of CRC at diagnosis.

METHODS

A retrospective study based on data from 212 patients with CRC in Baranya county was carried out. Data extraction was performed from 26 GP practices and from the database of the University of Pécs Clinical Center. Total Diagnostic Interval (TDI) was determined as the number of days from the first patient-physician consultation with symptoms until the pathologically confirmed date of diagnosis. Total Treatment Interval (TTI) was calculated until the first day of any form of treatment. Statistical analyses, descriptive analysis and analysis of variance, were performed.

RESULTS

A minority (36.8%) of the diagnosed CRC cases were early stage cancers (Stages I-II), while the majority (59.9%) of the cases were diagnosed as advanced stage (Stages III-IV) cancers. The median TDI was 41 days, and the median TTI was 67 days. There was a wide range between minimum and maximum waiting times regarding both diagnosis and initiation of therapy (369-371 days).

CONCLUSIONS

Wait times to diagnosis and treatment of CRC in Hungary are similar to Western countries however the ratio of advanced cancers at diagnosis is higher. The cause of late diagnosis may be due to patient delay, indicating the need for implementation of primary and secondary prevention.

Endoscopic resection techniques for colorectal neoplasia: Current developments

Endoscopic polypectomy and endoscopic mucosal resection (EMR) are the established treatment standards for colorectal polyps. Current research aims at the reduction of both complication and recurrence rates as well as on shortening procedure times. Cold snare resection is the emerging standard for the treatment of smaller (< 5mm) polyps and is possibly also suitable for the removal of non-cancerous polyps up to 9 mm. The method avoids thermal damage, has reduced procedure times and probably also a lower risk for delayed bleeding. On the other end of the treatment spectrum, endoscopic submucosal dissection (ESD) offers en bloc resection of larger flat or sessile lesions. The technique has obvious advantages in the treatment of high-grade dysplasia and early cancer. Due to its minimal recurrence rate, it may also be an alternative to fractionated EMR of larger flat or sessile lesions. However, ESD is technically demanding and burdened by longer procedure times and higher costs. It should therefore be restricted to lesions suspicious for high-grade dysplasia or early invasive cancer. The latest addition to endoscopic resection techniques is endoscopic full-thickness resection with specifically developed devices for flexible endoscopy. This method is very useful for the treatment of smaller difficult-to-resect lesions, e.g., recurrence with scar formation after previous endoscopic resections.

Combination of Different Fecal Immunochemical Tests in Colorectal Cancer Screening: Any Gain in Diagnostic Performance?

A variety of fecal immunochemical tests (FITs) are used for colorectal cancer screening. FIT performance could be improved further. It is unclear, whether the combination of different FITs with different analytical characteristics (such as, different antibodies for the detection of fecal hemoglobin) can yield a better diagnostic performance. Fecal samples were obtained from 2042 participants of screening colonoscopy. All participants with advanced neoplasm (AN, colorectal cancer (n = 16) or advanced adenoma (n = 200)) and 300 randomly selected participants without AN were included. Nine quantitative FITs were evaluated simultaneously. Sensitivity and specificity was calculated for single tests (n = 9) and for their pairwise test combinations (n = 36) (requiring either both FITs (P++) or at least one FIT (P+) to be positive for defining a positive test result). Mean age of the participants (n = 516) was 63 (range: 50–79) years and 56% were men. At cutoffs yielding a specificity of 96.7% for single FITs, the median gain in specificity by P++ combination was +1.0%, whereas the median loss in sensitivity for AN was −4.2%. For P+ combination the median gain in sensitivity for AN was +2.8%, at a prize of median loss of −1.0% of specificity. Combinations of different FITs do not yield any relevant gain in diagnostic performance.

Colorectal cancer: evolution of screening strategies

Background and aim

Colorectal cancer is considered to be a major public health problem. It is the third most frequent cancer at a global level and also the fourth most frequent cause of death. Previous scientific findings have proved that a significant percentage of colorectal cancer deaths are due to the abscence of screening. The aim of this review is to present the evolution of the screening strategies by using the most recommended and recent colorectal cancer screening guidelines.

Methods

A systematic literature search on the scientific databases was performed, identifying some of the most important colorectal cancer screening guidelines publications.

Results

The most recent guidelines of American Cancer Society (2018) recommend that adults aged 45 years and older with an average risk of colorectal cancer should undergo regular screening. All the guidelines have considered fecal occult blood testing (annual or biennial), fecal immunochemical test (annual), flexible sigmoidoscopy (every 5 years) and colonoscopy (every 10 years) as the most preferred screening options. However, there are discrepancies with regards to which tests should be preferred for screening.

Conclusion

Increased compliance with colorectal cancer screening recommendations has the potential to improve patients’ health and to reduce colorectal cancer morbidity and mortality rates. It is important for health care providers to have an understanding of the risk factors for colorectal cancer and various stages of disease development in order to recommend appropriate screening strategies.

Findings during screening colonoscopies in a Middle Eastern cohort

BACKGROUND/AIMS

Colorectal cancer is the most common cancer in males and the third most common cancer in females. We aim to determine the polyp and adenoma prevalence in a cohort of patients who underwent opportunistic screening colonoscopies.

PATIENTS AND METHODS

A retrospective cohort study was conducted using an endoscopic reporting database of individuals seen at three tertiary care hospitals (two public hospitals and one private) in Riyadh, Saudi Arabia. Consecutive patients who were 45 years of age and older and underwent opportunistic screening colonoscopies between November 2016 and October 2017 were included. We excluded those with a history of colon cancer or colonic resection for any reason, inflammatory bowel disease, gastrointestinal bleeding, or anemia.

RESULTS

Around 1180 patients were included in the study with a mean age of 58.6 years (SD = 7.3), with males representing 53.6% and an overall cecal intubation rate of 92.4%. Masses were found in 1.6% of the study population (50% in the sigmoid or rectosigmoid, 37.5% in the rectum). The polyp detection rate in colonoscopies was 24.8% and the adenoma detection rate was 16.8%. The histology of removed polyps was tubular adenomas in 56.6%, hyperplastic polyps in 32.7%, tubulovillous adenomas in 8.2%, and villous adenomas in 2.5%. The majority of the polyps were in the sigmoid colon (28.3%) and rectum (22.0%), followed by the ascending colon (11.2%) and cecum (10.3%), then the transverse colon and descending colon (9.4% each), and multiple locations in the remainder.

CONCLUSION

The prevalence of polyps and adenomas in this cohort is less than that reported in the Western populations.

The gap between knowledge and undergoing colorectal cancer screening using the Health Belief Model: A national survey

BACKGROUND/AIMS

Colorectal cancer (CRC) is a public health issue, and before the initiation of a national cancer screening program, there is a need to examine the acceptance of the public to undergo CRC screening and explore potential barriers.

MATERIALS AND METHODS

A nationwide survey was conducted using an electronic platform to collect demographic variables and using the Health Belief Model to assess attitudes and behavior of participants as well as the knowledge about and intent to undergo CRC screening. At the end of the survey, participants from Riyadh were invited to get screened for CRC.

RESULTS

Responses from 5720 individuals covering all the 13 jurisdictions of Saudi Arabia were collected. Males represented 71.53% of the respondents; the mean age was 43.28 years and 15.24% had already undergone CRC screening using various methods, mostly colonoscopy (72.73%). The mean knowledge score was 11.05 (standard deviation 4.4, range 1-23), with no difference between genders, jurisdictions of the Kingdom, between those who expressed interest in screening and those who did not, and between those who accepted the invitation to undergo CRC screening and those who did not. Participants displayed positive attitudes toward both CRC screening and colonoscopy as a screening tool, and 73% expressed willingness to undergo screening. On multivariate analysis, male gender was the only factor associated with a higher probability of accepting screening, whereas neither knowledge nor willingness to undergo screening predicted accepting the invitation to screening.

CONCLUSION

Although the majority of participants were willing to undergo screening, no significant correlation between knowledge and willingness to undergo screening were predictors of screening uptake. Other areas that could be targeted in the promotion of CRC screening uptake to bridge the gap between "knowing" and "doing" should be explored.

Gelatin-based hydrogels as potential biomaterials for colonic delivery of oxaliplatin

In present investigation, gelatin-based (AA-co-AMPS) hydrogels were prepared using N, N'-Methylenebisacrylamide (MBA) as a cross-linker and ammonium per sulfate (APS) as an initiator. The successful crosslinking and network formation was confirmed by Fourier transform infrared spectroscopy (FT IR). Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) investigations proved the higher thermal stability and successful entrapment of oxaliplatin (OXP) in the polymeric network. X-ray diffraction (XRD) confirmed the loss in crystallinity of the drug after loading in the hydrogel. Scanning electron microscopy (SEM) revealed the porous surface of the hydrogel. The newly formed hydrogels were responsive to change in pH. The swelling, drug loading and drug release was increased with increase in concentration of acrylic acid (AA) while gelatin and 2-acrylamido 2-methylpronesulfonic acid (AMPS) were found to act inversely. The in-vitro enzymatic degradation study showed that the blank hydrogels were more stable against the blank PBS than the collagenase and lysozyme. MTT-assay proved that the blank hydrogels were cyto-compatible while free OXP as well as OXP-loaded hydrogels showed dose dependent controlled cytotoxicity against Vero, MCF-7 and HCT-116 cell lines. The preliminary safety evaluation and oral tolerability showed that the hydrogel suspension was biocompatible and well tolerable upto 4000 mg/kg of body weight without causing any hematological or histopathological changes in rabbits.

Facile Synthesis of Chitosan Based-(AMPS-co-AA) Semi-IPNs as a Potential Drug Carrier: Enzymatic Degradation, Cytotoxicity, and Preliminary Safety Evaluation

OBJECTIVE

The study describes the development of chitosan-based (AMPS-co-AA) semi-IPN hydrogels using free radical polymerization technique.

METHODS

The resulting hydrogels were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), X-Ray diffraction (XRD), and Scanning Electron Microscopy (SEM). The successful crosslinking of chitosan, 2- Acrylamido-2-Methylpropane Sulfonic Acid (AMPS), and Acrylic Acid (AA) was confirmed by FT IR. Unloaded and drug-loaded hydrogels exhibited higher thermal stability after crosslinking compared to the individual components. XRD confirmed the decrease in crystallinity after hydrogel formation and molecular dispersion of Oxaliplatin (OXP) in the polymeric network. SEM showed rough, vague and nebulous surface resulting from crosslinking and loading of OXP.

RESULTS

The experimental results revealed that swelling and drug release were influenced by the pH of the medium being low at acidic pH and higher at basic pH. Increasing the concentration of chitosan and AA enhanced the swelling, drug loading and drug release while AMPS was found to act inversely.

CONCLUSION

It was confirmed that the hydrogels were degraded more by specific enzyme lysozyme as compared to the non-specific enzyme collagenase. In-vitro cytotoxicity suggested that the unloaded hydrogels were non-cytotoxic while crude drug and drug-loaded hydrogel exhibited dose-dependent cytotoxicity against HCT-116 and MCF-7. Results of acute oral toxicity on rabbits demonstrated that the hydrogels are non-toxic up to 3900 mg/kg after oral administration, as no toxicity or histopathological changes were observed in comparison to control rabbits. These pH-sensitive hydrogels appear to provide an ideal basis as a safe carrier for oral drug delivery.

The burden of cancers and their variations across the states of India: the Global Burden of Disease Study 1990-2016

Background

Previous efforts to report estimates of cancer incidence and mortality in India and its different parts include the National Cancer Registry Programme Reports, Sample Registration System cause of death findings, Cancer Incidence in Five Continents Series, and GLOBOCAN. We present a comprehensive picture of the patterns and time trends of the burden of total cancer and specific cancer types in each state of India estimated as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 because such a systematic compilation is not readily available.

Methods

We used all accessible data from multiple sources, including 42 population-based cancer registries and the nationwide Sample Registration System of India, to estimate the incidence of 28 types of cancer in every state of India from 1990 to 2016 and the deaths and disability-adjusted life-years (DALYs) caused by them, as part of GBD 2016. We present incidence, DALYs, and death rates for all cancers together, and the trends of all types of cancers, highlighting the heterogeneity in the burden of specific types of cancers across the states of India. We also present the contribution of major risk factors to cancer DALYs in India.

Findings

8·3% (95% uncertainty interval [UI] 7·9–8·6) of the total deaths and 5·0% (4·6–5·5) of the total DALYs in India in 2016 were due to cancer, which was double the contribution of cancer in 1990. However, the age-standardised incidence rate of cancer did not change substantially during this period. The age-standardised cancer DALY rate had a 2·6 times variation across the states of India in 2016. The ten cancers responsible for the highest proportion of cancer DALYs in India in 2016 were stomach (9·0% of the total cancer DALYs), breast (8·2%), lung (7·5%), lip and oral cavity (7·2%), pharynx other than nasopharynx (6·8%), colon and rectum (5·8%), leukaemia (5·2%), cervical (5·2%), oesophageal (4·3%), and brain and nervous system (3·5%) cancer. Among these cancers, the age-standardised incidence rate of breast cancer increased significantly by 40·7% (95% UI 7·0–85·6) from 1990 to 2016, whereas it decreased for stomach (39·7%; 34·3–44·0), lip and oral cavity (6·4%; 0·4–18·6), cervical (39·7%; 26·5–57·3), and oesophageal cancer (31·2%; 27·9–34·9), and leukaemia (16·1%; 4·3–24·2). We found substantial inter-state heterogeneity in the age-standardised incidence rate of the different types of cancers in 2016, with a 3·3 times to 11·6 times variation for the four most frequent cancers (lip and oral, breast, lung, and stomach). Tobacco use was the leading risk factor for cancers in India to which the highest proportion (10·9%) of cancer DALYs could be attributed in 2016.

Interpretation

The substantial heterogeneity in the state-level incidence rate and health loss trends of the different types of cancer in India over this 26-year period should be taken into account to strengthen infrastructure and human resources for cancer prevention and control at both the national and state levels. These efforts should focus on the ten cancers contributing the highest DALYs in India, including cancers of the stomach, lung, pharynx other than nasopharynx, colon and rectum, leukaemia, oesophageal, and brain and nervous system, in addition to breast, lip and oral cavity, and cervical cancer, which are currently the focus of screening and early detection programmes.

Funding

Bill & Melinda Gates Foundation; and Indian Council of Medical Research, Department of Health Research, Ministry of Health and Family Welfare, Government of India.

Correlations between CD34 Immunolabelled Blood Vessels and CD34 mRNA Expression in Colorectal Cancer

Purpose: This study aims to determine the correlation between microvessel density of CD34 immunolabelled blood vessels and CD34 mRNA gene expression in colorectal cancer tissue. Material/Methods: Standard immunohistochemistry and gene expression was perform on samples collected from 76 patients with colorectal cancer in order to determinate the number of CD34 immunolabelled blood vessels and the relative quantity of CD34 mRNA. Results: For the study group, the mean CD34 immunolabelled microvascular density (MVD) was of 307/mm², and the mean CD34 gene expression value for colon cancer was 2.303. The low p value (<0.001) of the Spearman correlation test showed a significant direct correlation between CD34 MVD and CD34 gene expression for the entire study group. Conclusions: CD34 gene`s expression can be looked at as a prognostic factor in colorectal cancer.