Colorectal cancer screening in average risk individuals

Lifetime prevalence and correlates of colorectal cancer screening among low-income U.S. Veterans

PURPOSE

The Veterans Health Administration (VHA) is the largest integrated healthcare system in the U.S. While preventive healthcare services are high priority in the VHA, low-income U.S. Veterans experience adverse life circumstances that may negatively impact their access to these services. This study examined lifetime prevalence as well as demographic, socioeconomic, military-specific, and clinical correlates of colorectal cancer (CRC) screening among low-income U.S. Veterans ≥ 50 years of age.

METHODS

Cross-sectional data on 862 participants were analyzed from the 2021-2022 National Veteran Homeless and Other Poverty Experiences study.

RESULTS

Overall, 55.3% (95% confidence interval [CI] 51.3-59.3%) reported ever-receiving CRC-screening services. In a multivariable logistic regression model, never-receivers of CRC screening were twice as likely to reside outside of the Northeast, and more likely to be married (odds ratio [OR] = 1.86, 95% CI 1.02, 3.37), have BMI < 25 kg/m2 [vs. 25- < 30 kg/m2] (OR = 1.75, 95% CI 1.19, 2.58), or ≥ 1 chronic condition (OR = 1.46, 95% CI 1.06, 2.02). Never-receivers of CRC screening were less likely to be female (OR = 0.53, 95% CI 0.29, 0.96), aged 65-79y [vs. ≥ 80y] (OR = 0.61, 95% CI 0.40, 0.92), live in 5 + member households (OR = 0.33, 95% CI 0.13, 0.86), disabled (OR = 0.45, 0.22, 0.92), with purchased health insurance (OR = 0.56, 95% CI 0.33, 0.98), or report alcohol-use disorder (OR = 0.10, 95% CI 0.02, 0.49) and/or HIV/AIDS (OR = 0.28, 95% CI 0.12, 0.68).

CONCLUSION

Nearly 55% of low-income U.S. Veterans reported ever screening for CRC. Variations in CRC-screening behaviors according to veteran characteristics highlight potential disparities as well as opportunities for targeted behavioral interventions.

A Case of Sporadic Multiple Colonic Polyps in a Young Woman

Sporadic colorectal cancer arises from an adenoma. As mutations in the adenomatous polyposis coli (APC) tumor suppressor gene have been frequently detected in colorectal adenomas, the APC gene is considered a gatekeeper in colorectal carcinogenesis. Here, we report a case of sporadic multiple colonic adenomas that were accompanied by an APC-truncating mutation. A 25-year-old Korean woman presented with dozens of incidentally found colonic polyps. There was no family history of colorectal polyposis or colon cancer in her first or second-degree relatives. All the polyps were removed endoscopically at once, and their pathological examination revealed tubular adenoma. Mutational analysis showed a 2-bp deletion mutation at codon 443, which generates a premature stop codon at codon 461 of the APC gene, and Western blot analysis demonstrated both wild-type and truncated APC proteins in adenoma tissue. This study suggests that a single truncating mutation of the APC gene may initiate adenoma formation.

Trends and Predictors for the Uptake of Colon Cancer Screening Using the Fecal Occult Blood Test in Spain from 2011 to 2017

Background: In Spain, colorectal cancer screening using the fecal occult blood test, targeted towards the 50–69 age bracket, was implemented on different dates. We aim to assess the temporal trend of colorectal cancer (CRC) screening uptake according to the year of screening implementation in each region and to identify predictors for the uptake of CRC screening. Methods: A cross-sectional study with 12,657 participants from the Spanish National Health Surveys 2011 and 2017 was used. Uptake rates were analyzed according to the date that the screening program was implemented. Results: For regions with programs implemented before 2011, the uptake rate increased 3.34-fold from 2011 to 2017 (9.8% vs. 32.7%; p < 0.001). For regions that implemented screening within the 2011–2016 period, the uptake rose from 4.3% to 13.2% (3.07-fold; p < 0.001), and for regions that implemented screening after 2016, the uptake increased from 3.4% to 8.8% (2.59-fold; p < 0.001). For the entire Spanish population, the uptake increased 3.21-fold (6.8% vs. 21.8%; p < 0.001). Positive predictors for uptake were older age, Spanish nationality, middle-to-high educational level, suffering chronic diseases, non-smoking and living in regions where screening programs were implemented earlier. Conclusions: The different periods for the implementation of CRC screening as well as sociodemographic and health inequalities may have limited the improvement in the screening uptake from 2011 to 2017 in Spain.

Diagnostic Value of Methylated Septin9 for Colorectal Cancer Screening: A Meta-Analysis

Background

Septin9 is a member of GTP-binding protein family, and is used as a predictive diagnostic index. However, it has not been widely adopted due to inconsistent results reported in the literature. The present study was performed to determine the diagnostic accuracy of methylated Septin9 (mSEPT9) for colorectal cancer (CRC) and to evaluate its utility in CRC screening.

Material/Methods

After reviewing relevant studies, accuracy measures (pooled sensitivity and specificity, positive/negative likelihood ratio [PLR/NLR], and diagnostic odds ratio [DOR]) were calculated for mSEPT9 in the diagnosis of CRC. Overall test performance was summarized using summary receiver operating characteristic curve analysis. Potential between-study heterogeneity was explored by use of a meta-regression model. We divided included studies into Epi proColon test and non-Epi proColon test subgroups. We compared the effects of mSEPT9 and fecal occult blood test (FOBT) for CRC screening.

Results

A total of 9870 subjects in 14 studies were recruited. Pooled sensitivity and specificity, PLR, NLR, DOR, and corresponding 95% confidence intervals (CI) of mSEPT9 for CRC diagnosis were 0.66 (95% CI: 0.64–0.69), 0.91 (95% CI: 0.90–0.91), 5.59 (95% CI: 4.03–7.74), 0.37 (95% CI: 0.29–0.48), and 16.79 (95% CI: 10.54–26.76), respectively. The area under the summary ROC curve (AUC) was 0.8563. The AUCs in the Epi proColon test and non-Epi proColon test for CRC diagnosis were 0.8709 and 0.7968, respectively. In head-to-head comparison, AUC of mSEPT9 and FOBT for CRC diagnosis were 0.7857 and 0.6571, respectively.

Conclusions

The present study demonstrates that mSEPT9 can be a good diagnostic biomarker complementary to FOBT as a screening tool for CRC.

The Usefulness of a Novel Screening Kit for Colorectal Cancer Using the Immunochromatographic Fecal Tumor M2 Pyruvate Kinase Test

Background/Aims

M2 pyruvate kinase (M2-PK) is an enzyme that is produced in undifferentiated and proliferating tissues. This study aims to evaluate the usefulness of the immunochromatographic M2 pyruvate kinase (iM2-PK) for the screening of colorectal cancer (CRC) and premalignant lesions.

Methods

Healthy volunteers and patients with colorectal neoplasia were enrolled in six academic hospitals in the capital province of Korea. The iM2-PK value was compared with the immunochromatographic fecal occult blood test (iFOBT) and fecal tumor M2-PK enzyme-linked immunosorbent assay (ELISA).

Results

A total of 323 subjects were enrolled. The sensitivity of iM2-PK for CRC was 92.8%, which was superior to iFOBT (47.5%, p<0.0001). For adenomatous lesions, the sensitivity of iM2-PK was 69.4%, which was also superior to iFOBT (12.1%, p<0.001). Compared with M2-PK ELISA, iM2-PK exhibited significantly enhanced sensitivity for CRC (97.5% vs 80.0%, p=0.0289). The sensitivity of iM2-PK was higher in advanced stages of CRC compared with cancers confined to the mucosa and submucosa (p<0.05). However, lymph node metastasis had no influence on the sensitivity of iM2-PK.

Conclusions

The iM2-PK exhibited increased sensitivity for identifying CRC and adenomatous lesions compared with iFOBT. Given its rapid results and convenience, CRC screening using iM2-PK is promising.

Quantitative proteomic analysis of paired colorectal cancer and non-tumorigenic tissues reveals signature proteins and perturbed pathways involved in CRC progression and metastasis

Modern proteomics has proven instrumental in our understanding of the molecular deregulations associated with the development and progression of cancer. Herein, we profile membrane-enriched proteome of tumor and adjacent normal tissues from eight CRC patients using label-free nanoLC-MS/MS-based quantitative proteomics and advanced pathway analysis. Of the 948 identified proteins, 184 proteins were differentially expressed (P<0.05, fold change>1.5) between the tumor and non-tumor tissue (69 up-regulated and 115 down-regulated in tumor tissues). The CRC tumor and non-tumor tissues clustered tightly in separate groups using hierarchical cluster analysis of the differentially expressed proteins, indicating a strong CRC-association of this proteome subset. Specifically, cancer associated proteins such as FN1, TNC, DEFA1, ITGB2, MLEC, CDH17, EZR and pathways including actin cytoskeleton and RhoGDI signaling were deregulated. Stage-specific proteome signatures were identified including up-regulated ribosomal proteins and down-regulated annexin proteins in early stage CRC. Finally, EGFR(+) CRC tissues showed an EGFR-dependent down-regulation of cell adhesion molecules, relative to EGFR(-) tissues. Taken together, this study provides a detailed map of the altered proteome and associated protein pathways in CRC, which enhances our mechanistic understanding of CRC biology and opens avenues for a knowledge-driven search for candidate CRC protein markers.

Efficacy of communication skills training on colorectal cancer screening by GPs: a cluster randomised controlled trial

Colorectal cancer (CRC) mass screening has been implemented in France since 2008. Participation rates remain too low. The objective of this study was to test if the implementation of a training course focused on communication skills among general practitioners (GP) would increase the delivery of gaiac faecal occult blood test and CRC screening participation among the target population of each participating GP. A cluster randomised controlled trial was conducted with GP's practice as a cluster unit. GPs from practices in the control group were asked to continue their usual care. GPs of the intervention group received a 4-h educational training, built with previous qualitative data on CRC screening focusing on doctor-patient communication with a follow-up of 7 months for both groups. The primary outcome measure was the patients' participation rate in the target population for each GP. Seventeen GPs (16 practices) in intervention group and 28 GPs (19 practices) in control group participated. The patients' participation rate in the intervention group were 36.7% vs. 24.5% in the control group (P = 0.03). Doctor-patient communication should be developed and appear to be one of the possible targets of improvement patients adherence and participation rate in the target population for CRC mass screening.

Genomics and epigenomics of colorectal cancer

Colorectal cancer is one of the most common cancer types worldwide and accounts for approximately 600,000 deaths annually. Work over the last decades has uncovered a number of tumor-suppressor and oncogenes which are frequently mutated and might thus be responsible for the malignant transformation. However, only with the development of new high-throughput technologies systematic analyses of the genome and epigenomes became feasible. While data generation has increased exponential, we are now faced with new challenges to transform these data into useful models that help predicting the outcome of genomic aberrations and to develop novel diagnostic and therapeutic strategies. As a basis for the modeling it is essential to understand and integrate current knowledge. We review previous and current ideas in colorectal cancer development and focus on a pathway oriented view. We show that colorectal cancer is a multilayer complex disease affecting the genome as well as the epigenome with direct consequences on the gene and microRNA (miRNA) expression signatures. The goal is to illustrate the current principles of colorectal cancer pathogenesis and to illustrate the need for elaborate computer modeling systems.

[Adherence to a population-based colorectal cancer screening program in Catalonia (Spain), 2000-2008]

OBJECTIVE

To analyze correlates of adherence to colorectal cancer screening with biennial fecal occult blood testing in asymptomatic individuals aged 50 to 69 years.

METHODS

A cross-sectional telephone survey was conducted among people (n = 1,193) invited to participate in at least two successive rounds of a population-based colorectal cancer screening program in L'Hospitalet de Llobregat (Barcelona, Spain). Subjects were classified according to their adherence to colorectal cancer screening guidelines (non-adherent, irregular adherent and totally adherent). Independent variables were sociodemographic variables, self-perceived health, attitudes and beliefs regarding colorectal cancer and preventive activities. Binary and politomous logistic regression models were performed.

RESULTS

Of the individuals invited to participate in the screening program, 14.4% were adherent to screening recommendations and 18.4% were occasionally adherent. Significant differences were found in beliefs and attitudes regarding colorectal cancer and its early detection among adherent and non-adherent individuals. Sharing the decision to participate in screening with a family member increased adherence by nine- and tweve-fold. A positive perception of the screening process was a facilitator to adherence.

CONCLUSIONS

Attitudes and beliefs regarding colorectal cancer and its early detection, as well as familial support, are associated with initial participation in colorectal cancer screening but do not affect the persistence of preventive behavior over time.

Proximal fluid proteome profiling of mouse colon tumors reveals biomarkers for early diagnosis of human colorectal cancer

PURPOSE

Early detection of colorectal cancer (CRC) and its precursor lesions is an effective approach to reduce CRC mortality rates. This study aimed to identify novel protein biomarkers for the early diagnosis of CRC.

EXPERIMENTAL DESIGN

Proximal fluids are a rich source of candidate biomarkers as they contain high concentrations of tissue-derived proteins. The FabplCre;Apc(15lox/+) mouse model represents early-stage development of human sporadic CRC. Proximal fluids were collected from normal colon and colon tumors and subjected to in-depth proteome profiling by tandem mass spectrometry. Carcinoembryonic antigen (CEA) and CHI3L1 human serum protein levels were determined by ELISA.

RESULTS

Of the 2,172 proteins identified, quantitative comparison revealed 192 proteins that were significantly (P < 0.05) and abundantly (>5-fold) more excreted by tumors than by controls. Further selection for biomarkers with highest specificity and sensitivity yielded 52 candidates, including S100A9, MCM4, and four other proteins that have been proposed as candidate biomarkers for human CRC screening or surveillance, supporting the validity of our approach. For CHI3L1, we verified that protein levels were significantly increased in sera from patients with adenomas and advanced adenomas compared with control individuals, in contrast to the CRC biomarker CEA.

CONCLUSION

These data show that proximal fluid proteome profiling with a mouse tumor model is a powerful approach to identify candidate biomarkers for early diagnosis of human cancer, exemplified by increased CHI3L1 protein levels in sera from patients with CRC precursor lesions.

A quantitative proteomic approach of the different stages of colorectal cancer establishes OLFM4 as a new nonmetastatic tumor marker

Expression profiles represent new molecular tools that are useful to characterize the successive steps of tumor progression and the prediction of recurrence or chemotherapy response. In this study, we have used quantitative proteomic analysis to compare different stages of colorectal cancer. A combination of laser microdissection, OFFGEL separation, iTRAQ labeling, and MALDI-TOF/TOF MS was used to explore the proteome of 28 colorectal cancer tissues. Two software packages were used for identification and quantification of differentially expressed proteins: Protein Pilot and iQuantitator. Based on ∼1,190,702 MS/MS spectra, a total of 3138 proteins were identified, which represents the largest database of colorectal cancer realized to date and demonstrates the value of our quantitative proteomic approach. In this way, individual protein expression and variation have been identified for each patient and for each colorectal dysplasia and cancer stage (stages I-IV). A total of 555 proteins presenting a significant fold change were quantified in the different stages, and this differential expression correlated with immunohistochemistry results reported in the Human Protein Atlas database. To identify a candidate biomarker of the early stages of colorectal cancer, we focused our study on secreted proteins. In this way, we identified olfactomedin-4, which was overexpressed in adenomas and in early stages of colorectal tumors. This early stage overexpression was confirmed by immunohistochemistry in 126 paraffin-embedded tissues. Our results also indicate that OLFM4 is regulated by the Ras-NF-κB2 pathway, one of the main oncogenic pathways deregulated in colorectal tumors.

Potential of soluble CD26 as a serum marker for colorectal cancer detection

Colorectal cancer is characterized by a low survival rate even though the basis for colon cancer development, which involves the evolution of adenomas to carcinoma, is known. Moreover, the mortality rates continue to rise in economically transitioning countries although there is the opportunity to intervene in the natural history of the adenoma–cancer sequence through risk factors, screening, and treatment. Screening in particular accounted for most of the decline in colorectal cancer mortality achieved in the USA during the period 1975-2000. Patients show a better prognosis when the neoplasm is diagnosed early. Among the variety of screening strategies, the methods range from invasive and costly procedures such as colonoscopy to more low-cost and non-invasive tests such as the fecal occult blood test (guaiac and immunochemical). As a non-invasive biological serum marker would be of great benefit because of the performance of the test, several biomarkers, including cytologic assays, DNA and mRNA, and soluble proteins, have been studied. We found that the soluble CD26 (sCD26) concentration is diminished in serum of colorectal cancer patients compared to healthy donors, suggesting the potential utility of a sCD26 immunochemical detection test for early diagnosis. sCD26 originates from plasma membrane CD26 lacking its transmembrane and cytoplasmic domains. Some 90%–95% of sCD26 has been associated with serum dipeptidyl peptidase IV (DPP-IV) activity. DPP-IV, assigned to the CD26 cluster, is a pleiotropic enzyme expressed mainly on epithelial cells and lymphocytes. Our studies intended to validate this test for population screening to detect colorectal cancer and advanced adenomas are reviewed here.

Use of faecal markers in screening for colorectal neoplasia: a European group on tumor markers position paper

Several randomized controlled trials have shown that population-based screening using faecal occult blood testing (FOBT) can reduce mortality from colorectal neoplasia. Based on this evidence, a number of countries have introduced screening for colorectal cancer (CRC) and high-risk adenoma and many others are considering its introduction. The aim of this article is to critically review the current status of faecal markers as population-based screening tests for these neoplasia. Most of the available faecal tests involve the measurement of either occult blood or a panel of DNA markers. Occult blood may be measured using either the guaiac faecal occult blood test (gFOBT) or a faecal immunochemical test (iFOBT). Although iFOBT may require a greater initial investment, they have several advantages over gFOBT, including greater analytical sensitivity and specificity. Their use results in improved clinical performance and higher uptake rates. Importantly for population screening, some of the iFOBTs can be automated and provide an adjustable cutoff for faecal haemoglobin concentration. However, samples for iFOBT, may be less stable after collection than for gFOBT. For new centres undertaking FOBT for colorectal neoplasia, the European Group on Tumour Markers recommends use of a quantitative iFOBT with an adjustable cutoff point and high throughput analysis. All participants with positive FOBT results should be offered colonoscopy. The panel recommends further research into increasing the stability of iFOBT and the development of improved and affordable DNA and proteomic-based tests, which reduce current false negative rates, simplify sample transport and enable automated analysis.

Biomarkers for colorectal cancer

Colorectal cancer (CRC) is the third most common epithelial malignancy in the world. Since CRC develops slowly from removable precancerous lesions, detection of the lesion at an early stage by regular health examinations can reduce the incidence and mortality of this malignancy. Colonoscopy significantly improves the detection rate of CRC, but the examination is expensive and inconvenient. Therefore, we need novel biomarkers that are non-invasive to enable us to detect CRC quite early. A number of validation studies have been conducted to evaluate genetic, epigenetic or protein markers for identification in the stool and/or serum. Currently, the fecal occult blood test is the most widely used method of screening for CRC. However, advances in genomics and proteomics will lead to the discovery of novel non-invasive biomarkers.

DNA methylation markers in colorectal cancer

Colorectal cancer (CRC) arises as a consequence of the accumulation of genetic and epigenetic alterations in colonic epithelial cells during neoplastic transformation. Epigenetic modifications, particularly DNA methylation in selected gene promoters, are recognized as common molecular alterations in human tumors. Substantial efforts have been made to determine the cause and role of aberrant DNA methylation ("epigenomic instability") in colon carcinogenesis. In the colon, aberrant DNA methylation arises in tumor-adjacent, normal-appearing mucosa. Aberrant methylation also contributes to later stages of colon carcinogenesis through simultaneous methylation in key specific genes that alter specific oncogenic pathways. Hypermethylation of several gene clusters has been termed CpG island methylator phenotype and appears to define a subgroup of colon cancer distinctly characterized by pathological, clinical, and molecular features. DNA methylation of multiple promoters may serve as a biomarker for early detection in stool and blood DNA and as a tool for monitoring patients with CRC. DNA methylation patterns may also be predictors of metastatic or aggressive CRC. Therefore, the aim of this review is to understand DNA methylation as a driving force in colorectal neoplasia and its emerging value as a molecular marker in the clinic.

[Colonoscopic findings in asymptomatic people]

CONTEXT

Colorectal cancer is the second leading cause of cancer-related death. Prevention of colorectal cancer should be achievable by screening programs in asymptomatic patients.

OBJECTIVE

To assess the colonoscopic findings in asymptomatic people submitted to screening.

METHODS

A prospective study was undertaken on 153 consecutive asymptomatic people submitted to colonoscopy. Sex, age, previous diseases and familial cases of cancer, as well as tobacco and alcohol ingestion were assessed. Patients with rectal macro- or microscopic bleeding and colorectal diseases were excluded. Bowel preparation, polyps, angioectasias, diverticular disease, inflammation and neoplasm were also verified. Polyps were classified according to their size, number and location.

RESULTS

Mean age was 52.5 +/- 11.7 years. Family history for colorectal cancer occurred in 79.8% of individuals. Colonoscopic alterations were detected in 99 individuals: polyps in 64.3%, diverticular disease in 27.9%, inflammatory mucosal alterations in 9.7%, melanosi coli in 2.6% and angioectasias in 7.8%. There were an increasing incidence of polyps in patients older than 50 year. Multivariate logistic regression showed age and sex as predictive factors for polyps (OR = 1.43; 1.19 <OR <2.67).

CONCLUSION

There is a significant incidence of colonoscopic alterations in asymptomatic people submitted to colonoscopy for colorectal cancer screening.

Noninvasive molecular biomarkers for the detection of colorectal cancer

Colorectal cancer (CRC) is the third most common malignancy in the world. Because CRC develops slowly from removable precancerous lesions, detection of the disease at an early stage during regular health examinations can reduce both the incidence and mortality of the disease. Although sigmoidoscopy offers significant improvements in the detection rate of CRC, its diagnostic value is limited by its high costs and inconvenience. Therefore, there is a compelling need for the identification of noninvasive biomarkers that can enable earlier detection of CRC. Accordingly, many validation studies have been conducted to evaluate genetic, epigenetic or protein markers that can be detected in the stool or in serum. Currently, the fecal-occult blood test is the most widely used method of screening for CRC. However, advances in genomics and proteomics combined with developments in other relevant fields will lead to the discovery of novel non invasive biomarkers whose usefulness will be tested in larger validation studies. Here, noninvasive molecular biomarkers that are currently used in clinical settings and have the potential for use as CRC biomarkers are discussed.

Decreased expression of histamine H1 and H4 receptors suggests disturbance of local regulation in human colorectal tumours by histamine

Production of histamine in colon tumours has been described earlier. Histamine-mediated signals have been shown to be implicated in tumour growth, and the effects of histamine are largely determined locally by the histamine receptor expression pattern. We analysed histamine receptor expression in human colorectal cancer, adenoma and normal mucosa by quantitative reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis and immunostaining. Real-time RT-PCR results revealed significantly decreased (p<0.001) H1R and H4R mRNA levels in tumours compared to normal colonic mucosa, without any significant change in H2R mRNA expression. H3R was absent in most samples; it was detected at low levels in 7.9% of the cases. Protein analysis showed a similar decrease in histamine receptor expression in carcinoma and adenoma compared to normal mucosa controls. Based on these results, we performed further Western blot analysis on Dukes-classified and -selected tumour samples. We found significantly decreased H4R levels in neoplastic samples compared to normal colonic tissue, but there was no significant correlation between histamine receptor expression profile and the Dukes stage of tumours. Immunohistochemical staining revealed expression patterns of H1R, H2R and H4R similar to those suggested by the mRNA and Western blot results. In the present study, we demonstrate that H1R, H2R and H4R are expressed in colon carcinoma and the adjacent normal mucosa. The results suggest a dramatic alteration in the distribution of histamine receptors in colon cancer. These findings raise the perspective of targeted pharmacological studies with selective histamine receptor antagonists or agonists in the therapy of colorectal tumours.

Predictors of colorectal cancer screening behaviors among average-risk older adults in the United States

OBJECTIVE

To critically evaluate recent studies that examined determinants of CRC screening behaviors among average-risk older adults (>or=50 years) in the United States.

METHODS

A PUBMED (1996-2006) search was conducted to identify recent articles that focused on predictors of CRC initiation and adherence to screening guidelines among average-risk older adults in the United States.

RESULTS

Frequently reported predictors of CRC screening behaviors include older age, male gender, marriage, higher education, higher income, White race, non-Hispanic ethnicity, smoking history, presence of chronic diseases, family history of CRC, usual source of care, physician recommendation, utilization of other preventive health services, and health insurance coverage. Psychosocial predictors of CRC screening adherence are mostly constructs from the Health Belief Model, the most prominent of which are perceived barriers to CRC screening.

CONCLUSIONS

Evidence suggests that CRC screening is a complex behavior with multiple influences including personal characteristics, health insurance coverage, and physician-patient communication. Health promotion activities should target both patients and physicians, while focusing on increasing awareness of and accessibility to CRC screening tests among average-risk older adults in the United States.

Tumour markers in colorectal cancer: European Group on Tumour Markers (EGTM) guidelines for clinical use

The aim of this article is to present updated guidelines for the use of serum, tissue and faecal markers in colorectal cancer (CRC). Lack of specificity and sensitivity preclude the use of all existing serum markers for the early detection of CRC. For patients with stage II or stage III CRC who may be candidates for either liver resection or systemic treatment should recurrence develop, CEA should be measured every 2-3 months for at least 3 years after diagnosis. Insufficient evidence exists to recommend routine use of tissue factors such as thymidylate synthase, microsatellite instability (MSI), p53, K-ras and deleted in colon cancer (DCC) for either determining prognosis or predicting response to therapy in patients with CRC. Microsatellite instability, however, may be used as a pre-screen for patients with suspected hereditary non-polyposis colorectal cancer. Faecal occult blood testing but not faecal DNA markers may be used to screen asymptomatic subjects 50 years or older for early CRC.

Natural Death in the Forensic Setting

Although unexpected natural deaths comprise a large proportion of the cases seen in the forensic setting, the investigation of these cases remains a unique challenge. Some cases are straightforward; however, others require special examination and dissections, as well as the use of special dissections and ancillary studies. For the forensic investigator to accurately assign a cause and manner of death, one must be aware of the differential diagnoses, common scenarios, and typical victim. The authors reviewed all forensic cases referred to the Forensic Section of the Medical University of South Carolina over a 15-year period from January 1989-December 2003. The number of natural deaths occurring in adults (age 18 years and older) was 6932, compared with the overall number of 13,227 cases. The natural deaths were then analyzed as to autopsy findings, cause of death, cardiac versus noncardiac, age, race, and gender. Current techniques, special dissections, and ancillary studies that can assist in the classification of these deaths in the forensic setting are reviewed.

Colorectal cancer screening: recommendations and guideline adherence by physicians from digestive endoscopy centers in the Lazio region, Italy

INTRODUCTION

Endoscopy plays a key role in colorectal cancer screening; at the beginning of a mass screening campaign, it is important for public health officials to assess physicians' attitudes and adherence to guidelines regarding colorectal cancer screening.

METHODS

In April 2004, a questionnaire was sent to all 80 digestive endoscopy centers in the Lazio region, identified by the annual census of the Italian Society of Digestive Endoscopy. The results were compared to those from a similar survey of general practitioners (GPs).

RESULTS

Seventy-one centers (89%) returned the questionnaire. Only 3% of physicians said they did not recommend any colorectal cancer screening test. Colonoscopy was perceived as the most effective screening test and was the most recommended (80%). Fecal occult blood test was recommended by 61% of physicians and flexosigmoidoscopy by 11%. Endoscopy centers' physicians recommend screening more than GPs (96.9% vs. 78.3%), while they have a similar level of over-recommending (50.8% vs. 47.2%). Almost 95% of endoscopy physicians properly recommended colonoscopy after positive FOBT.

CONCLUSIONS

Neither physicians at endoscopy centers nor GPs tend to follow screening guidelines. Screening programmes should not rely on a single medical specialist, but on interdisciplinary management of the disease to strengthen adherence to existing guidelines.