Lower gastrointestinal symptoms are not predictive of colorectal neoplasia in a faecal occult blood screen-positive population

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

If Colorectal cancer (CRC) is detected and treated early, the survival rate is high. This is one of the reasons that population-based screening programs for the early detection of CRC using the faecal immunochemical test (FIT) started worldwide. These programs compete with regular colonoscopy programs and increase the waiting time for symptomatic patients. However, the literature has shown that the correlation between intestinal complaints and the gain of colonoscopy is poor. The aim of this study is to assess the diagnostic utility of symptoms for the yield (CRC) of colonoscopy and to compare this with the diagnostic utility of FIT when offered to symptomatic patients. Methods: 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. Results: 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. Conclusion: 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 cancers and advanced adenomas in asymptomatic participants in colorectal cancer screening: a cross-sectional study

OBJECTIVES

To assess detection rates for colorectal cancer (CRC) and advanced adenomas in asymptomatic CRC screening participants and bowel symptoms in association with CRC and advanced adenoma.

DESIGN

Cross-sectional study.

SETTING

Two screening centres.

PARTICIPANTS

42 554 men and women, aged 50-74 years, participating in a randomised CRC screening trial. 36 059 participants underwent a sigmoidoscopy (and follow-up colonoscopy if positive sigmoidoscopy) and 6495 underwent a colonoscopy after a positive faecal immunochemical test (FIT).

PRIMARY AND SECONDARY OUTCOME MEASURES

Proportion of asymptomatic participants diagnosed with CRC or advanced adenomas. Prevalence of bowel symptoms (rectal bleeding, change in bowel habits, diarrhoea, constipation, bloating, alternating bowel habits, general symptoms, other bowel symptoms) recorded by the endoscopist and their association with CRC and advanced adenomas.

RESULTS

Among sigmoidoscopy participants, 7336 (20.3%) reported at least one symptom. 120 (60%) out of 200 individuals with screen-detected CRC and 1301 (76.5%) out of 1700 with advanced adenoma were asymptomatic. Rectal bleeding was associated with detection of CRC and advanced adenoma (OR 4.3, 95% CI 3.1 to 6.1 and 1.8, 95% CI 1.5 to 2.1, respectively), while change in bowel habits only with CRC detection (OR 3.8, 95% CI 2.4 to 6.1). Among the FIT positives, 2173 (33.5%) reported at least one symptom. Out of 299 individuals with screen-detected CRC and 1639 with advanced adenoma, 167 (55.9%) and 1 175 (71.7%) were asymptomatic, respectively. Detection of CRC was associated with rectal bleeding (OR 1.8, 95% CI 1.4 to 2.3), change in bowel habits (OR 2.2, 95% CI 1.4 to 3.5) and abdominal pain (OR 1.8, 95% CI 1.2 to 2.7).

CONCLUSIONS

Some bowel symptoms increased the likelihood of being diagnosed with CRC or advanced adenoma. However, the majority of individuals with these findings were asymptomatic. Asymptomatic individuals should be encouraged to participate in CRC screening.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov Identifier: NCT01538550.

Impact of colorectal cancer screening participation in remote northern Canada: A retrospective cohort study

BACKGROUND

Screening provides earlier colorectal cancer (CRC) detection and improves outcomes. It remains poorly understood if these benefits are realized with screening guidelines in remote northern populations of Canada where CRC rates are nearly twice the national average and access to colonoscopy is limited.

AIM

To evaluate the participation and impact of CRC screening guidelines in a remote northern population.

METHODS

This retrospective cohort study included residents of the Northwest Territories, a northern region of Canada, age 50-74 who underwent CRC screening by a fecal immunohistochemical test (FIT) between January 1, 2014 to March 30, 2019. To assess impact, individuals with a screen-detected CRC were compared to clinically-detected CRC cases for stage and location of CRC between 2014-2016. To assess participation, we conducted subgroup analyses of FIT positive individuals exploring the relationships between signs and symptoms of CRC at the time of screening, wait-times for colonoscopy, and screening outcomes. Two sample Welch t-test was used for normally distributed continuous variables, Mann-Whitney-Wilcoxon Tests for data without normal distribution, and Chi-square goodness of fit test for categorical variables. A P value of < 0.05 was considered to be statistically significant.

RESULTS

6817 fecal tests were completed, meaning an annual average screening rate of 25.04%, 843 (12.37%) were positive, 629 individuals underwent a follow-up colonoscopy, of which, 24.48% had advanced neoplasia (AN), 5.41% had CRC. There were no significant differences in stage, pathology, or location between screen-detected cancers and clinically-detected cancers. In assessing participation and screening outcomes, we observed 49.51% of individuals referred for colonoscopy after FIT were ineligible for CRC screening, most often due to signs and symptoms of CRC. Individuals were more likely to have AN if they had signs and symptoms of cancer at the time of screening, waited over 180 d for colonoscopy, or were indigenous [respectively, estimated RR 1.18 95%CI of RR (0.89-1.59)]; RR 1.523 (CI: 1.035, 2.240); RR 1.722 (CI: 1.165, 2.547)].

CONCLUSION

Screening did not facilitate early cancer detection but facilitated higher than anticipated AN detection. Signs and symptoms of CRC at screening, and long colonoscopy wait-times appear contributory.

The use of electronic healthcare records for colorectal cancer screening referral decisions and risk prediction model development

BACKGROUND

The database used for the NHS Bowel Cancer Screening Programme (BCSP) derives participant information from primary care records. Combining predictors with FOBTs has shown to improve referral decisions and accuracy. The richer data available from GP databases could be used to complement screening referral decisions by identifying those at greatest risk of colorectal cancer. We determined the availability of data for key predictors and whether this information could be used to inform more accurate screening referral decisions.

METHODS

An English BCSP cohort was derived using the electronic notifications received from the BCSP database to GP records. The cohort covered a period between 13th May 2009 to 17th January 2017. Completeness of variables and univariable associations were assessed. Risk prediction models were developed using Cox regression and multivariable fractional polynomials with backwards elimination. Optimism adjusted performance metrics were reported. The sensitivity and specificity of a combined approach using the negative FOBT model plus FOBT positive patients was determined using a probability equivalent to a 3% PPV NICE guidelines level.

RESULTS

292,059 participants aged 60-74 were derived for the BCSP screening cohort. A model including the screening test result had a C-statistic of 0.860, c-slope of 0.997, and R² of 0.597. A model developed for negative screening results only had a C-statistic of 0.597, c-slope of 0.940, and R² of 0.062. Risk predictors included in the models included; age, sex, alcohol consumption, IBS diagnosis, family history of gastrointestinal cancer, smoking status, previous negatives and whether a GP had ordered a blood test. For the combined screening approach, sensitivity increased slightly from 53.90% (FOBT only) to 58.82% but at the expense of an increased referral rate.

CONCLUSIONS

This research has identified several potential predictors for CRC in a BCSP population. A risk prediction model developed for BCSP FOBT negative patients was not clinically useful due to a low sensitivity and increased referral rate. The predictors identified in this study should be investigated in a refined algorithm combining the quantitative FIT result. Combining data from multiple sources enables fuller patient profiles using the primary care and screening database interface.

Differences in diagnostic activity in general practice and findings for individuals invited to the danish screening programme for colorectal cancer: a population-based cohort study

OBJECTIVE

To investigate the diagnostic activity in general practice and the cumulative incidence of colorectal cancer (CRC) in individuals invited to the Danish national screening programme for CRC.

DESIGN

A historical population-based cohort study.

SETTING

The Danish CRC screening programme and general practice.

SUBJECTS

The 376,198 individuals invited to the Danish CRC screening programme from 1 March to 31 December 2014.

MAIN OUTCOME MEASURES

The diagnostic activity (consultations and haemoglobin measures) in general practice in the year preceding the screening invitation and the cumulated incidence of CRC in the year following the screening invitation.

RESULTS

Screening participants had significantly higher diagnostic activity than non-participants. Individuals with a positive faecal immunochemical test (FIT) had higher diagnostic activity compared to individuals with a negative FIT, and a small increase in the months leading up to the invitation. Individuals with a screen-detected CRC had lower diagnostic activity than individuals with no CRC. In total, 308 (25.3%) of CRCs diagnosed in the invited population were diagnosed outside the screening programme. Non-participants with CRC more often had low socio-economic status, high comorbidity and stage IV CRC than participants with CRC.

CONCLUSIONS

There was a tendency that participants and those with a positive FIT had a higher diagnostic activity the year before the screening. This was not seen for those with CRC detected through screening. CRC must still be diagnosed in general practice in the invited population and non-participants are of special interest as they have higher risk of late stage CRC. Key Points Current awareness:Individuals with colorectal cancer (CRC) in screening may be symptomatic and CRC may still occur outside screening in the invited population. Most important points:The majority of individuals with CRC in screening cannot be expected to be diagnosed on symptomatic presentation in general practice GPs have to be aware that CRC still occurs outside screening in the invited population Non-participants with CRC are often deprived and have late stage CRC.

A large proportion of fecal immunochemical test-positive participants in colorectal cancer screening is symptomatic

Background

Symptomatic invitees are advised not to participate in colorectal cancer (CRC) screening but to directly consult their general practitioner (GP), because fecal immunochemical test (FIT) sensitivity for cancer is not optimal. This recommendation may not always be followed in daily practice. We evaluated how many FIT-positive participants had CRC-related symptoms and whether the presence of symptoms was associated with the presence and location of CRC/advanced neoplasia.

Methods

We prospectively collected data on CRC-related symptoms in all FIT-positive participants in the Dutch CRC screening program, referred to our endoscopy centers between 2014 and 2016, and evaluated whether symptoms were associated with detected CRC/advanced neoplasia at colonoscopy.

Results

Of 527 FIT-positive participants, 314 had advanced neoplasia, of which 41 had CRC. Overall, 246 (47%; 95% confidence interval (CI) 0.42–0.51) reported CRC-related symptoms. A change in bowel habits (odds ratio (OR) 2.86, CI 1.23–6.62) and visible blood in stool (OR 8.65, CI 2.34–32.0) were associated with the detection of CRC at colonoscopy. We did not observe significant associations between evaluated symptoms and advanced neoplasia.

Conclusions

A large proportion of FIT-positive screening participants have CRC-related symptoms. This suggests that current instructions do not retain symptomatic screening invitees from participation and awareness of CRC-related symptoms is inadequate.

Colorectal cancer screening characteristics of patients presenting with symptoms of colorectal cancer and effect on clinical outcomes

INTRODUCTION

National colorectal cancer screening, utilising a faecal occult blood test (FOBT), is now well established in the UK. The aim of this study was to define the screening characteristics of patients presenting to secondary care with symptoms of colorectal cancer and to assess the effect of screening outcome on subsequent symptomatic presentation.

METHODS

This was a retrospective analysis of all patients of screening age presenting within one calendar year in a tertiary trust via a two-week wait (2WW) pathway owing to suspicion of colorectal cancer. Colorectal cancer related outcomes were compared between patients in the cohort who had previously accepted bowel cancer screening and patients who had previously declined bowel cancer screening. The primary endpoint was overall incidence of colorectal neoplasia. Secondary endpoints included incidence of colorectal malignancy, cancer related mortality, cancer related outcomes and polyp related outcomes.

RESULTS

Overall, 2,227 patients presented via the 2WW pathway; 955 were aged 60-75 years. Among the latter, 411 (43%) had been screened previously and had a negative FOBT, and 544 (57%) had declined screening. Incidence of colorectal neoplasia did not differ between the two groups (113 [27%] vs 143 [26%], p=0.7). Of those with a negative FOBT and subsequent symptomatic presentation, 16 (3.9%) were diagnosed with a colorectal malignancy compared with 36 (6.6%) of those who declined screening and had subsequent symptomatic presentation (relative risk: 1.7, 95% confidence interval: 0.96-3.02, p=0.08). There were no differences between the two groups with regard to TNM (tumour, lymph nodes, metastasis) stage, Dukes' stage, metastases, number of polyps or cancer related mortality (median follow-up duration: 20 months).

CONCLUSIONS

The incidence of colorectal neoplasia was similar among patients who previously had a negative FOBT and those who declined screening. There was a higher incidence of colorectal cancer detected among those who declined screening but it did not reach statistical significance. All other cancer and polyp outcomes were similar between the groups.

Diagnostic value of rectal bleeding in predicting colorectal cancer: a systematic review

This study aimed at summarizing published study findings on the diagnostic value of rectal bleeding (RB) and informing clinical practice, preventive interventions and future research areas. We searched Medline and Embase for studies published by September 13, 2013 examining the risk of colorectal cancer in patients with RB using highly inclusive algorithms. Data for sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and positive predictive value (PPV) of RB were extracted by two researchers and analyzed applying Meta-Disc (version 1.4) and Stata (version 11.0). Methodological quality of studies was assessed according to QUADAS. A total of 38 studies containing 5,626 colorectal cancer patients and 73,174 participants with RB were included. The pooled sensitivity and specificity were 0.47 (95% CI: 0.45-0.48) and 0.96 (95% CI: 0.96-0.96) respectively. The overall PPVs ranged from 0.01 to 0.21 with a pooled value of 0.06 (95% CI: 0.05-0.08). Being over the age of 60 years, change in bowel habit, weight loss, anaemia, colorectal cancer among first-degree relatives and feeling of incomplete evacuation of rectum appeared to increase the predictive value of RB. Although RB greatly increases the probability of diagnosing colorectal cancer, it alone may not be sufficient for proposing further sophisticated investigations. However, given the high specificity, subjects without RB may be ruled out of further investigations. Future studies should focus on strategies using RB as an "alarm" symptom and finding additional indications to justify whether there is a need for further investigations.

Minimal benefit of earlier-than-recommended repeat colonoscopy among US Medicare enrollees following a negative colonoscopy

BACKGROUND

A large proportion of US Medicare beneficiaries undergo earlier-than-recommended follow-up colonoscopies after negative screening colonoscopy. Such practice entails substantial cost and added risk.

AIMS

To compare the risk of colorectal cancer (CRC) associated with varying follow-up colonoscopy intervals following a negative colonoscopy, and to determine whether the potential benefit of a shorter colonoscopy follow-up interval would differ by gender.

METHODS

We conducted a weighted cohort study using the Surveillance, Epidemiology and End Results-Medicare linked database (1991-2006) among 932,370 Medicare enrollees who are representative of the entire US elderly population. We compared the cumulative incidence of CRC among patients who underwent follow-up colonoscopies at different intervals following a negative colonoscopy. The primary outcome was incident CRC.

RESULTS

The eligible study cohort (n = 480,864) included 106,924 patients who underwent ≥1 colonoscopy. Men were more likely to require polypectomy during their initial colonoscopy than women. Compared to the recommended 9-10 year follow-up colonoscopy interval, an interval of 5-6 years was associated with the largest CRC cumulative risk reduction [i.e. 0.17% (95% CI: 0.009-0.32%)]. The magnitude of risk reduction associated with shorter colonoscopy follow-up intervals was not significantly different between men and women.

CONCLUSIONS

Among elderly individuals who undergo a negative colonoscopy, the magnitude of reduction in the cumulative CRC risk afforded by earlier-than-recommended follow-up colonoscopy is quite small, and probably cannot justify the risk and cost of increased colonoscopy frequency. In addition, there are insufficient differences between men and women to warrant gender-specific recommendations.

Two-week wait symptoms are prevalent in screened patients with a positive faecal occult blood test but do not predict cancer

AIM

Lower gastrointestinal (LGI) symptoms are prevalent in patients screened for bowel cancer yet do not predict a finding of cancer. This study evaluates symptoms in patients with these characteristics against the 2-week wait (2ww) criteria to determine whether they predicted cancer in these patients.

METHOD

A prospective cohort study was performed. Patients with a positive faecal occult blood (FOB) test attending our unit over a 7-month period were included. Data on symptom prevalence, frequency and duration were collected and assessed against the 2ww criteria. Associations between symptom prevalence and patient outcome were investigated using the χ(2) test.

RESULTS

Three hundred and ninety-seven patients were included and 37 (9%) were found to have colorectal cancer (CRC). The prevalence of undefined LGI symptoms was 71% and appeared comparable between those with and without CRC (65 vs 72%, P = 0.385). 2ww symptoms were reported in 147 (37%), with 2ww change in bowel habit in 10% and 2ww rectal bleeding in 31%. 2ww symptom prevalence was similar in those with and without cancer (38 vs 37%, P = 0.915). No significant differences in overall 2ww prevalence or prevalence of individual 2ww symptoms were demonstrated between those with a normal colonoscopy or one showing cancer, polyps or other pathology. Twenty nine per cent of patients with 2ww symptoms had reported these to their GP.

CONCLUSION

Undefined LGI symptoms are prevalent in FOB-positive patients but do not predict CRC. 2ww symptoms are also highly prevalent, yet similarly fail to predict cancer. Further efforts to increase public awareness of cancer symptoms are required, whilst false reassurance from a negative FOB result should be discouraged.

Symptoms do not predict colorectal cancer in an FOB screened population

BACKGROUND AND AIMS

The Scottish Bowel Screening Programme aims to detect cancer in asymptomatic individuals. We aimed to measure the prevalence of lower gastrointestinal symptoms in faecal occult blood (FOB) screen-positive patients, to correlate the symptoms with neoplasia and to compare the predictive value of FOB screening with urgent symptomatic referrals in Ayrshire and Arran.

METHODS

Data were collected prospectively on FOB screen-positive patients undergoing colonoscopy. Patients completed a symptom questionnaire. Positive predictive values (PPVs) for detecting neoplasia were calculated and a chi-square test was performed to determine any influence of symptoms in diagnosing neoplasia. Symptomatic patients undergoing colonoscopy via a general practice fast-track system were compared.

RESULTS

A total of 378 FOB screen-positive patients were included. In all, 198 (52%) had colorectal symptoms. Overall, 32 were diagnosed with colorectal cancer and 93 had polyps . FOB positivity and symptoms gave a PPV of 34% for neoplasia. FOB positivity without symptoms gave a PPV of 32% for neoplasia. Urgent referral of symptomatic patients had a lower PPV of 21% for neoplasia (p < 0.001).

CONCLUSION

Half the FOB screen-positive patients had bowel symptoms. Symptoms in these patients had no correlation with an increased rate of neoplasia. The PPV for neoplasia is superior in symptomatic and asymptomatic screen-positive patients when compared to conventional urgent symptom-based referral.

Impact of the bowel-screening programme on the diagnosis of colorectal cancer in Ayrshire and Arran

AIM

Bowel screening aims to reduce colorectal-cancer mortality by the detection and treatment of early-stage asymptomatic disease and the removal of precancerous adenomas. Bowel screening started in Ayrshire and Arran in September 2007. We report the impact of this screening on the diagnosis and stage of colorectal cancer and characterize screen-detected cancers in comparison with those diagnosed through other pathways.

METHOD

Diagnoses were identified from an audit database. Referrals were grouped into screen detected, routine, urgent and emergency presentations.

RESULTS

Between January 2001 and December 2010, 2289 diagnoses of colorectal cancer were made. From 2001 to 2006, the mean (range) number of new colorectal-cancer diagnoses per year was 210 (198-220). Between 2007 and 2010, the mean (range) number of diagnoses per year was 256 (239-274), a significant (P = 0.008) increase. Since September 2007, 877 colorectal cancers have been diagnosed: 17% were screen detected; 11% were detected as a result of routine GP referral; 51% were detected after urgent GP referral; and 21% were emergency presentations. TNM stage increased with urgency of referral. Approximately two-thirds (66%) of screen-detected colorectal cancers were node negative vs 25% of emergency presentations (P < 0.001). Most screen-detected cancers were distal to the splenic flexure (75%). Screened cancers had favourable pathology; lower T and N stages (both P < 0.001), less venous invasion (P < 0.001) and better differentiation (P < 0.05). Similar results were seen after stratification for TNM stage. Screening has not yet resulted in a significant shift towards early-stage disease since 2007.

CONCLUSION

Screening has been associated with an increase in the numbers of both new and early-stage colorectal cancers. Screen-detected cancers are predominantly early-stage disease with favourable pathology. At present, it remains to be seen whether screening will ultimately translate into an overall reduction in advanced-stage disease.

Most bowel cancer symptoms do not indicate colorectal cancer and polyps: a systematic review

BACKGROUND

Bowel symptoms are often considered an indication to perform colonoscopy to identify or rule out colorectal cancer or precancerous polyps. Investigation of bowel symptoms for this purpose is recommended by numerous clinical guidelines. However, the evidence for this practice is unclear. The objective of this study is to systematically review the evidence about the association between bowel symptoms and colorectal cancer or polyps.

METHODS

We searched the literature extensively up to December 2008, using MEDLINE and EMBASE and following references. For inclusion in the review, papers from cross sectional, case control and cohort studies had to provide a 2×2 table of symptoms by diagnosis (colorectal cancer or polyps) or sufficient data from which that table could be constructed. The search procedure, quality appraisal, and data extraction was done twice, with disagreements resolved with another reviewer. Summary ROC analysis was used to assess the diagnostic performance of symptoms to detect colorectal cancer and polyps.

RESULTS

Colorectal cancer was associated with rectal bleeding (AUC 0.66; LR+ 1.9; LR- 0.7) and weight loss (AUC 0.67, LR+ 2.5, LR- 0.9). Neither of these symptoms was associated with the presence of polyps. There was no significant association of colorectal cancer or polyps with change in bowel habit, constipation, diarrhoea or abdominal pain. Neither the clinical setting (primary or specialist care) nor study type was associated with accuracy.Most studies had methodological flaws. There was no consistency in the way symptoms were elicited or interpreted in the studies.

CONCLUSIONS

Current evidence suggests that the common practice of performing colonoscopies to identify cancers in people with bowel symptoms is warranted only for rectal bleeding and the general symptom of weight loss. Bodies preparing guidelines for clinicians and consumers to improve early detection of colorectal cancer need to take into account the limited value of symptoms.

Colorectal cancer mortality prevented by use and attributable to nonuse of colonoscopy

BACKGROUND

Use of colonoscopy is thought to reduce colorectal cancer (CRC) mortality, but its impact at the population level is unclear.

OBJECTIVE

To estimate the effect of current colonoscopy use on CRC mortality and its further potential in reducing CRC mortality.

DESIGN

Population-level analysis was performed by using the concepts of prevented and attributable fractions, by using data from the National Health Interview Survey, the Surveillance, Epidemiology and End Results Program, and estimates of the effectiveness of colonoscopy at reducing CRC mortality.

SETTING

The 2005 U.S. population aged 50 years and older.

EXPOSURE

Colonoscopy within 10 years or less.

MAIN OUTCOME MEASUREMENTS

Percentages and absolute numbers of CRC deaths prevented and potentially preventable by colonoscopy.

LIMITATIONS

Uncertainty in effectiveness estimates.

RESULTS

Overall, the proportions of CRC deaths in 2005 prevented by colonoscopy (ie, the prevented fractions) range from 13% (95% CI, 11%-15%) to 19% (95% CI, 12%-24%) across the estimates of colonoscopy effectiveness. Corresponding numbers of CRC deaths prevented range from 7314 (95% CI, 6010-8467) to 11,711 (95% CI, 7077-14,898). The proportions of CRC deaths attributable to nonuse of colonoscopy (ie, the attributable fractions) range from 28% (95% CI, 22%-33%) to 44% (95% CI, 24%-60%), depending on the assumed effectiveness. Corresponding numbers of CRC deaths attributed to nonuse of colonoscopy range from 13,796 (95% CI, 11,076-16,255) to 22,088 (95% CI, 12,189-29,947).

CONCLUSIONS

Although we estimate that colonoscopy has prevented substantial numbers of CRC deaths, many more deaths could have been prevented with more widespread use. These findings highlight the potential benefits from public health interventions to increase the use of screening colonoscopy.

Male sex and smoking have a larger impact on the prevalence of colorectal neoplasia than family history of colorectal cancer

BACKGROUND & AIMS

Screening recommendations for colorectal cancer (CRC) commonly take family history but no other risk factors into account. We compared and assessed risk factors of colorectal polyps in a large population undergoing screening colonoscopy.

METHODS

We conducted a population-based cross-sectional study that included 3349 subjects, 55 years or older (mean ages of men and women, 63.6 and 63.4 years, respectively), who underwent colonoscopy for the first time within the nationwide colonoscopy screening program in Germany. We calculated prevalences of colorectal polyps and estimated multivariate prevalence ratios (PRs) and population attributable fractions (PAFs).

RESULTS

Overall, 654 subjects had hyperplastic polyps (20%), 675 had non-advanced adenomas (20%), 343 had advanced adenomas (10%), and 40 had CRC (1%). Risk factor prevalences and adjusted PRs were higher for male gender and smoking than for family history of CRC. PAFs for prevalence of non-advanced and advanced neoplasia were highest for male gender (23% and 23%, respectively), followed by smoking (7% and 9%, respectively), and family history of CRC (2% and 4%, respectively).

CONCLUSIONS

Male gender and smoking have a larger impact on the prevalence of colorectal neoplasia than family history, suggesting an extensive evaluation of additional risk stratification in population-based screening, particularly by sex.

Adenomatous colorectal polyps in patients referred for colonoscopy in a regional hospital in Kuwait

BACKGROUND/AIM

Adenomatous colorectal polyps (ACPs) are known to be the precursor lesions for colorectal cancer. The aim of the study was to determine the prevalence, endoscopic and pathological features of ACPs in patients referred for colonoscopy.

PATIENTS AND METHODS

The endoscopic and histological reports of adult patients who underwent complete colonoscopy in the gastroenterology unit of a regional Kuwaiti hospital between January 2008 and December 2008 were retrospectively studied. The specimens of polyps were reviewed by an experienced pathologist who was blinded to the clinical or endoscopic information. Non-neoplastic polyps were not included in the analysis.

RESULTS

Of 530 eligible patients (mean age, 45 years; male-female ratio, 2:1), 54 (10%) had 103 ACPs. Of the patients with ACPs (mean age, 57 years), 43 (80%) were males and 36 (67%) were Kuwaitis. Histopathological examination of the most significant polyp in each patient revealed that 40 (74%) polyps were tubular adenomas (TAs); 11 (20%), tubulovillous (TV) adenomas; and 3 (6%), villous adenomas. High-grade dysplasia was noticed in 4 (10%) adenomas. Fifteen (2.8%) of the 530 patients had advanced ACPs. Logistic regression analysis of some variables and their association with ACPs found that age (P < 0.001; OR, 1.9; CI, 1.5-2.3), history of adenoma (P=0.001; OR, 6.4; CI, .2.1-19.4) and being Kuwaitis (P=0.029; OR, 2.1; CI, 1.1-4.1) to be independently associated with ACPs.

CONCLUSION

The most common histological type of ACPs was tubular adenoma. Advancing age, being Kuwaiti nationals and prior removal of ACPs were significantly associated with the occurrence of ACPs.

The misuse of the faecal occult blood test under the lower gastrointestinal two week wait rule

AIM

To find the proportion of patients with a faecal occult blood (FOB) performed as part of the referral for the lower gastrointestinal two week wait (2WW) referral system, and whether this correlates with the cancer status.

METHOD

All patients referred to the colorectal cancer service using the 2WW referral criteria, between August 2005 and August 2007, were identified using the hospital's cancer audit database. Faecal occult bloods and cancer status were recorded for each patient.

RESULTS

Two thousand one hundred and fifty-nine patients (1177 female: 903 male; median age 58; age range 18-98) were referred by general practitioners. The FOBT was only performed on three samples in all cases. In total, 172 of 2159 patients (7.9%) had an FOB performed prior to their referral, with 55 of 172 patients (31.9%) as part of the referral for 2WW. Sixteen of 172 patients (9.3%) had an FOB performed in the presence of overt rectal bleeding. In only 2 of 172 patients (1.1%) the FOB correlated with a colorectal cancer. Unnecessary testing for FOB costs has cost pound4072.96 in total.

DISCUSSION

A significant number of faecal occult bloods are being performed and the detection rate, even in this symptomatic group of patients, is very low. It is evident that the test is being performed in the community on three samples and not six. This, combined with the high false positive rate, leads to patients not only undergoing unnecessary psycho-social consequences but could potentially lead to significant risks from unnecessary invasive investigation as well as the added financial burden of test itself.

Clinical predictors of colorectal polyps and carcinoma in a low prevalence region: Results of a colonoscopy based study

AIM: To estimate the prevalence of colorectal cancer (CRC) in patients with long lasting colonic symptoms undergoing total colonoscopy; and to establish clinical features predicting its occurrence.

METHODS: This prospective study was carried out in Imam Hospital, Tabriz University of medical sciences, Iran. Continuous patients with long lasting lower gastrointestinal tract symptoms who had the criteria of a colonoscopy were included. The endoscopist visualized the caecum documented by a photo and/or a specimen from terminal ileum.

RESULTS: Four hundred and eighty consecutive symptomatic patients [mean age (SD): 42.73 (16.21)] were included. The prevalence of colorectal neoplasia was 15.3% (34 subjects) and 37.7% (181 subjects) had a completely normal colon. Adenomatous polyps were detected in 56 (11.7%) patients, in 12.3% of men and 10.9% of women. The mean age of the patients with a polyp was significantly higher than the others (49.53 ± 14.16 vs 41.85 ± 16.26, P = 0.001). Most of the adenomatous polyps were left sided and tubular; only 22.5% of polyps were more than 10 mm. Cancer was detected in 16 (3.6%) of our study population, which was mostly right sided (57.2%). The mean age of patients with cancer was significantly higher than the others (60.25 ± 8.26 vs 42.13 ± 16.08, P < 0.005) and higher than patients with polyps [60.25 (8.26) vs 49.53 (1.91) (P < 0.0005)]. None of the symptoms (diarrhea, abdominal pain, rectal bleeding, constipation, altering diarrhea and constipation, history of cancer, known irritable bowel disease, history of polyp and fissure or family history of cancer) were predictors for cancer or polyps, but the age of the patient and unexplained anemia independently predicted cancer.

CONCLUSION: Less advanced patterns and smaller sizes of adenomas in Iran is compatible with other data from Asia and the Middle East, but in contrast to western countries. Prevalence of colonic neoplasia in our community seems to be lower than that in western population. Colonic symptoms are not predictors for polyps or cancer but unexplained anemia and elder age can predict CRC.

Existe diferença no estadiamento entre doentes operados de câncer colorretal no sistema previdenciário e na clinica privada?

OBJETIVO: Avaliar se existe diferença no estadiamento de doentes submetidos à ressecção intestinal por câncer colorretal no sistema previdenciário e na clínica privada. MÉTODO: Foram estudados de forma retrospectiva 41 doentes (16 homens e 25 mulheres) com idade média de 59,4 anos operados no sistema previdenciário (SP) e 33 doentes (18 homens e 15 mulheres) com idade média de 60,8 anos operados na clínica privada (CP). Foram avaliados o estadiamento TNM, a frequência de operações de urgência, de operações paliativas e do uso de colostomia. RESULTADOS: Não se observou diferença entre o estadiamento dos dois grupos. A frequência de operações de urgência foi 26,8% no SP e 12,1% na CP (p=0,100). As operações paliativas ( 19,5% SP x 6,1% CP) e o uso de colostomia ( 26,8 SP X 15,2 CP) foram maiores no sistema previdenciário porém os valores não foram estatisticamente significantes, valores de p=0,087 e p=0,352 respectivamente. CONCLUSÃO: Não há diferença significante entre o estadiamento TNM de doentes operados no sistema previdenciário e privado.

Reported symptoms, diagnostic delay and stage of colorectal cancer: a population-based study in Denmark

OBJECTIVE

The primary prognostic factor for colorectal cancer (CRC) is stage. Any association between symptoms, diagnostic delay and stage may have implications for the clinical course of the disease. We examined the association between symptoms and diagnostic delay and between symptoms and stage, and assessed whether the associations differed for colon cancer (CC) and rectal cancer (RC).

PATIENTS AND METHODS

Population-based prospective observational study based on 733 Danish CRC patients. Diagnostic delay and patients' reported symptoms were determined through questionnaire-interviews. Dukes' stage was obtained from medical records and pathology forms. Diagnostic delay was categorized into three delay groups: < or = 60, 61-150 and > 150 days. Stage was classified into nonadvanced (Dukes' A and B) or advanced (Dukes' C and D) cancers. We calculated the frequency of the most frequently reported initial symptom or symptom complex for CC and RC patients, and evaluated the frequency of patients with different initial symptoms/symptom complexes in the three delay groups. For the most frequent initial symptoms/symptom complexes, we calculated the frequencies according to stage, and estimated the relative risk of having an advanced stage, with 95% confidence intervals.

RESULTS

The most frequent initial symptoms/symptom complexes were very vague symptoms for CC and rectal bleeding for RC. For both CC and RC, rectal bleeding was significantly associated with nonadvanced stage. The relative risk of having an advanced cancer was 0.6 for monosymptomatic rectal bleeding and 0.7 for rectal bleeding combined with other symptoms.

CONCLUSIONS

Initial symptoms of CC were often very vague, making it difficult to identify a precise start date. The most frequent initial symptom/symptom complex for RC - rectal bleeding - was better defined. Rectal bleeding was significantly associated with nonadvanced CC and RC and a significantly decreased relative risk of having an advanced cancer.