The Reply

Effectiveness of complete diagnostic examination in clinical practice settings

6035 Background: Annual fecal occult blood testing (FOBT) is the only colon cancer screening shown to reduce colon cancer incidence and mortality in randomized controlled trials. The true benefits of screening are only realized when total colon examination (TCE) is performed as follow-up to an abnormal screening result. Methods: We used the 2000 National Health Interview Survey (NHIS) Cancer Control Supplement, a nationally representative sample of households, to examine follow-up after abnormal FOBT and the content of this follow-up. Persons who reported undergoing an FOBT were the population of interest. Reasons for FOBT, results of test, and follow-up after an abnormal FOBT were examined. Inadequate follow-up after a positive FOBT included no follow-up or another FOBT. TCE was defined as sigmoidoscopy with double contrast barium enema (DCBE) or colonoscopy. We used SUDAAN to obtain population estimates. Results: We included 4,908 respondents who indicated they had undergone FOBT (79.8% as part of the routine physical examination, 14.7% for a specific problem, 2.0% as follow-up of a previous abnormal test/screening examine, 1.4% family history). Overall, 5.7% of respondents reported an abnormal test, varying by reason for test (3.5% for screening and 16.9% for those who had FOBT done for a specific problem). For those reporting an abnormal FOBT during screening, 62.9% had some follow-up diagnostic procedures. Fifty-three percent reported having a TCE as defined above. Forty-seven percent either had no further evaluation, another FOBT or incomplete colon examination with sigmoidoscopy alone, and DCBE only or a surgical evaluation. Those who had FOBT completed for a specific problem had more surgical evaluations (18.4%) and fewer TCEs (44.3%). Conclusions: Among a nationally-representative sample of adults who reported FOBT as a screening test for colorectal cancer, close to 63% had some type of follow-up. Only 53% of those with a positive screening FOBT had a TCE. These results suggest that the full potential of CRC screening is not being realized, and point to the need to improve follow-up of abnormal FOBT results. No significant financial relationships to disclose.

Introduction: Fecal occult blood tests (FOBTs) have been used as a tool for detecting occult blood in stool for colon cancer screening. Increasingly, FOBT has been utilized by clinicians to detect gastrointestinal (GI) bleeding in the hospital setting without evidence supporting its use. Furthermore, a false positive FOBT can lead to excessive patient harm in the form of unnecessary testing, patient anxiety, prolonged hospital stay, and financial hardship. In this study, we looked at the use of FOBTs, relevant specialist consults, and further endoscopic interventions in the inpatient setting. Methods: Our search criteria included patient demographics, length of stay, admission diagnosis, specialty consulted, FOBT ordering provider, FOBT results, intervention performed, and total blood volume ordered. Patient data was gathered using Epic Workbench. Data were analyzed using SPSS. Frequencies of age, sex, race, and length of stay were calculated. Descriptive statistics were obtained to compare FOBT results with the number of procedures and specialist consults. Pearson chi-square was used in the analysis of statistical significance. Results: Over one year, a total of 742 patients received a FOBT while inpatient: 411 females and 333 males; predominantly white (97.3%) with a median age of 71. A total of 433 FOBTs were positive, of which 27 resulted in a colonoscopy and 46 in gastroscopy. Consults to specialty services were placed on 222 positive FOBT results and 187 negative FOBT results. Overall, FOBT did have a significant impact on whether an invasive intervention, such as colonoscopy or gastroscopy, was performed (p < 0.001). FOBT results were not statistically associated with consults placed (p < 0.5). (Figure) Conclusion: Despite questionable benefits, the use of FOBTs has extended to inpatient and emergency department settings. Reasons for use included anemia, GI bleeds, abdominal pain, melena, and emesis. Two studies looked at the use of FOBTs in the community hospital setting and both found that FOBTs were used for non-evidence-based indications and did not offer any clinical benefit. Data analysis from our study revealed that of the 433 patients with a positive FOBT, only 73 did underwent an intervention. Consequently, the results of a FOBT do not appear to play a large role in deciding further intervention. In order to increase patient benefit and decrease healthcare burden, we plan to further this work by implementing provider education on the uses of FOBT and reporting on the color of stool samples. (Table)Figure 1.: Graphical representation of specialist consults placed compared with positive and negative FOBT results. Blue bars represent number of FOBTs with a consult and orange bars represent number of FOBTs without a consult. Table 1. - Comparison of FOBT with procedures completed Colonoscopy Esophagogastroduodenoscopy No scope Total Occult blood Positive 27 46 360 433 Negative 5 7 297 309 Total 32 53 657 742

The faecal occult blood test (FOBT) is the screening test validated for use in the National Health Service (NHS) Bowel Cancer Screening Programme (BCSP) after trials demonstrated a 16% reduction in colorectal cancer-specific mortality. FOBT is not validated for use outside the BCSP. The aim was to investigate the number of FOBTs performed outside of the NHS BCSP at a single centre. All FOBTs performed over 1 year were identified. Basic patient demographics, requesting physician and FOBT results were obtained. Referrals and outcomes of the investigation following the FOBT were collected. A total of 758 FOBTs were requested in 701 patients (352 female; median age 69; range 16-99). The majority (91%) were requested by general practitioners. A total of 515 out of 758 tests (68%) were performed in patients outside the NHS BCSP age range. Thirty-seven out of 86 positive FOBTs were investigated, diagnosing four rectal cancers and two polyps. Forty-nine out of 87 patients with a positive FOBT were not investigated further by the requesting physician or the test repeated. Of the remaining 672 FOBTs, 615 were negative and 57 were either incomplete or unsuitable for analysis. A total of 111 patients (18%) were referred to hospital and 105 of these had FOBT performed as part of the referral process. Our study demonstrates significant misuse of the FOBT outside the NHS BCSP. Inappropriate use leads to false positives and exposes patients to unnecessary risk. False negatives provide reassurance to patients who may have symptoms that should be investigated. The FOBT should not be available to physicians in either primary or secondary care and be restricted to NHS BCSP.

Immunochemical tests show important advantages over chemical-based faecal occult blood tests (FOBT) for colorectal cancer (CRC) screening, but comparison studies are limited. This study was performed to compare the accuracy of a sensitive immunochemical test with the guaiac test for detecting significant neoplasia (advanced adenomas and CRC) in an average-risk population. A random sample of 2288 asymptomatic subjects 50-79 years of age was prospectively included. Participants received three cards of the guaiac test, one sample of a latex-agglutination test (haemoglobin cut-off 50 ng/ml), and an invitation to undergo colonoscopy. Test sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated in 1756 compliers. Immunochemical and guaiac tests were positive in 143 (8.1%) and 62 (3.5%) subjects, respectively. Complete colonoscopy, performed in 402 participants (158 FOBT+ and 244 FOBT-), detected 14 (0.8%) patients with CRC and 49 (2.8%) with advanced adenomas. The immunochemical and guaiac tests for significant colorectal neoplasia showed sensitivities of 61% versus 23.8%, specificities of 95.1% versus 97.7%, PPVs of 43.4% versus 39.0%, and NPVs of 97.5% versus 95.4%, respectively. Proximal significant neoplasms were more frequently detected with the immunochemical test (85% vs. 15%) The relative risk for detecting significant neoplasia was superior in patients with a positive immunochemical test (RR 16.93; CI 7.94-36.10) than with a positive guaiac test (RR 3.34; CI 2.17-5.15). A sensitive immunochemical test is markedly superior to the guaiac test for detecting significant colorectal neoplasia, and should be considered the first-choice FOBT for CRC screening in the average-risk population.

Objective The fecal occult blood (FOB) test is commonly used for colorectal cancer screening; however, it is uncertain if further diagnostic interventions, such as a colonoscopy, should be performed based on its results. Method To better understand patient behavior following the FOB test, 6,414 patients (3,807 men and 2,607 women) who underwent colonoscopy between August 2015 and March 2016 at any of the 26 medical institutions throughout Hiroshima Prefecture were invited to participate in the study. All patients provided their written consent, after which they completed a questionnaire, and their colonoscopy results were obtained. These datasets were analyzed in a blinded manner, and the unique codes linking the records were revealed at the end of the analysis. Results Of the total study population, 4,749 patients (74.0%) had previously undergone FOB testing. After classification of common behavioral responses that the patients displayed following their FOB test, the group who had undergone the test several times, who had not had positive test results in the past, and whose latest FOB test results were positive had a significantly higher diagnosis rate of both early- and advanced-stage cancer than the other groups. Furthermore, patients in whom several previous FOB test results had been negative whose previous colonoscopy was positive were associated with a higher diagnosis rate of early-stage cancer than other groups. Conclusion These results suggested that colonoscopy should be performed immediately for patients with positive FOB test results due to their association with colorectal cancer and the possible detection of cancer at an early stage.

Flexible sigmoidoscopy screening at around age 60 can reduce colorectal cancer incidence. Insufficient evidence exists on flexible sigmoidoscopy at age 60 in a population being offered biennial faecal occult blood test screening from age 50. This randomized controlled trial assessed if flexible sigmoidoscopy would be an effective adjunct to faecal occult blood test. In the Scottish Bowel Screening Programme between June 2014 and December 2015, 51,769 individuals were randomized to be offered flexible sigmoidoscopy instead of faecal occult blood test at age 60 or to continue faecal occult blood test. Those not accepting flexible sigmoidoscopy and those with normal flexible sigmoidoscopy were offered faecal occult blood test. All with flexible sigmoidoscopy-detected neoplasia or a positive faecal occult blood test result were offered colonoscopy. Overall flexible sigmoidoscopy uptake was 17.8%, higher in men than women, and decreased with increasing deprivation (25.7% in the least to 9.2% in the most deprived quintile). In those who underwent flexible sigmoidoscopy, detection rate for colorectal cancer was 0.13%, for adenoma 7.27%, and for total neoplasia 7.40%. In those who underwent colonoscopy after a positive flexible sigmoidoscopy, detection rate for colorectal cancer was 0.28%, adenoma 8.66%, and total neoplasia 8.83%. On an intention to screen basis, there was no difference in colorectal cancer detection rate between the study and control groups. Adenoma and total neoplasia detection rate were significantly higher in the study group, with odds ratios of 5.95 (95%CI: 4.69-7.56) and 5.10 (95%CI: 4.09-6.35), respectively. In a single screening round at age 60, there was low uptake and neoplasia detection rate. Flexible sigmoidoscopy detected significantly more neoplasia than faecal occult blood test alone.

ObjectiveFaecal immunochemical tests (FIT) are replacing guaiac faecal occult blood tests (FOBT) in colorectal cancer (CRC) screening. Data from the first year of FIT screening were compared with those from...

Colon Cancer Screening Models: Lessons and Challenges

Despite evidence that several colorectal cancer (CRC) screening strategies can reduce CRC mortality, screening rates remain low. This study aimed to determine whether the approach by which screening is recommended influences adherence. We used a cluster randomization design with clinic time block as the unit of randomization. Persons at average risk for development of CRC in a racially/ethnically diverse urban setting were randomized to receive recommendation for screening by fecal occult blood testing (FOBT), colonoscopy, or their choice of FOBT or colonoscopy. The primary outcome was completion of CRC screening within 12 months after enrollment, defined as performance of colonoscopy, or 3 FOBT cards plus colonoscopy for any positive FOBT result. Secondary analyses evaluated sociodemographic factors associated with completion of screening. A total of 997 participants were enrolled; 58% completed the CRC screening strategy they were assigned or chose. However, participants who were recommended colonoscopy completed screening at a significantly lower rate (38%) than participants who were recommended FOBT (67%) (P<.001) or given a choice between FOBT or colonoscopy (69%) (P<.001). Latinos and Asians (primarily Chinese) completed screening more often than African Americans. Moreover, nonwhite participants adhered more often to FOBT, while white participants adhered more often to colonoscopy. The common practice of universally recommending colonoscopy may reduce adherence to CRC screening, especially among racial/ethnic minorities. Significant variation in overall and strategy-specific adherence exists between racial/ethnic groups; however, this may be a proxy for health beliefs and/or language. These results suggest that patient preferences should be considered when making CRC screening recommendations. Trial Registration clinicaltrials.gov Identifier: NCT00705731.

Faecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all screen positive persons have negative colonoscopy, but consensus is lacking on how these persons should be followed up. Health authorities in Denmark and The Netherlands recommend suspending screening for 8-10 years, while patients in UK are invited to screening after 2 years. In this cohort-study, we followed 166,277 individuals invited to FOBT-screening in 2005-2006 and a reference group comprising the remaining 1,240,348 Danes of the same age. We linked Danish population and health service registers to obtain information about colonoscopy outcome and incident CRC. We estimated CRC risk by colonoscopy outcome (adenoma, other colorectal pathology or negative colonoscopy) for the reference group, the screening group, and subgroups. Persons with positive screening FOBT followed by negative colonoscopy had the same long-term CRC risk as persons with adenoma detected due to a positive screening FOBT (aHR 1.33, 95% CI: 0.65-2.71). We found no difference in the long-term CRC risk between persons with negative colonoscopy after a positive FOBT screening test and the unscreened reference population (aHR 1.05, 95% CI: 0.62-1.78). Since FOBT screen positive persons in our study remained at average risk of CRC despite of a negative index colonoscopy, we question the safety of suspending FOBT screening for this group. It needs to be monitored whether recent efforts to improve colonoscopy quality have been successful in ensuring low CRC risk after negative colonoscopy also in FOBT positive persons.

IntroductionThe English NHS Bowel Cancer Screening Programme (BCSP) uses guaiac based faecal occult blood test (FOBT) as the screening tool, with people with a positive result undergoing colonoscopy. Subjects with...

There is no guideline defining the optimal time from a positive screening fecal occult blood test to follow-up colonoscopy. We reviewed records of 231 consecutive primary care patients who received a colonoscopy within 18 months of a positive fecal occult blood test. We examined the relationship between time to colonoscopy and risk of neoplasia on colonoscopy using a logistic regression analysis adjusting for potential confounders such as age, race, and gender. The mean time to colonoscopy was 236 days. Longer time to colonoscopy (OR = 1.10, P = 0.01) and older age (OR 1.04, P = 0.01) were associated with higher odds of neoplasia. The association of time with advanced neoplasia was positive, but not statistically significant (OR 1.07, P = 0.14). In this study, a longer interval to colonoscopy after fecal occult blood test was associated with an increased risk of neoplasia. Determining the optimal interval for follow-up is desirable and will require larger studies.

A sizeable number of individuals who participate in population-based colorectal cancer (CRC) screening programs and have a positive fecal occult blood test (FOBT) do not have an identifiable lesion found at colonoscopy to account for their positive FOBT screen. To evaluate the evidence and provide recommendations regarding the use of routine esophagogastroduodenoscopy (EGD) to detect upper gastrointestinal (UGI) cancers in patients participating in a population-based CRC screening program who are FOBT positive and colonoscopy negative. A systematic review was used to develop the evidentiary base and to inform the evidence-based recommendations provided. Nine studies identified a group of patients who were FOBT positive and colonoscopy negative. Three studies found no cases of UGI cancer. Four studies reported cases of UGI cancer; three found UGI cancer in 1% or less of the population studied, and one study found one case of UGI cancer that represented 7% of their small subgroup of FOBT-positive/colonoscopy-negative patients. Two studies did not provide outcome information that could be specifically related to the FOBT-positive/colonoscopy-negative subgroup. The current body of evidence is insufficient to recommend for or against routine EGD as a means of detecting gastric or esophageal cancers for patients who are FOBT positive/colonoscopy negative, in a population-based CRC screening program. The decision to perform EGD should be individualized and based on clinical judgement.

Association of fecal occult blood tests results with colonoscopic findings in a general hospital and validation of the screening test