Interval Cancers in Screening with Fecal Occult Blood Test for Colorectal Cancer

Interval cancers, which are cancers diagnosed in spite of one or more negative screening tests, were studied in a randomized population with Hemoccult-II for colorectal cancer in 61,938 persons between 45 and 74 years old. Three biannual screenings were performed from 1985 to 1991, and 52% of all the cancers detected after doing at least one Hemoccult-II test were interval cancers (81 persons). These were more advanced than cancers diagnosed after a positive Hemoccult-II test, of larger size, less frequently of Dukes stage A, more often invading neighboring organs, and less often resectable for cure. They were located in the rectum more often than cancers diagnosed by screening and cancers in controls. Otherwise, interval cancers did not differ from cancers in controls or cancers in non-responders, and all characteristics suggested that no delay in diagnosis resulted from one or more negative Hemoccult-II tests, compared with controls. However, even if screening with Hemoccult-II demonstrates a reduction in mortality from colorectal cancer, the present high number of interval cancers makes it necessary to look for other methods of screening populations for colorectal cancer.     

Acceptability and Compliance in Screening for Colorectal Cancer with Fecal Occult Blood Test

To evaluate acceptability of and compliance with the Hemoccult-II guaiac test in screening for occult fecal blood, a representative sample of 685 persons 40–74 years old received slides and invitation without previous notice. Sixty-seven per cent accepted. Eight persons (1.7%) had a positive test. Two had rectal cancer, and two had adenomas. Acceptability decreased significantly with age in women but not in men. Eighty-seven per cent agreed to repeated screenings with intervals of 1–2 years. The acceptability was favorable compared with other studies and suggests 70–74 years as the upper limit for screening. Acceptability may even be increased by further information to the population. Written reminders were effective, but telephone calls were not. Compliance was high, since only 20 persons needed further instructions, and the proportion of false-positive tests suggested that dietary instructions had been followed. The high acceptability favors the planning of a major randomized trial of the possible effect of screening on mortality from colorectal cancer.     

Upper Gastrointestinal Cancer in a Population-based Screening Program with Fecal Occult Blood Test for Colorectal Cancer

Background : Screening with Hemoccult-II ® (H-II) followed by colonoscopy, when fecal occult blood is demonstrated, reduces mortality from colorectal cancer. Whether upper gastrointestinal investigation is necessary when colonoscopy does not reveal any significant colorectal lesion is doubtful, and is the subject of this study. Material : In 1985, 30,967 persons from the general population register of Funen were randomized to biennial H-II screening. A positive test was followed by colonoscopy and no attempt was made to evaluate the upper gastrointestinal tract. Based on the information from the Funen Patient Database, the National Board of Health's Register of Death Causes, the Cancer Register and the National Register of Patients, all persons with malignancy of the gastrointestinal tract were identified. Results : During 15 years and 8 screening rounds, 1,767 tests were positive; 1,536 complete colonic investigations detected colorectal cancer in 182 persons, adenoma &#83 10 mm in 440 persons, and in 879 investigations no colorectal lesion was found. Upper GI cancers were diagnosed in 209 persons within 2 years of the H-II test (199 after a negative H-II and no more than 10 persons within 2 years of a positive test). Among the 10, two were diagnosed as a consequence of symptoms at the time of screening. Conclusion : It is unjustified to perform upper gastrointestinal investigation in asymptomatic persons with a positive H-II in a Danish population screening for colorectal cancer.     

Increased Colorectal Cancer Screening Sustained with Mailed Fecal Immunochemical Test Outreach

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Immunochemical Fecal Occult Blood Test Is Inadequate for Screening Test of Stomach Cancer

The present study was carried out to investigate the diagnostic accuracy of the immunochemical fecal occult blood test in the screening for stomach cancer. In the hospital-based case–control study, the test was positive in 6 (14.3%) subjects with stomach cancer, in 32 (76.2%) subjects with colorectal cancer, and in 10 (7.9%) healthy subjects, respectively, showing a significant difference in detection rate between the subjects with stomach cancer and colorectal cancer (p < 0.01). In the population-based cross-sectional study, detection rate for stomach cancer was 0.13% and 0.15% for negative and positive groups decided by immunochemical fecal occult blood test, indicating no significant difference. These results reveal that the immunochemical fecal occult blood test is inadequate as the screening test for stomach cancer and suggest that examination of the upper digestive tract is unnecessary in cases where the result of fecal occult blood test is positive with no sign of colorectal diseases.     

Evaluation of the Sensitivity of an Immunochemical Fecal Occult Blood Test for Colorectal Neoplasia

Objectives : This study was designed to evaluate the sensitivity of OC-Hemodia, a immunochemical fecal occult blood test (IFOBT) based on the technique of latex agglutination for early stage colorectal cancer and clinically significant adenomas. Methods : The study was conducted on 885 patients who underwent OC-Hemodia and a colonoscopy. Results : Colorectal cancers were detected in 23 patients (10 Dukes' A, eight Dukes' B, and five Dukes' C or D). Adenomas were detected in 459 patients (16 villous adenomas 433 tubular adenomas with mild or moderate dysplasia, and 10 with severe dysplasia). The sensitivity of OC-Hemodia was 90% for those with Dukes' A colon cancer and 100% for those with Dukes' B, C, or D colon cancer. It was 18.8% for those with villous changes, and 40% for those with severe dysplasia. Conclusions : These results suggest that the IFOBT is not a reliable test for the screening of prenialignant adenomas, although it is useful for detecting early stage colorectal cancers.     

Colonoscopy-Related Mortality in a Fecal Immunochemical Test–Based Colorectal Cancer Screening Program

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Genetic Biomarker Prevalence Is Similar in Fecal Immunochemical Test Positive and Negative Colorectal Cancer Tissue

Background

Fecal immunochemical test (FIT) screening detects most asymptomatic colorectal cancers. Combining FIT screening with stool-based genetic biomarkers increases sensitivity for cancer, but whether DNA biomarkers (biomarkers) differ for cancers detected versus missed by FIT screening has not been evaluated in a community-based population.

Aims

To evaluate tissue biomarkers among Kaiser Permanente Northern California patients diagnosed with colorectal cancer within 2 years after FIT screening.

Methods

FIT-negative and FIT-positive colorectal cancer patients 50–77 years of age were matched on age, sex, and cancer stage. Adequate DNA was isolated from paraffin-embedded specimens in 210 FIT-negative and 211 FIT-positive patients. Quantitative allele-specific real-time target and signal amplification assays were performed for 7 K-ras mutations and 10 aberrantly methylated DNA biomarkers (NDRG4, BMP3, SFMBT2_895, SFMBT2_896, SFMBT2_897, CHST2_7890, PDGFD, VAV3, DTX1, CHST2_7889).

Results

One or more biomarkers were found in 414 of 421 CRCs (98.3%). Biomarker expression was not associated with FIT status, with the exception of higher SFMBT2_897 expression in FIT-negative (194 of 210; 92.4%) than in FIT-positive cancers (180 of 211; 85.3%; p = 0.02). There were no consistent differences in biomarker expression by FIT status within age, sex, stage, and cancer location subgroups.

Conclusions

The biomarkers of a currently in-use multi-target stool DNA test (K-ras, NDRG4, and BMP3) and eight newly characterized methylated biomarkers were commonly expressed in tumor tissue specimens, independent of FIT result. Additional study using stool-based testing with these new biomarkers will allow assessment of sensitivity, specificity, and clinical utility.

     

Time from Positive Screening Fecal Occult Blood Test to Colonoscopy and Risk of Neoplasia

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.     

Effectiveness of a Provider Reminder on Fecal Occult Blood Test Follow-up

Purpose To determine the impact of an electronic reminder upon the timeliness and proportion of patients referred for evaluation of a positive fecal occult blood test and receipt of colonoscopy. Methods Outpatients (468) with a positive occult blood test were prospectively identified and had a note entered into their electronic medical record prompting their provider to act upon this result. The results were compared to 634 control patients from the prior year. Results The intervention was associated with a 20.3% absolute increase in gastroenterology consultation within 14 days (P < 0.001) and significantly prompter consultation. The median time to colonoscopy decreased by 38 days during the intervention (P = <0.0001). A multivariable model found that the intervention was significantly associated with shorter time to consultation and colonoscopy. Conclusion A simple electronic reminder is associated with a significant improvement in the proportion of patients referred for, and timeliness of, evaluation of a positive FOBT. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the United States Government or the Department of Veterans Affairs. This study was approved by the University of Washington Institutional Review Board on September 26, 2006.     

Effectiveness of the Immunofecal Occult Blood Test for Colorectal Cancer Screening in a Large Population

Background  

Guaiac tests are the most widely used tests to detect colorectal cancer (CRC). However, their sensitivity is relatively low and results may be affected by various factors. Immunofecal occult blood test (IFOBT) is specific for human hemoglobin and does not require dietary restrictions.     

自然人群序贯粪隐血试验连续性结直肠癌普查的队列研究：19年结果分析

筛查是早期发现结直肠癌（CRC）的重要手段。目的：评价自然人群序贯粪隐血试验（SFOBT）连续性CRC普查在提高早期CRC检出率、患者长期生存率和降低CRC发生率方面的作用。方法：于1987～2005年，应用SFOBT对一组基本固定的中老年人群（初次普查人群3002例）行连续性CRC普查。每1～2年接受一次普查者计入普查组，连续3年或3年以上未接受普查者计入未普查组。FOBT阳性者行结肠镜检查。于北京军区总医院行手术治疗的1033例CRC患者作为对照组。结果：19年中普查人群共发生CRC52例，总CRC发生率为90．4／10万人·年。普查组共检出CRC25例，漏诊7例，CRC检出率为57．6／10万人·年，发生率为73．8／10万人·年；未普查组发生CRC20例，发生率为141．4／10万人·年。普查组DukesA／B期患者比例（95．5％对31．2％和43．9％，P〈0．05）和5年生存率（77．8％对33．3％和39．8％，P〈0．05）显著高于未普查组和对照组。SFOBT筛查CRC的19年总敏感性为90．6％，特异性为98．0％，阳性预测值为3．2％，阴性预测值为99．99％。结论：SFOBT应用于自然人群连续性普查可提高早期CRC检出率和患者5年生存率。切除普查中发现的腺瘤可明显降低CRC发生率。该筛查方案具有较高的敏感性和特异性，但仍需高度关注其结肠镜检查的依从性.     

Horizontal Plane Transesophageal Echocardiography May Be False Negative for Large Tricuspid Vegetations

A 37-year-old man was admitted to the hospital with fever. Because of a history of intravenous drug abuse, and a picture consistent with septic pulmonary emboli, right-sided endocarditis was suspected. However, transthoracic echocardiography did not reveal any vegetations. Transesophageal echocardiography was therefore done, and excellent visualization of the tricuspid valve with the horizontal plane view showed what appeared to be a normal tricuspid valve. However, the vertical plane image clearly showed a large tricuspid vegetation. This case illustrates the advantage of the biplane transesophageal transducer, as the diagnosis would have been missed with a standard single plane probe.
transesophageal echocardiography, tricuspid vegetation, biplane transesophageal echocardiography