Retrograde inspection vs standard forward view for the detection of colorectal adenomas during colonoscopy: A back-to-back randomized clinical trial

BACKGROUND The adenoma detection rate(ADR) is inversely associated with the incidence of interval colorectal cancer and serves as a benchmark quality criterion during screening colonoscopy. However, adenoma miss rates reach up to 26% and studies have shown that a second inspection of the right colon in retroflected view(RFV) can increase ADR.AIM To assess whether inspection of the whole colon in RFV compared to standard forward view(SFV) can increase ADR.METHODS Patients presenting for screening or surveillance colonoscopy were invited to participate in this randomized controlled trial and randomized into two arms. In RFV arm colonoscopy was initially performed with SFV, followed by a second inspection of the whole colon in RFV. In the SFV arm first withdrawal was performed with SFV, followed by a second inspection of the whole colon again with SFV. Number, size and morphology of polyps found during first and second inspection in each colonic segment were recorded and all polyps were removed and sent for histopathology in separate containers.RESULTS Two hundred and five patients were randomly assigned to the RFV(n = 101) and SFV(n = 104) arm. In the RFV arm, both polyp detection rate(PDR) and ADR were increased under second inspection in RFV(PDR 1~(st) SFV: 39.8%, PDR 2~(nd)RFV: 46.6%; ADR 1~(st) SFV: 35.2%, ADR 2~(nd) RFV: 42%). Likewise, in the SFV arm,PDR and ADR were increased under second inspection(PDR 1~(st) SFV: 37.5%, PDR 2~(nd) SFV: 46.6%; ADR 1~(st) SFV: 34.1%, ADR 2~(nd)SFV: 44.3%) with no significant differences in ADR and PDR between the SFV and RFV arm. Mean number of adenomas per patient(APP) was increased in the RFV and SFV(APP RFV arm: 1~(st) SFV: 1.71; 2~(nd) RFV: 2.38; APP SFV arm: 1~(st) SFV: 1.83, 2~(nd)SFV:2.2). The majority of adenomas additionally found during second inspection in RFV or in SFV were located in the transverse and left-sided colon and were 5 mm in size.CONCLUSION Second inspection of the whole colon leads to increased adenoma detection with no differences between SFV and RFV. Hence, increased detection is most likely a feature of the second inspection itself but not of the inspection mode.     

Positive predictive value of fecal immunochemical test for high-risk colonic adenomas and carcinoma: A health maintenance organization cohort screening study in Lebanon

Background and Study AimsFecal Immunochemical Test (FIT) is one of the leading modalities for colorectal cancer screening. Studies show that FIT is highly sensitive for the detection of colorectal cancer (CRC) but not similarly accurate for detection of pre-cancerous advanced adenomas (AA). We studied the performance metrics of FIT for the detection of CRC and AA in a health maintenance organization (HMO) cohort screening program.Patients and MethodsRetrospective cohort study of asymptomatic persons of screening age belonging to a HMO. Endoscopy and pathology reports of those who tested positive were used to calculate the positive predictive value (PPV) of FIT, and characterize endoscopic findings on colonoscopy.ResultsBetween 1995 and 2017, 3000 persons had screening fecal occult testing as part of their Employee Health Care plan. Of those, 150 had a positive qualitative FIT (cutoff 10 Âµg hemoglobin/g feces). All underwent colonoscopy, and median time to colonoscopy was 27 days. 4 (2.6%) had carcinoma (2 stage IIIA and 2 stage IIIB), 106 (70.6%) had adenomas of which 40 (26.6% of the total cohort) had advanced adenomas (≥1 cm, villous features, or high-grade dysplasia) giving a PPV for AA and carcinoma of 29% and 3% respectively. When stratified by age, the PPV of AA; carcinoma was [50–59 (21.7%; 0.0%)], [60–69 (14.6%; 4.2%)], [70–79 (42.6%; 2.1%)], [80–89 (33.3%; 11.1%)].ConclusionThe performance characteristics of FIT testing are acceptable for population screening in resource-limited settings. The results of this study are helpful when discussing expectations prior to colonoscopy in people with positive FIT.     

Measuring the Quality of Colorectal Cancer Screening: The Importance of Follow-Up

Purpose As evidence mounts for effectiveness, an increasing proportion of the United States population undergoes colorectal cancer screening. However, relatively little is known about rates of follow-up after abnormal results from initial screening tests. This study examines patterns of colorectal cancer screening and follow-up within the nation's largest integrated health care system: the Veterans Health Administration. Methods We obtained information about patients who received colorectal cancer screening in the Veterans Health Administration from an existing quality improvement program and from the Veterans Health Administration's electronic medical record. Linking these data, we analyzed receipt of screening and follow-up testing after a positive fecal occult blood test. Results A total of 39,870 patients met criteria for colorectal cancer screening; of these 61 percent were screened. Screening was more likely in patients aged 70 to 80 years than in those younger or older. Female gender (relative risk, 0.92; 95 percent confidence interval, 0.9–0.95), Black race (relative risk, 0.92; 95 percent confidence interval, 0.89–0.96), lower income, and infrequent primary care visits were associated with lower likelihood of screening. Of those patients with a positive fecal occult blood test (n = 313), 59 percent received a follow-up barium enema or colonoscopy. Patient-level factors did not predict receipt of a follow-up test. Conclusions The Veterans Health Administration rates for colorectal cancer screening are significantly higher than the national average. However, 41 percent of patients with positive fecal occult blood tests failed to receive follow-up testing. Efforts to measure the quality of colorectal cancer screening programs should focus on the entire diagnostic process. Supported by the Robert Wood Johnson Foundation Clinical Scholars Program (Etzioni), Department of Veterans Affairs (VA) Health Services Research and Development (HSR&D), and National Cancer Institute Colorectal Cancer (CRC) Quality Enhancement Research Initiative (QUERI) Service Directed Research (Project # CRS 02-163). The views expressed in this article are those of the authors and do not necessarily represent the views of the Robert Wood Johnson Foundation or the Department of Veterans Affairs.