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Browsing by Subject "colorectal neoplasia"
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Item Performance Characteristics of Fecal Immunochemical Tests for Colorectal Cancer and Advanced Adenomatous Polyps: A Systematic Review and Meta-analysis(ACP, 2019-03) Imperiale, Thomas F.; Gruber, Rachel N.; Stump, Timothy E.; Emmett, Thomas; Monahan, Patrick O.; Medicine, School of MedicineBackground: Studies report inconsistent performance of fecal immunochemical tests (FITs) for colorectal cancer (CRC) and advanced adenomas. Purpose: To summarize performance characteristics of FITs for CRC and advanced adenomas in average-risk persons undergoing screening colonoscopy (reference standard) and to identify factors affecting these characteristics. Data Sources: Ovid MEDLINE, PubMed, Embase, and the Cochrane Library from inception through October 2018; reference lists of studies and reviews. Study Selection: Two reviewers independently screened records to identify published English-language prospective or retrospective observational studies that evaluated FIT sensitivity and specificity for colonoscopic findings in asymptomatic, average-risk adults. Data Extraction: Two authors independently extracted data and evaluated study quality. Data Synthesis: Thirty-one studies (120 255 participants; 18 FITs) were included; all were judged to have low to moderate risk of bias. Performance characteristics depended on the threshold for a positive result. A threshold of 10 µg/g resulted in sensitivity of 0.91 (95% CI, 0.84 to 0.95) and a negative likelihood ratio of 0.10 (CI, 0.06 to 0.19) for CRC, whereas a threshold of greater than 20 µg/g resulted in specificity of 0.95 (CI, 0.94 to 0.96) and a positive likelihood ratio of 15.49 (CI, 9.82 to 22.39). For advanced adenomas, sensitivity was 0.40 (CI, 0.33 to 0.47) and the negative likelihood ratio was 0.67 (CI, 0.57 to 0.78) at 10 µg/g, and specificity was 0.95 (CI, 0.94 to 0.96) and the positive likelihood ratio was 5.86 (CI, 3.77 to 8.97) at greater than 20 µg/g. Studies had low to high heterogeneity, depending on the threshold. Although several FITs had adequate performance, sensitivity and specificity for CRC for 1 qualitative FIT were 0.90 and 0.91, respectively, at its single threshold of 10 µg/g; positive and negative likelihood ratios were 10.13 and 0.11, respectively. Comparison of 3 FITs at 3 thresholds was inconclusive: CIs overlapped, and the comparisons were across rather than within studies. Limitations: Only English-language studies were included. Incomplete reporting limited quality assessment of some evidence. Performance characteristics are for 1-time rather than serial testing. Conclusion: Single-application FITs have moderate to high sensitivity and specificity for CRC, depending on the positivity threshold. Sensitivity of 1-time testing for advanced adenomas is low, regardless of the threshold.Item Tailoring Surveillance Colonoscopy in Patients with Advanced Adenomas(Elsevier, 2021) Kahi, Charles J.; Myers, Laura J.; Stump, Timothy E.; Imler, Timothy D.; Sherer, Eric A.; Larson, Jason; Imperiale, Thomas F.; Medicine, School of MedicineBackground and Aims Patients with advanced colorectal adenomas (AA) are directed to undergo intensive surveillance. However, the benefit derived from surveillance may be outweighed by the risk of death from non-colorectal cancer (CRC) causes, leading to uncertainty on how best to individualize follow-up. The aim of this study was to derive a risk prediction model and risk index that estimates and stratifies the risk for non-colorectal cancer mortality (NCM) subsequent to diagnosis and removal of AA. Methods We conducted a retrospective cohort study of Veterans > 40 years who had colonoscopy for diagnostic or screening indications at 13 VAMCs between 2002 and 2009, and had one or more AAs. The primary outcome was non-CRC mortality (NCM) using a fixed follow-up time period of 5 years. Logistic regression using the lasso technique was used to identify factors independently associated with non-CRC mortality (NCM), and an index based on points from regression coefficients was constructed to estimate risk of 5-year NCM. Results We identified 2,943 Veterans with AA (mean age (SD) 63 (8.6) years, 98% male, 74% white), with an overall 5-year mortality of 16.7%, which was nearly all due to NCM (16.6%). Age, comorbidity burden, specific comorbid conditions, and hospitalization within the preceding year were independently associated with NCM. The risk prediction model had a goodness of fit (calibration) p-value of 0.41, and c-statistic (discrimination) of 0.74 (95% CI, 0.71-0.76). Based on comparable 5-year risks of NCM, the scores comprised 3 risk categories: low (score of 0-1), intermediate (score of 2-4) and high (score of ≥ 5), in which NCM occurred in 6.5%, 14.1%, and 33.2%, respectively. Conclusions We derived a risk prediction model that identifies Veterans at high risk of NCM within 5 years, and who are thus unlikely to benefit from further surveillance.