Browsing by Author "Ransohoff, David F."

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    Derivation and validation of a predictive model for advanced colorectal neoplasia in asymptomatic adults
    (BMJ, 2021) Imperiale, Thomas F.; Monahan, Patrick O.; Stump, Timothy E.; Ransohoff, David F.; Medicine, School of Medicine
    Objective Knowing risk for advanced colorectal neoplasia (AN) could help patients and providers choose among screening tests, improving screening efficiency and uptake. We created a risk prediction model for AN to help decide which test might be preferred, a use not considered for existing models. Design Average-risk 50-to-80-year olds undergoing first-time screening colonoscopy were recruited from endoscopy units in Indiana. We measured sociodemographic and physical features, medical and family history and lifestyle factors and linked these to the most advanced finding. We derived a risk equation on two-thirds of the sample and assigned points to each variable to create a risk score. Scores with comparable risks were collapsed into risk categories. The model and score were tested on the remaining sample. Results Among 3025 subjects in the derivation set (mean age 57.3 (6.5) years; 52% women), AN prevalence was 9.4%. The 13-variable model (c-statistic=0.77) produced three risk groups with AN risks of 1.5% (95% CI 0.72% to 2.74%), 7.06% (CI 5.89% to 8.38%) and 27.26% (CI 23.47% to 31.30%) in low-risk, intermediate-risk and high-risk groups (p value <0.001), containing 23%, 59% and 18% of subjects, respectively. In the validation set of 1475 subjects (AN prevalence of 8.4%), model performance was comparable (c-statistic=0.78), with AN risks of 2.73% (CI 1.25% to 5.11%), 5.57% (CI 4.12% to 7.34%) and 25.79% (CI 20.51% to 31.66%) in low-risk, intermediate-risk and high-risk subgroups, respectively (p<0.001), containing proportions of 23%, 59% and 18%. Conclusion Among average-risk persons, this model estimates AN risk with high discrimination, identifying a lower risk subgroup that may be screened non-invasively and a higher risk subgroup for which colonoscopy may be preferred. The model could help guide patient–provider discussions of screening options, may increase screening adherence and conserve colonoscopy resources.
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    Derivation and Validation of a Scoring System to Stratify Risk for Advanced Colorectal Neoplasia in Asymptomatic Adults: A Cross-sectional Study
    (American College of Physicians, 2015-09-01) Imperiale, Thomas F.; Monahan, Patrick O.; Stump, Timothy E.; Glowinski, Elizabeth A.; Ransohoff, David F.; Department of Medicine, IU School of Medicine
    BACKGROUND: Several methods are recommended equally strongly for colorectal cancer screening in average-risk persons. Risk stratification would enable tailoring of screening within this group, with less invasive tests (sigmoidoscopy or occult blood tests) for lower-risk persons and colonoscopy for higher-risk persons. OBJECTIVE: To create a risk index for advanced neoplasia (colorectal cancer and adenomas or serrated polyps ≥1.0 cm, villous histology, or high-grade dysplasia) anywhere in the colorectum, using the most common risk factors for colorectal neoplasia. DESIGN: Cross-sectional study. SETTING: Multiple endoscopy units, primarily in the Midwest. PATIENTS: Persons aged 50 to 80 years undergoing initial screening colonoscopy (December 2004 to September 2011). MEASUREMENTS: Derivation and validation of a risk index based on points from regression coefficients for age, sex, waist circumference, cigarette smoking, and family history of colorectal cancer. RESULTS: Among 2993 persons in the derivation set, prevalence of advanced neoplasia was 9.4%. Risks for advanced neoplasia in persons at very low, low, intermediate, and high risk were 1.92% (95% CI, 0.63% to 4.43%), 4.88% (CI, 3.79% to 6.18%), 9.93% (CI, 8.09% to 12.0%), and 24.9% (CI, 21.1% to 29.1%), respectively (P < 0.001). Sigmoidoscopy to the descending colon in the low-risk groups would have detected 51 of 70 (73% [CI, 61% to 83%]) advanced neoplasms. Among 1467 persons in the validation set, corresponding risks for advanced neoplasia were 1.65% (CI, 0.20% to 5.84%), 3.31% (CI, 2.08% to 4.97%), 10.9% (CI, 8.26% to 14.1%), and 22.3% (CI, 16.9% to 28.5%), respectively (P < 0.001). Sigmoidoscopy would have detected 21 of 24 (87.5% [CI, 68% to 97%]) advanced neoplasms. LIMITATIONS: Split-sample validation; results apply to first-time screening. CONCLUSION: This index stratifies risk for advanced neoplasia among average-risk persons by identifying lower-risk groups for which noncolonoscopy strategies may be effective and efficient and a higher-risk group for which colonoscopy may be preferred. PRIMARY FUNDING SOURCE: National Cancer Institute, Walther Cancer Institute, Indiana University Simon Cancer Center, and Indiana Clinical and Translational Sciences Institute.
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    New Scoring Systems for Predicting Advanced Proximal Neoplasia in Asymptomatic Adults With or Without Knowing Distal Colorectal Findings: A Prospective, Cross-sectional Study
    (Wolters Kluwer, 2022) Imperiale, Thomas F.; Monahan, Patrick O.; Stump, Timothy E.; Ransohoff, David F.; Medicine, School of Medicine
    Background: Models estimating risk for advanced proximal colorectal neoplasia (APN) may be used to select colorectal cancer (CRC) screening test, either prior to knowing distal colorectal findings or afterward. Current models have only fair discrimination and nearly all require knowing distal findings. Objective: Derive and test risk prediction models for APN with and without distal findings. Setting: Selected endoscopy centers within central Indiana, USA. Participants: Average-risk persons undergoing first-time screening colonoscopy. Interventions: Demographics, personal and family medical history, lifestyle factors and physical measures were linked to the most advanced finding in proximal and distal colorectal segments. For both models, logistic regression identified factors independently associated with APN on a derivation set. Based on equation coefficients, points were assigned to each factor, and risk for APN was examined for each score. Scores with comparable risks were collapsed into risk categories. Both models and their scoring systems were tested on the validation set. Main outcome: APN, defined as any adenoma or sessile serrated lesion ≥1 cm, one with villous histology or high-grade dysplasia, or CRC proximal to the descending colon. Results: Among 3025 subjects in the derivation set (mean age 57.3 ± 6.5 years; 52% women), APN prevalence was 4.5%; 2859 (94.5%) had complete data on risk factors. Independently associated with APN were age, sex, cigarette smoking, cohabitation status, metabolic syndrome, non-steroidal anti-inflammatory drug use and physical activity. This model (without distal findings) was well-calibrated (P = 0.62) and had good discrimination (c-statistic = 0.73). In low-, intermediate- and high-risk groups that comprised 21, 58 and 21% of the sample, respectively, APN risks were 1.47% (95% CI, 0.67-2.77%), 3.09% (CI, 2.31-4.04%) and 11.6% (CI, 9.10-14.4%), respectively (P < 0.0001), with no proximal CRCs in the low-risk group and 2 in the intermediate-risk group. When tested in the validation set of 1455, the model retained good metrics (calibration P = 0.85; c-statistic = 0.83), with APN risks in low- (22%), intermediate- (56%) and high-risk (22%) subgroups of 0.62% (CI, 0.08-2.23%) 2.20% (CI, 1.31-3.46%) and 13.0% (CI, 9.50-17.2%), respectively (P < 0.0001). There were no proximal CRCs in the low-risk group, and two in the intermediate-risk group. The model with distal findings performed comparably, with validation set metrics of 0.18 for calibration, 0.76 for discrimination and APN risk (% sample) in low-, intermediate-, and high-risk groups of 1.1 (69%), 8.3 (22%) and 22.3% (9%). Conclusion: These models stratify large proportions of average-risk persons into clinically meaningful risk groups, and could improve screening efficiency, particularly for noncolonoscopy-based programs.
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    Phenotypic features effectively stratify risk for advanced colorectal neoplasia in asymptomatic adults
    (Office of the Vice Chancellor for Research, 2015-04-17) Imperiale, Thomas F.; Monahan, Patrick O.; Stump, Timothy E.; Glowinski, Elizabeth A.; Ransohoff, David F.
    Background: While colorectal cancer (CRC) screening is effective and cost-effective for reducing CRC incidence and mortality, it is underutilized (nearly 40% of U.S. adults are either not current with or have never been screened), inefficient (low-risk persons undergo colonoscopy), and costly to the U.S. health care system. A simple and effective way of stratifying risk for advanced neoplasia (AN – CRC and advanced, precancerous polyps) could improve the efficiency and uptake of screening by tailoring colonoscopy toward persons at highrisk and giving low-risk persons less-invasive options. Although several risk factors for AN have been identified, they are not used in clinical practice in part because of inability to integrate the factors to produce a risk estimate. Objective: To derive and validate a risk index for AN (CRC, advanced adenomas, serrated polyps >= 1 cm) anywhere in the colorectum. Methods: We measured socio-demographic features, medical and family history, lifestyle factors, and physical features in 50-80 year old persons who underwent first-time screening colonoscopy between December 2004 and September 2011, and linked these factors to endoscopic and histologic findings. Using logistic regression, we derived a risk equation on a randomly selected 2/3s of the sample. A 12-variable model was selected based on optimal statistical metrics. Based on model coefficients, we assigned points to each variable to create a risk score, which ranged from -13 to 8. Scores with comparable magnitudes of risk were collapsed into 3 risk categories. The model was tested on the remaining third of the sample. Results: Among 3025 subjects in the derivation set (mean age 57.3 ± 6.5 years; 52% women), the prevalence of AN was 9.4% (including 26 CRCs). Model variables include age, sex, smoking, ethanol use, marital status, NSAID and aspirin use, physical activity, education level, and metabolic syndrome (P-value for fit = 0.09; cstatistic=0.78). Respective risks of AN in the low- (scores of -13 to -5), intermediate- (scores of -4 to 2) and high- (scores of 3 to 12) were 1.52% (95%, 0.07-2.8%), 6.86%, and 26.8% (P-value for trend < 0.001), with respective cohort proportions of 23%, 59% and 18%. Ten low-risk subjects had AN (0 CRCs, 6 distal). Based on finding a distal sentinel polyp, sigmoidoscopy to the descending colon would have detected 7(70%) ANs. Among the 1475 subjects in the test set (mean age 57.2 ± 6.5 years; 52% women), AN prevalence was 8.4%. Risk of AN in the low-risk subgroup was 2.73% (CI, 1.25-5.11%) and was 5.57% and 25.4% in the intermediate- and high-risk subgroups, respectively (P<0.001), with cohort proportions of 23%, 59%, and 18%. Nine low-risk subjects had AN (0 CRCs, 5 distal, 6 detectable by sigmoidoscopy. Conclusion: This new risk index effectively stratifies the risk for AN among asymptomatic adults, identifying a low-risk subgroup of 23% that may be screened effectively and efficiently with tests other than colonoscopy and a high-risk subgroup of 18% in which colonoscopy may be preferable. If validated in other settings, this index could increase both the efficiency and uptake of CRC screening.
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    Risk of Advanced Neoplasia Using the National Cancer Institute’s Colorectal Cancer Risk Assessment Tool
    (Oxford University Press, 2017-01) Imperiale, Thomas F.; Yu, Menggang; Monahan, Patrick O.; Stump, Timothy E.; Tabbey, Rebeka; Glowinski, Elizabeth; Ransohoff, David F.; Medicine, School of Medicine
    Background: There is no validated, discriminating, and easy-to-apply tool for estimating risk of colorectal neoplasia. We studied whether the National Cancer Institute’s (NCI’s) Colorectal Cancer (CRC) Risk Assessment Tool, which estimates future CRC risk, could estimate current risk for advanced colorectal neoplasia among average-risk persons. Methods: This cross-sectional study involved individuals age 50 to 80 years undergoing first-time screening colonoscopy. We measured medical and family history, lifestyle information, and physical measures and calculated each person’s future CRC risk using the NCI tool’s logistic regression equation. We related quintiles of future CRC risk to the current risk of advanced neoplasia (sessile serrated polyp or tubular adenoma ≥ 1 cm, a polyp with villous histology or high-grade dysplasia, or CRC). All statistical tests were two-sided. Results: For 4457 (98.5%) with complete data (mean age = 57.2 years, SD = 6.6 years, 51.7% women), advanced neoplasia prevalence was 8.26%. Based on quintiles of five-year estimated absolute CRC risk, current risks of advanced neoplasia were 2.1% (95% confidence interval [CI] = 1.3% to 3.3%), 4.8% (95% CI = 3.5% to 6.4%), 6.4% (95% CI = 4.9% to 8.2%), 10.0% (95% CI = 8.1% to 12.1%), and 17.6% (95% CI = 15.5% to 20.6%; P < .001). For quintiles of estimated 10-year CRC risk, corresponding current risks for advanced neoplasia were 2.2% (95% CI = 1.4% to 3.5%), 4.8% (95% CI = 3.5% to 6.4%), 6.5% (95% CI = 5.0% to 8.3%), 9.3% (95% CI = 7.5% to 11.4%), and 18.4% (95% CI = 15.9% to 21.1%; P < .001). Among persons with an estimated five-year CRC risk above the median, current risk for advanced neoplasia was 12.8%, compared with 3.7% among those below the median (relative risk = 3.4, 95 CI = 2.7 to 4.4). Conclusions: The NCI’s Risk Assessment Tool, which estimates future CRC risk, may be used to estimate current risk for advanced neoplasia, making it potentially useful for tailoring and improving CRC screening efficiency among average-risk persons.