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Robert E Schoen - One of the best experts on this subject based on the ideXlab platform.
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utilization and yield of surveillance colonoscopy in the continued follow up study of the polyp prevention trial
Clinical Gastroenterology and Hepatology, 2009Co-Authors: Adeyinka O Laiyemo, Paul F Pinsky, Pamela M Marcus, Elaine Lanza, Amanda J Cross, Arthur Schatzkin, Robert E SchoenAbstract:Background and Aims Prospective information on the use and yield of surveillance colonoscopy is limited. We examined the use and yield of surveillance colonoscopy among participants in the Polyp Prevention Trial (PPT) after the 4-year dietary intervention trial ended. Methods We followed a cohort of 1297 participants. We calculated the cumulative probability of posttrial colonoscopy and investigated the yield and predictive factors for Adenoma and advanced Adenoma recurrence over a mean time of 5.9 years. Results Seven-hundred seventy-four subjects (59.7%) had a repeat colonoscopy. Among 431 subjects with low-risk Adenomas (1–2 nonadvanced Adenomas) at baseline and no Adenoma recurrence at the end of the PPT (lowest-risk category), 30.3% underwent a repeat colonoscopy within 4 years. Among 55 subjects who had high-risk Adenomas (advanced Adenoma and/or ≥3 nonadvanced Adenomas) at baseline and again at the final PPT colonoscopy (highest-risk category), 41.3% had a colonoscopy within 3 years and 63.5% had an examination within 5 years. The cumulative yield of advanced Adenoma through 6 years was 3.6% for the lowest-risk category, 38.9% for the highest-risk category, and ranged from 6.6% to 13.8% for intermediate-risk categories. An advanced Adenoma at the final PPT colonoscopy was associated significantly with an advanced Adenoma recurrence during surveillance (hazard ratio, 6.2; 95% confidence interval, 2.5–15.4). Conclusions Surveillance colonoscopy was overused for low-risk subjects and underused for high-risk subjects. Advanced Adenoma yield corresponded with the Adenoma risk category. Resource consumption can be better managed by aligning use with the risk of Adenoma recurrence.
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is colonoscopy needed for the nonadvanced Adenoma found on sigmoidoscopy
Gastroenterology, 1998Co-Authors: Robert E Schoen, Peter Lance, Don Corle, Linda Cranston, Joel L Weissfeld, Randall W Burt, Frank L Iber, Moshe Shike, James W Kikendall, Marsha HassonAbstract:Abstract Background & Aims: The need for colonoscopy when small tubular Adenomas with low-grade dysplasia are found on sigmoidoscopy is uncertain. The aim of this study was to examine the prevalence and characteristics of proximal Adenomas in patients with distal Adenomas. Methods: We studied 981 subjects with distal Adenomas found on the index colonoscopy before randomization in the Polyp Prevention Trial. Results: Four hundred sixty patients (46.9%) had ≥1 distal Adenoma that was pathologically advanced (villous component, high-grade dysplasia, or ≥1 cm); 21.5% (211 of 981) had any proximal Adenoma; and 4.3% (42 of 981) (95% confidence interval [CI], 3.0–5.5) had an advanced proximal Adenoma. A greater percentage of patients with an advanced distal Adenoma (5.9%) (95% CI, 3.7–8.0) had an advanced proximal Adenoma compared with those with a nonadvanced distal Adenoma (2.9%) (95% CI, 1.4–4.3) (OR, 2.1; 95% CI, 1.1–4.3; P = 0.03). Not performing a colonoscopy in patients with a nonadvanced distal Adenoma would have missed 36% (15 of 42) of the advanced proximal Adenomas. Conclusions: Patients with an advanced distal Adenoma are twice as likely to have an advanced proximal Adenoma as patients with a nonadvanced distal Adenoma. However, eschewing a colonoscopy in patients with a nonadvanced distal Adenoma would result in not detecting a sizeable percentage of the prevalent advanced proximal Adenomas. These data support performance of a colonoscopy in patients with a nonadvanced distal Adenoma. Confirmation of these results in asymptomatic subjects undergoing screening sigmoidoscopy is advisable. GASTROENTEROLOGY 1998;115:533-541
Elaine Lanza - One of the best experts on this subject based on the ideXlab platform.
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utilization and yield of surveillance colonoscopy in the continued follow up study of the polyp prevention trial
Clinical Gastroenterology and Hepatology, 2009Co-Authors: Adeyinka O Laiyemo, Paul F Pinsky, Pamela M Marcus, Elaine Lanza, Amanda J Cross, Arthur Schatzkin, Robert E SchoenAbstract:Background and Aims Prospective information on the use and yield of surveillance colonoscopy is limited. We examined the use and yield of surveillance colonoscopy among participants in the Polyp Prevention Trial (PPT) after the 4-year dietary intervention trial ended. Methods We followed a cohort of 1297 participants. We calculated the cumulative probability of posttrial colonoscopy and investigated the yield and predictive factors for Adenoma and advanced Adenoma recurrence over a mean time of 5.9 years. Results Seven-hundred seventy-four subjects (59.7%) had a repeat colonoscopy. Among 431 subjects with low-risk Adenomas (1–2 nonadvanced Adenomas) at baseline and no Adenoma recurrence at the end of the PPT (lowest-risk category), 30.3% underwent a repeat colonoscopy within 4 years. Among 55 subjects who had high-risk Adenomas (advanced Adenoma and/or ≥3 nonadvanced Adenomas) at baseline and again at the final PPT colonoscopy (highest-risk category), 41.3% had a colonoscopy within 3 years and 63.5% had an examination within 5 years. The cumulative yield of advanced Adenoma through 6 years was 3.6% for the lowest-risk category, 38.9% for the highest-risk category, and ranged from 6.6% to 13.8% for intermediate-risk categories. An advanced Adenoma at the final PPT colonoscopy was associated significantly with an advanced Adenoma recurrence during surveillance (hazard ratio, 6.2; 95% confidence interval, 2.5–15.4). Conclusions Surveillance colonoscopy was overused for low-risk subjects and underused for high-risk subjects. Advanced Adenoma yield corresponded with the Adenoma risk category. Resource consumption can be better managed by aligning use with the risk of Adenoma recurrence.
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a pooled analysis of advanced colorectal neoplasia diagnoses after colonoscopic polypectomy
Gastroenterology, 2009Co-Authors: Maria Elena Martinez, Elaine Lanza, Arthur Schatzkin, Sidney J Winawer, Ann G Zauber, John A Baron, David A Lieberman, Ruiyun Jiang, Dennis J Ahnen, John H BondAbstract:Background & Aims Limited data exist regarding the actual risk of developing advanced Adenomas and cancer after polypectomy or the factors that determine risk. Methods We pooled individual data from 8 prospective studies comprising 9167 men and women aged 22 to 80 with previously resected colorectal Adenomas to quantify their risk of developing subsequent advanced Adenoma or cancer as well as identify factors associated with the development of advanced colorectal neoplasms during surveillance. Results During a median follow-up period of 47.2 months, advanced colorectal neoplasia was diagnosed in 1082 (11.8%) of the patients, 58 of whom (0.6%) had invasive cancer. Risk of a metachronous advanced Adenoma was higher among patients with 5 or more baseline Adenomas (24.1%; standard error, 2.2) and those with an Adenoma 20 mm in size or greater (19.3%; standard error, 1.5). Risk factor patterns were similar for advanced Adenomas and invasive cancer. In multivariate analyses, older age ( P P Conclusions Occurrence of advanced colorectal neoplasia is common after polypectomy. Factors that are associated most strongly with risk of advanced neoplasia are patient age and the number and size of prior Adenomas.
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gene specific methylation and subsequent risk of colorectal Adenomas among participants of the polyp prevention trial
Cancer Epidemiology Biomarkers & Prevention, 2005Co-Authors: Karen Woodson, Arthur Schatzkin, Daniel J Weisenberger, Mihaela Campan, Peter W Laird, Joseph A Tangrea, Laura Lee Johnson, Elaine LanzaAbstract:Hypermethylation of tumor suppressor and other regulatory genes is thought to play an important role in colorectal neoplasia and tumorigenesis. This study examined the association between gene methylation status in baseline Adenomas and subsequent Adenoma recurrence in a randomized dietary intervention study, the Polyp Prevention Trial. The methylation status of four genes [ CDKN2A ( p16 ), PTGS2 ( COX2 ), ESR1 ( ER-α ), and PGR ( PR )] was determined by MethyLight in 284 baseline Adenomas from 196 trial participants. The association of gene methylation with recurrence was determined using logistic regression models. Gene methylation was evaluated as percent of methylated reference, a measure of methylation of each gene relative to control DNA. ESR1 methylation status was inversely associated with Adenoma recurrence, odds ratio = 0.36 (95% confidence interval, 0.15-0.88; P = 0.02) for the highest compared with the lowest quartile of the ESR1 methylation. Further, ESR1 methylation status was inversely associated with the recurrence of multiple Adenomas, advanced Adenomas, and the recurrence of Adenomas in the proximal but not distal bowel. No association between CDKN2A , PTGS2 , or PGR methylation and Adenoma recurrence was observed. These data suggest that ESR1 methylation may play a role in subsequent Adenoma recurrence.
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hormone replacement therapy and colorectal Adenoma recurrence among women in the polyp prevention trial
Journal of the National Cancer Institute, 2001Co-Authors: Karen Woodson, Elaine Lanza, Paul S Albert, Bette J Caan, Frank L Iber, Joseph A Tangrea, Martha L Slattery, Joan Pinsky, Electra D Paskett, Walter J KikendallAbstract:BACKGROUND: Epidemiologic studies have suggested that estrogen may protect against the development of colorectal cancers and Adenomatous polyps. We conducted a prospective study to evaluate the association between hormone replacement therapy (HRT) and Adenoma recurrence among perimenopausal and postmenopausal women participating in the Polyp Prevention Trial, a randomized dietary intervention study of individuals with colorectal Adenomas. METHODS: We used a questionnaire and interviews to collect detailed information, at baseline and at each of four annual study visits, from 620 women regarding hormone use, menopausal status, diet, alcohol consumption, and other risk factors. Adenoma recurrence was ascertained by complete colonoscopy at baseline and after 1 and 4 years. Logistic regression models were used to evaluate the association between hormone use and Adenoma recurrence after adjusting for intervention group and for age and body mass index at baseline. All statistical tests were two-sided. RESULTS: Adenomas recurred in 200 women. There was no overall association between Adenoma recurrence and either overall hormone use (odds ratio [OR] = 1.01; 95% confidence interval [CI] = 0.70 to 1.45), combined estrogen and progestin use (OR = 0.94; 95% CI = 0.57 to 1.56), or unopposed estrogen use (OR = 1.04; 95% CI = 0.68 to 1.59). HRT use was associated with a reduction in risk for recurrence of distal Adenomas (OR = 0.56; 95% CI = 0.32 to 1.00) and a statistically nonsignificant increase in risk for recurrence of proximal Adenomas (OR = 1.39; 95% CI = 0.85 to 2.26). We observed a statistically significant interaction between the HRT-Adenoma recurrence association and age (P =.02). HRT was associated with a 40% reduced risk of Adenoma recurrence among women older than 62 years (OR = 0.58; 95% CI = 0.35 to 0.97) but with an increased risk among women younger than 62 years (OR = 1.99; 95% CI = 1.11 to 3.55). CONCLUSIONS: HRT was not associated with a reduced risk for overall Adenoma recurrence in this trial cohort, although there was a suggestion of an age interaction. The effect of age on the association needs to be confirmed in other Adenoma recurrence trials.
Claire Helbig - One of the best experts on this subject based on the ideXlab platform.
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high yields of small and flat Adenomas with high definition colonoscopes using either white light or narrow band imaging
Gastroenterology, 2007Co-Authors: Douglas K Rex, Claire HelbigAbstract:Background & Aims: Detection of Adenomas is an important goal of colonoscopy. Narrow band imaging (NBI) might highlight Adenomas and lead to higher rates of Adenoma detection. Methods: This was a randomized controlled trial of colonoscopy withdrawal in white light versus NBI in 434 patients aged 50 years or older with intact colons. All examinations were performed by a single experienced endoscopist with a known high detection rate of Adenomas using high-definition, wide-angle (170° field of view) colonoscopes. Results: There was no difference in the percent of patients with ≥1 Adenoma for the entire cohort in white light (67%) versus NBI (65%) (P = .61) or in the subset of 257 patients with indication screening (58% vs 57%; P = .91). Both the prevalences of Adenomas and the numbers of Adenomas per colonoscopy are the highest ever reported in colonoscopy studies. The high prevalence rates of Adenomas were accounted for by detection of large numbers of Adenomas, including flat Adenomas, which were ≤5 mm. Conclusions: NBI did not result in better detection of Adenomas by an endoscopist with a known high detection rate using white light. This result does not exclude a possible benefit of NBI in reducing variation between endoscopists in detection of Adenomas. The very high Adenoma detection rate in this study suggests that high definition should be directly tested for its effect on detection of Adenomas.
Amanda J Cross - One of the best experts on this subject based on the ideXlab platform.
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number of Adenomas removed and colorectal cancers prevented in randomized trials of flexible sigmoidoscopy screening
Gastroenterology, 2018Co-Authors: Paul F Pinsky, Amanda J Cross, Magnus Loberg, Carlo Senore, Kate Wooldrage, Wendy Atkin, Michael Bretthauer, Geir Hoff, Oyvind Holme, Mette KalagerAbstract:Background & Aims Screening for colorectal cancer (CRC) with sigmoidoscopy reduces CRC incidence by detecting and removing Adenomas. The number needed to screen is a measure of screening efficiency, but is not directly associated with Adenoma removal. We propose the following 2 new metrics for quantifying the relationship between Adenoma removal and CRC prevented: number of Adenomas needed to remove (NNR) and Adenoma dwell time avoided (DTA). Methods We collected data from 4 randomized trials of sigmoidoscopy screening (1 in the United States and 3 in Europe) to assess NNR and DTA. For each trial, NNR was computed as the number of Adenomas removed from subjects in the intervention group, divided by the number of CRCs prevented. DTA was computed similarly but taking into account the timing of Adenoma removal. Combined results across trials were assessed using standard meta-analytic techniques. Results The estimated NNR for the PLCO (Prostate, Lung, Colorectal and Ovarian) trial was 74 (95% confidence interval [CI], 56–110), for the NORCCAP (Norwegian Colorectal Cancer Prevention) trial was 71 (95% CI, 44–174), for the SCORE (Screening for Colon Rectum) trial was 27 (95% CI, 14–135), and for the UKFSST (UK Flexible Sigmoidoscopy Screening Trial) was 36 (95% CI, 28–52). The combined estimate (meta-analysis) of NNR was 52 (95% CI, 36–93) assuming heterogeneity (P for heterogeneity = .014). DTA estimates among trials ranged from 278 to 730 years, with a combined estimate of 500 (95% CI, 344–833) years assuming heterogeneity (P for heterogeneity = .035), or 2 CRC cases prevented per 1000 Adenoma dwell years avoided. The combined estimates of NNR and DTA restricted to advanced Adenomas were 13 (95% CI, 9–22) and 122 (95% CI, 90–190) years, respectively. Conclusions We collected data from 4 randomized trials of sigmoidoscopy screening for CRC to develop metrics of endoscopic efficiency, NNR and DTA, which are directly linked to Adenoma detection and removal. They can be used to compare screening among endoscopic modalities and to more precisely measure Adenoma to carcinoma transition rates.
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utilization and yield of surveillance colonoscopy in the continued follow up study of the polyp prevention trial
Clinical Gastroenterology and Hepatology, 2009Co-Authors: Adeyinka O Laiyemo, Paul F Pinsky, Pamela M Marcus, Elaine Lanza, Amanda J Cross, Arthur Schatzkin, Robert E SchoenAbstract:Background and Aims Prospective information on the use and yield of surveillance colonoscopy is limited. We examined the use and yield of surveillance colonoscopy among participants in the Polyp Prevention Trial (PPT) after the 4-year dietary intervention trial ended. Methods We followed a cohort of 1297 participants. We calculated the cumulative probability of posttrial colonoscopy and investigated the yield and predictive factors for Adenoma and advanced Adenoma recurrence over a mean time of 5.9 years. Results Seven-hundred seventy-four subjects (59.7%) had a repeat colonoscopy. Among 431 subjects with low-risk Adenomas (1–2 nonadvanced Adenomas) at baseline and no Adenoma recurrence at the end of the PPT (lowest-risk category), 30.3% underwent a repeat colonoscopy within 4 years. Among 55 subjects who had high-risk Adenomas (advanced Adenoma and/or ≥3 nonadvanced Adenomas) at baseline and again at the final PPT colonoscopy (highest-risk category), 41.3% had a colonoscopy within 3 years and 63.5% had an examination within 5 years. The cumulative yield of advanced Adenoma through 6 years was 3.6% for the lowest-risk category, 38.9% for the highest-risk category, and ranged from 6.6% to 13.8% for intermediate-risk categories. An advanced Adenoma at the final PPT colonoscopy was associated significantly with an advanced Adenoma recurrence during surveillance (hazard ratio, 6.2; 95% confidence interval, 2.5–15.4). Conclusions Surveillance colonoscopy was overused for low-risk subjects and underused for high-risk subjects. Advanced Adenoma yield corresponded with the Adenoma risk category. Resource consumption can be better managed by aligning use with the risk of Adenoma recurrence.
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postpolypectomy colonoscopy surveillance guidelines predictive accuracy for advanced Adenoma at 4 years
Annals of Internal Medicine, 2008Co-Authors: Adeyinka O Laiyemo, Pamela M Marcus, Amanda J Cross, Gwen Murphy, Paul S Albert, Leah B Sansbury, Zhuoqiao Wang, Bette J Caan, James R Marshall, Peter LanceAbstract:rence within 4 years of follow-up. The probability of advanced Adenoma recurrence was 0.09 (95% CI, 0.07 to 0.11) among patients with high-risk Adenomas at baseline and 0.05 (CI, 0.04 to 0.06) among those with low-risk Adenomas at baseline. The relative risk for advanced Adenoma recurrence for patients with high-risk Adenomas versus those with low-risk Adenomas at baseline was 1.68 (CI, 1.19 to 2.38) when advanced Adenoma recurrence was compared with no advanced Adenoma recurrence and 1.76 (CI, 1.26 to 2.46) when advanced Adenoma recurrence was compared with no Adenoma recurrence. The c-statistics for these 2 comparisons were 0.68 and 0.72, respectively. Limitation: Participants were self-selected and had restrictions on the degree of obesity. Conclusion: Although the risk for recurrence of advanced Adenoma within 4 years is greater for patients with high-risk Adenomas at baseline than for those with low-risk Adenomas, the discrimination of this risk stratification scheme is relatively low.
Adeyinka O Laiyemo - One of the best experts on this subject based on the ideXlab platform.
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utilization and yield of surveillance colonoscopy in the continued follow up study of the polyp prevention trial
Clinical Gastroenterology and Hepatology, 2009Co-Authors: Adeyinka O Laiyemo, Paul F Pinsky, Pamela M Marcus, Elaine Lanza, Amanda J Cross, Arthur Schatzkin, Robert E SchoenAbstract:Background and Aims Prospective information on the use and yield of surveillance colonoscopy is limited. We examined the use and yield of surveillance colonoscopy among participants in the Polyp Prevention Trial (PPT) after the 4-year dietary intervention trial ended. Methods We followed a cohort of 1297 participants. We calculated the cumulative probability of posttrial colonoscopy and investigated the yield and predictive factors for Adenoma and advanced Adenoma recurrence over a mean time of 5.9 years. Results Seven-hundred seventy-four subjects (59.7%) had a repeat colonoscopy. Among 431 subjects with low-risk Adenomas (1–2 nonadvanced Adenomas) at baseline and no Adenoma recurrence at the end of the PPT (lowest-risk category), 30.3% underwent a repeat colonoscopy within 4 years. Among 55 subjects who had high-risk Adenomas (advanced Adenoma and/or ≥3 nonadvanced Adenomas) at baseline and again at the final PPT colonoscopy (highest-risk category), 41.3% had a colonoscopy within 3 years and 63.5% had an examination within 5 years. The cumulative yield of advanced Adenoma through 6 years was 3.6% for the lowest-risk category, 38.9% for the highest-risk category, and ranged from 6.6% to 13.8% for intermediate-risk categories. An advanced Adenoma at the final PPT colonoscopy was associated significantly with an advanced Adenoma recurrence during surveillance (hazard ratio, 6.2; 95% confidence interval, 2.5–15.4). Conclusions Surveillance colonoscopy was overused for low-risk subjects and underused for high-risk subjects. Advanced Adenoma yield corresponded with the Adenoma risk category. Resource consumption can be better managed by aligning use with the risk of Adenoma recurrence.
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postpolypectomy colonoscopy surveillance guidelines predictive accuracy for advanced Adenoma at 4 years
Annals of Internal Medicine, 2008Co-Authors: Adeyinka O Laiyemo, Pamela M Marcus, Amanda J Cross, Gwen Murphy, Paul S Albert, Leah B Sansbury, Zhuoqiao Wang, Bette J Caan, James R Marshall, Peter LanceAbstract:rence within 4 years of follow-up. The probability of advanced Adenoma recurrence was 0.09 (95% CI, 0.07 to 0.11) among patients with high-risk Adenomas at baseline and 0.05 (CI, 0.04 to 0.06) among those with low-risk Adenomas at baseline. The relative risk for advanced Adenoma recurrence for patients with high-risk Adenomas versus those with low-risk Adenomas at baseline was 1.68 (CI, 1.19 to 2.38) when advanced Adenoma recurrence was compared with no advanced Adenoma recurrence and 1.76 (CI, 1.26 to 2.46) when advanced Adenoma recurrence was compared with no Adenoma recurrence. The c-statistics for these 2 comparisons were 0.68 and 0.72, respectively. Limitation: Participants were self-selected and had restrictions on the degree of obesity. Conclusion: Although the risk for recurrence of advanced Adenoma within 4 years is greater for patients with high-risk Adenomas at baseline than for those with low-risk Adenomas, the discrimination of this risk stratification scheme is relatively low.