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Rex, Douglas K.

https://orcid.org/0000-0002-9836-4309

Mayo Clinic

Indiana University School of Medicine

Citations 22

Expert endoscopist assessment of colorectal polyp size using virtual scale endoscopy, visual or snare-based estimation: a prospective video-based study
Crainic, Ioana Popescu, Rex, Douglas K. , Hassan, Cesare , Pohl, Heiko , Rastogi, Amit, Anderson, Joseph C. , Taghiakbari, Mahsa , Medawar, Edgard , Renteln, Daniel von , East, James, Hassan, Cesare , Djinbachian, Roupen , Barkun, Alan , Shaukat, Aasma , East, James E. , Mori, Yuichi , Sharma, Prateek

Scandinavian Journal of Gastroenterology | February 9, 2024 | Volume: 59 | Issue: 5 | Pages: 608-614

10.1080/00365521.2024.2308519 Get It

Comparing margin ablation techniques after endoscopic mucosal resection of large nonpedunculated colorectal polyps
Pohl, Heiko , Rex, Douglas K. , Levenick, John M. , Khashab, Mouen A. , Melson, Joshua , Gavrić, Aleksandar , Daniel, Valérie, Djinbachian, Roupen , Pleskow, Douglas K. , Wallace, Michael B. , Singh, Ameet , Yang, Dennis J. , Daniel, V. R.

Endoscopy | November 9, 2023 | Volume: 55 | Issue: S 02 | Pages: S258-S258

10.1055/s-0043-1765703 Get It

Thermal ablation after endoscopic mucosal resection of large colorectal polyps: not only the margins, but also the base?
Djinbachian, Roupen , Pohl, Heiko , Rex, Douglas K. , Levenick, John M. , Wallace, Michael B. , Khashab, Mouen A., Singh, Ajaypal , Melson, Joshua , Gavrić, Aleksandar , Renteln, Daniel von , Ichkhanian, Yervant , Khashab, Mouen , von Renteln, Daniel , Wallace, Michael B , Djinbachian, Roupen , Pleskow, Douglas K. , Khashab, Mouen A. , Yang, Dennis J.

Gut | October 10, 2023 | Volume: 73 | Issue: 1 | Pages: 12-15

10.1136/gutjnl-2023-331057 Get It

Benefits and challenges in implementation of artificial intelligence in colonoscopy: World Endoscopy Organization position statement
Hassan, Cesare , Halvorsen, Natalie , Berzin, Tyler M. , Renteln, Daniel von , Hewett, David G. , Repici, Alessandro , Ramchandani, Mohan , Khatry, Maryam Al , Yu, Honggang , Saito, Yutaka , Misawa, Masashi , Parasa, Sravanthi , Matsubayashi, Carolina Ogawa , Ogata, Haruhiko , Tajiri, Hisao, Ahmad, Omer F. , Rex, Douglas K. , Berzin, Tyler M , Hewett, David G , Wang, Pu , Saito, Yutaka , Misawa, Masashi , Matsubayashi, Carolina Ogawa , Hassan, Cesare , Mori, Yuichi , East, James E. , Byrne, Michael F. , Kudo, Shin‐ei , Wang, Pu , Pausawasdi, Nonthalee , Dekker, Evelien , Sharma, Prateek

Digestive Endoscopy | February 7, 2023 | Volume: 35 | Issue: 4 | Pages: 422-429

10.1111/den.14531 Get It

The number of artificial intelligence (AI) tools for colonoscopy on the market is increasing with supporting clinical evidence. Nevertheless, their implementation is not going smoothly for a variety of reasons, including lack of data on clinical benefits and cost‐effectiveness, lack of trustworthy guidelines, uncertain indications, and cost for implementation. To address this issue and better guide practitioners, the World Endoscopy Organization (WEO) has provided its perspective about the status of AI in colonoscopy as the position statement. WEO Position Statement: Statement 1.1: Computer‐aided detection (CADe) for colorectal polyps is likely to improve colonoscopy effectiveness by reducing adenoma miss rates and thus increase adenoma detection; Statement 1.2: In the short term, use of CADe is likely to increase health‐care costs by detecting more adenomas; Statement 1.3: In the long term, the increased cost by CADe could be balanced by savings in costs related to cancer treatment (surgery, chemotherapy, palliative care) due to CADe‐related cancer prevention; Statement 1.4: Health‐care delivery systems and authorities should evaluate the cost‐effectiveness of CADe to support its use in clinical practice; Statement 2.1: Computer‐aided diagnosis (CADx) for diminutive polyps (≤5 mm), when it has sufficient accuracy, is expected to reduce health‐care costs by reducing polypectomies, pathological examinations, or both; Statement 2.2: Health‐care delivery systems and authorities should evaluate the cost‐effectiveness of CADx to support its use in clinical practice; Statement 3: We recommend that a broad range of high‐quality cost‐effectiveness research should be undertaken to understand whether AI implementation benefits populations and societies in different health‐care systems.
Survey Finds Gender Disparities Impact Both Women Mentors and Mentees in Gastroenterology
Rabinowitz, Loren , Zylberberg, Haley M. , Dixon, Rebekah E. , David, Yakira , Aroniadis, Olga C. , Chiang, Austin L. , Christie, Jennifer, Fayad, Nabil , Ha, Christina , Harris, Lucinda A. , Ko, Cynthia W. , Kwah, Joann , Raffals, Laura E. , Rex, Douglas K. , Siddiqui, Uzma D. , Smith, Michael S. , Wallace, Michael B. , Woods, Karen, Crowe, Sheila E., Kumta, Nikhil A. , Kim, Michelle Kang , Greenwald, David A. , Fichera, Alessandro , Wallace, Michael B , Grinspan, Lauren Tal , Kolb, Jennifer M. , Lee, Linda , Lieberman, David A. , Shah, Shailja C. , Williams, Reneé

American Journal of Gastroenterology | June 18, 2021 | Volume: 116 | Issue: 9 | Pages: 1876-1884

10.14309/ajg.0000000000001341 Get It

INTRODUCTION: Gastroenterologists at all levels of practice benefit from formal mentoring. Much of the current literature on mentoring in gastroenterology is based on expert opinion rather than data. In this study, we aimed to identify gender-related barriers to successful mentoring relationships from the mentor and mentee perspectives. METHODS: A voluntary, web-based survey was distributed to physicians at 20 academic institutions across the United States. Overall, 796 gastroenterology fellows and faculty received the survey link, with 334 physicians responding to the survey (42% response rate), of whom 299 (90%; 129 women and 170 men) completed mentorship questions and were included in analysis. RESULTS: Responses of women and men were compared. Compared with men, more women preferred a mentor of the same gender (38.6% women vs 4.2% men, P < 0.0001) but less often had one (45.5% vs 70.2%, P < 0.0001). Women also reported having more difficulty finding a mentor (44.4% vs 16.0%, P < 0.0001) and more often cited inability to identify a mentor of the same gender as a contributing factor (12.8% vs 0.9%, P = 0.0004). More women mentors felt comfortable advising women mentees about work-life balance (88.3% vs 63.8%, P = 0.0005). Nonetheless, fewer women considered themselves effective mentors (33.3% vs 52.6%, P = 0.03). More women reported feeling pressured to mentor because of their gender (39.5% vs 0.9% of men, P < 0.0001). Despite no gender differences, one-third of respondents reported negative impact of the COVID-19 pandemic on their ability to mentor and be mentored. DISCUSSION: Inequities exist in the experiences of women mentees and mentors in gastroenterology, which may affect career advancement and job satisfaction.
External validation of blue light imaging (BLI) criteria for the optical characterization of colorectal polyps by endoscopy experts
Desai, Madhav , Kennedy, Kevin F. , Aihara, Hiroyuki , Dam, Jacques Van, Gross, Seth A. , Haber, Gregory , Pohl, Heiko , Rex, Douglas K. , Saltzman, John R. , Sethi, Amrita , Waxman, Irving , Wallace, Michael B. , Repici, Alessandro , Wallace, Michael B , Wang, Kenneth , Sharma, Prateek

Journal of Gastroenterology and Hepatology | April 30, 2021 | Volume: 36 | Issue: 10 | Pages: 2728-2734

10.1111/jgh.15529 Get It

AbstractBackground and AimRecently, the BLI Adenoma Serrated International Classification (BASIC) system was developed by European experts to differentiate colorectal polyps. Our aim was to validate the BASIC classification system among the US‐based endoscopy experts.MethodsParticipants utilized a web‐based interactive learning system where the group was asked to characterize polyps using the BASIC criteria: polyp surface (presence of mucus, regular/irregular and [pseudo]depressed), pit appearance (featureless, round/non‐round with/without dark spots; homogeneous/heterogeneous distribution with/without focal loss), and vessels (present/absent, lacy, peri‐cryptal, irregular). The final testing consisted of reviewing BLI images/videos to determine whether the criteria accurately predicted the histology results. Confidence in adenoma identification (rated “1” to “5”) and agreement in polyp (adenoma vs non‐adenoma) identification and characterization per BASIC criteria were derived. Strength of interobserver agreement with kappa (k) value was reported for adenoma identification.ResultsTen endoscopy experts from the United States identified conventional adenoma (vs non‐adenoma) with 94.4% accuracy, 95.0% sensitivity, 93.8% specificity, 93.8% positive predictive value, and 94.9% negative predictive value using BASIC criteria. Overall strength of interobserver agreement was high: kappa 0.89 (0.82–0.96). Agreement for the individual criteria was as follows: surface mucus (93.8%), regularity (65.6%), type of pit (40.6%), pit visibility (66.9%), pit distribution (57%), vessel visibility (73%), and being lacy (46%) and peri‐cryptal (61%). The confidence in diagnosis was rated at high ≥4 in 67% of the cases.ConclusionsA group of US‐based endoscopy experts have validated a simple and easily reproducible BLI classification system to characterize colorectal polyps with >90% accuracy and a high level of interobserver agreement.
Multicentre, prospective, randomised study comparing the diagnostic yield of colon capsule endoscopy versus CT colonography in a screening population (the TOPAZ study)
Cash, Brooks D. , Fleisher, Mark R., Fern, Steven E., Rajan, Elizabeth , Haithcock, Robyn, Pound, David, Papageorgiou, Neofytos , Fernández-Urién, Ignacio , Schmelkin, Ira, Rex, Douglas K. , Kastenberg, David

Gut | December 23, 2020 | Volume: 70 | Issue: 11 | Pages: 2115-2122

10.1136/gutjnl-2020-322578 Get It

Objective Colon capsule endoscopy (CCE) has shown promise for colorectal neoplasia detection compared with optical colonoscopy (OC), but has not been compared with other screening tests in average risk screening patients. Design Patients 50 to 75 years of age (African Americans, 45–75 years) were randomised to CCE or CT colonography (CTC) and subsequent blinded OC. The primary endpoint was diagnostic yield of polyps ≥6 mm with CCE or CTC. Secondary endpoints included accuracy for size and histology, examination completeness, number/proportion of subjects with polyps and adenomas ≥6 mm and ≥10 mm, subject satisfaction and safety. Results From 320 enrolled subjects, data from 286 (89.4%) were evaluable. The proportion of subjects with any polyp ≥6 mm confirmed by OC was 31.6% for CCE versus 8.6% for CTC (pPr non-inferiority and superiority=0.999). The diagnostic yield of polyps ≥10 mm was 13.5% with CCE versus 6.3% with CTC (pPr non-inferiority=0.9954). The sensitivity and specificity of CCE for polyps ≥6 mm was 79.2% and 96.3% while that of CTC was 26.8% and 98.9%. The sensitivity and specificity of CCE for polyps ≥10 mm was 85.7% and 98.2% compared with 50% and 99.1% for CTC. Both tests were well tolerated/safe. Conclusion CCE was superior to CTC for detection of polyps ≥6 mm and non-inferior for identification of polyps ≥10 mm. CCE should be considered comparable or superior to CTC as a colorectal neoplasia screening test, although neither test is as effective as OC. Trial registration number ClinicalTrials.gov no: NCT02754661 .
Factors associated with complete clip closure after endoscopic mucosal resection of large colorectal polyps
Pohl, Heiko , Ortíz, Oswaldo , Rex, Douglas K. , Moyer, Matthew T. , Hasan, Muhammad K. , Pleskow, Douglas K. , Elmunzer, B. Joseph , Khashab, Mouen A., Al-Kawas, Fíras H. , Gordon, Stuart R. , Abraham, Mathew , Levenick, John M. , Aslanian, Harry R., Renteln, Daniel von , Rastogi, Amit , Gill, Jeffrey, Law, Ryan , Wallace, Michael B. , Elias, Pooja A., MacKenzie, Todd A. , Ortiz, Oswaldo , Pleskow, Douglas , Antaki, Fadi , von Renteln, Daniel , Wallace, Michael B , Pellisé, Maria , Grimm, Ian S. , Khashab, Mouen A. , Sanaei, Omid , Mathew, Abraham, Crockett, Seth D.

Endoscopy | December 9, 2020 | Volume: 53 | Issue: 11 | Pages: 1150-1159

10.1055/a-1332-6727 Get It

Abstract Background and study aim Delayed bleeding is a common adverse event following endoscopic mucosal resection (EMR) of large colorectal polyps. Prophylactic clip closure of the mucosal defect after EMR of nonpedunculated polyps larger than 20 mm reduces the incidence of severe delayed bleeding, especially in proximal polyps. This study aimed to evaluate factors associated with complete prophylactic clip closure of the mucosal defect after EMR of large polyps. Methods This is a post hoc analysis of the CLIP study (NCT01936948). All patients randomized to the clip group were included. Main outcome was complete clip closure of the mucosal resection defect. The defect was considered completely closed when no remaining mucosal defect was visible and clips were less than 1 cm apart. Factors associated with complete closure were evaluated in multivariable analysis. Results In total, 458 patients (age 65, 58 % men) with 494 large polyps were included. Complete clip closure of the resection defect was achieved for 338 polyps (68.4 %); closure was not complete for 156 (31.6 %). Factors associated with complete closure in adjusted analysis were smaller polyp size (odds ratio 1.06 for every millimeter decrease [95 % confidence interval 1.02–1.08]), good access (OR 3.58 [1.94–9.59]), complete submucosal lifting (OR 2.28 [1.36–3.90]), en bloc resection (OR 5.75 [1.48–22.39]), and serrated histology (OR 2.74 [1.35–5.56]). Conclusions Complete clip closure was not achieved for almost one in three resected large nonpedunculated polyps. While stable access and en bloc resection facilitate clip closure, most factors associated with clip closure are not modifiable. This highlights the need for alternative closure options and measures to prevent bleeding.
Shifts in the Fecal Microbiota Associated with Adenomatous Polyps
Hale, Vanessa L. , Johnson, Stephen , Harrington, Sean C., Yab, Tracy C. , Smyrk, Thomas C. , Nelson, Heidi , Boardman, Lisa A., Druliner, Brooke R., Levin, Theodore R. , Rex, Douglas K. , Ahnen, Dennis J. , Lance, Peter , Ahlquist, David A. , Chia, Nicholas , Chen, Jun , Boardman, Lisa A., Druliner, Brooke R. , Chia, Nicholas

Cancer Epidemiology, Biomarkers & Prevention | September 26, 2016 | Volume: 26 | Issue: 1 | Pages: 85-94

10.1158/1055-9965.epi-16-0337 Get It

Abstract Background: Adenomatous polyps are the most common precursor to colorectal cancer, the second leading cause of cancer-related death in the United States. We sought to learn more about early events of carcinogenesis by investigating shifts in the gut microbiota of patients with adenomas. Methods: We analyzed 16S rRNA gene sequences from the fecal microbiota of patients with adenomas (n = 233) and without (n = 547). Results: Multiple taxa were significantly more abundant in patients with adenomas, including Bilophila, Desulfovibrio, proinflammatory bacteria in the genus Mogibacterium, and multiple Bacteroidetes species. Patients without adenomas had greater abundances of Veillonella, Firmicutes (Order Clostridia), and Actinobacteria (family Bifidobacteriales). Our findings were consistent with previously reported shifts in the gut microbiota of colorectal cancer patients. Importantly, the altered adenoma profile is predicted to increase primary and secondary bile acid production, as well as starch, sucrose, lipid, and phenylpropanoid metabolism. Conclusions: These data hint that increased sugar, protein, and lipid metabolism along with increased bile acid production could promote a colonic environment that supports the growth of bile-tolerant microbes such as Bilophilia and Desulfovibrio. In turn, these microbes may produce genotoxic or inflammatory metabolites such as H2S and secondary bile acids, which could play a role in catalyzing adenoma development and eventually colorectal cancer. Impact: This study suggests a plausible biological mechanism to explain the links between shifts in the microbiota and colorectal cancer. This represents a first step toward resolving the complex interactions that shape the adenoma–carcinoma sequence of colorectal cancer and may facilitate personalized therapeutics focused on the microbiota. Cancer Epidemiol Biomarkers Prev; 26(1); 85–94. ©2016 AACR.