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Wallace, Michael B

0000-0002-6446-5785

Mayo Clinic

Mayo Clinic in Florida

Citations 91

Development of a stratification tool to identify pancreatic intraductal papillary mucinous neoplasms at lowest risk of progression
Overbeek, Kasper A. , Alblas, Maaike , Gausman, Valerie , Kandel, Pujan , Schweber, Adam B. , Brooks, Christian , Riet, Priscilla A. van , Wallace, Michael B. , Gonda, Tamas A. , Cahen, Djuna L. , Bruno, Marco J. , Van Riet, Priscilla A , Wallace, Michael B

Alimentary Pharmacology & Therapeutics | August 20, 2019 | Volume: 50 | Issue: 7 | Pages: 789-799

10.1111/apt.15440 Get It

SummaryBackgroundBecause most pancreatic intraductal papillary mucinous neoplasms (IPMNs) will never become malignant, currently advocated long‐term surveillance is low‐yield for most individuals.AimTo develop a score chart identifying IPMNs at lowest risk of developing worrisome features or high‐risk stigmata.MethodsWe combined prospectively maintained pancreatic cyst surveillance databases of three academic institutions. Patients were included if they had a presumed side‐branch IPMN, without worrisome features or high‐risk stigmata at baseline (as defined by the 2012 international Fukuoka guidelines), and were followed ≥ 12 months. The endpoint was development of one or more worrisome features or high‐risk stigmata during follow‐up. We created a multivariable prediction model using Cox‐proportional logistic regression analysis and performed an internal‐external validation.Results875 patients were included. After a mean follow‐up of 50 months (range 12‐157), 116 (13%) patients developed worrisome features or high‐risk stigmata. The final model included cyst size (HR 1.12, 95% CI 1.09‐1.15), cyst multifocality (HR 1.49, 95% CI 1.01‐2.18), ever having smoked (HR 1.40, 95% CI 0.95‐2.04), history of acute pancreatitis (HR 2.07, 95% CI 1.21‐3.55), and history of extrapancreatic malignancy (HR 1.34, 95% CI 0.91‐1.97). After validation, the model had good discriminative ability (C‐statistic 0.72 in the Mayo cohort, 0.71 in the Columbia cohort, 0.64 in the Erasmus cohort).ConclusionIn presumed side branch IPMNs without worrisome features or high‐risk stigmata at baseline, the Dutch‐American Risk stratification Tool (DART‐1) successfully identifies pancreatic lesions at low risk of developing worrisome features or high‐risk stigmata.
Deep Learning to Classify Intraductal Papillary Mucinous Neoplasms Using Magnetic Resonance Imaging
Hussein, Sarfaraz , Kandel, Pujan , Bolan, Candice W. , Bağcı, Ulaş , Wallace, Michael B. , Wallace, Michael B , Bagci, Ulas , Corral, Juan E.

Pancreas | June 7, 2019 | Volume: 48 | Issue: 6 | Pages: 805-810

10.1097/mpa.0000000000001327 Get It

Objective This study aimed to evaluate a deep learning protocol to identify neoplasia in intraductal papillary mucinous neoplasia (IPMN) in comparison to current radiographic criteria. Methods A computer-aided framework was designed using convolutional neural networks to classify IPMN. The protocol was applied to magnetic resonance images of the pancreas. Features of IPMN were classified according to American Gastroenterology Association guidelines, Fukuoka guidelines, and the new deep learning protocol. Sensitivity and specificity were calculated using surgically resected cystic lesions or healthy controls. Results Of 139 cases, 58 (42%) were male; mean (standard deviation) age was 65.3 (11.9) years. Twenty-two percent had normal pancreas; 34%, low-grade dysplasia; 14%, high-grade dysplasia; and 29%, adenocarcinoma. The deep learning protocol sensitivity and specificity to detect dysplasia were 92% and 52%, respectively. Sensitivity and specificity to identify high-grade dysplasia or cancer were 75% and 78%, respectively. Diagnostic performance was similar to radiologic criteria. Areas under the receiver operating curves (95% confidence interval) were 0.76 (0.70–0.84) for American Gastroenterology Association, 0.77 (0.70–0.85) for Fukuoka, and 0.78 (0.71–0.85) for the deep learning protocol ( P = 0.90). Conclusions The deep learning protocol showed accuracy comparable to current radiographic criteria. Computer-aided frameworks could be implemented as aids for radiologists to identify high-risk IPMN.
Enhanced family history screening is crucial to individualized cancer surveillance.
Macklin, Sarah , Wallace, Michael B. , Wallace, Michael B , Clift, Kristin , Presutti, R. John

Journal of Clinical Oncology | May 27, 2019 | Volume: 37 | Issue: 15_suppl | Pages: e13161-e13161

10.1200/jco.2019.37.15_suppl.e13161 Get It

e13161 Background: Capturing family health history is a simple and cost-effective way to identify individuals at increased risk for hereditary cancers. Several barriers exist to family history collection in the clinical setting. Self-reported histories can be limited, inaccurate or static. Physicians are often overwhelmed with data and “alert fatigue.” These complex factors make it difficult to quantify hereditary risks. Patients with increased genetic predisposition may be missed and may not receive individualized cancer surveillance measures. Methods: A practice improvement project was implemented at Mayo Clinic Florida to enhance family history screening. A questionnaire and simple scoring algorithm were developed to prompt referral for genetic counseling. This tool was pilot tested in a multi-specialty gastroenterology clinic. The questionnaire was administered in the waiting room (tablet interface). Patients with significant risk factors identified were contacted and offered genetic counseling. Results: Currently, 291 patients have completed the questionnaire. Thirty of the 60 patients identified to have significant familial risk factors met with a genetic counselor. Of the twenty who completed genetic testing, 9 patients received one or more variants of unknown significance. Two pathogenic variants were identified. One patient was molecularly confirmed to have multiple endocrine neoplasia type 2, which can allow for cascade screening in her unaffected sibling. A pathogenic ATM variant was found in a patient with a recent personal history of pancreatic cancer. The result prompted consideration of platinum based chemotherapy and/or PARP inhibitors in her cancer management. She has had a visible response thus far with the treatment. Her sister implemented a new surveillance regimen after testing positive for the familial variant. Conclusions: Enhanced family history screening is a low cost, effective method for the identification of patients who may benefit from hereditary cancer screening and genetic testing. Increased attention to family history is a vital component of precision medicine in any care setting.
Volumetric laser endomicroscopy and its application to Barrett's esophagus: results from a 1,000 patient registry
Smith, Michael S. , Konda, Vani J. , Gordon, Stuart R. , DeMeester, Steven R. , Joshi, Vivek , Ganguly, Eric K. , Mashimo, Hiroshi , Jobe, Blair A. , McKinley, Matthew , Wallace, Michael B. , Thakkar, Shyam , Schnoll‐Sussman, Felice , Sharaiha, Reem Z. , Tarnasky, P, Wolfsen, Herbert C. , Hawes, Robert H. , Lipham, John C. , Khara, Harshit S. , Navaneethan, U, Kedia, Prashant , Hasan, Muhammad K. , Sethi, Amrita , Samarasena, Jason , Siddiqui, Uzma D. , Gress, Frank G., Rodríguez, Reynaldo , Lee, C, Gonda, Tamas A. , Waxman, Irving , Hyder, S., Poneros, John M., Sharzehi, Kaveh , Palma, Jack A. Di, Sejpal, Divyesh V., Hagen, J. A., Rothstein, Richard, Sawhney, Mandeep , Malik, Zubair , Chang, Kenneth J. , Fichera, Alessandro , Gaidhane, Monica , Wallace, Michael B , Cash, Brooks D. , Trindade, Arvind J. , Diehl, David L. , Singh, Satish K. , Komatsu, Y, Kahaleh, Michel , Pleskow, Douglas K. , Hyder, S, Oh, Daniel S. , Berzin, Tyler M.

Diseases of the Esophagus | April 30, 2019 | Volume: 32 | Issue: 9 | Pages: No page available

10.1093/dote/doz029 Get It

SUMMARY Volumetric laser endomicroscopy (VLE) uses optical coherence tomography (OCT) for real-time, microscopic cross-sectional imaging. A US-based multi-center registry was constructed to prospectively collect data on patients undergoing upper endoscopy during which a VLE scan was performed. The objective of this registry was to determine usage patterns of VLE in clinical practice and to estimate quantitative and qualitative performance metrics as they are applied to Barrett's esophagus (BE) management. All procedures utilized the NvisionVLE Imaging System (NinePoint Medical, Bedford, MA) which was used by investigators to identify the tissue types present, along with focal areas of concern. Following the VLE procedure, investigators were asked to answer six key questions regarding how VLE impacted each case. Statistical analyses including neoplasia diagnostic yield improvement using VLE was performed. One thousand patients were enrolled across 18 US trial sites from August 2014 through April 2016. In patients with previously diagnosed or suspected BE (894/1000), investigators used VLE and identified areas of concern not seen on white light endoscopy (WLE) in 59% of the procedures. VLE imaging also guided tissue acquisition and treatment in 71% and 54% of procedures, respectively. VLE as an adjunct modality improved the neoplasia diagnostic yield by 55% beyond the standard of care practice. In patients with no prior history of therapy, and without visual findings from other technologies, VLE-guided tissue acquisition increased neoplasia detection over random biopsies by 700%. Registry investigators reported that VLE improved the BE management process when used as an adjunct tissue acquisition and treatment guidance tool. The ability of VLE to image large segments of the esophagus with microscopic cross-sectional detail may provide additional benefits including higher yield biopsies and more efficient tissue acquisition. Clinicaltrials.gov NCT02215291
Cost-effectiveness of Pancreatic Cancer Surveillance in High-Risk Individuals
Das, Ananya , Bruno, Marco J. , Wallace, Michael B. , Wallace, Michael B , Corral, Juan E.

Pancreas | April 5, 2019 | Volume: 48 | Issue: 4 | Pages: 526-536

10.1097/mpa.0000000000001268 Get It

Objective The aim of the study was to perform an economic analysis to identify the clinical and cost determinants of pancreatic cancer (PC) surveillance in high-risk individuals (HRIs). Methods A Markov model was created to compare the following 3 strategies: no screening, endoscopic ultrasound (EUS), and magnetic resonance imaging (MRI) screening. Patients were considered HRIs according to the Cancer of the Pancreas Screening consortium recommendations. Risk for developing PC, survival, and costs data were obtained from the Surveillance, Epidemiology, and End Results and Medicare databases. Surveillance effectiveness was obtained from a recent meta-analysis. Results Analysis of a cohort with fivefold relative risk of PC higher than the US population showed that MRI is the most cost-effective strategy. For those with the highest risk (>×20 relative risk), EUS became the dominant strategy. Our model was impacted by cost and imaging performance, but still cost-effective within the range reported in literature. Threshold analysis showed that if MRI increases greater than US $1600, EUS becomes more cost-effective. Once patients reached the age of 76 years, “no screening” was favored. Both surveillance strategies were cost-effective over a wide range of willingness to pay. Conclusions Abdominal imaging followed by pancreatectomy is cost-effective to prevent PC in HRIs, favoring MRI in moderate risk cases but EUS in those with highest risk.
Endoscopic scar assessment after colorectal endoscopic mucosal resection scars: when is biopsy necessary (EMR Scar Assessment Project for Endoscope (ESCAPE) trial)
Kandel, Pujan , Brand, Eelco C. , Pelt, Joe , Ball, Colleen T. , Chen, Wei‐Chung , Bouras, Ernest P., Gómez, Victoria , Woodward, Timothy A., Wallace, Michael B. , Raimondo, Massimo , Wallace, Michael B

Gut | January 11, 2019 | Volume: 68 | Issue: 9 | Pages: 1633-1641

10.1136/gutjnl-2018-316574 Get It

Objective It is unclear whether endoscopic assessment of scars after colorectal endoscopic mucosal resection (EMR) has to include biopsies, even if endoscopy is negative. Vice versa, endoscopic diagnosis of recurrent adenoma may not require biopsy before endoscopic reinterventions. We prospectively analysed various endoscopic modalities in the diagnosis of recurrence following EMR. Design We conducted a prospective study of patients undergoing colonoscopy after EMR of large (≥20 mm) colorectal neoplasia. Endoscopists predicted recurrence and confidence level with four imaging modes: high-definition white light (WL) and narrow-band imaging (NBI) with and without near focus (NF). Separately, 26 experienced endoscopists assessed offline images. Results Two hundred and thirty patients with 255 EMR scars were included. The prevalence of recurrent adenoma was 24%. Diagnostic values were high for all modes (negative predictive value (NPV) ≥97%, positive predictive value (PPV) ≥81%, sensitivity ≥90%, specificity ≥93% and accuracy ≥93%). In high-confidence cases, NBI with NF had NPV of 100% (95% CI 98% to 100%) and sensitivity of 100% (95% CI 93% to 100%). Use of clips at initial EMR increased diagnostic inaccuracy (adjusted OR=1.68(95% CI 1.01 to 2.75)). In offline assessment, specificity was high for all imaging modes (mean: ≥93% (range: 55%–100%)), while sensitivity was significantly higher for NBI-NF (82%(72%–93%)%)) compared with WL (69%(38%–86%); p<0.001), WL-NF (68%(55%–83%); p<0.001) and NBI (71%(59%–90%); p<0.001). Conclusion Our study demonstrates very high sensitivity and accuracy for all four imaging modalities, especially NBI with NF, for diagnosis of recurrent neoplasia after EMR. Our data strongly suggest that in cases of high confidence negative optical diagnosis based on NBI-NF, no biopsy is needed to confirm absence of recurrence during colorectal EMR follow-up. A high confidence positive optical diagnosis can lead to immediate resection of any suspicious area. In all cases of low confidence, biopsy is still required. Trial registration number NCT02668198 .
Survival of Patients with Oligometastatic Pancreatic Ductal Adenocarcinoma Treated with Combined Modality Treatment Including Surgical Resection: A Pilot Study
Kandel, Pujan , Wallace, Michael B. , Bolan, Candice W. , Woodward, Timothy A., Gómez, Victoria , Ritter, Ashton, Asbun, Horacio J. , Mody, Kabir , Bolan, Candice, Raimondo, Massimo , Ritter, Ashton W, Asbun, Horacio, Wallace, Michael B , Stauffer, John

Journal of Pancreatic Cancer | November 15, 2018 | Volume: 4 | Issue: 1 | Pages: 88-94

10.1089/pancan.2018.0011 Get It

Survival of patients with oligometastatic pancreatic ductal adenomacarcinoma treated with combined modality treatment including surgical resection: A pilot study.
Kandel, Pujan , Mody, Kabir , Asbun, Horacio J. , Bolan, Candice W. , Bridges, Mellena D., Woodward, Timothy A., Gómez, Victoria , Wallace, Michael B. , Wallace, Michael B , Stauffer, John , Raimondo, Massimo

Journal of Clinical Oncology | September 6, 2018 | Volume: 34 | Issue: 15_suppl | Pages: e15690-e15690

10.1200/jco.2016.34.15_suppl.e15690 Get It

Evaluation of genotoxicity related to oral methylene blue chromoendoscopy
Repici, Alessandro , Ciscato, Camilla , Wallace, Michael B. , Anderloni, Andrea , Carrara, Silvia , Leo, Milena Di , Hassan, Cesare , Hassan, Cesare , Wallace, Michael B , Sharma, Prateek

Endoscopy | August 29, 2018 | Volume: 50 | Issue: 10 | Pages: 1027-1032

10.1055/a-0630-1004 Get It

Abstract Background An oral formulation of methylene blue with colonic delivery (MB-MMX) has been developed to increase detection of colorectal polys during colonoscopy. Traditionally, there have been safety concerns regarding DNA damage when methylene blue is exposed to white light. The aim of this study was to evaluate DNA damage in colonic mucosa after MB-MMX chromoendoscopy. Methods This was an open-label phase II safety study to assess for genotoxicity on colorectal biopsies of patients undergoing two sequential colonoscopies before and after an oral dose of 200 mg MB-MMX added to their bowel prep. Analysis of a biomarker of double-stranded DNA breaks, γH2AX, was performed on biopsy specimens. Results Ten patients were included in the study. The mean expression of γH2AX ± 95 % confidence intervals of the 50 biopsies before and after MB-MMX administration were 0.58 ± 0.08 and 0.62 ± 0.09, respectively (P = 0.24). None of the analyzed samples showed excess positive γH2AX expression, confirming the absence of DNA damage on biopsies after methylene blue exposure. No deaths or serious adverse events occurred. Conclusions An oral dose of 200 mg of MB-MMX did not result in any detectable DNA damage.
Correction: Learning curve and competence for volumetric laser endomicroscopy in Barrett’s esophagus using cumulative sum analysis
Inamdar, Sumant , Smith, Michael S. , Rosen, Lisa, Han, Dennis , Chang, Kenneth J. , Leggett, Cadman, Lightdale, Charles J. , Sejpal, Divyesh V., Tearney, Guillermo J. , Thomas, Rebecca, Wallace, Michael B. , Leggett, Cadman L. , Wallace, Michael B , Leggett, Cadman L , Trindade, Arvind J. , Pleskow, Douglas K.

Endoscopy | July 27, 2018 | Volume: 50 | Issue: 05 | Pages: C10-C10

10.1055/a-0658-2867 Get It