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Buttar, Navtej S

Mayo Clinic

Mayo Clinic, Division of Gastroenterology and Hepatology, 200 2nd Street SW, Rochester, MN 55905, USA.

Citations 11

Patient Characteristics and Outcomes of Endoscopically Placed Dedicated Transgastric Jejunal Tubes Compared to Percutaneous Endoscopic Gastrostomy With Jejunal Extension Tubes
Kek, Laura , Bruining, David H. , Buttar, Navtej , Harmsen, William S. , Song, Louis M. Wong Kee , Kek, Laura D , Buttar, Navtej S, Abou Zeid, Hadi, Wong Kee Song, Louis M, Zeid, Hadi Khaled Abou , Storm, Andrew C. , Coelho–Prabhu, Nayantara

DEN Open | September 26, 2025 | Volume: 6 | Issue: 1 | Pages: No page available

10.1002/deo2.70213 Get It

ABSTRACT Objectives Patients requiring long‐term enteral nutrition or continuous infusion of carbidopa/levodopa can benefit from jejunostomy tube placement. Recently, directly placed percutaneous transgastric jejunal tubes (TGJs) have been used instead of gastrostomy tubes with jejunal extensions (PEG‐Js) for enteral access. We aim to compare patient characteristics and outcomes after placement of TGJs placed via the introducer technique compared to PEG‐Js. Methods We performed a retrospective study of 141 patients (TGJ = 58, PEG‐J = 83) assessed at Mayo Clinic between 2010 and 2024. Patients were identified using a prospectively maintained procedure data registry. Demographic data, patient characteristics, procedural indications, complications, and first‐replacement date were gathered. Statistical analysis included the Wilcoxon rank sum test, chi‐square test, Fisher's exact test, and Kaplan‐Meier estimates. Patients receiving carbidopa/levodopa were excluded from complications analysis due to the carbidopa/levodopa tube's proprietary structure. A p ‐value of <0.05 was set as a threshold for significance. Results Our results demonstrated no difference in cumulative incidence of complications within 1 year for TGJs and PEG‐Js, p ‐value 0.48. Regarding time to first replacement, treating death as a competing risk factor, there was no statistically significant difference in cumulative incidence of replacement within 1 year for TGJs and PEG‐Js, p ‐value 0.389. Conclusions Our study demonstrates that both direct TGJs and PEG‐Js are safe options for long‐term jejunal feeding. More studies are needed to compare endoscopic to radiologically placed percutaneous transgastric jejunal feeding tubes.
Plicating the Gut: Endoscopic Suturing to Resolve Ileal Intussusception Causing Ileocolic Anastomotic Obstruction
Chopra, Preeyati , Ohri, Ashwariya , Buttar, Navtej , Ohri, Ashwariya , Buttar, Navtej S, Goyal, Mayank

ACG Case Reports Journal | May 1, 2025 | Volume: 12 | Issue: 5 | Pages: e01662

10.14309/crj.0000000000001662 Get It

Inhibition of the BMP pathway prevents development of Barrett’s-associated adenocarcinoma in a surgical rat model
Westra, Wytske, Straub, Daniëlle, Buttar, Navtej , Wang, Kenneth K, Krishnadath, Kausilia K. , Westra, Wytske M, Buttar, Navtej S, Milano, Francesca

Diseases of the Esophagus | October 31, 2021 | Volume: 35 | Issue: 5 | Pages: No page available

10.1093/dote/doab072 Get It

Summary Introduction Esophageal adenocarcinoma (EAC) is an aggressive cancer, associated with reflux esophagitis and intestinal metaplasia (IM). One underlying biological mechanism, which possibly drives the development of EAC, is the dysregulated expression of Bone Morphogenetic Proteins (BMPs). Aim To investigate if local delivery of Noggin, a BMP antagonist, reduced EAC. Methods After obtaining proof of principal on local delivery of a Noggin/Sucralfate substance, a randomized controlled trial to test the effects of Noggin on EAC development was performed in a surgical rat model. In the model, an esophago-jejunostomy leads to development of reflux-esophagitis, IM and eventually EAC. Rats were treated by Noggin/Sucralfate or Sucralfate alone. Treatment was administered from 26 to 29 weeks after the operation. Results Of the 112 operated rats, 52 survived beyond 26 weeks. Finally, 25 rats treated with Noggin/Sucralfate and 21 with Sucralfate, were evaluated. At the end, 39 (85%) of the animals had IM while 28 (61%) developed cancer. There were significantly more cancers in the Noggin/Sucralfate arm (50%) versus the Sucralfate group (73%) (Chi square, P &lt; 0.05). Most cancers were mucous producing T3 adenocarcinomas. There were no significant differences in the amount of IM, size or grade of the cancers, or expression of columnar and squamous markers between the two groups. Conclusion In this study, we demonstrated that inhibition of BMPs by Noggin reduced development of EAC in a surgical esophagitis-IM-EAC rat model. In future, effective targeting of the BMP pathway with selective BMP-inhibitors could become an important asset to improve EAC patient outcome.
Randomized Phase II Trial of Polyphenon E versus Placebo in Patients at High Risk of Recurrent Colonic Neoplasia
Sinicrope, Frank A. , Viggiano, Thomas R., Buttar, Navtej , Song, Louis M. Wong Kee , Schroeder, Kenneth W., Kraichely, Robert E., Larson, Mark V., Kisiel, John B. , Gostout, Christopher J., Kalaiger, Abdul M., Patai, Árpád V. , Della’Zanna, Gary , Meyers, Jeffrey P., Foster, Nathan R. , Yang, Chung S. , Sontag, Stephen J. , Buttar, Navtej S, Sedlack, Robert E. , Kisiel, John B , Patai, Árpád V , Della'Zanna, Gary , Umar, Asad , Limburg, Paul J. , Yang, Chung S , Sontag, Stephen , Sinicrope, Frank A , Kalaiger, Abdul Mukhtadir

Cancer Prevention Research | March 1, 2021 | Volume: 14 | Issue: 5 | Pages: 573-580

10.1158/1940-6207.capr-20-0598 Get It

Abstract Polyphenon E (Poly E) is a green tea polyphenol preparation whose most active component is epigallocatechin gallate (EGCG). We studied the cancer preventive efficacy and safety of Poly E in subjects with rectal aberrant crypt foci (ACF), which represent putative precursors of colorectal cancers. Eligible subjects had prior colorectal advanced adenomas or cancers, and had ≥5 rectal ACF at a preregistration chromoendoscopy. Subjects (N = 39) were randomized to 6 months of oral Poly E (780 mg EGCG) daily or placebo. Baseline characteristics were similar by treatment arm (all P &gt;0.41); 32 of 39 (82%) subjects completed 6 months of treatment. The primary endpoint was percent reduction in rectal ACF at chromoendoscopy comparing before and after treatment. Among 32 subjects (15 Poly E, 17 placebo), percent change in rectal ACF number (baseline vs. 6 months) did not differ significantly between study arms (3.7% difference of means; P = 0.28); total ACF burden was also similar (−2.3% difference of means; P = 0.83). Adenoma recurrence rates at 6 months were similar by arm (P &gt; 0.35). Total drug received did not differ significantly by study arm; 31 (79%) subjects received ≥70% of prescribed Poly E. Poly E was well tolerated and adverse events (AE) did not differ significantly by arm. One subject on placebo had two grade 3 AEs; one subject had grade 2 hepatic transaminase elevations attributed to treatment. In conclusion, Poly E for 6 months did not significantly reduce rectal ACF number relative to placebo. Poly E was well tolerated and without significant toxicity at the dose studied. Prevention Relevance: We report a chemoprevention trial of polyphenon E in subjects at high risk of colorectal cancer. The results show that polyphenon E was well tolerated, but did not significantly reduce the number of rectal aberrant crypt foci, a surrogate endpoint biomarker of colorectal cancer.
Efficacy and safety of combined endoscopic cyanoacrylate injection and balloon-occluded retrograde transvenous occlusion (BRTOcc) of gastrorenal shunts in patients with bleeding gastric fundal varices
Bazerbachi, Fateh , Dobashi, Akira , Kumar, Swarup , Misra, Sanjay , Buttar, Navtej , Song, Louis M. Wong Kee , Buttar, Navtej S, Wong Kee Song, Louis M, Misra, Sanjay , Bazerbachi, F

Gastroenterology Report | October 22, 2020 | Volume: 9 | Issue: 3 | Pages: 212-218

10.1093/gastro/goaa082 Get It

Abstract Background Endoscopic cyanoacrylate (glue) injection of fundal varices may result in life-threatening embolic adverse events through spontaneous gastrorenal shunts (GRSs). Balloon-occluded retrograde transvenous occlusion (BRTOcc) of GRSs during cyanoacrylate injection may prevent serious systemic glue embolization through the shunt. This study aimed to evaluate the efficacy and safety of a combined endoscopic–interventional radiologic (BRTOcc) approach for the treatment of bleeding fundal varices. Methods We retrospectively analysed the data of patients who underwent the combined procedure for acutely bleeding fundal varices between January 2010 and April 2018. Data were extracted for patient demographics, clinical and endoscopic findings, technical details, and adverse events of the endoscopic–BRTOcc approach and patient outcomes. Results We identified 30 patients (13 [43.3%] women; median age 58 [range, 25–92] years) with gastroesophageal varices type 2 (53.3%, 16/30) and isolated gastric varices type 1 (46.7%, 14/30) per Sarin classification, and median clinical and endoscopic follow-up of 151 (range, 4–2,513) days and 98 (range, 3–2,373) days, respectively. The median volume of octyl-cyanoacrylate: Lipiodol injected was 7 (range, 4–22) mL. Procedure-related adverse events occurred in three (10.0%) patients, including transient fever, non-life-threatening pulmonary glue embolism, and an injection-site ulcer bleed. Complete gastric variceal obturation was achieved in 18 of 21 patients (85.7%) at endoscopic follow-up. Delayed variceal rebleeding was confirmed in one patient (3.3%) and suspected in two patients (6.7%). Although no procedure-related deaths occurred, the overall mortality rate was 46.7%, primarily from liver-disease progression and co-morbidities. Conclusion The combined endoscopic–BRTOcc procedure is a relatively safe and effective technique for bleeding fundal varices, with a high rate of variceal obturation and a low rate of serious adverse events.
Discovery, Validation, and Application of Novel Methylated DNA Markers for Detection of Esophageal Cancer in Plasma
Qin, Yi , Wu, Chung Wah, Sawas, Tarek , Burger, Kelli N. , Yab, Tracy C. , Lidgard, Graham P. , Allawi, Hatim T. , Buttar, Navtej , Smyrk, Thomas C. , Iyer, Prasad G. , Katzka, David A. , Ahlquist, David A. , Wu, Chung W, Mahoney, Douglas W. , Buttar, Navtej S, Kisiel, John B , Qin, Y , Taylor, William R. , Sun, Zhifu , Kisiel, John B.

Clinical Cancer Research | September 16, 2019 | Volume: 25 | Issue: 24 | Pages: 7396-7404

10.1158/1078-0432.ccr-19-0740 Get It

Abstract Purpose: The burden of esophageal cancer continues to rise, and noninvasive screening tools are needed. Methylated DNA markers (MDM) assayed from plasma show promise in detection of other cancers. For esophageal cancer detection, we aimed to discover and validate MDMs in tissue, and determine their feasibility when assayed from plasma. Experimental Design: Whole-methylome sequencing was performed on DNA extracted from 37 tissues (28 EC; 9 normal esophagus) and 8 buffy coat samples. Top MDMs were validated by methylation specific PCR on tissue from 76 EC (41 adeno, 35 squamous cell) and 17 normal esophagus. Quantitative allele-specific real-time target and signal amplification was used to assay MDMs in plasma from 183 patients (85 EC, 98 controls). Recursive partitioning (rPART) identified MDM combinations predictive of esophageal cancer. Validation was performed in silico by bootstrapping. Results: From discovery, 23 candidate MDMs were selected for independent tissue validation; median area under the receiver operating curve (AUC) for individual MDMs was 0.93. Among 12 MDMs advanced to plasma testing, rPART modeling selected a 5 MDM panel (FER1L4, ZNF671, ST8SIA1, TBX15, ARHGEF4) which achieved an AUC of 0.93 (95% CI, 0.89–0.96) on best-fit and 0.81 (95% CI, 0.75–0.88) on cross-validation. At 91% specificity, the panel detected 74% of esophageal cancer overall, and 43%, 64%, 77%, and 92% of stages I, II, III, and IV, respectively. Discrimination was not affected by age, sex, smoking, or body mass index. Conclusions: Novel MDMs assayed from plasma detect esophageal cancer with moderate accuracy. Further optimization and clinical testing are warranted.
Efficacy of Difluoromethylornithine and Aspirin for Treatment of Adenomas and Aberrant Crypt Foci in Patients with Prior Advanced Colorectal Neoplasms
Velamala, Pruthvi, Song, Louis M. Wong Kee , Viggiano, Thomas R., Bruining, David H. , Rajan, Elizabeth , Gostout, Christopher J., Kraichely, Robert E., Buttar, Navtej , Schroeder, Kenneth W., Larson, Mark V., Sweetser, Seth , Sedlack, Robert, Sinicrope, Stephen N. , Della’Zanna, Gary , Noaeill, Joni S., Meyers, Jeffrey P., Foster, Nathan R. , Velamala, Pruthvi R, Buttar, Navtej S, Kisiel, John B , Sweetser, Seth R, Sedlack, Robert R, Richmond, Ellen S. , Umar, Asad, Della'Zanna, Gary, Sinicrope, Stephen N , Sinicrope, Frank A. , Kisiel, John B. , Umar, Asad

Cancer Prevention Research | September 4, 2019 | Volume: 12 | Issue: 11 | Pages: 821-830

10.1158/1940-6207.capr-19-0167 Get It

Abstract Difluoromethylornithine (DFMO), an inhibitor of polyamine synthesis, was shown to act synergistically with a NSAID for chemoprevention of colorectal neoplasia. We determined the efficacy and safety of DFMO plus aspirin for prevention of colorectal adenomas and regression of rectal aberrant crypt foci (ACF) in patients with prior advanced adenomas or cancer. A double-blinded, placebo-controlled trial was performed in 104 subjects (age 46–83) randomized (1:1) to receive daily DFMO (500 mg orally) plus aspirin (325 mg) or matched placebos for one year. All polyps were removed at baseline. Adenoma number (primary endpoint) and rectal ACF (index cluster and total) were evaluated at a one year colonoscopy. ACF were identified by chromoendoscopy. Toxicity was monitored, including audiometry. Eighty-seven subjects were evaluable for adenomas or ACF modulation (n = 62). At one year of treatment, adenomas were detected in 16 (38.1%) subjects in the DFMO plus aspirin arm (n = 42) versus 18 (40.9%) in the placebo arm (n = 44; P = 0.790); advanced adenomas were similar (n = 3/arm). DFMO plus aspirin was associated with a statistically significant reduction in the median number of rectal ACF compared with placebo (P = 0.036). Total rectal ACF burden was also reduced in the treatment versus the placebo arm relative to baseline (74% vs. 45%, P = 0.020). No increase in adverse events, including ototoxicity, was observed in the treatment versus placebo arms. While adenoma recurrence was not significantly reduced by one year of DFMO plus aspirin, the drug combination significantly reduced rectal ACF number consistent with a chemopreventive effect.
Esophageal overtubes provide no benefit to safety or technical success in upper gastrointestinal tract endoscopic suturing
Storm, Andrew C. , Matar, Reem , Song, Louis M. Wong Kee , Sawas, Tarek , Buttar, Navtej , Topazian, Mark , Wong Kee Song, Louis M, Bazerbachi, Fateh , Buttar, Navtej S, Abu Dayyeh, Barham K, Matar, Reem , Storm, Andrew C , Vargas, Eric J. , Dayyeh, Barham K. Abu

Endoscopy International Open | July 11, 2019 | Volume: 07 | Issue: 07 | Pages: E919-E921

10.1055/a-0953-2152 Get It

Abstract Background and study aim The role of esophageal overtubes in upper gastrointestinal endoscopic suturing is unknown. This study aimed to determine whether overtube use was associated with technical success or adverse events. Patients and methods A retrospective review of consecutive patients who underwent endoscopic suturing for various indications was performed. Results A total of 719 patients underwent endoscopic suturing for various indications, including endoscopic bariatric procedures in 262, stent fixation in 258, defect closure in 190, and hemostasis in nine. An overtube was used in 186 procedures (25.9 %). Technical success was achieved in all cases. Minor mucosal trauma occurred in 15 cases (8.1 %) with use of an overtube, and none without an overtube (P < 0.0001). No full-thickness esophageal perforation or hemorrhage related to overtube use or the suturing device occurred. Conclusions Endoscopic suturing can be performed safely for a variety of indications, including endoscopic bariatric procedures, defect repair, and stent fixation without an esophageal overtube. Minor esophageal mucosal trauma and equipment cost are increased when an overtube is used.
Safety and efficacy of coaxial lumen-apposing metal stents in the management of refractory gastrointestinal luminal strictures: a multicenter study
Heffley, Jason D. , Dayyeh, Barham Abu, Nieto, José , Sawas, Tarek , Zaghlol, Raja , Buttar, Navtej , Topazian, Mark , Song, Louis Wong Kee, Levy, Michael J. , Keilin, Steve, Cai, Qiang , Bazerbachi, Fateh , Abu Dayyeh, Barham K, Vargas, Eric J. , Buttar, Navtej S, Wong Kee Song, Louis M, Levy, Michael J. , Willingham, Field F.

Endoscopy International Open | September 12, 2017 | Volume: 05 | Issue: 09 | Pages: E861-E867

10.1055/s-0043-114665 Get It

Abstract Background and aims Benign gastrointestinal (GI) strictures are often refractory to standard endoscopic interventions. Fully covered coaxial lumen-apposing metal stents (LAMS) have emerged as a novel therapy for these strictures. The aim of this study was to evaluate the safety and efficacy of LAMS for refractory GI strictures. Patients and methods A retrospective analysis was performed for patients who underwent LAMS placement for benign luminal strictures in three US centers between January 2014 and December 2016. The primary outcomes were technical success and initial clinical success of LAMS placement. Secondary outcomes were stent migration, rate of re-intervention, and adverse events. Results A total of 49 patients underwent 56 LAMS placement procedures. Previous treatment had failed in 39 patients (79.6 %), and anastomotic strictures were the indication in 77.6 % (38/49), with the most common site being gastrojejunal (34.7 % [17/49]). Technical success was achieved in all procedures and initial clinical success was achieved in 96.4 % of all procedures (54/56). Patient initial clinical success was 95.9 % (47/49). Stent migration occurred in 17.9 % of procedures, and was more likely to occur at sites in the lower GI tract (P = 0.02). The mean stent dwell time was 100.6 days, and the mean follow-up was 169.8 days. Minor adverse events, not requiring hospitalization, occurred in 33.9 % of procedures, including subsequent stricture progression (10.7 %). In cases where LAMS were removed, mean follow-up time was 102.2 days. The re-intervention rate was 75 % at 300 days follow-up after stent removal. Of the LAMS placed at anastomotic strictures, 36.4 % required re-intervention, with approximately two-thirds of these re-interventions requiring placement of a new stent or surgery. Conclusion LAMS placement was successful for the management of refractory GI strictures, with good technical and initial clinical success rates. However, re-intervention rates after LAMS removal were high, and many strictures were not resolved by an extended period of stenting with these coaxial stents. LAMS placement offers additional therapeutic options and in selected cases might be considered a destination therapy for patients with recalcitrant benign strictures.
Lumen-apposing covered self-expanding metal stent for management of benign gastrointestinal strictures
Buttar, Navtej , Gostout, Christopher J., Levy, Michael J. , Martin, John A. , Petersen, Bret T. , Topazian, Mark , Song, Louis Wong Kee, Dayyeh, Barham Abu, Buttar, Navtej S, Gostout, Christopher, Martin, John, Petersen, Bret, Wong Kee Song, Louis M, Abu Dayyeh, Barham K, Majumder, Shounak , Levy, Michael J.

Endoscopy International Open | December 16, 2015 | Volume: 04 | Issue: 01 | Pages: E96-E101

10.1055/s-0041-108195 Get It