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Han, Samuel

https://orcid.org/0000-0001-7373-7984

Mayo Clinic

Mayo Clinic

Citations 13

Comprehensive Assessment of Direct and Passive Smoking Across the Pancreatitis Spectrum
Yadav, Dhiraj, Xu, Jun, Fisher, W. E., Fogel, Evan L. , Forsmark, Chris, Hart, Phil A., Li, Liang, Sj, Pandol, Park, Walter G., Trikudanathan, Guru, Vege, Santhi Swaroop, Conwell, Darwin L., Park, Walter G. , Han, Samuel , Yadav, Dhiraj, Bellin, Melena D. , Fisher, William E., Forsmark, Chris E. , Trikudanathan, Guru , Van Den Eeden, Stephen K , Vege, Santhi Swaroop , Conwell, Darwin L. , Jeon, Christie Y.

Pancreas | January 16, 2026 | Volume: 55 | Issue: 6 | Pages: e653-e660

10.1097/mpa.0000000000002621 Get It

Objectives: Smoking is a key risk factor for pancreatitis, contributing to pathogenesis and disease progression. Data regarding second-hand smoking, or passive smoking (PS) exposure, are lacking. We therefore aimed to assess the impact of PS exposure across the pancreatitis spectrum. Methods: We analyzed baseline data from the PROCEED study, a multicenter study in the United States including patients with acute (AP), recurrent acute (RAP), and chronic (CP) pancreatitis. Participants detailed their individual smoking history and PS exposure, which was compared between AP, RAP, and CP subgroups. Participant factors and clinical characteristics were compared by level of individual and PS exposure. Results: Among 1369 participants (190 AP, 498 RAP, 681 CP), 346 (25.3%) were current and 409 (29.9%) were former smokers. The CP subgroup had the highest proportion of current smokers (36.7% CP vs 15.1% RAP, 11.1% AP, P < 0.001). PS exposure was also significantly higher in the CP subgroup (68.6% CP vs 58.2% RAP, 55.3% AP, P < 0.001). A minority (16.3%) with CP reported no smoking exposure (by self or passive) while nearly half smoked ≥20 pack-years. The mean PS duration was significantly higher in CP participants (21.8 y) compared with those with AP (17.8 y) or RAP (18.9 y) ( P < 0.0166). Conclusions: In this multicenter study, we affirmed an association with smoking use and intensity with CP-related complications. For the first time, we report a high prevalence of prior exposure to passive smoking in all pancreatitis subtypes, which requires further study to understand the impact on disease outcomes.
The Challenge of Pancreatic Duct Cannulation in Chronic Pancreatitis
Karaisz, Fred, Fogwe, Delvise T. , Nikahd, Melica , Papachristou, Georgios I. , Park, Erica , Han, Samuel

Pancreas | November 27, 2025 | Volume: 55 | Issue: 5 | Pages: e539-e540

10.1097/mpa.0000000000002598 Get It

Participant Retention in a Prospective Multicenter Cohort of Participants With Pancreatitis and Factors Associated With Attrition
Choate, Radmila , Xu, Jun , Easler, Jeffrey J. , Phillips, Anna E. , Fisher, William E., Fogel, Evan L. , Forsmark, Chris E. , Hart, Phil A. , Park, Walter G. , Vege, Santhi Swaroop, Conwell, Darwin L. , Yadav, Dhiraj, Choate, Radmila , Xu, Jun , Han, Samuel , Phillips, Anna E., Bellin, Melena D. , Pandol, Stephen J. , Serrano, Jose, Van Den Eeden, Stephen K , Vege, Santhi Swaroop , Li, Liang , Conwell, Darwin L. , Yadav, Dhiraj

Pancreas | October 13, 2025 | Volume: 55 | Issue: 2 | Pages: e162-e172

10.1097/mpa.0000000000002550 Get It

Objectives: Participant retention is essential in prospective studies to minimize bias and maintain validity. This study aimed to estimate retention rates and identify factors influencing attrition in a multicenter cohort (PROCEED) of US adults with acute/recurrent acute pancreatitis (AP/RAP) and chronic pancreatitis (CP). Methods: Participants from the PROCEED study with AP/RAP or CP eligible for follow-up within the designated visit window were included. Retention was defined as completing at least one follow-up visit during the observation period. Retention was analyzed by follow-up mode (in-person and/or medical record review) and disease type (AP/RAP and CP). Retention factors were assessed using univariate analyses (Wilcoxon rank-sum for continuous variables, χ 2 /Fisher's exact for categorical) and multivariable logistic regression. Missing data were adjusted using multiple imputations in statistical modeling. Results: Among 1279 participants (AP/RAP: n=632, median age 47, 48.9% female; CP: n=647, median age 54, 46.5% female), we observed high cumulative and annualized retention rates, with improved retention when incorporating medical record reviews. In multivariable regression analyses, older age was statistically significantly associated with in-person retention in the AP/RAP group ( P =0.0001), while a higher self-reported physical health (assessed with PROMIS Global Health Physical Health T-score) was a key predictor of retention in CP ( P =0.034). Conclusions: Integrating medical records review substantially enhanced retention rates, enabling robust analyses of pancreatitis outcomes and disease progression. Older age and better self-reported physical health were key predictors of retention, highlighting the need for targeted strategies to enhance engagement among younger participants and those with poorer health in long-term studies.
Multiple substance use and the risk of pancreatitis: a systematic review
Adeniran, Esther, Yadav, Dhiraj, Tan, Judy Y. , Lo, Simon K. , Adeniran, Esther A , Jiang, Yi, Han, Samuel , Pandol, Stephen J. , Jeon, Christie Y.

Therapeutic Advances in Gastroenterology | August 25, 2025 | Volume: 18 | Issue: No issue available | Pages: No page available

10.1177/17562848251365030 Get It

Background: The impact of multiple substance use on the risk of pancreatitis remains underexplored. Objective: To systematically review peer-reviewed observational studies assessing the association of multiple substance use with the risk of acute pancreatitis (AP) or chronic pancreatitis (CP) in adults. Design: We conducted a systematic review informed by the Preferred Reporting Items for Systematic Review and Meta-Analyses guideline. Data sources and methods: EMBASE, MEDLINE, and PsycINFO were searched up to March 2024. Reference lists of included studies were reviewed. From 5205 records identified, 181 relevant records were evaluated in full text. Studies evaluating the association of ⩾2 substances, including tobacco, alcohol, cannabis, and illicit substances, with AP or CP were included. Data were extracted by one reviewer, with quality control by a second reviewer. Quality assessments were independently conducted by two reviewers, with differences resolved by a third. Results: Of 11 included studies, 6 investigated AP as the outcome and 5 examined CP. Among AP studies, 5 comparing smoking and alcohol to alcohol-only use showed high heterogeneity ( I 2 = 90.9%), with relative risks (RRs) from 1.40 to 11.40. One study examining cannabis and alcohol versus alcohol found a lower risk of AP in cannabis users. Among CP studies, four comparing smoking and alcohol to alcohol-only use were heterogeneous ( I 2 = 81%) with odds ratios 1.21–31.50. Where examined, smoking increases the risk of AP and CP in a dose-dependent fashion. Heavy alcohol users demonstrated a significant increase in CP risk across all smoking categories in one study. Conclusion: Combined alcohol and tobacco use increases pancreatitis risk compared to single substance use, despite heterogeneity in RRs and exposure definitions. Evidence suggests a dose-dependent impact of smoking on pancreatitis risk when added to alcohol. Studies on the impact of a combination of other substance use on pancreatitis risk are needed. Trial registration (PROSPERO): CRD42024503677.
Prostaglandin E2 as a Mechanistic Biomarker of Chronic Pancreatitis
Saloman, Jami L. , Jefferson, Bahiyyah, Fisher, William E., Fogel, Evan L. , Hart, Phil A. , Park, Walter G. , Vege, Santhi Swaroop , Yadav, Dhiraj , Topazian, Mark , Conwell, Darwin L. , Saloman, Jami L , Han, Samuel , Li, Liang

Clinical and Translational Gastroenterology | August 4, 2025 | Volume: 16 | Issue: 10 | Pages: e00897

10.14309/ctg.0000000000000897 Get It

INTRODUCTION: Chronic pancreatitis (CP) is a disease associated with chronic inflammation, fibrosis, and pain. There is a lack of tools available that facilitate early diagnosis, when intervention could prevent irreversible damage. Pilot data suggested prostaglandin E2 (PGE2) as a candidate biomarker for early CP. PGE2 activates signaling pathways that promote inflammation, pain, and fibrosis. METHODS: We assessed PGE2, metabolites, and downstream targets in pancreatic fluid collected endoscopically 0–10 (n = 110) and 10–20 (n = 111) minutes after intravenous secretin administration. PGE2 and metabolites were measured in plasma (n = 75) and urine (n = 71) from the same subjects. Subjects were enrolled in the PROCEED study and classified symptomatic controls, acute/recurrent acute pancreatitis (AP/RAP), or CP. RESULTS: A significant main effect was detected in 10–20 minutes pancreas fluid ( P = 0.027) and plasma ( P = 0.046); post hoc testing showed PGE2 was lower in the AP/RAP group compared with symptomatic controls. There was also trend toward lower PGE2 in urine ( P = 0.062). To elucidate the active downstream pathways, calcitonin gene-related peptide, substance P, and matrix metalloproteinases (MMPs) 1, 2, 3, 7, 9, and 13 were measured in pancreas fluid. A significant difference between the 3 groups was detected for both MMP7 and MMP9. MMP7 was elevated in individuals with CP vs AP/RAP ( P = 0.012) for samples collected early but both time points for MMP9 ( P = 0.027, P = 0.002). DISCUSSION: While PGE2 is detectable in pancreas fluid, these data suggest that it may not be sensitive enough to distinguish between AP/RAP and CP. However, MMPs may distinguish between stages of pancreatitis and require further testing as potential diagnostic biomarkers.
Gastro-Entero-Colic Fistula After Successful EUS Guided Gastroenterostomy
Ladd, Antonio Mendoza , Ladna, Michel, Pecha, Luke, Sharzehi, Kaveh , Bhardwaj, Meera., Vargas, Jorge, Gutierrez, Olaya I. Brewer , Schlag, Christoph , Hindryckx, Pieter , Hucl, Tomáš , Sethi, Amrita , Masaryk, Viliam , Khara, Harshit S. , Mendoza Ladd, Antonio , Pérez‐Cuadrado‐Robles, Enrique , Han, Samuel , Vargas, Jorge, Inamdar, Sumant , Pham, Khanh Do-Cong

Journal of Clinical Gastroenterology | July 21, 2025 | Volume: 60 | Issue: 6 | Pages: 543-548

10.1097/mcg.0000000000002178 Get It

Background: EUS-guided gastroenterostomy (EUS-GE) is an effective option for the management of gastric outlet obstruction (GOO). Due to the poor prognosis of patients undergoing it, data on its long-term adverse events (AE) is scarce. Herein, we describe a cohort of patients with gastro-entero-colic fistula (GECF) as a late AE of previously successful EUS-GE. Methods: Patients who developed a GECF after EUS-GE from 10 high-volume centers were analyzed. Information collected included demographic characteristics, indications, clinical and technical success rates, stent type and size, fistula characteristics, management, and outcomes. Results: Sixteen cases were identified. The mean interval from index EUS-GE to the diagnosis of GECF was 4 to 8 weeks. The most common cause of GOO was pancreatic adenocarcinoma (PDAC). The transverse colon was the most common site for the GECF (14 patients). A 20×10 mm lumen apposing metal stent (LAMS) was utilized in 10 patients. Endoscopic management with a variety of modalities was successful in 13 cases. Follow-up interval after endoscopic management of the fistula averaged 2 to 4 weeks. At the time of the manuscript elaboration, 10 patients had died, 5 were alive, and 1 was lost to follow-up. Conclusions: This is the first description of a cohort of patients with GECF after EUS-GE. The exact mechanisms leading to GECF in these cases are unknown. Possible explanations include inadvertent colon puncture during the index procedure and/or entrapment of mesocolon. More data is needed to further characterize this AE.
Oral Indomethacin for Chronic Pancreatitis: Results From the PAIR Randomized Placebo-Controlled Trial
Vege, Santhi Swaroop , Hart, Phil A. , Saloman, Jami L. , Xu, Jun , Li, Liang , Cruz‐Monserrate, Zobeida , Palermo, Tonya M. , Yadav, Dhiraj , Topazian, Mark , Conwell, Darwin L. , Saloman, Jami L , Han, Samuel , Xu, Jun , Hill, Rachel, Hao, Wenrui

Clinical and Translational Gastroenterology | July 7, 2025 | Volume: 16 | Issue: 9 | Pages: e00888

10.14309/ctg.0000000000000888 Get It

INTRODUCTION: Chronic pancreatitis (CP) remains difficult to manage with few treatment options. Prior studies have implicated prostaglandin E 2 (PGE 2 ) in mediating chronic inflammation in the pancreas. Therefore, we aimed to evaluate whether indomethacin, a cyclooxygenase-2 enzyme inhibitor, would reduce PGE 2 levels in CP. METHODS: In this pilot multicenter randomized controlled trial, participants with CP received oral indomethacin (50 mg) or placebo twice daily for 28 days. Measurement of PGE 2 levels in pancreatic fluid collected endoscopically after secretin administration at baseline and posttreatment (day 28) was performed. Quality of life and pain were also assessed at baseline and posttreatment. RESULTS: A total of 27 participants were randomized (indomethacin = 13, placebo = 14). Although PGE 2 levels decreased after treatment in pancreas fluid, plasma, and saliva in the indomethacin group, there was no significant difference in mean change in pancreas fluid PGE 2 levels between the indomethacin and placebo groups (−457.7 pg/mL vs −840.4 pg/mL, P = 0.25). There was also no significant change in pain severity composite score (−1.3 indomethacin vs −0.5 placebo, P = 0.33), but the improvement in pain interference score (−2.9 indomethacin vs −0.4, P = 0.058) trended toward significance. There was no difference in adverse events between the 2 groups. DISCUSSION: In this phase 1/2 study, oral indomethacin was safe and well tolerated by patients with CP. Although there was no significant difference in change in PGE 2 levels, further studies are needed to determine the effect of indomethacin on the inflammatory pathway of CP and patient-centered outcomes.
The Success and Safety of Endoscopic Retrograde Cholangiopancreatography in Surgically Altered Gastrointestinal Anatomy
Han, Samuel , Edmundowicz, Steven A. , Attwell, Augustin , Hammad, Hazem, Wani, Sachin , Edmundowicz, Steven A , Kolb, Jennifer M. , Shah, Raj J.

Medical Sciences | February 11, 2025 | Volume: 13 | Issue: 1 | Pages: 18

10.3390/medsci13010018 Get It

Background/Objectives: Performing endoscopic retrograde cholangiopancreatography (ERCP) in surgically altered gastrointestinal anatomy remains challenging, frequently necessitating the use of forward-viewing endoscopes. Given the challenge in endoscope selection based on the type of altered anatomy, the aim of this study was to examine ERCP success rates by specific endoscopes for different anatomy types. Methods: This single-center retrospective study examined ERCPs performed in patients with surgically altered gastrointestinal anatomy during an 18-year period. Enteroscopy success, cannulation success, and intervention success rates were compared between the different anatomy and endoscope types. Results: This study included a total of 334 adult patients (665 total ERCPs) with altered anatomy. The pediatric colonoscope was most frequently utilized (32.2%), and the majority of procedures were performed for biliary indications. Enteroscopy success was 82.2% in Roux-en-Y gastric bypass (RYGB), 97% in Billroth II, 91.5% in Whipple, and 93.2% in Roux-en-Y hepaticojejunostomy (RYHJ). Cannulation success was 90.5% in RYGB, 90.5% in Billroth II, 83.6% in Whipple, and 90.6% in RYHJ. Intervention success was 88.2% in Billroth II, 65.1% in RYGB, 81.6% in Whipple, and 87.5% in RYHJ. In patients with RYGB and RYHJ, SBE was utilized most frequently, with rotational enteroscopy having the highest success rates. The overall adverse event rate was 5.1%, with the majority of these being mild in severity. Conclusions: This large retrospective study found ERCP with forward-viewing endoscopes to be safe and effective for a variety of surgically altered anatomy types. Despite recent advances seen with endoscopic ultrasound-guided drainage procedures, this study advocates for ERCP as the initial approach for pancreaticobiliary access in surgically altered anatomy.
Prognostic Impact of the Presence of Barrett’s Esophagus and Intestinal Metaplasia on Esophageal Adenocarcinoma Survival
Fox, Charlie, Friedman, Chloe , Marsh, Megan, McCarter, Martin D. , Kaplan, Jeffrey , Gleisner, Ana , Katzka, David A. , Wani, Sachin , Kolb, Jennifer M. , Scott, Frank I. , Han, Samuel , Lieu, Christopher H.

Foregut: The Journal of the American Foregut Society | August 20, 2021 | Volume: 2 | Issue: 4 | Pages: 356-364

10.1177/26345161211033277 Get It

Background/Aims: Barrett’s esophagus (BE), defined by the presence of intestinal metaplasia (IM) on histology, is thought to be the only identifiable precursor lesion for esophageal adenocarcinoma (EAC). Recent studies have suggested the possibility of an alternate, non-IM associated EAC that is a more aggressive form of EAC with worse survival. Among EAC patients, we aimed to compare survival of patients with and without IM at the time of diagnosis. Methods: This was a retrospective cohort study of all patients with histologic confirmed EAC evaluated at a tertiary care center from 2013 to 2019. Cases were categorized according to the presence or absence of IM on histologic specimens (Group I—IM-EAC and Group II—non-IM-EAC). We compared demographic characteristics, clinical stage, therapy, and survival between the 2 groups using the Chi-square and ANOVA tests (for categorical and continuous variables, respectively). We used Cox proportional hazards regression to determine the association of IM with overall survival, adjusting for sex, age at diagnosis, tumor location, histologic grade, and clinical stage. Results: A total of 475 patients were included in this analysis (mean age 64.8 years [SD 10.8], 89% white) and 109 (23.0%) had no evidence of IM. Compared with IM-EAC (Group I), individuals in the non-IM-EAC group were younger ( P = .01) and had a greater proportion of patients diagnosed with advanced disease (49.5 vs 20.2% for stage 4, P < .001). These patients were less likely to undergo endoscopic therapy alone (0.92% vs 29.78%, P < .001) or surgery alone (0 vs 9.84%, P = .001). On multivariable analysis, the presence of IM-EAC was associated with improved overall survival compared to non-IM-EAC (HR 0.69, 95% CI 0.49-0.96). Additional factors associated with poor survival was increasing stage of diagnosis (HR 6.49: 95% CI 3.77-11.15 for stage 4, HR 2.19: 95% CI 1.25-3.84 for stage 3, HR 2.04: 95% CI 0.98-4.25 for stage 2 compared to stage 1) and more advanced histologic stage (HR 2.00, 95% CI 1.26-3.19) for poorly/undifferentiated compared to well differentiated). Conclusions: EAC without the presence of IM on histology was associated with worse survival compared to those with IM. Future prospective studies with detailed molecular sequencing are required to clarify if 2 separate phenotypes of EAC exist (IM-EAC and non-IM-EAC). If confirmed, this may have significant implications for screening and management strategies.