Allison R. Schulman’s research while affiliated with Concordia University Ann Arbor and other places

Purpose Endoscopic ultrasound with fine needle biopsy (EUS-FNB) has not been well studied in pancreatic cystic lesions (PCLs). This study evaluates the diagnostic performance of EUS-FNB for PCLs and its impact on management decisions. Methods We conducted a single-center, retrospective study of patients who had EUS-FNB between March 2016 and February 2024. We included patients with ≥ 6-month follow-up and excluded those with a solid pancreatic mass. We obtained clinical, radiologic, endoscopic, surgical, laboratory, and pathology data from chart review. We evaluated: (A) diagnostic yield; (B) predictors of diagnostic FNB; (C) diagnostic accuracy compared to surgical histopathology; (D) appropriateness of management decisions; and (E) adverse events. We compared the appropriateness of management decisions between diagnostic and non-diagnostic FNB. Results 100 subjects underwent EUS-FNB for PCLs (56% microcystic or with mural nodule). FNB yielded a histologic diagnosis in 60% of sampled lesions. Performing 2 or more needle passes was the only significant predictor of a diagnostic FNB (p = 0.02). Compared to surgical histopathology (n = 21), FNB needles highly accurately diagnosed specific cyst types (IPMN = 85.7%, MCN = 90.5%, SCA = 95.2%, NET = 95.2%, SPN = 100%) and malignant PCLs (accuracy = 81.0%; specificity = 100%; sensitivity = 72.7%). There was a 7.2-fold increase of appropriate management decisions when FNB was diagnostic vs. non-diagnostic (p < 0.001). This was due to improvement in surveillance discontinuation for benign cysts and in appropriate surgical resection for malignant PCLs (p < 0.001). Post-FNB pancreatitis occurred in 4% of patients. Conclusion EUS-FNB accurately diagnoses different PCL types and their degree of neoplasia, leading to more appropriate management decisions. Future prospective studies are needed to confirm these findings.

Background & Aims: Intraductal papillary mucinous neoplasms (IPMNs) are pancreatic cysts that represent one of the few radiologically identifiable precursors to pancreatic ductal adenocarcinoma (PDAC). Though the IPMN-bearing patient population represents a unique opportunity for early detection and interception, current guidelines provide insufficient accuracy in determining which patients should undergo resection versus surveillance, resulting in a sizable fraction of resected IPMNs only harboring low-grade dysplasia, suggesting that there may be overtreatment of this clinical entity. Methods: To investigate the transcriptional changes that occur during IPMN progression, we performed spatial transcriptomics using the Nanostring GeoMx on patient samples containing the entire spectrum of IPMN disease including low-grade dysplasia, high-grade dysplasia, and IPMN-derived carcinoma. Single cell RNA sequencing was performed on side branch and main duct IPMN biospecimens. Results: We identified a subpopulation of histologically low-grade IPMN epithelial cells that express malignant transcriptional features including KRT17, S100A10 and CEACAM5, markers that are enriched in PDAC. We validated and refined this high-risk gene signature by integrating our ST analysis with an external ST dataset containing a larger number of IPMN samples including non-tumor bearing IPMN (i.e. low-grade IPMN in isolation). We confirmed the presence of the KRT17+ population using immunofluorescence on a large cohort of patient tissues, revealing a widespread but patchy distribution of KRT17+ cells in histologically low-grade IPMN. Conclusions: Our study demonstrates that KRT17 marks a distinct transcriptional signature in a subpopulation of epithelial cells within histologically low-grade IPMN. This population of cells likely represents a transitional state of histologically low-grade epithelial cells undergoing progression to a higher grade of dysplasia and thus may represent a higher risk of progression to carcinoma.

Abdominal pain is common in patients who have undergone bariatric surgery and perhaps most common in Roux-en-Y gastric bypass (RYGB). It is estimated that over one-third of patients with RYGB present with abdominal pain, although this is likely a gross underestimate as studies investigating this have been performed in a closed setting; patients oftentimes will change physician providers or be admitted to other hospitals. A standard abdominal pain workup evaluating etiologies unrelated to bariatric surgery should be pursued as appropriate. Such conditions include but are not limited to cardiovascular disease, pancreatitis, appendicitis, functional pain, splenic infarcts or abscesses, pulmonary processes, vascular evaluation for what would be considered an atypical presentation.

Background and study aims Gastric access temporary for endoscopy (GATE) via endoscopic ultrasound-guided stent placement between the gastric pouch/jejunum and remnant stomach is used in Roux-en-Y gastric bypass (RYGB) to facilitate endoscopic retrograde cholangiopancreatography or other maneuvers. This study aimed to identify radiographic predictors of GATE failure and intraprocedure reasons for aborting. Patients and methods Patients undergoing GATE were matched 3:1 on procedure success. Features indicating quality of the transgastric window were collected including: 1) gastric pouch/blind limb length; 2) location of remnant stomach relative to pouch or blind/roux limb; 3) pouch orientation; 4) remnant orientation; 5) length of contact; 6) tissue thickness; and 7) presence of poor contact (calcification, surgical material, intervening vasculature). Primary outcome was radiographic criteria associated with GATE failure. Secondary outcomes were endoscopic, endosonographic, and fluoroscopic intraprocedure reasons for aborting GATE. Results Forty patients (30 successful, 10 aborted, 82.5% female) who underwent GATE were included. Mean (±SD) age and time since RYGB were 62.8±11.9 and 15.1±8.6 years, respectively. There were no group demographic differences. The cumulative number of contact-related risk factors was associated with GATE failure (OR 26.1, 95% CI 0.004–0.337; P =0.004). Two or more factors increased the likelihood of GATE failure ( P <0.05). Echoendoscope angulation/tip deflection, intervening vasculature, distance to remnant stomach, rapid emptying and/or insufficient filling of contrast were reported in cases of GATE failure. Conclusions Radiographic features may predict GATE failure including intervening vasculature or insufficient contact between gastric pouch/blind limb and remnant. Patients demonstrating these features may benefit from alternative treatment approaches early in management.