Management of Duodenal Neuroendocrine Tumors: Surgical versus Endoscopic Mucosal Resection.

BACKGROUND: Management of duodenal neuroendocrine tumors (DNETs) is not standardized, with smaller lesions (< 1-2 cm) generally treated by endoscopic mucosal resection (EMR) and larger DNETs by surgical resection (SR). This study reviewed how patients were selected for treatment and compared outcomes. PATIENTS AND METHODS: Patients with DNETs undergoing resection were identified through institutional databases, and clinicopathologic data recorded. χ2 and Wilcoxon tests compared variables. Survival was determined by Kaplan-Meier, and Cox regression tested association with survival. RESULTS: Among 104 patients, 64 underwent EMR and 40 had SR. Patients selected for SR had larger tumor size, younger age, and higher T, N, and M stage. There was no difference in progression-free (PFS) or overall survival (OS) between SR and EMR. In 1-2 cm DNETs, there was no difference in PFS between SR and EMR [median not reached (NR), P = 0.1]; however, longer OS was seen in SR (median NR versus 112 months, P = 0.03). In 1-2 cm DNETs, SR patients were more likely to be node-positive and younger. After adjustment for age, resection method did not correlate with survival. Comparison of surgically resected DNETs versus jejunoileal NETs revealed longer PFS (median NR versus 73 months, P < 0.001) and OS (median NR versus 119 months, P = 0.004) DISCUSSION: In 1-2 cm DNETs, there was no difference in survival between EMR and SR after adjustment for age. Recurrences could be salvaged, suggesting that EMR is a reasonable strategy. Compared with jejunoileal NETs, DNETs treated by SR had improved PFS and OS.

Direct endoscopic placement of percutaneous endoscopic gastrostomies with jejunal extension tubes (PEG-J) using ultra-thin endoscopes - long-term outcomes from a U.S. tertiary referral center.

INTRODUCTION: Several techniques for PEG-J tube placement have been described, commonly requiring fluoroscopic guidance and/or fixation of the jejunostomy tube (J-tube) into the small intestine. We describe a modified technique for placing jejunostomy tubes under direct visualization through a PEG with the use of ultra-thin endoscopes and steel guidewire. METHODS: A retrospective study at a single tertiary academic center evaluating patients who underwent PEG-J placement between 2010 and 2020. All PEG tubes were placed with a pull-through technique. The Olympus GIF-N180 endoscope was advanced through the PEG to the jejunum and a Savary-Gilliard guidewire was used for placement of the J-tube extension. RESULTS: Fifty-eight patients underwent PEG-J placement (median age 61 years; women 52%). Surgically altered gastric anatomy was observed in 11 patients (19%). Median procedure time was 44 min for new PEG-J tube placement (range 26-103) and 20 min for placement of a J-tube extension through an existing PEG tube (range 9-86) or gastrostomy tract. Technical success rate was in 100%. Sixty-two repeat procedures were performed for J-tube exchange in 27 patients (46%, range 1-9 per patient), of which 51 procedures (82%) were done using the same technique. The most common indication for tube replacement was tube dysfunction (63%, n = 39). The median procedure time for tube exchange was 20 min (range 2-62). No major adverse events were encountered. CONCLUSION: PEG-J tubes can be placed effectively, rapidly, and safely using an ultra-thin caliber endoscope and a stiff steel wire through the PEG tube or mature gastrostomy site, precluding the need for fluoroscopy or oral access. J-tubes can be easily replaced utilizing the same technique.

Randomized controlled trial comparing the Franseen needle with the Fork-tip needle for EUS-guided fine-needle biopsy.

BACKGROUND AND AIMS: EUS-guided FNA primarily provides cytologic samples. EUS-guided fine-needle biopsy (FNB) with needles that provide histologic specimens may enhance diagnostic yield and facilitate accessory tissue staining. Several different needle designs are currently available and design superiority is unknown. We designed a randomized controlled trial to compare 2 commonly used EUS-FNB needles in their ability to provide histologic tissue samples (primary endpoint) and to reach an accurate diagnosis (secondary endpoint). METHODS: A total of 150 lesions from 134 patients (November 2018 to June 2019) were randomized 1:1 between biopsy with a Franseen needle and a Fork-tip needle. The groups were compared regarding the quality of the tissue samples and diagnostic accuracy. RESULTS: Of 150 lesions, 75 were pancreatic and 75 were other solid lesions in and around the GI tract. There was no statistically significant difference between the Franseen needle and the Fork-tip needle in the yield of adequate histologic samples, 71 of 75 (94.7%) versus 72 of 75 (96%), (P = 1.00), an absolute difference of -1.3% (95% confidence interval [CI], -8.1% to 5.4%). The 2 groups were similar in the diagnostic accuracy of histologic analysis, 64 of 75 (85.3%) versus 68 of 75 (90.7%) (P = .45), absolute difference -5.4% (95% CI, -15.7% to 5%); and in the diagnostic accuracy of combined cytologic and histologic analysis, 65 of 75 (86.7%) versus 69 of 75 (92%) (P = .43), absolute difference -5.3% (95% CI, -15.2% to 4.5%). CONCLUSIONS: There was no significant difference in the performance of the Franseen needle versus the Fork-tip needle. Both needles achieved a high yield of histologic tissue samples and high diagnostic accuracy. (Clinical trial registration number: NCT03672032.).

[Pancreatic Mass or Cyst? Diagnostic Dilemma].

A santorinicele is a rare anomaly defined as focal cystic dilation of the terminal portion of the dorsal pancreatic duct at the minor papilla. Importantly this anomaly has been suggested as a possible cause of relative stenosis of the minor papilla. This anomaly has been associated with pancreatic divisum and recurrent acute pancreatitis. Magnetic resonance imaging/magnetic resonance cholangiopancreatography and endoscopic ultrasound (EUS) are the main diagnostic modalities. Endoscopic minor papilla sphincterotomy has been shown to improve pain and quality of life in patients with this anomaly presenting with recurrent pancreatitis. We present a case of a single episode of pancreatitis who underwent EUS for evaluation of possible pancreatic mass leading to a diagnosis of santorinicele and complete pancreatic divisum. We attempt to describe this anomaly, diagnostic approach, and management options.

Per oral endoscopic myotomy: early experience and safety of a multispecialty approach.

BACKGROUND: Per oral endoscopic myotomy (POEM) has gained increasing popularity for treating achalasia. A multidisciplinary approach may allow safe and early adoption of POEM into clinical practice. MATERIALS AND METHODS: We performed a retrospective review of our initial POEM cases. All procedures were performed by a team of interventional gastroenterologist and thoracic surgeon. We analyzed demographics, comorbidities, achalasia subtypes, length of hospital stay, duration of surgery, morbidity, mortality, length of myotomy, preoperative and postoperative Eckardt scores. RESULTS: Thirty-one consecutive patients underwent POEM during the 24-month period from January 2014 to December 2015. Eighteen patients (58%) had prior non-operative interventions. Average duration of follow-up was 9.6 months. Seventeen patients (66.8%) had follow-up of 12 months and longer. Average preoperative Eckardt score was 6.3 (3-10), median 6. Average postoperative Eckardt score was 1.4 (0-8), median 1, in 1 month and an average 2.2, median 1, in 1 year. Patients with type III achalasia were most refractory to treatment, while patients with type II had the best results. Average LOS was 1.3 days (1-5), median 1 day. Average DOS was 106 min (60-148), median 106. Average LOM was 13 cm (10-15), with median of 13 cm. We had one 30-day mortality secondary to coronary artery disease. Four patients had prior Heller myotomies and underwent a posterior myotomy during POEM, with outcomes similar to patients with no prior myotomy. CONCLUSIONS: We demonstrated safety and efficiency of a multispecialty approach for achalasia with POEM with a low rate of complications.

A novel technique for the treatment of radiation-induced acquired esophageal atresia in patients with head and neck cancer.

Background and Aims: Dysphagia is a common complaint for patients after radiation therapy for head and neck cancer. Chronic dysphagia ensues when the radiation-induced injury matures into a fibrotic stricture, with the severity of symptoms paralleling the degree of stenosis. Most patients experience progressive dysphagia that prompts medical attention before complete esophageal obliteration. Rarely, patients present late with inability to clear their secretions because of complete obstruction, also termed acquired atresia. These patients represent a challenge and require aggressive and unconventional interventions to reestablish lumenal patency. Using a case series, we hereby describe a novel yet simple technique to treat patients with acquired esophageal atresia. Methods: Five patients with head and neck cancer in various stages who all underwent nonsurgical treatment with definitive chemotherapy and radiation along with enteral feeding tube placement prior to/during treatment presented with acquired esophageal atresia. All patients underwent an EGD to reestablish lumenal patency. This was accomplished with gentle pressure that was applied in a to-and-fro semi-circular rotational manner as if pushing a corkscrew and twisting it in alternating clockwise and counterclockwise manner. Results: In all cases we were able to reestablish esophageal lumenal patency with a single procedure. There were no adverse events. Four of the 5 patients required additional dilations for symptomatic management. However, all patients' esophageal lumens remained patent. Conclusions: We describe a novel yet simple technique to treat acquired esophageal atresia after radiation for head and neck cancer. This technique allows for generous dilation yielding complete resolution of the stenosis in a single session. When our approach is used, the patient can be discharged home the same day and resume immediate oral intake.

Efficacy and safety of EMR to completely remove Barrett's esophagus: experience in 41 patients.

BACKGROUND: EMR is typically used to remove focal abnormalities of the esophageal mucosa. However, larger areas of Barrett's esophagus (BE) can be resected through side-by-side resections. OBJECTIVE: To assess the efficacy and safety of EMR to completely remove BE. DESIGN: Retrospective, single-center study. SETTING: University of Iowa Hospitals and Clinics. PATIENTS: Between January 2006 and December 2010, 46 patients underwent EMR for complete removal of BE. Three were lost to follow-up, one died of unrelated causes before completion, and one was still undergoing EMR treatment at the conclusion of the study. The remaining 41 patients were included for analysis. The worst histologic grade was low-grade dysplasia in 4 patients, high-grade dysplasia without cancer in 26 patients, and high-grade dysplasia with superficial adenocarcinoma in 11 patients. BE was circumferential in 65.9% of cases, and the mean (± SD) length was 3.3 ± 2.3 cm. INTERVENTION: EMR was performed by using a cap (n = 4), a multiband ligator device (n = 31), or both (n = 6), with a mean (± SD) of 2.4 ± 1.2 sessions per patient. MAIN OUTCOME MEASUREMENTS: Remission rates and complications. RESULTS: Remission of high-grade dysplasia and cancer, all dysplasia, and all BE was achieved in 94.6%, 85.4%, and 78.0%, respectively. Complications included minor bleeding (31.7%), perforations (4.9%), and strictures (43.9%). All complications were managed conservatively. LIMITATIONS: Retrospective design. CONCLUSION: Complete removal of BE with EMR is effective but associated with a high complication rate, which is mainly related to stricture formation. This needs to be considered when choosing between available treatment modalities.

What should be done with a dilated bile duct?

Current methods for imaging the biliary tree include ultrasound, CT, MRI, endoscopic retrograde cholangiography, and endoscopic ultrasound (EUS). Bile duct abnormalities may be identified during evaluation of patient symptoms or laboratory abnormalities, or incidentally during imaging for another problem. Biliary dilatation, when identified, may be separated into obstructive or nonobstructive causes. Clinical presentation should guide decisions on which, if any, additional investigations are necessary. Choledocholithiasis is the most common cause of obstructive dilatation and frequently requires decompression. Nonobstructive causes include cystic dilatation, aging, and possibly post-cholecystectomy state. Data are limited regarding the yield of further investigations in patients with incidentally identified modest ductal dilatation without symptoms or laboratory abnormalities. Additional investigations are more likely to identify clinically relevant findings in patients with more pronounced dilatation. EUS is highly accurate, low-invasive, and useful in this setting, whereas ERC should be reserved for cases likely to require therapeutic intervention.

Modified Endoscopic Ultrasound Needle to Obtain Histological Core Tissue Samples: A Retrospective Analysis.

BACKGROUND/AIMS: Endoscopic ultrasound (EUS)-guided fine-needle aspiration is very effective for providing specimens for cytological evaluation. However, the ability to provide sufficient tissue for histological evaluation has been challenging due to the technical limitations of dedicated core biopsy needles. Recently, a modified EUS needle has been introduced to obtain tissue core samples for histological analysis. We aimed to determine (1) its ability to obtain specimens for histological assessment and (2) the diagnostic accuracy of EUS-guided fine-needle biopsy (EUS-FNB) using this needle. METHODS: We retrospectively analyzed consecutive cases of FNB using modified EUS needles for 342 lesions in 303 patients. The cytology and histological specimens were analyzed. Diagnostic accuracy was calculated. RESULTS: Adequate cytological and histological assessment was possible in 293/342 (86%) and 264/342 (77%) lesions, respectively. Diagnostic accuracy of the cytological specimen was 294/342 (86%) versus 254/342 (74%) for the histological specimen (p<0.01). Diagnostic accuracy of the combined cytological and histological assessment was 323/342 (94.4%), which was significantly higher than that of both histology alone (p<0.001) and cytology alone (p=0.001). CONCLUSION: EUS-FNB with the modified EUS needle provided histologic tissue cores in the majority of cases and achieved excellent diagnostic accuracy with few needle passes.

Experience with Peroral Endoscopic Myotomy for Achalasia and Spastic Esophageal Motility Disorders at a Tertiary U.S. Center.

BACKGROUND/AIMS: Peroral endoscopic myotomy (POEM) is a novel procedure for the treatment of achalasia and spastic esophageal disorders. Experience with POEM is limited, but its reported outcomes are excellent. It is deemed safe even for patients with prior interventions. METHODS: This retrospective review included patients who underwent POEM at a tertiary US center. POEM was performed in a multidisciplinary approach by advanced endoscopists and foregut surgeons. Clinical success was defined as a post-POEM Eckardt score ≤3. RESULTS: A total of 125 patients were included. Median follow-up period was 18 months (interquartile range, 10-22 months). Clinical success was achieved in 92% of patients and persisted at 12 months in 88% of patients. Mucosal barrier failure (MBF) occurred in 7 patients, 2 of whom required surgical intervention. MBF was more common in patients with prior laparoscopic Heller myotomy (19% vs. 3%, p=0.015). MBF requiring surgical intervention occurred early in the learning curve. CONCLUSION: POEM is safe and effective in the treatment of achalasia and spastic esophageal disorders even after failed prior interventions.

For patients with predicted low risk for choledocholithiasis undergoing laparoscopic cholecystectomy, selective intraoperative cholangiography and postoperative endoscopic retrograde cholangiopancreatography is an effective strategy to limit unnecessary procedures.

BACKGROUND: There is debate about whether intraoperative cholangiography (IOC) should be performed routinely or selectively during laparoscopic cholecystectomy (LC) in patients with suspected choledocholithiasis. The timing of endoscopic retrograde cholangiopancreatography (ERCP) in these patients also is an issue. We reviewed the experience in our center, where a management algorithm limiting ERCP in relation to LC was adopted. METHODS: We retrospectively reviewed every LC performed by one surgeon during 6 years and the related ERCPs. RESULTS: A total of 264 LCs were performed. In 30 patients, stones were cleared or excluded by preoperative ERCP. In the remaining 234 LCs, 31 of 34 IOCs were successfully performed. Two of 31 IOCs were positive for bile duct stones; stone removal was successful in each patient at subsequent ERCP. Only 10 of 201 patients who did not have IOC required postsurgical ERCP within 10 weeks of LC, 3 of whom had common bile duct stones at ERCP. CONCLUSIONS: For patients who underwent LC, we performed selective IOC with postoperative ERCP for positive studies. Review of our experience using this algorithm showed it to be a powerful tool in limiting unnecessary ERCPs. Our data suggest that routine preoperative ERCP cannot be justified. Selective IOC during LC misses relatively few cases of biliary stones; these can be managed quickly by experienced endoscopists.

EUS-guided Trucut biopsies may enable the diagnosis of lymphoepithelial cysts of the pancreas. Report of two cases.

CONTEXT: Lymphoepithelial cysts are rare benign lesions of the pancreas. Endoscopic ultrasound guided fine needle aspiration (FNA) has reportedly been helpful in reaching a diagnosis of lymphoepithelial cyst. In cases where it may be difficult to obtain a diagnosis using FNA a histological sample may be obtained using EUS guided Trucut biopsy. CASE REPORTS: We describe two cases of lymphoepithelial cysts where a diagnosis of lymphoepithelial cyst was made using EUS guided Trucut biopsy. CONCLUSION: In some case, lymphoepithelial cysts may present a diagnostic dilemma. EUS with FNA and Trucut biopsy may enable the clinician to make a definitive diagnosis.

Focal or diffuse "fullness" of the pancreas on CT. Usually benign, but EUS plus/minus FNA is warranted to identify malignancy.

CONTEXT: The role of EUS to evaluate subtle radiographic abnormalities of the pancreas is not well defined. OBJECTIVE: To assess the yield of EUS+/-FNA for focal or diffuse pancreatic enlargement/fullness seen on abdominal CT scan in the absence of discrete mass lesions. DESIGN: Retrospective database review. SETTING: Tertiary referral center. PATIENTS AND INTERVENTIONS: Six hundred and 91 pancreatic EUS exams were reviewed. Sixty-nine met inclusion criteria of having been performed for focal enlargement or fullness of the pancreas. Known chronic pancreatitis, pancreatic calcifications, acute pancreatitis, discrete mass on imaging, pancreatic duct dilation (greater than 4 mm) and obstructive jaundice were excluded. MAIN OUTCOME MEASUREMENT: Rate of malignancy found by EUS+/-FNA. RESULTS: FNA was performed in 19/69 (27.5%) with 4 new diagnoses of pancreatic adenocarcinoma, one metastatic renal cell carcinoma, one metastatic colon cancer, one chronic pancreatitis and 12 benign results. Eight patients had discrete mass lesions on EUS; two were cystic. All malignant diagnoses had a discrete solid mass on EUS. CONCLUSIONS: Pancreatic enlargement/fullness is often a benign finding related to anatomic variation, but was related to malignancy in 8.7% of our patients (6/69). EUS should be strongly considered as the next step in the evaluation of patients with focal enlargement of the pancreas when clinical suspicion of malignancy exists.

Peroral Endoscopic Myotomy Is Feasible and Safe in a Gastric Bypass Population.

BACKGROUND: Obesity is public health problem of epidemic proportions. Esophageal dysmotility including achalasia is more commonly seen in an obese population. Standard therapy for achalasia can be complicated by hepatomegaly and a post-surgical anatomy in a pre- and post-bariatric population. Peroral endoscopic myotomy (POEM) has not been adequately studied in this population. METHODS: A retrospective review of a prospectively collected database was completed. Patients who had undergone a Roux-en-y gastric bypass (RYGB) prior to or following a POEM were enrolled. Patient demographics, operative information and post-operative course data was collected. RESULTS: Six patients underwent POEM prior to or after RYGB. There were no peri-operative complications with an average length of stay of 1.2 days. Five patients experienced a clinical success with excellent symptom resolution. The one failure was in the setting of type III achalasia, but did have objective evidence of lower esophageal sphincter (LES) relaxation post-operatively. CONCLUSION: POEM in the setting of bariatric surgery is safe and feasible. The potential increase in GERD following POEM is obviated by RYGB anatomy. In an obese individual, a staged POEM prior to or following a RYGB is an appropriate treatment algorithm for obese and achalasia.

The value of touch imprint cytology in EUS-guided Trucut biopsy.

BACKGROUND: EUS-guided Trucut biopsy (TCB) enables the acquisition of tissue cores for histologic assessment. Touch imprint cytology (TIC) can be performed at the time of a biopsy to assess the adequacy of the sample; however, limited information is available on the diagnostic value of TIC of these specimens. OBJECTIVE: To investigate the diagnostic accuracy of TIC compared with a TCB. PATIENTS AND DESIGN: Consecutive EUS-guided TCB and TIC (n = 109) were retrospectively and independently reviewed by a surgical pathologist (for the TCB) and a cytopathologist (for TIC) blinded to the final diagnoses. SETTING: University of Iowa Hospitals and Clinics, Iowa. MAIN OUTCOME MEASUREMENTS: Diagnostic accuracy of a TCB, TIC, and combined TCB + TIC. RESULTS: The diagnostic accuracy of a TCB was 92.7% (95% CI, 83.1%-97.3%), TIC was 82.6% (95% CI, 74.3%-88.6%), and TCB + TIC was 95.4% (95% CI, of 89.4%-98.3%). The diagnostic accuracy of a TCB alone was superior to TIC alone (P = .038); a TCB was diagnostic in 14 cases that were nondiagnostic by TIC. The addition of TIC allowed for the identification of 3 malignancies (2.8%) that were not identified on TCB alone. In 22 cases, TIC was considered diagnostic, but a TCB provided additional specific diagnostic information. LIMITATIONS: Retrospective study and relatively low numbers. CONCLUSIONS: TIC is a valuable tool for use in a EUS-guided TCB; TIC is independently diagnostically accurate, which allows for confidence in a rapid preliminary diagnosis, and it provides additional diagnostic value when combined with TCB.

Underwater endoscopic mucosal resection: an alternative treatment for large colorectal polyp removal.

BACKGROUND: Large sessile/flat colonic polyps are traditionally removed by lift polypectomy. Underwater endoscopic mucosal resection (UEMR) is a novel technique where air is suctioned out and replaced by water to decompress the colon so that the flat lesions assumes a more polypoid shape facilitating its removal with the standard snare resection. We report the feasibility and safety in our series of patients utilizing this technique. METHODS: A retrospective, observational study of all patients who underwent removal of large colonic polyps (>10 mm) over a period of 3 years (January 2012 to January 2015) at a tertiary care center by UEMR were included in the study. RESULTS: A total of 102 polyps were removed in 93 adult patients using UEMR. The mean age of patients was 64.7±9.7 years. The average number of polyps per patient was 1.84±1.3 with a range of 1-7. The range of the polyp size was 10 to 60 mm. The mean size of the polyp was 20.4±9.4 mm, median size 26.9±9.4 mm. Ninety-two (90.2%) were removed in piecemeal fashion and ten (9.8%) were removed en bloc. Delayed bleeding occurred in seven (9.7%) patients. CONCLUSIONS: In this largest series on UEMR, we report the feasibility and safety of this procedure. Future randomized trials comparing this technique versus standard lift polypectomy technique will further elucidate the benefit of one over other.

Endoscopic Cyanoacrylate Glue Injection in Management of Gastric Variceal Bleeding: US Tertiary Care Center Experience.

BACKGROUND/AIMS: Although endoscopic cyanoacrylate glue injection (ECGI) is recommended as first-line treatment for bleeding gastric varices (GV) there is still limited experience with this method in the US. Our aim was to analyze our 10-year experience of ECGI for treatment and prophylaxis of gastric variceal bleeding. METHODS: Records of patients undergoing ECGI of GV at our US tertiary care center between 6/2005 and 5/2015 were reviewed. Assessed outcomes were primary hemostasis, early rebleeding during hospitalization, recurrent bleeding during follow-up, eradication and recurrence of GV. RESULTS: Prophylactic ECGI was performed in 16 patients with large GV. Eradication was achieved in 15 (94%). During the median follow-up of 27 (IQR 7-47) months, 4 patients (26.6%) had variceal bleeding; all were treated successfully with ECGI. Fifty-seven patients underwent ECGI for GV bleeding. Primary hemostasis was achieved in all. Early rebleeding occurred in 2 (3.5%) and durable hemostasis could not be achieved. Follow-up beyond initial hospitalization was available in 41 patients. Bleeding recurred in 8 (19.5%) patients during a median follow-up of 12 (IQR, 3-51) months. Eradication of GV was achieved in 92% of patients but recurrent varices were found in 44% during a median follow up period of 33 months. CONCLUSION: ECGI is effective in achieving hemostasis of bleeding GV and their eradication. Recurrent bleeding and recurrence of varices after complete obliteration however are not infrequent and continued surveillance is advisable.

Utility of endoscopic ultrasound in pancreatitis: a review.

The close proximity of the endoscopic ultrasound probe to the pancreas results in superior spatial resolution compared to CT scan and MRI. In addition, endoscopic ultrasound (EUS) is a minimally invasive procedure that does not share the relatively high complication rate of ERCP. Due to these advantages, EUS has evolved into an important technique to assess pancreatobiliary disease. This review will discuss the role of EUS in patients with pancreatitis. The indications can be divided into acute pancreatitis and chronic pancreatitis. In acute pancreatitis, EUS is used to determine the etiology; in suspected chronic pancreatitis it is helpful to establish the diagnosis. Lastly, this review will discuss biliary pancreatitis with suspicion for persistent choledocholithiasis.

Endoscopic ultrasound with tissue sampling is accurate in the diagnosis and subclassification of gastrointestinal spindle cell neoplasms.

BACKGROUND AND OBJECTIVES: Mesenchymal (spindle cell) neoplasms (SCN) of the gastrointestinal (GI) tract are an important subtype of subepithelial lesions that need subclassification to assess their malignant potential. Reported success rates of accurate subclassification with endoscopic ultrasound (EUS)-guided biopsies are variable. Our goal was to analyze our experience using EUS-guided TruCut biopsy (EUS-TCB) in the majority of patients. METHODS: Retrospective analysis in patients who underwent EUS with biopsies for suspected SCN at our tertiary referral center between 2004 and 2013. RESULTS: A total of 146 patients with suspected SCN underwent EUS with tissue acquisition. Thirteen patients were excluded from analysis because tissue acquisition established a definite diagnosis other than SCN. In the remaining 133 patients, tissue acquisition was diagnostic of SCN in 118 (88.7%) and nondiagnostic in 15 (11.3%). Subclassification based on immunohistochemistry (IHC) was possible in 109 of the 133 cases (81.9%). The final diagnosis was GI stromal tumor in 64, leiomyoma in 39, and schwannoma in 6 cases. The percentage of patients who were subclassified by the various EUS-guided techniques together was 72.18%, and the percentage of patients who were subclassified specifically with EUS-TCB was 61.65%. Tissue specimens that enabled a specific diagnosis based on histological or cytological characteristics in conjunctions with IHC were obtained with EUS core biopsy in 83 (TCB in 82 and ProCore needle biopsy in 1), fine-needle aspiration in 13, mucosal resection in 10, and forceps biopsies (bite-on-bite) in 3 cases. CONCLUSION: EUS with endoscopic tissue acquisition is accurate in the diagnosis and subclassification of SCN. In experienced hands, the EUS-TruCut needle is a valuable tool with a high success rate for this indication.