Michael L. Kochman

Endosonographic differentiation of benign and malignant stromal cell tumors

BACKGROUND Endosonography (EUS) is a valuable technique for diagnosing gastrointestinal stromal cell tumors. However, EUS features that are predictive of malignancy in these tumors have not been defined. METHODS Videotapes and photographs of EUS examinations performed prior to surgical resection of 35 stromal cell tumors (9 malignant) were blindly reviewed by a single examiner. EUS features associated with malignancy were determined. Interobserver agreement in interpreting these features was then measured among a panel of five expert endosonographers who judged EUS videotapes of 35 resected stromal cell tumors (10 malignant). RESULTS Stepwise logistic regression analysis demonstrated that tumor size (diameter > 4 cm), irregular extraluminal border, echogenic foci, and cystic spaces were independently associated with malignancy in stromal cell tumors (p < 0.05). Interobserver agreement for irregular extraluminal border, echogenic foci, and cystic spaces, as measured by mean kappa statistic, was 0.43, 0.39, and 0.28, respectively. For the five experts, the sensitivity for detecting malignancy ranged between 80% to 100% when at least two of the three features were judged to be present. The likelihood of finding malignancy ranged between 0% to 11% for the experts when all three features were judged absent. CONCLUSIONS Tumor size and certain EUS features are useful for predicting malignancy in stromal cell tumors. Absence of these features indicates benign disease. Agreement among experts in interpreting these EUS features is fair to moderate.

EUS compared with CT, magnetic resonance imaging, and angiography and the influence of biliary stenting on staging accuracy of ampullary neoplasms

BACKGROUND Computerized tomography (CT), magnetic resonance imaging (MRI), and transabdominal ultrasound frequently fail to detect ampullary lesions. Endoscopic ultrasound (EUS) is a sensitive modality for detecting and staging ampullary tumors. Accurate staging may be affected by biliary stenting, which is frequently performed in these patients with obstructive jaundice. The present study assessed the accuracy of ampullary tumor staging with multiple imaging modalities in patients with and those without endobiliary stents. METHODS Fifty consecutive patients with ampullary neoplasms from two endosonography centers were preoperatively staged by EUS plus CT (37 patients), MRI (13 patients), or angiography (10 patients) over a 3(1/2) year period. Twenty-five of the 50 patients had a transpapillary endobiliary stent present at the time of endosonographic examination. Accuracy of EUS, CT, MRI, and angiography was assessed with the TNM classification system and compared with surgical-pathologic staging. The influence of an endobiliary stent present at the time of EUS on staging accuracy of EUS was also evaluated. RESULTS EUS was more accurate than CT and MRI in the overall assessment of the T stage of ampullary neoplasms (EUS 78%, CT 24%, MRI 46%). No significant difference in N stage accuracy was noted between the three imaging modalities (EUS 68%, CT 59%, MRI 77%). EUS T stage accuracy was reduced from 84% to 72% in the presence of a transpapillary endobiliary stent. This was most prominent in the understaging of T2/T3 carcinomas. CONCLUSIONS EUS is superior to CT and MRI in assessing T stage but not N stage of ampullary lesions. The presence of an endobiliary stent at EUS may result in underestimating the need for a Whipple resection because of tumor understaging.

Can EUS alone differentiate between malignant and benign cystic lesions of the pancreas

OBJECTIVE:The aim of this study was to evaluate the ability of endoscopic ultrasound (EUS) alone to predict and differentiate malignant from benign cystic lesions of the pancreas.METHODS:From January, 1995, to August, 1999, 98 cases of pancreatic cystic lesions were evaluated by EUS; all of these were originally imaged by cross-sectional modalities that were not diagnostic. Among these, surgical/pathological correlation was available in 48 patients. The original endosonographic images were reviewed by two endosonographers who were blinded to each others interpretation and to the surgical and pathological interpretation. The EUS images were assessed for the presence or absence of the following characteristics: 1) wall, 2) solid component, 3) septae, 4) lymphadenopathy, and 5) number of cysts. These characteristics were then correlated with the surgical and pathological findings and were assessed to determine if any were predictors of the lesion being benign or malignant.RESULTS:For reviewer A, the presence of a solid component by EUS was the only statistically significant predictor of malignancy (odds ratio = 4.73, 95% CI = 1.13–19.68, p = 0.03). However, 61% of patients with benign lesions were also interpreted by EUS to have a solid component. For reviewer B, none of the features were found to be significant predictors of a malignant lesion. When the results of both reviewers were combined, the presence of a solid component was not found to be a statistically significant predictor of malignancy (odds ratio = 1.046, 95% CI = 0.99–1.09, p = 0.07).CONCLUSION:Endosonographic features cannot reliably differentiate between benign and malignant cystic lesions of the pancreas after a nondiagnostic cross-sectional modality.

A review of endoscopic methods of esophageal dilation

Esophageal strictures from a variety of benign and malignant causes require dilation therapy when patients develop symptoms of dysphagia. Dilation can be accomplished using a variety of dilating devices and adjunctive techniques. The approach to management of esophageal strictures is reviewed with a focus on dilation technique and special considerations for various stricture types.

Melanoma in the gastrointestinal tract.

Abstract OBJECTIVE: This article focuses on the clinical, diagnostic, and therapeutic aspects of malignant melanoma metastases to the gastrointestinal (GI) tract. The subject of primary malignant melanoma arising from the GI tract is also discussed. Malignant melanoma is the most common tumor metastatic to the GI tract, and can present with fairly nonspecific symptoms. METHODS: Up to 60% of patients with melanoma are found to have metastases at autopsy. Frequent GI sites of invasion include the small bowel (50%), colon (31.3%), and anorectum (25%), seen in our institution over the past 9 yr. Malignant melanoma is a frequent source of metastases to the gastrointestinal (GI) tract. RESULTS: Herein we report the case of a melanoma masquerading as a rectal polyp. We have also discovered 16 cases of melanoma metastases to the GI tract, at our institution, over the past 9 yr. The most frequent sites included small bowel (50%), colon (31.3%), and anorectum (25%). CONCLUSION: Despite innocuous gastrointestinal symptoms, metastatic melanoma should be a diagnostic consideration in any patient with a history of melanoma.

Guidelines for credentialing and granting privileges for endoscopic ultrasound

Abstract This is one of a series of statements discussing the utilization of gastrointestinal endoscopy in common clinical situations. In preparing this guideline, a MEDLINE literature search was performed, and additional references were obtained from the bibliographies of the identified articles and from recommendations of expert consultants. When little or no data exist from well-designed prospective trials, emphasis is given to results from large series and reports from recognized experts. Guidelines for the appropriate use of endoscopy are based on a critical review of the available data and expert consensus. Controlled clinical studies are needed to clarify aspects of this statement and revision may be necessary as new data appear. Clinical considerations may justify a course of action at variance from these recommendations.

Endoscopic ultrasound-guided real-time fine-needle aspiration biopsy of the pancreas in cancer patients with pancreatic lesions.

BACKGROUND Endoscopic ultrasound (EUS) is an important new tool in the staging of pancreatic malignancies. Using new curved linear-array instruments, real-time fine-needle aspiration biopsy (RTFNA) of pancreatic lesions can be performed. METHODS Forty-five patients with pancreatic lesions (22 males and 23 females) underwent staging with the Olympus EUM-20 (Olympus America Corp, Melville, NY) followed by EUS-RTFNA with the Pentax FG-32PUA (Pentax-Precision Instrument Corp, Orangeburg, NY) and the 22-gauge GIP needle (GIP Medizin Technik, Grassau, Germany). RESULTS EUS tumor stages were as follows: TO, n = 1; T1, n = 8; T2, n = 9; and T3 n = 27. Aspiration attempts were unsuccessful in four patients (two technical failures and two inadequate specimens). The remaining 41 lesions (mean size, 3.3 cm) were aspirated under EUS guidance (median passes, three) and the cytologic diagnoses were 25 definite adenocarcinoma, five suspicious for adenocarcinoma (three subsequently confirmed and two clinical course consistent with adenocarcinoma), and 11 negative for malignancy. Of 11 negatives, two were found to have adenocarcinoma, seven were confirmed benign at surgery (four cystadenomas and three inflammatory), one had a benign pseudocyst, and one had abundant inflammatory cells on RTFNA and follow-up time greater than 12 months with computed tomographic (CT) scans consistent with resolving inflammation. There were no false-positive RTFNAs. There were no procedure-related complications. Among those with diagnostic EUS-RTFNA (91%), the sensitivity for malignancy (confirmed plus suspicious) was 94% and negative predictive value 82%. CONCLUSION EUS-guided RTFNA is a safe and accurate method for performing pancreatic biopsy. It should be considered in patients with suspected pancreatic malignancies in whom a tissue diagnosis is required or when other modalities have failed. EUS-RTFNA allows for local staging and tissue diagnosis in one procedure.

Acute pancreatitis after EUS-guided FNA of solid pancreatic masses: a pooled analysis from EUS centers in the United States

BACKGROUND The aim of this study was to determine the frequency and the severity of pancreatitis after EUS-guided FNA of solid pancreatic masses. A survey of centers that offer training in EUS in the United States was conducted. METHODS A list of centers in which training in EUS is offered was obtained from the Web site of the American Society for Gastrointestinal Endoscopy. Designated program directors were contacted via e-mail. The information requested included the number of EUS-guided FNA procedures performed for solid pancreatic masses, the number of cases of post-procedure pancreatitis, and the method for tracking complications. For each episode of pancreatitis, technical details were obtained about the procedure, including the location of the mass, the type of fine needle used, the number of needle passes, and the nature of the lesion. RESULTS Nineteen of the 27 programs contacted returned the questionnaire (70%). In total, 4909 EUS-guided FNAs of solid pancreatic masses were performed in these 19 centers over a mean of 4 years (range 11 months to 9 years). Pancreatitis occurred after 14 (0.29%): 95% CI[0.16, 0.48] procedures. At two centers in which data on complications were prospectively collected, the frequency of acute pancreatitis was 0.64%, suggesting that the frequency of pancreatitis in the retrospective cohort (0.26%) was under-reported (p=0.22). The odds that cases of pancreatitis would be reported were 2.45 greater for the prospective compared with the retrospective cohort (95% CI[0.55, 10.98]). The median duration of hospitalization for treatment of pancreatitis was 3 days (range 1-21 days). The pancreatitis was classified as mild in 10 cases, moderate in 3, and severe in one; one death (proximate cause, pulmonary embolism) occurred after the development of pancreatitis in a patient with multiple comorbid conditions. CONCLUSIONS EUS-guided FNA of solid pancreatic masses is infrequently associated with acute pancreatitis. The procedure appears to be safe when performed by experienced endosonographers. The frequency of post EUS-guided FNA pancreatitis may be underestimated by retrospective analysis.

Detection of Circulating Pancreas Epithelial Cells in Patients With Pancreatic Cystic Lesions

Hematogenous dissemination is thought to be a late event in cancer progression. We recently showed in a genetic model of pancreatic ductal adenocarcinoma that pancreas cells can be detected in the bloodstream before tumor formation. To confirm these findings in humans, we used microfluidic geometrically enhanced differential immunocapture to detect circulating pancreas epithelial cells in patient blood samples. We captured more than 3 circulating pancreas epithelial cells/mL in 7 of 21 (33%) patients with cystic lesions and no clinical diagnosis of cancer (Sendai criteria negative), 8 of 11 (73%) with pancreatic ductal adenocarcinoma, and in 0 of 19 patients without cysts or cancer (controls). These findings indicate that cancer cells are present in the circulation of patients before tumors are detected, which might be used in risk assessment.

Per-oral endoscopic myotomy white paper summary.

Achalasia is an uncommon esophageal motility disorder in which there is selective loss of inhibitory neurons resulting in loss of peristalsis and failure of adequate relaxation of the lower esophageal sphincter (LES) in response to food bolus. There is no current curative treatment that reverses the pathophysiology of achalasia. The treatment options are aimed at improving the passage of solids and liquids through the gastroesophageal junction (GEJ). The traditional treatment options include surgical myotomy and endoscopic methods that disrupt or weaken the LES, such as endoscopic balloon dilation and botulinum toxin injection (BI). Per-Oral Endoscopic Myotomy (POEM) represents a Natural Orifice Translumenal Endoscopic Surgery (NOTES ) approach to Heller myotomy. Preliminary data suggest that this minimally invasive endoscopic procedure may achieve clinical results similar to those of surgical myotomy. As part of the annual Natural Orifice Surgery Consortium for Assessment and Research (NOSCAR ) meeting held in Chicago in July 2012, a conference was organized to collaboratively review POEM and develop a consensus document on the current status of POEM. An International POEM Survey (IPOEMS) was designed and conducted by the session moderators as part of this NOSCAR initiative to attempt to supplement the scant published literature with current data from POEM early adopters. The survey, which has now been published in This article is being published simultaneously in both Gastrointestinal Endoscopy and Surgical Endoscopy.