Vu Kwan

A prospective randomized trial of cannulation technique in ERCP: effects on technical success and post-ERCP pancreatitis

BACKGROUND AND STUDY AIMS Inadvertent injection of contrast agent into the pancreatic duct is believed to be an important contributor to pancreatitis occurring after endoscopic retrograde cholangiopancreatography (post-ERCP pancreatitis, PEP). Our aim was to examine whether primary deep biliary cannulation with a guide wire is associated with a lower rate of PEP than conventional contrast-assisted cannulation. PATIENTS AND METHODS From August 2003 to April 2006 all patients with an intact papilla who were referred for ERCP were eligible. Patients with pancreatic or ampullary cancer were excluded. Patients were randomized to undergo sphincterotomy biliary cannulation using either contrast injection or a guide wire. The ERCP fellow attempted initially for 5 minutes. If unsuccessful, the consultant attempted for 5 minutes using the same technique, followed by crossover to the other technique in the same sequence and then needle-knife sphincterotomy where appropriate. Patients were assessed clinically after the procedure, then followed up with telephone interviews after 24 hours and 30 days, and serum amylase and lipase tests after 24 hours. RESULTS Out of 1654 patients undergoing ERCP, 413 were included in the study. PEP occurred in 29/413 (7.0 %): 16 in the guide-wire arm, 13 in the contrast arm ( P = 0.48). The overall cannulation success rate was 97.3 %. Cannulation was successful without crossover in 323/413 patients (78.2 %): 167/202 (81.4 %) in the guide-wire arm and 156/211 (73.9 %) in the contrast arm ( P = 0.03). Multivariate analysis demonstrated female sex (OR = 2.7, P = 0.04), suspected sphincter of Oddi dysfunction (OR = 5.5, P = 0.01), and complete filling of the pancreatic duct with contrast agent (OR = 3.5, P = 0.02) to be independently associated with PEP. The risk of PEP increased incrementally with each attempt at the papilla (OR 1.4 per attempt, P = 0.04) to greater than 10 % after four or more attempts. CONCLUSIONS The guide-wire technique improves the primary success rate for biliary cannulation during ERCP but does not reduce the incidence of PEP compared to the conventional contrast technique. The incidence of PEP increases incrementally with each attempt at the papilla.

Endoscopic Resection for Barrett's High-Grade Dysplasia and Early Esophageal Adenocarcinoma: An Essential Staging Procedure With Long-Term Therapeutic Benefit

OBJECTIVES: Patients with Barretts high‐grade dysplasia (HGD) or early esophageal adenocarcinoma (EAC) that is shown on biopsy alone continue to undergo esophagectomy without more definitive histological staging. Endoscopic resection (ER) may provide more accurate histological grading and local tumor (T) staging, definitive therapy, and complete Barretts excision (CBE); however, long‐term outcome data are limited. Our objective was to demonstrate the effect on histological grade or local T stage, efficacy, safety and long‐term outcome of ER for Barretts HGD/EAC and of CBE in suitable patients. METHODS: This prospective study at two Australian academic hospitals involved 75 consecutive patients over 7 years undergoing ER for biopsy‐proven HGD or EAC, using multiband mucosectomy or cap technique. In addition, CBE by 2–3‐stage radical mucosectomy was attempted for all Barretts segments ≤3 cm in length in patients aged <75 years with minimal comorbidities. RESULTS: Biopsy histology showed HGD in 89% of patients and EAC in 11%. However, ER histology resulted in altered grading or staging in 48% of patients (down 28%, up 20%), with HGD in 53%, low‐grade dysplasia (LGD) in 19%, mucosal adenocarcinoma in 13%, submucosal adenocarcinoma in 9%, and no dysplasia in 4% of patients. The CBE success rate was 94%. Complications were one aspiration (hospitalization with full recovery) and six strictures successfully dilated endoscopically. During the mean follow‐up of 31 months (range 3–89), there was no recurrence at ER sites, 11% developed metachronous lesions and five patients underwent esophagectomy for ER‐demonstrated submucosal invasion. Esophagectomy specimens were T0N0M0 in three and T1N0M0 in two patients. There were no deaths due to adenocarcinoma. CONCLUSIONS: ER alters histological grade or local T stage in 48% of patients and dramatically reduces esophagectomy rates by providing safe and effective therapy. ER has a high success rate (94%) for CBE in short segment Barretts esophagus.

Endoscopic necrosectomy of pancreatic necrosis: a systematic review

AimTo review the current status of the novel technique of endoscopic necrosectomy in the management of pancreatic necrosis after acute pancreatitis.MethodsStudies were identified by searching Medline, PubMed and Embase databases for articles from January 1990 to December 2009 using the keywords “acute pancreatitis”, “pancreatic necrosis” and “endoscopy”. Additional papers were identified by a manual search of the references from the key articles. Case series of fewer than five patients and case reports were excluded.ResultsIndications, techniques and outcomes of endoscopic necrosectomy were analysed. There were no randomised controlled trials identified. Ten case series were included in this analysis. There were a total of more than 1,100 endoscopic necrosectomy procedures in 260 patients with pancreatic necrosis. One hundred fifty-five were proven to be infected necrosis on culture. The overall mortality rate was 5%. The mean procedure-related morbidity rate was 27%. The rate of complete resolution of pancreatic necrosis with the endoscopic method alone was 76%.ConclusionsEndoscopic necrosectomy is a safe and effective treatment option in selected patients with pancreatic necrosis after acute pancreatitis. Future studies will be required to further define the selection criteria and the techniques for the endoscopic procedure.

Succinylated gelatin substantially increases en bloc resection size in colonic EMR: a randomized, blinded trial in a porcine model

BACKGROUND Succinylated gelatin (SG) is an inexpensive colloid that may combine ease of use with the advantages of a colloid to potentially increase EMR specimen size, leading to a higher rate of en bloc resection. OBJECTIVE To evaluate the safety, efficacy, and impact on EMR specimen size of SG as a submucosal (s.m.) injectant in comparison with normal saline solution (NS). DESIGN Randomized, blinded, controlled trial conducted with Animal Ethics Committee approval. SETTING Academic hospital. SUBJECTS Ten swine. INTERVENTIONS Sixty EMRs (30 using SG vs 30 using NS as 3 paired experiments per animal) of the largest possible en bloc snare resection of normal colonic mucosa after s.m. injection of a fixed volume of either SG or NS. MAIN OUTCOME MEASUREMENTS EMR specimen size, duration of s.m. cushion, duration of procedure, ratio of vertical elevation to lateral spread of injectant, ease of resection, adverse effects, perforation, histopathology of EMR sites in colectomy specimens at necropsy (for inflammatory cell content, depth of ulceration, and vascular or ischemic changes). RESULTS The mean subject weight was 53 kg. The mean EMR specimen dimensions and surface area were significantly larger with SG (length 37 vs 31 mm, P = .031; width 32 vs 26 mm, P = .022; surface area 9.5 cm(2) vs 6.7 cm(2), P = .044, respectively). The median s.m. cushion duration was 60 minutes with SG versus 15 minutes with NS (P = .005). The median procedure duration with SG was 2.6 minutes vs 2.5 minutes with NS (P = .515). The ratio of vertical elevation to lateral spread of injectant (mean score on a 3-point scale) was 3 with SG versus 2 with NS (P = .228). Ease of resection score (mean score on a 10-point scale) was 8 with SG versus 7 with NS (P = .216). There were no systemic adverse effects, hypersensitivity reactions, or bleeding episodes. There were 2 perforations (treated with clips) with SG and 1 with NS (P = 1.0). Blinded histopathologist assessment of necropsy colectomy specimens did not identify any significant differences between SG and NS EMR sites. LIMITATIONS Animal study. CONCLUSIONS SG is safe and results in a 42% increased surface area for en bloc EMR. Given its other favorable properties, it represents a significant step toward defining the ideal EMR solution.

MINOR PAPILLA SPHINCTEROTOMY FOR PANCREATITIS DUE TO PANCREAS DIVISUM

Background:  Pancreas divisum (PD) is the commonest congenital pancreatic abnormality and is implicated as a cause of acute recurrent pancreatitis (ARP). We report our experience in minor papilla sphincterotomy (MPS) for this condition. Studies published at present have not examined MPS as the primary treatment method in a homogenous (i.e. only those with ARP) patient group.

Severity of initial stent angulation predicts reintervention after successful palliative enteral stenting for malignant luminal obstruction.

Background and Aim:  Recurrent stent obstruction necessitating reintervention is problematic and incompletely understood. The aim of the present study was to identify factor(s) predisposing to reintervention.

Advances in gastrointestinal endoscopy

Gastrointestinal endoscopy has undergone a remarkable expansion in its capabilities as a result of sophisticated technological advances in recent years. New imaging technologies, novel ablation and resection techniques, cutting‐edge endoscope development and creative extraluminal applications have taken gastrointestinal endoscopy to an exciting new level. An update on some of these advances is presented for the physician audience.

EUS-guided drainage of a mediastinal collection complicating FNA of a bronchogenic cyst

EUS has evolved significantly over the last decade, particularly with regard to its therapeutic capabilities. EUS-guided drainage of peripancreatic collections has become the accepted standard of care, with advantages over conventional techniques for non-bulging collections. 1 Furthermore, this technique has been extrapolated successfully for management of a variety of extraluminal collections, with high success rates and few complications. 2-7 We report the first case of EUS-guided drainage of a mediastinal collection that complicated EUS-guided FNA (EUS-FNA) of a bronchogenic cyst.

Single-dose intra-procedural ceftriaxone during endoscopic ultrasound fine-needle aspiration of pancreatic cysts is safe and effective: results from a single tertiary center

Background Endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) is universally used for the investigation and diagnosis of pancreatic cystic lesions (PCL). Infectious complications following EUS-FNA of PCL are rare. Antibiotic prophylaxis to reduce the risk of infection is recommended; however, there is no consensus on the optimal regimen or route of administration. Potential advantages of a single-dose intravenous (IV) antibiotic over a prolonged oral regimen include simplicity, guaranteed delivery and fewer antibiotic related adverse events, but there are only limited data to support this. We aimed to investigate the safety and efficacy of a single 1 g dose of IV ceftriaxone in preventing infectious complications following EUS-FNA of PCL. Methods A retrospective analysis was conducted of EUS-FNA of PCL procedures performed at our center. We reviewed patient medical records for any presentation to a hospital in our district within 30 days of the procedure. An infectious complication was defined as fever/rigors, or bacteremia, or abdominal pain accompanied by imaging or laboratory results suggestive of infection, within 30 days of the procedure. Data collection included patient demographics, procedural data and outcome. Results EUS-FNA of 204 PCL (mean size 18.0 mm) was performed. Successful fluid aspiration was achieved in 94% of cases. Single-dose IV ceftriaxone was given in 146/204 (72%) cases. Four patients had a complication (pancreatitis n=1, post-procedural pain n=3). No infectious complications and no IV antibiotic-related adverse events were identified. Conclusion A single dose of IV ceftriaxone appears to be a safe, effective and convenient intervention for preventing infectious complications after FNA.

Endoscopic ultrasound-fine needle aspiration for the diagnosis of lymphoma: Are we there yet?

In their manuscript published in this issue of the Journal, Al-Haddad and colleagues describe their use of endoscopic ultrasound (EUS) and fine needle aspiration (FNA) with, and in some cases without, flow cytometry in the diagnosis of non-Hodgkin’s lymphoma. Lymph nodes were predominantly intra-abdominal but in some cases mediastinal. The authors present their 7-year experience between 1998 and 2005 outlining the success of this technique in previously undiagnosed lymphoma. Over the past 25 years, there has been a steady increase in the complexity of lymphoma diagnosis based on the availability of techniques beyond tissue pathology; these include flow cytometry, cytogenetics, molecular genetics, fluorescence in situ hybridization and gene array. Despite this, microscopy of tissue sections remains the gold standard in the diagnosis of lymphoma, and excisional biopsy is critical for provision of sufficient tissue for histologic diagnosis and classification, as well as the necessary ancillary tests. Undiagnosed persistently enlarged lymph nodes located in readily accessible areas should without doubt be subjected to excisional biopsy. Lymphadenopathy located in less accessible anatomical locations presents a greater diagnostic challenge, which requires the balancing of diagnostic requirements against the patient’s age and co-morbidities and the type of operative intervention required. Enthusiasm for a minimally-invasive diagnostic tool should not overshadow the need for an accurate diagnosis and classification, as there are important prognostic and treatment implications that differ depending on the lymphoma subtype. Al-Haddad et al. have provided readers with the third and largest series to date examining the utility of EUS-FNA in the diagnosis of lymphoma. They examined 54 patients and detected B-cell lymphomas in 38 patients with reasonable accuracy and with minimal complications. The patient group consisted of those referred with a suspicion of lymphoma. An equally common clinical scenario facing clinicians in every day practice is that of undiagnosed mediastinal or intra-abdominal lymphadenopathy for which a wide variety of differential diagnoses exist; these vary from benign conditions such as sarcoidosis and tuberculosis, to malignant diseases including lymphoma and metastatic carcinoma. The diagnostic utility of EUS-FNA in this broader group of patients has been well demonstrated previously. The results of Al-Haddad et al. provide us with additional confidence that if lymphoma is the cause of the undiagnosed lymphadenopathy, its presence can be reliably detected by EUS-FNA. However, for most patients, this is the start, not the end of the diagnostic process. Most hemato-oncologists would consider additional tissue biopsy (most often excision or core biopsy) still necessary to answer specific prognostic and treatment questions. In a small number of the most elderly or infirm, a decision not to proceed to additional biopsy might be taken in the knowledge that the patient has an unspecified lymphoproliferative disorder rather than an alternative diagnosis such as an epithelial cancer. Perhaps the ‘perfect fit’ for EUS-FNA in the investigation of lymphoma is the confirmation of disease recurrence. In patients with a previously well-characterized lymphoma, tissue architecture is not mandatory for a second-round diagnosis as the classification is already known. In the series of Al-Haddad et al. nine of the 38 patients diagnosed with lymphoma had recurrent disease. This is a nice illustration of the potential role of EUS-FNA with flow cytometry in this subset of patients. Only a small number of lymphoma types provide a sufficiently characteristic cytological, immunophenotypic and/or genetic profile to allow for acceptable diagnosis using fine needle biopsy and flow cytometry alone. Mantle cell lymphoma, a poor prognosis lymphoma of older patients often involving the gastrointestinal tract, is characterized by a variety of morphological lymphoid appearance by cytology, but could be reasonably diagnosed by the presence of cells co-expressing CD5 and CD19 but lacking CD23 expression and simultaneously found to have the bcl-1 mRNA transcript or protein associated with a translocation between chromosomes 11 and 14. Similarly, T cell lymphoblastic lymphoma of the mediastinum could be diagnosed by a fine needle biopsy showing appropriate lymphoid morphology, expression of surface CD2 and staining for cytoplasmic Tdt without the need for more formal biopsy. However, such situations are for now a minority and demand specialist hematology/oncology input regarding diagnostic criteria. In the vast majority of cases, fine needle biopsy of masses suspected of being lymphoma, even when not easily accessible, should be considered an inferior substitute for core or preferably excision biopsy. When fine needle biopsy is done, it should never be performed without accompanying flow cytometry, no matter how confident the attending cytopathologist may be regarding the diagnosis. Al-Haddad et al. performed flow cytometry at the discretion of the endosonographer and cytopathologist when the on-site cytology suggested lymphoma. We would caution against such an approach and suggest that all specimens be sent for flow cytometry when the clinical situation includes lymphoma as a possible differential diagnosis. The use of a trucut core biopsy needle at EUS has previously been examined as a possible solution to the inadequacy of architectural information provided by FNA. These needles (e.g. QuickCore, Cook Medical) can provide tissue fragments as opposed to single cells and cell groups, but require lymph nodes to be of a sufficient size to allow movement of the tray. EUS-guided core biopsy for lymphoma diagnosis has been shown in case reports to improve diagnostic yield above that of FNA alone, but in a series Accepted for publication 11 September 2009.