A Prospective Multicenter Study Evaluating Learning Curves and Competence in Endoscopic Ultrasound and Endoscopic Retrograde Cholangiopancreatography Among Advanced Endoscopy Trainees: The Rapid Assessment of Trainee Endoscopy Skills Study.

BACKGROUND & AIMS: On the basis of the Next Accreditation System, trainee assessment should occur on a continuous basis with individualized feedback. We aimed to validate endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) learning curves among advanced endoscopy trainees (AETs) by using a large national sample of training programs and to develop a centralized database that allows assessment of performance in relation to peers. METHODS: ASGE recognized training programs were invited to participate, and AETs were graded on ERCP and EUS exams by using a validated competency assessment tool that assesses technical and cognitive competence in a continuous fashion. Grading for each skill was done by using a 4-point scoring system, and a comprehensive data collection and reporting system was built to create learning curves by using cumulative sum analysis. Individual results and benchmarking to peers were shared with AETs and trainers quarterly. RESULTS: Of the 62 programs invited, 20 programs and 22 AETs participated in this study. At the end of training, median number of EUS and ERCP performed/AET was 300 (range, 155-650) and 350 (125-500), respectively. Overall, 3786 exams were graded (EUS, 1137; ERCP-biliary, 2280; ERCP-pancreatic, 369). Learning curves for individual end points and overall technical/cognitive aspects in EUS and ERCP demonstrated substantial variability and were successfully shared with all programs. The majority of trainees achieved overall technical (EUS, 82%; ERCP, 60%) and cognitive (EUS, 76%; ERCP, 100%) competence at conclusion of training. CONCLUSIONS: These results demonstrate the feasibility of establishing a centralized database to report individualized learning curves and confirm the substantial variability in time to achieve competence among AETs in EUS and ERCP. ClinicalTrials.gov: NCT02509416.

Severe Elevation of Liver Tests in Choledocholithiasis: An Uncommon Occurrence With Important Clinical Implications.

BACKGROUND AND AIMS: Choledocholithiasis is not commonly associated with dramatic elevations in aminotransferase or total serum bilirubin. Ours is the largest case series thus far studying the prevalence of dramatic elevations in liver tests associated with choledocholithiasis. MATERIALS AND METHODS: We performed a retrospective chart review of all patients with choledocholithiasis diagnosed on endoscopic retrograde pancreatocholangiogram at a tertiary referral hospital over 7 years. We identified 740 patients with available liver tests and determined the prevalence of aspartate aminotransferase (AST)/alanine aminotransferase (ALT) >1000 IU/L and of total serum bilirubin >10 mg/dL. We compared clinical characteristics of these 2 nonoverlapping groups. RESULTS: Of 740 patients, AST and/or ALT values >1000 IU/L were present in 45 (6.1%) patients. On average AST and ALT decreased 79% and 56%, respectively, at discharge 1 to 8 days later. Total serum bilirubin levels >10 mg/dL were present in 35 (4.7%) patients and decreased by an average of 64% at discharge 1 to 8 days later. When compared with the group with total serum bilirubin >10 mg/dL, the group with elevated aminotransferases had significantly more females (93% vs. 43%, P<0.001), had smaller common bile duct diameter (8.5 vs. 10.6 mm, P=0.04), and were more likely to have had a prior cholecystectomy (40% vs. 14%, P=0.01). These 80 patients had higher utilization of health resources: half had additional laboratory studies and one fourth had additional imaging studies performed. CONCLUSIONS: In patients with high AST and/or ALT and serum total bilirubin levels with known choledocholithiasis, elaborate work up to look for another etiology is not required. As long as the values decrease significantly, they do not need to be followed until they normalize in the same hospitalization.

Efficacy of endoscopic ultrasound-guided drainage of pancreatic pseudocysts in a pediatric population.

BACKGROUND: While pancreatitis is uncommon in children, pseudocyst development can be a serious complication. Endoscopic drainage of pseudocysts is well established in adults. However, there are limited data regarding this procedure in a pediatric population. The objective of this study is to determine the safety and efficacy of endoscopic ultrasound-guided pseudocyst drainage in children. METHODS: The study group included children (age <18 years) who presented for endoscopic drainage of symptomatic pancreatic pseudocysts in whom endoscopic ultrasound (EUS) was performed. In those cases with EUS guidance, a 19-gauge needle was used to access the pseudocyst and place a guidewire under fluoroscopic visualization. Needle-knife diathermy and balloon dilation of the tract were performed with subsequent placement of double pig-tailed stents for drainage. RESULTS: Ten children with mean age of 11.8 years (range 4-17 years) were analyzed for pancreatic pseudocysts due to biliary pancreatitis (n = 4), trauma (n = 2), familial pancreatitis (n = 1), idiopathic pancreatitis (n = 2), and pancreas divisum (n = 1). In eight cases, EUS-guided puncture and stent placement was successful. In the remaining two cases, aspiration of cyst fluid until complete collapse was adequate. As experience increased with EUS examination in children, the therapeutic EUS scope alone was used in 50% of cases for the entire procedure. In all ten cases, successful transgastric endoscopic drainage of pseudocysts was achieved. CONCLUSIONS: Endoscopic drainage of symptomatic pancreatic pseudocysts can be achieved safely in children. EUS guidance facilitates optimal site of puncture as well as placement of transmural stents.

The clinical utility and limitations of serum carbohydrate antigen (CA19-9) as a diagnostic tool for pancreatic cancer and cholangiocarcinoma.

BACKGROUND: CA19-9 is a tumor marker for pancreatic cancer, cholangiocarcinoma, and other malignancies. However, its sensitivity and specificity is suboptimal in clinical practice, which we hypothesized limits its clinical utility. AIMS: To evaluate the clinical utility and limitations of CA19-9 as a tumor marker. METHODS: We performed a retrospective review of CA19-9 levels (U/ml) in 483 consecutive patients between 2006 and 2008 at two university hospitals. We abstracted clinical, radiographic, and pathological data and final diagnoses. Descriptive and non-parametric analyses were performed. RESULTS: Patients presenting with jaundice had the highest CA19-9 (420) compared to other complaints (<20) (p<0.01). The indications with the highest CA19-9 had evidence of biliary obstruction (71), liver mass (54), and pancreatic head mass (27) compared to other indications (<15) (p<0.01). The diagnoses with the highest CA19-9 (p<0.01) were cholangiocarcinoma (476), pancreatic cancer (161), and choledocholithiasis (138). Using a receiver operator curve to evaluate CA19-9, the area under the curve was 0.7 when evaluating all patients for pancreatic cancer or cholangiocarcinoma or patients with pancreatic head mass for pancreatic cancer. CONCLUSIONS: This study found that for pancreatic cancer and cholangiocarcinoma, CA19-9 had poor clinical utility as a tumor marker and did not change patient management. Elevations in CA19-9 were associated with biliary obstruction based on clinical history, laboratory data, and diagnoses.

Endoscopic ultrasound-guided transduodenal placement of a fully covered metal stent for palliative biliary drainage in patients with malignant biliary obstruction.

BACKGROUND: Endoscopic ultrasound (EUS)-guided biliary drainage (EUSBD) has been described as a viable alternative to percutaneous transhepatic cholangiography (PTC) in patients in whom ERCP has been unsuccessful. The purpose of our study was to assess the utility of EUSBD using a newly released, fully covered, self-expanding, biliary metal stent (SEMS) for palliation in patients with an obstructing malignant biliary stricture. METHODS: We collected data on all patients who presented with obstructive jaundice and who underwent transduodenal EUSBD after a failed ERCP. Eight patients presented with biliary obstruction from inoperable pancreatic cancer or cholangiocarcinoma. Reasons for failed ERCP were duodenum stenosis, high-grade malignant stenosis of the common bile duct, periampullary tumor infiltration, failure to access the common bile duct, and periampullary diverticulum. EUS was used to access the common bile duct from the duodenum after which a guidewire was advanced upwards toward the liver hilum. The metal stent was then advanced into the biliary tree. Technical success was defined as correct stent deployment across the duodenum. Clinical success was defined as serum bilirubin level decreased by 50% or more within 2 weeks after the stent placement. RESULTS: Technical and clinical success was achieved in all eight patients. No stent malfunction or occlusion was observed. Complications included one case of duodenal perforation, which required surgery, and one case of self-limiting abdominal pain. CONCLUSIONS: EUSBD with a fully covered SEMS in whom ERCP is unsuccessful is effective for palliation of biliary obstruction. The limitations of our study are that we had a small number of patients and a limited follow-up time.

Acute pancreatitis during pregnancy.

BACKGROUND & AIMS: Acute pancreatitis is rare during pregnancy; limited data are available about maternal and fetal outcomes. We investigated the effects of acute pancreatitis during pregnancy on fetal outcome. METHODS: This retrospective cohort study, performed at a single academic center, included consecutive pregnant women who presented with (n = 96) or developed acute pancreatitis in the hospital (n = 7) in 2000-2006 (mean age, 26 y). Patient histories and clinical data were collected from medical records. RESULTS: Of the 96 patients with spontaneous pancreatitis, 4 had complications: 1 patient in the first trimester had acute peripancreatic fluid collection, and 3 patients in the third trimester developed disseminated vascular coagulation (DIC). None of these patients achieved term pregnancy, and 1 of the patients with DIC died. Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 23 patients with acute pancreatitis; post-ERCP pancreatitis was diagnosed in 4 patients (a total of 11 patients developed ERCP-associated pancreatitis). Term pregnancy was achieved in 73 patients (80.2%). Patients who developed pancreatitis in the first trimester had the lowest percentage of term pregnancy (60%) and highest risks of fetal loss (20%) and preterm delivery (16%). Of the patients with pancreatitis in the second and third trimesters, only one had fetal loss. Fetal malformations were not observed. CONCLUSIONS: The majority of pregnant patients with acute pancreatitis did not have complications; most adverse fetal outcomes (fetal loss and preterm delivery) occurred during the first trimester. Acute pancreatitis, complicated by DIC, occurred most frequently in the third trimester and was associated with poor fetal and maternal outcomes.

A comparison of palliative stenting or emergent surgery for obstructing incurable colon cancer.

BACKGROUND: Acute colonic obstruction because of advanced colonic malignancy is a surgical emergency. Our aim was to review our experience with self-expanding metal stents (SEMS) compared to emergent surgery as the initial therapy for the management of patients with incurable obstructing colon cancer. METHODS: A retrospective review of patients with obstructing colon cancer who underwent insertion of a SEMS (n = 53) or surgery (n = 70) from 2002 to 2008 was performed. The primary endpoint was relief of obstruction. Secondary endpoints include technical success of the procedure, duration of hospital stay, early and long-term complications, and overall survival. RESULTS: Both groups were similar in age, sex, and tumor distribution. Placement of SEMS was successful in 50/53 (94%) patients. Surgery was effective in relieving obstruction in 70/70 (100%) patients. Patients in the SEMS group have a significantly shorter median hospital stay (2 days) as compared to the surgery group (8 days) (P < 0.001). Patients with SEMS also had significantly less acute complications compared to the surgery group (8 vs. 30%, P = 0.03). The hospital mortality for the SEMS group was 0% compared to 8.5% in patients that underwent surgical decompression (P = 0.04). There was no difference in survival between the two groups (P = 0.76). CONCLUSIONS: In patients with colorectal cancer and obstructive symptoms, SEMS provide a highly effective and safe therapy when compared to surgery. In most patients with metastatic colorectal cancer and obstruction, SEMS provide a minimally invasive alternative to surgical intervention.

Dieulafoy lesions of the GI tract: localization and therapeutic outcomes.

OBJECTIVES: Dieulafoy lesions are a rare cause of gastrointestinal hemorrhage with a striking presentation because of rapid blood loss. Endoscopic therapy is usually successful at achieving primary hemostasis, but the best mode of endoscopic intervention is not clear, and outcomes relating to variables such as gender, medication, alcohol, and smoking are not known. We reviewed the clinical experience with Dieulafoy lesions at our institution, focusing on clinico-epidemiological features, management practices, and also survival. METHODS: A retrospective and prospective cohort of patients with Dieulafoy lesions who underwent endoscopy from January 2004 through April 2009 were studied and detailed clinical data were abstracted and collected. RESULTS: We identified 63 patients with a Dieulafoy lesion. The majority were male with an average age 58 years. Hematemesis and melena were the most common presenting symptoms. Almost half the patients were on anticoagulation medication. Most of the Dieulafoy lesions occurred in the upper GI tract, and mostly in the stomach. Single-modality endoscopic therapy was used as frequently as combination therapy, and both were effective, as primary hemostasis was achieved in 92% of cases. There were 11 deaths overall; death due to Dieulafoy lesion exsanguination was attributed to three patients. CONCLUSIONS: Dieulafoy lesions occurred in younger patients than previously reported, and were more frequently diagnosed in males. Most DL lesions occurred in the upper GI tract. Primary hemostasis with endoscopic therapy was highly successful. Overall mortality was 17%, and associated with co-morbidities, and not with medical history, gender, age, or medication.

Safety and utility of ERCP during pregnancy.

BACKGROUND: ERCP is an important diagnostic and therapeutic tool in patients with biliary and pancreatic disease. Its utility and safety during pregnancy is largely unknown because it is not often required and because its use has been only infrequently reported in the published literature. OBJECTIVE: Our purpose was to report the clinical experience with ERCP during pregnancy. DESIGN: Retrospective review, single academic center. PATIENTS: All (consecutive) pregnant women who underwent ERCP at Parkland Memorial Hospital from 2000 to 2006. MAIN OUTCOME MEASUREMENTS: History, clinical data, hospital course, procedure-related complication rates and outcomes, and delivery and fetal outcomes were abstracted from medical records. RESULTS: During the study period, 68 ERCPs were performed on 65 pregnant women. The calculated ERCP rate was 1 per 1415 births. The common indications for ERCP in pregnancy were recurrent biliary colic, abnormal liver function tests, and dilated bile duct on US. ERCP was technically successful in all patients. The median fluoroscopy time was 1.45 minutes (range 0-7.2 minutes). There was no perforation, sedation-related adverse event, postsphincterotomy bleeding, cholangitis, or procedure-related maternal or fetal deaths. Post-ERCP pancreatitis was diagnosed in 11 patients (16%). None of these 11 patients had local or systemic complications. Fifty-nine patients had complete follow-up. Endoscopic therapy at the time of ERCP was undertaken in all patients. Furthermore, 9 patients (32.1%) underwent cholecystectomy in the first and second trimesters for either acute cholecystitis (6) or symptomatic gallstones (3). Term pregnancy was achieved in 53 patients (89.8%). Patients having ERCP in the first trimester had the lowest percentage of term pregnancy (73.3%) and the highest risk of preterm delivery (20.0%) and low-birth-weight newborns (21.4%). None of the 59 patients with long-term follow-up had spontaneous fetal loss, perinatal death, stillbirth, or fetal malformation. LIMITATION: Retrospective review. CONCLUSIONS: ERCP can be performed safely during pregnancy. Further, ERCP performed in pregnancy leads to specific therapy in essentially all patients. However, ERCP may be associated with a higher rate of post-ERCP pancreatitis than in the general population.

Endoscopic hemostasis in nonvariceal upper gastrointestinal bleeding: comparison of physician practice in the East and the West.

BACKGROUND: Endoscopic hemostasis is commonly practiced during GI endoscopy practice. We hypothesized that, because the choice of endoscopic intervention is influenced by many factors, for example personal experience, prior training, guidelines, etc., there would be differences in practice patterns among different groups of endoscopists. OBJECTIVE: To explore the potentially different practices for endoscopic hemostasis between the "East" (eight Asian countries) and the "West" (USA and Canada). DESIGN: Cross-sectional descriptive study (internet-based survey). STUDY SUBJECTS: We administered a questionnaire survey to American Society of Gastrointestinal Endoscopy (ASGE) and Korean Society of Gastroenterology (KSGE) members (see: http://www4.utsouthwestern.edu/inetdemo/endoscopy/hemostasis.html , or supplementary paper for review online). RESULTS: Eastern ASGE members (n = 112) were more likely to complete this survey than ASGE members in the West (n = 180): 15.1 vs. 5.0%, P < 0.001. Choice of hemostatic method, regardless of primary or recurrent bleeding, varied significantly among Eastern and Western endoscopists. For example, for treatment of a gastric ulcer with a visible vessel, a vast majority (70%) of Western endoscopists preferred pre-injection followed by thermocoagulation whereas responses from the East were more diverse, with endoclip application +/- pre-injection being the top choice (29%) (P < 0.001). Personal EGD volume and hospital bed numbers did not seem to be associated with hemostatic choices in either the East or the West. CONCLUSIONS: Endoscopic hemostasis practice patterns for upper GI tract bleeding differed among Eastern and Western endoscopists, suggesting fundamental differences in practice habit determinants.

A comparative analysis of pancreas cyst fluid CEA and histology with DNA mutational analysis in the detection of mucin producing or malignant cysts.

CONTEXT: The main objective of pancreatic cyst fluid analysis is to differentiate mucin-producing or malignant cysts from other cysts which have a benign course. K-ras-2 point mutation and at least two mutations of allelic imbalance or loss of heterozygosity with good quality DNA has been suggested to predict mucinous cystic neoplasm (MCN). Elevated carcinogenic embryonic antigen (CEA) level in cyst fluid has also been shown to be predictive of mucinous or malignant cysts. OBJECTIVE: Identify the clinical impact of DNA mutational analysis of pancreatic cyst fluid with its correlation to cyst fluid chemistry and histologic analysis. PATIENTS: This retrospective analysis included all consecutive patients with pancreatic cysts who presented for evaluation by endoscopic ultrasound (EUS) with fine needle aspiration (FNA) over an 18 month period until November 2007. MAIN OUTCOME MEASURES: DNA analysis performed by Pathfinder TG (RedPath Integrated Pathology, Inc., Pittsburgh, PA, USA) and fluid CEA exceeding 192 ng/dL were used to suggest mucinous or malignant cysts. These parameters were compared to surgical histology or cytopathology of FNA specimens. RESULTS: Twenty-seven consecutive patients with cysts had samples submitted for DNA analysis which included 15 men and 12 women (mean age 62.8 and 61.3 years, respectively). In 20 patients, all parameters including cyst fluid, DNA analysis, and histology were available for comparison. Consistent findings were seen in 7/20 (35%) in which all parameters suggested negative benign findings. CEA level was elevated in 7 patients of which 4 had mucinous or malignant histology. In the remaining 13 patients with low CEA levels, 11 had negative histology. The sensitivity and specificity of CEA based on these results was 66% and 78.6% respectively. The positive predictive value (PPV) of CEA was 57% and the negative predictive value (NPV) was 84.6%. K-ras-2 mutation was detected in 3 patients, absent in 17 patients and falsely negative in 4 cases based on histology. The sensitivity and specificity were 33% and 92.6% respectively. The PPV was 66% and NPV was 76%. Detection of loss of heterozygosity mutations was noted in 7 patients, of which 4 were falsely positive. In the remaining 13 patients, 3 were falsely negative. The sensitivity and specificity were 50% and 71% respectively. The PPV was 42.9% and NPV was 76.9%. In a group of 6 patients with available surgical histology demonstrating mucin-producing or malignant cysts, fluid CEA level had a sensitivity of 66.7%. However, K-ras-2 and loss of heterozygosity mutational analysis had a much lower sensitivity at 33% and 50% respectively. CONCLUSIONS: Consistency in histology, CEA levels, and K-ras-2 and loss of heterozygosity mutations was seen in only 35% of cases, all of which were benign cysts. In the detection of malignant cysts, elevated CEA levels were more predictive of histology in comparison to K-ras-2 or loss of heterozygosity mutations. Additionally, false positivity of loss of heterozygosity mutations was noted to be considerably higher than K-ras-2 mutations or even fluid CEA levels. These findings suggest that DNA mutation analysis should not be used routinely but rather selectively in the evaluation of pancreatic cysts.

Managing anticoagulation and antiplatelet medications in GI endoscopy: a survey comparing the East and the West.

BACKGROUND: Anticoagulation and antiplatelet medications may potentiate GI bleeding, and their use may lead to an increased need for a GI endoscopy. We hypothesized that there might be different practice patterns among international endoscopists. OBJECTIVE: To explore the differences in management practices for patients who receive anticoagulation and antiplatelet medications from Eastern and Western endoscopists. DESIGN: International survey study. SETTING: Academic medical centers and private clinics. SUBJECTS: Members of the American Society for Gastrointestinal Endoscopy (ASGE) in Eastern (Korea, Japan, China, India, Thailand, Singapore, Malaysia, and Philippines) and Western (United States and Canada) countries were invited to complete a Web-site-based questionnaire. In addition, the questionnaire was sent to university hospitals in South Korea and academic institutions in the United States. METHODS: A survey was administered that contained detailed questions about the use of an endoscopy in patients on anticoagulation and antiplatelet medications. MAIN OUTCOME MEASUREMENTS: Different opinions and clinical practice patterns regarding the use of anticoagulation and antiplatelet medications by Eastern and Western endoscopists. RESULTS: A total of 105 Eastern and 106 Western endoscopists completed the survey. Western endoscopists experienced more instances of procedure-related bleeding (P = .003) and thromboembolism after withdrawal of medications (P = .016). Eastern endoscopists restarted medications later (1-3 days) than Western endoscopists after a biopsy (same day) (P < .001). Eastern endoscopists withdrew aspirin for more than 7 days before a polypectomy and then restarted it 1 to 3 days after a polypectomy, whereas Western endoscopists performed a polypectomy without withdrawing aspirin (P < .001). ASGE guidelines were followed less often by Eastern than by Western endoscopists (P < .001). LIMITATIONS: Low response rate, heterogeneity of the sample, and recall bias. CONCLUSIONS: The opinions and clinical practice patterns for the management of anticoagulation and antiplatelet medications differed significantly between Eastern and Western endoscopists. The lack of uniformity in practice patterns suggests that more data and better education are required in the area of GI endoscopy for patients on anticoagulation and antiplatelet medications, particularly given that individual patient characteristics may be associated with unique types of complications.

Endoscopic hemostasis using endoclip in early gastrointestinal hemorrhage after gastric bypass surgery.

Roux-en-Y gastric bypass (RYGBP) is the most commonly performed bariatric operation in the USA. In the early postoperative stage, gastrointestinal (GI) bleeding is an infrequent but potentially serious complication that usually results from bleeding at the gastrojejunostomy staple-line. Observant management with transfusion for stable patients and surgical exploration for unstable patients is typically recommended for early GI bleeding. We hypothesized that use of endoclips, which do not cause thermal injury to the surrounding tissues (or anastomosis), may be preferable to thermal approaches which could cause tissue injury. We report 2 cases of early GI bleeding after RYGBP that were successfully managed with endoclip application to bleeding lesions. Emergent endoscopy was performed, and major stigmata such as active spurting vessel and adherent clot were noted at the gastrojejunostomy staple-lines. Endoscopic hemostasis using endoclips was readily applied to bleeding lesions at staple-lines. Primary hemostasis was achieved, and there was no recurrent bleeding or complication. We conclude that therapeutic endoscopy can be performed safely for early bleeding after RYGBP. In patients with early bleeding after RYGBP, use of endoclips is mechanistically preferable to other options.

Can clinical factors predict the need for intervention after a positive intraoperative cholangiogram?

OBJECTIVE: To determine whether clinical factors such as the elevation or decline of biochemical liver tests and bile duct dilation can help to identify patients who will truly benefit from therapeutic endoscopic retrograde cholangiopancreatography (ERCP) following a positive intraoperative cholangiography (IOC) study. METHODS: All cholecystectomies during a 3-year period were examined retrospectively for positive intraoperative cholangiograms. Sonographic findings of bile duct dilation and transaminase levels at admission, including trends during the course of hospitalization and prior to ERCP, were evaluated. RESULTS: Of 369 patients with intraoperative cholangiogram studies, 80 (21.7%) were positive. Prior to surgery, a sonogram showed biliary dilation in 50 (62.5%) and ERCP demonstrated actual stones in 27 (61.4%) out of 44 patients. In 24 patients with persistent elevation in transaminases and no biliary dilation, ERCP revealed stones in 12 (50.0%). Sonographic finding of biliary dilation had a positive predictive value (PPV) of 61.4% and a negative predictive value (NPV) of 60.0%. Persistent elevation in transaminases had a PPV of 59.3%. A 50% decline in transaminases had a NPV of 41.2%. Overall, only 39 (48.8%) of all patients with a positive intraoperative cholangiogram study required therapeutic ERCP. CONCLUSIONS: Elevated transaminases and sonographic biliary dilation have poor predictive values for choledocholithiasis. Thus, patients with a positive intraoperative cholangiogram may benefit from additional studies, such as endoscopic ultrasound or magnetic resonance cholangiopancreatography prior to ERCP.

Endoscopic applications of cryospray ablation therapy-from Barrett's esophagus and beyond.

In the last decade, the treatment of dysplastic Barrett's esophagus has evolved into primarily endoscopic therapy. Many techniques have become well-established to destroy or remove the mucosal lining of Barrett's esophagus. One of the newest therapies, cryospray ablation, has become a modality to treat both dysplastic Barrett's esophagus as well as esophageal carcinoma. In endoscopic applications, the cryogen used is either liquid nitrogen or carbon dioxide which causes tissue destruction through rapid freeze-thaw cycles. Unlike other endoscopic ablation techniques, its unique mechanism of action and depth of tissue injury allow cryoablation to be used effectively in flat or nodular disease. It can be combined with other modalities such as endoscopic mucosal resection or radiofrequency ablation. Its esophageal applications stem well-beyond Barrett's into ablation of early carcinoma, palliative debulking of advanced carcinoma and reduction of tumor ingrowth into stents placed for dysphagia. Although there are fewer reported studies of endoscopic cryoablation in the literature compared to other endoscopic ablation methods, emerging research continues to demonstrate its efficacy as a durable ablation technology with a variety of applications. The aim of this review is to examine the pathophysiology of endoscopic cryospray ablation, describe its outcomes in Barrett's with dysplasia and esophageal carcinoma, and examine its role in other gastrointestinal applications such as hemostasis in the stomach and rectum.

Chronic mesenteric ischemia.

Chronic mesenteric ischemia is an unusual but important cause of abdominal pain. Although this condition accounts for only 5% of all intestinal ischemic events, it can have significant clinical consequences. Among its many causes, atherosclerotic occlusion or severe stenosis is the most common. This disorder has an indolent course that results in extensive collateral vascular formation. Thus, symptoms occur when at least two of the three main splanchnic vessels are affected. Intestinal angina, weight loss, and sitophobia are common clinical features. Diagnosis can often be made by noninvasive methods such as computerised axial tomographic angiography, magnetic resonance angiography, and duplex ultrasonography as well as by invasive catheter angiography. Therapy of chronic mesenteric ischemia depends on the extent and location of vascular disease. Alternatives to traditional surgical bypass are becoming more common including embolectomy, thrombolysis, and percutaneous angioplasty with vascular stenting. Early intervention is vital as the natural course of this illness can be debilitating. Furthermore, this has potential to develop into life-threatening acute mesenteric ischemia with subsequent bowel infarction and death. Long-term studies have shown that the risk of developing symptoms from asymptomatic but significant mesenteric vascular disease is 86% with overall 40% mortality rate. The recognition and management of this unusual but important cause of abdominal pain is discussed in detail in this review.

The emerging role of endoscopic ultrasonography in cancer staging.

The management of solid organ cancers relies on accurate staging. Once distal metastasis has been excluded by conventional radiographic methods, local staging of the tumor and its nodal involvement is essential to determine the most optimal therapeutic approach. Many radiographic imaging modalities are unable to determine subtle tumor involvement. However, the emergence of endoscopic ultrasonography (EUS) has given promise to improved staging with its unique ability to examine tumors from within the gastrointestinal lumen with extremely close proximity. An additional advantage is the ability to perform fine-needle aspiration (FNA) biopsy to confirm or exclude tumor involvement. Many studies have shown superior accuracy in staging with EUS and EUS-FNA for tumors of the esophagus, stomach, pancreas, rectum, and mediastinum, including lung cancer. This review illustrates the principles of EUS and its role in staging of a variety of cancers and particularly its role alongside other imaging modalities.