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Enrique Vazquez-Sequeiros

Publications and source records attributed to Enrique Vazquez-Sequeiros.

16 recordsLinked to original sources
PubMed2006

Routine vs. selective EUS-guided FNA approach for preoperative nodal staging of esophageal carcinoma.

BACKGROUND: EUS-guided FNA (EUS-FNA) is the most accurate method for lymph-node staging of esophageal carcinoma; however, it may not be necessary when EUS features are present that strongly suggest a benign or a malignant origin. AIMS: (1) To identify a combination of EUS criteria that have a sufficient sensitivity and specificity to preclude the need for EUS-FNA and (2) to assess the cost savings derived from a selective EUS-FNA approach. METHODS: A total of 144 patients with esophageal carcinoma were prospectively evaluated with EUS. Accuracy of standard (hypoechoic, smooth border, round, or width > 5 mm) and modified (4 standard plus EUS identified celiac lymph nodes, >5 lymph nodes, or EUS T3/4 tumor) criteria were compared (receiver operating characteristic curves). Resource utilization of two diagnostic strategies, routine (all patients with lymph nodes) and selective EUS-FNA (FNA only in those patients in whom the number of EUS malignant criteria provides a sensitivity and a specificity <100%), were compared. RESULTS: Modified EUS criteria for lymph-node staging were more accurate than standard criteria (area under the curve 0.88 vs. 0.78, respectively). No criterion alone was predictive of malignancy; sensitivity and specificity reached 100% when a cutoff value of >1 and >6 modified criteria were used, respectively. The EUS-FNA selective approach may avoid performing FNA in 61 patients (42%). CONCLUSIONS: Modified EUS lymph-node criteria are more accurate than standard criteria. A selective EUS-FNA approach reduced the cost by avoiding EUS-FNA in 42% of patients with esophageal carcinoma. These results require confirmation in future studies.

Adult↗
PubMed2005

Age-related changes in the pancreas identified by EUS: a prospective evaluation.

BACKGROUND: EUS is an important modality for the diagnosis of pancreatic disease. An understanding of normal pancreatic ductal and parenchymal variation in asymptomatic individuals is essential to improve EUS accuracy. The primary aim of this study was to determine age-related pancreatic parenchymal and ductular changes identifiable on EUS in individuals with no history or symptoms of pancreaticobiliary disease. Secondary aims were to define demographic and clinical factors associated with identifiable pancreatic parenchymal and ductular changes, and to determine the main pancreatic-duct diameter and pancreatic-gland width according to age. METHODS: Patients referred for either upper endoscopy or EUS for an indication unrelated to pancreaticobiliary disease were prospectively enrolled. Patients were stratified by age (<40, 40-60, >60 years). Each patient was assessed for the presence of EUS findings for chronic pancreatitis. Logistic regression was used to identify factors associated with an abnormality. RESULTS: A total of 120 patients (63 men, 57 women; median age, 52 years, interquartile range [IQR] 40-61 years) were prospectively evaluated. At least one parenchymal and/or ductular abnormality was identified in 28% of the patients, with a trend of increasing abnormality with age: <40 years (23%), 40 to 60 years (25%), and >60 years (39%); p = 0.13. No patient had more than 3 abnormal EUS features. Hyperechoic stranding (n = 22) was the most common finding in all age groups. The odds for any abnormality in men (relative to women) was significantly higher (OR 2.9: 95% CI[1.2, 6.8], p = 0.01), with 38% of men and 18% of women having an abnormality. Smoking, low alcohol intake, body mass index, and endoscopic finding were not significantly associated with an abnormal EUS. The overall median pancreatic-gland width and main pancreatic duct diameter were 15 mm (IQR 6-25 mm) and 1.7 mm (IQR 0.9-4.3 mm), respectively. CONCLUSIONS: The frequency of EUS abnormalities in patients without clinical evidence of chronic pancreatitis increases with age, particularly after 60 years of age. The threshold number of EUS criteria for the diagnosis of chronic pancreatitis is variable. However, the typically used standard of 3 or more criteria appears appropriate. A higher number of threshold criteria may be needed in males and to a lesser extent in patients over 40 years of age, which should be related to clinical history and other structural or functional studies. Ductal or parenchymal calculi, ductal narrowing, ductal dilatation, or more than 3 abnormalities appear to be more specific features for the EUS diagnosis of chronic pancreatitis at any age.

Adult↗
PubMed2003

Impact of lymph node staging on therapy of esophageal carcinoma.

BACKGROUND & AIMS: Therapy of esophageal carcinoma is stage dependent. The role of EUS-guided fine-needle aspiration (EUS FNA) in this setting is unclear. The aims of this study were to compare the performance characteristics of CT, EUS, and EUS FNA for preoperative nodal staging of esophageal carcinoma and to measure the impact of each staging test on treatment decisions. METHODS: From December 1999 to March 2001, all patients with esophageal carcinoma seen at the Mayo Clinic Rochester were prospectively evaluated with CT, EUS, and EUS FNA. The impact of tumor stage on final therapy was assessed. RESULTS: A total of 125 patients with esophageal carcinoma were enrolled. EUS FNA was more sensitive (83% vs. 29%; P < 0.001) than CT and more accurate than CT (87% vs. 51%; P < 0.001) or EUS (87% vs. 74%; P = 0.012) for nodal staging. Direct surgical resection was contraindicated in 77% of patients evaluated due to advanced locoregional/metastatic disease. Tumor location, patient age, comorbidities, and tumor stage determined by CT, EUS, and EUS FNA were associated with treatment decisions (P < 0.05). EUS FNA resulting in a higher/worse stage than CT (41 patients) was associated with a greater rate of treatments that were not direct surgeries compared with cases in which the stage was the same or better. CONCLUSIONS: EUS FNA is more accurate for nodal staging and impacts on therapy of patients with esophageal carcinoma. EUS FNA should be included in the preoperative staging algorithm of these patients.

Adult↗
PubMed2003

A simple phantom for learning EUS-guided FNA.

BACKGROUND: The learning curve for EUS-guided FNA (EUS-FNA) is formidable. Development of a phantom to assist in teaching the technique may be beneficial. This study assessed the feasibility of using a low-cost phantom made of commonly available materials to practice EUS-FNA. METHODS: A 2500-mL barium enema bag was modified by running a plastic tube (3-mm inner diameter) through it and sealing one end. One hundred grams of standard agar were suspended in 4 liters of tap water. The broth was heated slowly to boiling. The dissolved agar was then transferred to the barium enema bag after mixing in diced carrots, elbow macaroni, peas, and fingertips of surgical gloves filled with 5 mL of normal saline solution (6 of each) to simulate solid and cystic lesions. Immersion of the phantom in a basin of water provided acoustic coupling. One end of the 3-mm plastic tubing was attached to the nozzle of a water jet device and the other end to its reservoir to create a closed system allowing water recirculation. A linear array echoendoscope and a fine needle were used to perform EUS-FNA. The analysis is descriptive. OBSERVATIONS: The phantom was readily made with inexpensive components (total cost <$50). With refrigeration the phantom was used repetitively during a 4-month period. It produced EUS images with an echotexture comparable with liver. The solid and cystic components resembled hepatic cysts and solid masses encountered when performing EUS in humans. Under EUS-guidance, fine-needle aspirates of selected lesions could be performed allowing targeting, aspiration, and sampling of selected lesions. The Doppler flow effect allowed examination of a simulated vascular structure during FNA. CONCLUSIONS: Once validated, an EUS phantom made of simple components may become an invaluable educational tool for teaching EUS-FNA. Further studies are needed to determine how it affects the skills of gastroenterologists with and without EUS experience.

Biopsy, Needle↗
PubMed2003

Prospective risk assessment of bacteremia and other infectious complications in patients undergoing EUS-guided FNA.

BACKGROUND: There are few data regarding the risk of bacteremia with EUS-guided FNA. This study prospectively evaluated the frequency of bacteremia and other infectious complications after EUS-guided FNA. METHODS: Patients referred for EUS-guided FNA of the upper GI tract lesions were considered for enrollment. Patients were excluded if there was an indication for preprocedure administration of antibiotics based on ASGE guidelines, had taken antibiotics within the prior 7 days, or if they had a pancreatic cystic lesion. Blood cultures were obtained immediately before the procedure, after routine endoscopy/radial EUS, and 15 minutes after EUS-guided FNA. RESULTS: Fifty-two patients underwent EUS-guided FNA at 74 sites (mean 1.4 sites/patient) totaling 266 passes of the fine needle (mean 5.1 FNA/patient). Coagulase negative Staphylococcus was grown in cultures from 3 patients (5.8%; 95% CI [1%, 15%]) and was considered a contaminant. Three patients (5.8%; 95% CI [1%, 15%]) developed bacteremia: Streptococcus viridans (n = 2), unidentified gram-negative bacillus (n = 1). No signs or symptoms of infection developed in any patient. CONCLUSION: EUS-guided FNA of solid lesions in the upper GI tract should be considered a low-risk procedure for infectious complications that does not warrant prophylactic administration of antibiotics for prevention of bacterial endocarditis.

Adult↗
PubMed2002

Use of a phased vector array US catheter for EUS.

BACKGROUND: Existing EUS catheter probes have limited depth of penetration and lack color flow and Doppler capabilities. This study prospectively assessed the feasibility and safety of using a phased vector array US catheter in the human GI tract. METHODS: Eleven patients underwent EUS with a steerable 9F phased vector array catheter. Images obtained with the catheter were compared with standard EUS images. RESULTS: The GI wall layers were equally well imaged with the catheter compared with standard echoendoscopes in 90% of the cases. Images of the liver, spleen, pancreatic parenchyma, and pancreatic duct were of equal quality and resolution with both techniques in the majority of patients. Some deeper structures and blood vessels were better visualized with the catheter. No complications were encountered. CONCLUSION: The steerable phased vector array US catheter is a safe device when used in the GI tract and offers images comparable with those obtained with a dedicated echoendoscope. Further studies are needed to determine the accuracy of tumor staging and clinical utility of this device.

Adult↗
PubMed2002

Initial experience with EUS-guided trucut needle biopsies of perigastric organs.

BACKGROUND: The aims of this study were to determine the feasibility, safety, and yield of a 19-gauge EUS-guided-trucut needle for obtaining biopsy specimens of perigastric organs. METHODS: The study was performed in swine under general anesthesia. EUS-guided trucut needle biopsy specimens were obtained from the spleen, liver, pancreas body, and left kidney. Biopsy specimens were assessed for size, fragmentation, and representation of the target organ. OBSERVATIONS: Twenty-eight biopsy specimens were obtained from the 4 target organs with two needles. Median biopsy length was 6 mm (spleen), 4 mm (liver), 6 mm (left kidney), and 2 mm (pancreas body). Of all the specimens, 75% to 100% had tissue representative of the target organ. EUS visualization of the needle was excellent and no complications were identified. CONCLUSIONS: Use of the trucut needle under EUS guidance to obtain biopsy specimens of perigastric organs appears safe and yields specimens that are representative of the target organ sampled. Further study of the utility and safety of this needle in humans is warranted.

Animals↗
PubMed2002

Usefulness of EUS-guided fine needle aspiration (EUS-FNA) in the diagnosis of functioning neuroendocrine tumors.

BACKGROUND: Localization of neuroendocrine tumors may be challenging. The role of EUS-FNA in this setting is unknown. METHODS: Ten patients with clinically suspected functioning neuroendocrine tumors (hormonal disturbances) underwent EUS-FNA to determine the location and to confirm the diagnosis cytologically. OBSERVATIONS: EUS identified 14 tumors in these 10 patients. In all but one patient CT did not demonstrate the tumor or missed at least one of multiple lesions. Mean tumor size was 12 mm (range 4-25 mm). Tumor locations were pancreas (n = 13) and duodenal wall (n = 1). Eleven of the 14 detected lesions were aspirated under EUS with accurate diagnosis in all cases. Surgical confirmation of EUS-FNA findings was available in 7 patients. There was no complication of EUS-FNA. CONCLUSIONS: EUS is a highly accurate technique for visualization of small functioning neuroendocrine tumors not evident on CT and for identification of patients with multiple lesions. EUS-FNA safely provides cytologic confirmation with high accuracy in these patients.

Adult↗
PubMed2002

Occult lymph node metastases as a predictor of tumor relapse in patients with node-negative esophageal carcinoma.

BACKGROUND & AIMS: Esophageal carcinoma is an aggressive disease with a very poor prognosis. Early tumor relapse after surgical resection in patients with node-negative esophageal carcinoma suggests that occult metastases may have been missed at the original pathologic examination. The aim of this study was to determine the prevalence of immunohistochemically detected occult lymph node microscopic metastases in patients with pathologic N0 esophageal carcinoma and the impact of these occult metastases on relapse-free survival. METHODS: All patients (n = 124) with pathologic N0 esophageal carcinoma undergoing resection at our institution between January, 1994, and October, 1998, constituted the study population. Esophagectomy specimens were reevaluated by immunohistochemistry (monoclonal antibody against cytokeratin AE1/AE3). Clinical and pathologic features were summarized, and patient relapse-free survival was estimated. RESULTS: Among the total of 124 patients, occult lymph node microscopic metastases were identified by immunohistochemistry in 14 patients (11%) (T1 mucosa, 4%; T1 submucosa, 6%; T2, 22%; and T3, 14%). Patients were followed for a median of 3.2 years. Relapse-free survival was not significantly associated with the presence of occult lymph node microscopic metastases as detected by immunohistochemistry (P = 0.12). Advanced T stage (T3; P < 0.001) and lymphovascular invasion (P < 0.001) were found to be associated with tumor relapse. CONCLUSIONS: In the present study, occult lymph node microscopic metastases in pathologic N0 esophageal carcinoma patients were less frequent than previously reported. T stage and lymphovascular invasion were significantly associated with relapse-free survival, although a significant association with occult lymph node metastases was not detected.

Blood Vessels↗
PubMed2002

High-frequency US catheter-based staging of early esophageal tumors.

BACKGROUND: High-frequency catheter US probes provide greater accuracy compared with dedicated echoendoscopes in the staging of superficial esophageal carcinoma. However, it may be difficult and time consuming to obtain acoustic coupling with these devices. The aim of this study was to test a novel catheter US technique for staging superficial esophageal carcinoma. METHODS: Twelve patients underwent examination with a 2-channel endoscope. US images were obtained with a catheter US probe (20 MHz) fitted with a balloon sheath. RESULTS: Adequate endoscopic and catheter US images were obtained in all patients. Depth of tumor invasion as determined with the catheter US probe was confirmed in all 5 patients who underwent surgery. No procedure-related complications occurred. CONCLUSIONS: US with a catheter US probe and sheath allows complete endoscopic examination and preoperative determination of depth of invasion of superficial esophageal carcinoma in a single endoscopic procedure. Preliminary results suggest this technique is accurate and safe.

Adenocarcinoma↗
PubMed2002

Utility of EUS in the evaluation of cystic pancreatic lesions.

BACKGROUND: Preoperative differentiation of benign and malignant/potentially malignant pancreatic cystic lesions is problematic. Data to support the role of EUS and EUS-guided fine-needle aspiration (EUS-FNA) are limited. This study assessed the sensitivity, specificity, and accuracy of EUS, cytopathology, and analysis of cyst fluid for pancreatic cystic lesions. METHODS: Retrospectively, 111 consecutive patients were identified (54 men, 57 women; mean age 59 years, range 18-79 years) who underwent EUS from July 1997 to September 2000 because of known or suspected pancreatic cystic lesions based on CT or transabdominal US. Thirty-four patients (16 men, 18 women; mean age 55 years, 25-79 years) who underwent surgery formed the basis for this analysis. EUS diagnosis was compared with surgical pathology. Selected patients underwent EUS-FNA to obtain specimens for cytopathologic analysis and for determination of carcinoembryonic antigen levels. Based on surgical pathology, cysts were classified as benign (simple cyst, pseudocyst, serous cystadenoma) or malignant/potentially malignant (mucinous cystadenoma, intraductal papillary mucinous tumor, cystic islet cell tumor, cystic adenocarcinoma). RESULTS: EUS-FNA with cytopathologic assessment of cyst fluid was performed for 18 of the 34 patients; carcinoembryonic antigen level was determined in 11 cases. For EUS, cytopathology, and carcinoembryonic antigen, sensitivity was, respectively, 91%, (p = 0.01 vs. cytology), 27%, and 28%; specificity was, respectively, 60%, 100%, and 25%; and, accuracy was, respectively, 82%, 55%, and 27%. The sensitivity of EUS in all 13 patients with cystic islet cell tumor, intraductal papillary mucinous tumor, or cystic adenocarcinoma was 100%. Combining EUS, cytopathology, and carcinoembryonic antigen results did not improve accuracy. There were no complications related to the EUS or EUS-FNA. CONCLUSIONS: EUS alone is sensitive and accurate in identifying malignant/potentially malignant pancreatic cystic lesions. EUS-FNA to obtain specimens for cytopathologic analysis and determination of carcinoembryonic antigen levels, although safe, does not enhance diagnostic yield.

Adolescent↗
PubMed2002

Evaluation of indeterminate bile duct strictures by intraductal US.

BACKGROUND: Cholangiography and tissue sampling (brush cytology, biopsy) are the standard nonsurgical techniques for determining whether a bile duct stricture is benign or malignant. The aim of this study was to determine whether intraductal US is of assistance in distinguishing benign from malignant biliary strictures. METHODS: A retrospective review was undertaken of 30 patients with indeterminate bile duct strictures who underwent ERCP and tissue sampling from September 1999 to November 2000. A 20 MHz over-the-guidewire intraductal US catheter probe was used during ERCP for further examination of the strictures. Final diagnoses of malignant strictures (18 patients) were confirmed histopathologically; confirmation of benign stricture (12 patients) was based on negative tissue sampling plus extended clinical follow-up. RESULTS: Based on retrospective blinded review, the diagnosis by ERCP was correct in 67% of patients, by tissue sampling in 68%, by combined ERCP/tissue sampling in 67%, and by intraductal US in 90% (p = 0.04 vs. ERCP/tissue sampling) of cases. No complication of intraductal US or ERCP was recorded. CONCLUSIONS: Intraductal US is safe and can improve on the ability at ERCP to distinguish benign from malignant biliary strictures.

Adolescent↗
PubMedDate not supplied

Comparison of positron emission tomography, computed tomography, and endoscopic ultrasound in the initial staging of patients with esophageal cancer.

INTRODUCTION: Improvement in esophageal cancer staging is needed. Positron emission tomography (PET), computed tomography (CT), and endoscopic ultrasound (EUS) in the staging of esophageal carcinoma were compared. METHODS: PET, CT, and EUS were performed and interpreted prospectively in 75 patients with newly diagnosed esophageal cancer. Either tissue confirmation or fine needle aspiration (FNA) was used as the gold standard of disease. Sensitivity and specificity for tumor, nodal, and metastatic (TNM) disease for each test were determined. TNM categorizations from each test were used to assign patients to subgroups corresponding to the three treatment plans that patients could theoretically receive, and these were then compared. RESULTS: Local tumor staging (T) was done correctly by CT and PET in 42% and by EUS in 71% of patients (P value > 0.14). The sensitivity and specificity for nodal involvement (N) by modality were 84% and 67% for CT, 86% and 67% for EUS, and 82% and 60% for PET (P value > 0.38). The sensitivity and specificity for distant metastasis were 81% and 82% for CT, 73% and 86% for EUS, and 81% and 91% for PET (P value > 0.25). Treatment assignment was done correctly by CT in 65%, by EUS in 75%, and by PET in 70% of patients (P value > 0.34). CONCLUSIONS: EUS had superior T staging ability over PET and CT in our study group. The tests showed similar performance in nodal staging and there was a trend toward improved distant disease staging with CT or PET over EUS. Assignment to treatment groups in relation to TNM staging tended to be better by EUS. Each test contributed unique patient staging information on an individual basis.

Endosonography↗