Analysis of variables associated with surgery versus observation in patients with pancreatic cystic lesions referred for endoscopic ultrasound.

BACKGROUND AND STUDY AIM: Endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) for cyst fluid analysis (CFA) is often requested for pancreatic cystic lesions, to determine whether to operate or to observe. If this decision is not influenced by the EUS findings, the procedure may be unjustifiable. We aimed to determine whether EUS-CFA results predict surgery or observation in patients with pancreatic cysts referred for EUS. PATIENTS AND METHODS: Consecutive patients referred to a quaternary pancreaticobiliary center for EUS evaluation of pancreatic cysts were eligible. Clinical data, computed tomography (CT) results, EUS findings, and CFA results were reviewed retrospectively. Statistical analysis was performed to determine variables associated with surgery versus observation. RESULTS: Over 33 months, data on 194 consecutive patients referred for EUS for evaluation of pancreatic cysts were analyzed. Of these, 136 (70 %) patients had EUS-FNA. After the initial workup (including EUS with/without CFA), 35 (18 %) underwent surgery. Predictors of surgery were: younger age (< 65 years) (P = 0.0027), malignant appearance at EUS (P = 0.02), and history of EUS-FNA (P = 0.012). Cyst fluid appearance, and carcinoembryonic antigen (CEA), carbohydrate antigen 19­9 (CA 19­9), and amylase levels were not significant determinants of surgery. In 14/50 (28 %) of cases where EUS-CFA clearly suggested benign serous lesions, surgery was still performed and in 9/11 (82 %) of cases with malignant EUS-CFA findings, surgery was not done. CONCLUSIONS: In patients with pancreatic cysts referred for EUS, age and EUS appearance independently predict surgery. The "perceived need for EUS-CFA" also predicts surgery, but not the EUS-CFA results. The clinical value of EUS-CFA requires further study.

A prospective comparison of endoscopic ultrasound-guided fine needle aspiration results obtained in the same lesion, with and without the needle stylet.

BACKGROUND AND STUDY AIMS: The effectiveness of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) with (S+) and without (S-) a stylet has never been compared. We prospectively compared the yield for malignancy and sample quality of S+ and S- EUS-FNA. PATIENTS AND METHODS: S+ or S- EUS-FNA was performed on consecutive solid lesions, with a 22-gauge needle, with systematic assignment of S+ or S- passes in a 1 : 2 ratio. Slides were read by a single, blinded cytologist and were rated for bloodiness, adequacy, and presence of malignancy. The yield for malignancy was compared only in lesions in which equal numbers of S+ and S- passes were performed. RESULTS: A total of 309 passes (mean 2.3 passes/lesion, range 1-6, 82% adequate, 38% S+, 62% S-) were performed on 135 lesions (63% malignant, 42% nodes, 58% masses [79% pancreatic]) in 111 patients (mean age 62.9 years, range 30-86). In 46 lesions where an equal number (53 S+ and 53 S-) of passes was performed, there was no difference in the proportion of cases in which S+ FNA was "equal to or better than" S- FNA ([S+] 89% vs. [S-] 87%; P>0.05). The results of the two methods agreed in 80% cases (kappa 0.60). The sensitivities for malignancy were: S+ 87% vs. S- 83%, P>0.05. Specificities were 100%. Sample adequacy was significantly lower in S+ passes (75% vs. 87%, P=0.013), and sample bloodiness was significantly higher (75% vs. 52%, P<0.0001). CONCLUSIONS: Use of the stylet with EUS-FNA does not increase the yield for malignancy and is associated with poorer sample quality. The value of the stylet for EUS-FNA is questionable and requires further investigation.

Helicobacter pylori eradication is superior to ulcer healing with or without maintenance therapy to prevent further ulcer haemorrhage.

BACKGROUND: Helicobacter pylori eradication decreases ulcer recurrence and should prevent recurrent ulcer haemorrhage. AIM: By meta-analysis, to compare treatment of H. pylori infection with other approaches to prevent recurrent ulcer haemorrhage and, by cost minimization analysis, to determine the least costly strategy. METHODS: We searched for randomized, controlled trials comparing treatment of H. pylori infection with ulcer healing alone or with maintenance therapy in preventing recurrent ulcer haemorrhage. We calculated the relative and absolute risk reductions and numbers needed to treat. RESULTS: Treatment of H. pylori infection decreased recurrent bleeding by 17% (numbers needed to treat=6) compared with ulcer healing treatment alone. Compared with ulcer healing treatment followed by maintenance therapy, recurrent bleeding was decreased by 4% (numbers needed to treat=25). Decision model-based cost minimization analysis demonstrated that treatment of H. pylori infection was the least costly strategy unless the incidence of complicated recurrences after treatment was over 6%, or the cost of confirming eradication was over $741. CONCLUSIONS: Treatment of H. pylori infection is superior to ulcer healing treatment with or without maintenance therapy in preventing recurrent ulcer haemorrhage. All patients with ulcer bleeding should be tested for H. pylori infection and appropriately treated if positive.

Esophageal cancer staging: improved accuracy by endoscopic ultrasound of celiac lymph nodes.

BACKGROUND: Clinical staging of esophageal cancer is required for optimal therapy but remains imprecise. Pathologic verification of involved lymph nodes could potentially direct treatment allocation. With the rising incidence of distal and gastroesophageal junction adenocarcinomas, assessment of the celiac axis lymph nodes (CLNs) becomes important because it is a common nodal drainage basin. Endoscopic ultrasound (EUS) permits evaluation of CLNs and biopsy by fine-needle aspiration. This study examined the usefulness of this staging tool. METHODS: A consecutive series of 62 patients with esophageal cancer considered resectable by computed tomographic scan underwent EUS for T and N staging and were retrospectively studied. A CLN visualized by EUS as greater than 5 mm was considered positive. Fine-needle aspiration of the CLN was performed routinely. Endoscopic ultrasound and computed tomographic staging were compared on the basis of pathologic verification of CLNs. RESULTS: It was possible to evaluate CLNs by EUS in 59 (95%) of 62 patients: positive in 19, negative in 40. In EUS-positive patients, fine-needle aspiration was positive in 15, falsely negative in 2, and not done in 2. By computed tomographic scan, CLNs were negative in 57 patients and positive in 2. The CLNs were positive in 23 of 54 patients eligible for CLN pathologic verification. All positive CLNs not identified by EUS (7 false-negative EUS) were microscopic foci in one or two nodes and were associated with T3 tumors. Sensitivity and specificity of EUS were 72% and 97%, respectively, compared with 8% and 100% for computed tomographic scan. When EUS identified CLNs, fine-needle aspiration confirmed positivity in 88% of cases. CONCLUSIONS: Endoscopic ultrasound with fine-needle aspiration is useful in the detection and confirmation of CLN metastasis. In T3 tumors of the distal esophagus, a negative EUS result does not substantiate absence of CLN disease. Endoscopic ultrasound with fine-needle aspiration may be important in guiding treatment for patients with distal adenocarcinoma and documenting disease before neoadjuvant therapy.

Endoscopic ultrasound-guided fine needle aspiration for staging patients with carcinoma of the lung.

BACKGROUND: Endoscopic ultrasound (EUS)-guided fine needle aspiration is a safe, cost-effective procedure that can confirm the presence of mediastinal lymph node metastases and mediastinal tumor invasion. We studied the accuracy of EUS in a large population of lung cancer patients with and without enlarged mediastinal lymph nodes on computed tomographic (CT) scan. METHODS: From 1996 to 2000 all patients referred to our institution with lung tumors and no proven distant metastases were considered for EUS and surgical staging. Patients had endoscopic ultrasound with fine needle aspiration of abnormal appearing mediastinal lymph nodes and evaluation for mediastinal invasion of tumor (stage III or IV disease). Patients without confirmed stage III or IV disease had surgical staging. RESULTS: Two hundred seventy-seven patients met the inclusion criteria, including 121 who had EUS. Endoscopic ultrasound and fine needle aspiration detected stage III or IV disease in 85 of 121 (70%). Among patients with enlarged lymph nodes on CT, 75 of 97 (77%) had stage III or IV disease detected by EUS. Among a small cohort of patients without enlarged mediastinal lymph nodes on CT, 10 of 24 (42%) had stage III or IV disease detected by EUS. For mediastinal lymph nodes only, the sensitivity of endoscopic ultrasound and CT was 87%. The specificity of EUS (100%) was superior to that of CT (32%) (p < 0.001). CONCLUSIONS: Endoscopic ultrasound with fine needle aspiration identified and histologically confirmed mediastinal disease in more than two thirds of patients with carcinoma of the lung who have abnormal mediastinal CT scans. Although mediastinal disease was more likely in patients with an abnormal mediastinal CT, EUS also detected mediastinal disease in more than one third of patients with a normal mediastinal CT and deserves further study. Endoscopic ultrasound should be considered a first line method of presurgical evaluation of patients with tumors of the lung.

Disease-specific outcomes assessment for common bile duct stones.

Clinicians often manage patients with suspected bile duct stones. Research has focused on assessing the accuracy of diagnostic alternatives to endoscopic retrograde cholangiography or on establishing predictors for stones. Studies using costs and quality of life as primary outcomes are rare. This may be caused in part by specific challenges inherent to outcomes research in the field of gastrointestinal endoscopy. It is unlikely that one strategy will be suitable for all; however, once a primary outcome is chosen, knowing what variables most affect this outcome should help clinicians objectively tailor the optimal strategy for their needs. The most important variable may be the risk of symptoms caused by untreated stones. There may be a substantial group of patients who are best managed expectantly (with no bile duct imaging). It may therefore, be useful to obtain better prospective data on the natural history of choledocholithiasis.

Endoscopic ultrasonography in the diagnosis and staging of pancreatic neoplasms.

BACKGROUND: Pancreatic cancer is the fourth leading cause of death among Americans. Twenty-eight thousand cases of pancreatic cancer are diagnosed annually and about the same number of patients die of pancreatic cancer every year. Most patients with pancreatic cancer are diagnosed when the tumor is 3 cm or more in diameter. Most pancreatic cancers are metastatic at the time of diagnosis and the median survival is only 18-20 mo. Overall, actual 5-yr survival is about 10% and has not changed much over several decades. Curative surgical resection is currently believed to offer the only chance of long-term survival in these patients. Difficulty in the early diagnosis of pancreatic cancer remains a major obstacle in improving outcomes in these patients. Screening for pancreatic cancer is currently not recommended. However, recent developments in endoscopic ultrasound (EUS) and cytological EUS-guided fine-needle aspiration (FNA) allow early diagnosis of pancreatic cancer with histological confirmation. EUS-FNA in conjunction with helical CT also provides reliable preoperative staging of pancreatic tumors. EUS with FNA therefore appears to be a promising tool in the fight against pancreatic cancer.

Cost-effectiveness studies in endoscopy: are they worth it?

Cost-effectiveness analysis is currently in great demand. Evaluating the cost-effectiveness of endoscopy in comparison with surgical and radiological alternatives for diagnosis and therapy would appear particularly important, since the costs they incur may be substantial. However, several technical and practical issues may limit the perceived value of cost-effectiveness studies and the applicability of their results to daily practice. Despite this, they are likely to be used to make decisions regarding health-care resource allocation. A better understanding of their limitations by all parties involved and active participation by physicians (as opposed to health-care administrators) in their conception and execution should help optimize our ability to provide excellent patient care at a reasonable price.

An assessment of the use of costs and quality of life as outcomes in endoscopic research.

BACKGROUND: Costs and quality of life are increasingly important study outcomes. We quantitatively and qualitatively assessed their use in recent endoscopic research. METHODS: All Medline-retrieved 1985 to 1995 published gastrointestinal endoscopic research using cost and/or quality of life as outcomes were analyzed. RESULTS: Sixty-eight (1.2%) of an estimated 5568 publications discussed costs and/or quality of life as endoscopic outcomes (24 quality of life, 37 cost-effectiveness, 7 cost-benefit). Their use did not increase with time. Cost or quality of life was infrequently a primary study outcome. Twenty of 24 (83%) quality of life papers used an objective scale. However, of these, 15 of 20 (75%) used symptom indexes, performance scales, or other nonvalidated quality of life instruments. Two of 24 (8%) evaluated quality of life in nonmalignant disease. Eight of 40 (20%) papers claimed endoscopy was cost-effective, with no evidence of formal cost assessment. Ten of 32 (31%) substituted charges for costs. Of 21 papers reporting cost data, 4 (19%) specified cost type (e.g., direct vs other), 6 (29%) specified cost perspective, and 9 (43%) reported sensitivity analysis. Sixteen of 27 (59%) cost-effectiveness papers did not correlate costs with changes in a health outcome. CONCLUSIONS: The overall cost and quality of life assessment in endoscopic research has been limited and must be improved. Accurate cost and quality of life assessment will require cooperation between gastroenterologists and experts in these fields.

Bile duct stones and laparoscopic cholecystectomy: a decision analysis to assess the roles of intraoperative cholangiography, EUS, and ERCP.

BACKGROUND: The least costly management strategy for patients undergoing laparoscopic cholecystectomy is unclear. METHODS: A decision model incorporating cost ratios, test accuracy, complication, and failure rates was used to determine the costs of 4 peri-laparoscopic cholecystectomy strategies: endoscopic retrograde cholangiopancreatography (ERCP), intraoperative cholangiography (IOCG), endoscopic ultrasound (EUS), and expectant management. RESULTS: Expert IOCG is least costly for intermediate-risk patients when the risk of stones is between 17% and 34%. If expert EUS is available, 0% to 10% ("low" risk) merits expectant management; 11% to 55% ("intermediate" risk) merits EUS; and greater than 55% ("high" risk) merits ERCP. Thresholds were most sensitive to changes in the risks of symptoms and complications due to retained stones; and to procedural costs, sensitivity, and success rates. Neither IOCG nor EUS appears likely to reduce overall costs unless their accuracy and success rates are greater than 90% and their procedural cost is less than 60% to 70% that of ERCP. When neither are available, ERCP is preferable when the risk of stones is greater than 22%. Thresholds were relatively insensitive to changes in the risk and severity of ERCP-induced pancreatitis. CONCLUSIONS: The least costly strategy for laparoscopic cholecystectomy patients depends primarily on the risk of stones and stone-related symptoms, but procedural costs and operator expertise are also critical.

Dilation of malignant esophageal stenosis to allow EUS guided fine-needle aspiration: safety and effect on patient management.

BACKGROUND: Endoscopic ultrasonography (EUS) with fine-needle aspiration identifies patients with esophageal cancer who are unlikely to be cured by surgery. In approximately 30% of patients the staging procedure cannot be completed without dilation of an obstructing tumor. METHODS: All EUS examinations for esophageal cancer requiring dilation from July 1995 to December 1998 were included. Yield was defined as newly diagnosed metastatic (celiac lymph nodes) or locally invasive disease that could not have been detected without dilation. RESULTS: EUS was performed in 132 patients. Forty-two (32%) required 44 dilations. No complications occurred. Of the 42 patients with obstruction, 18 (43%) had celiac adenopathy of which 7 had malignant cells confirmed histologically, 3 had benign adenopathy, and 8 did not undergo fine-needle aspiration due to T4 stage disease (5) or intervening vessels (3). Two patients were upstaged after successful dilation from T2 N1 Mx to T4 N1 Mx and from T3 Nx Mx to T3 N1 M1. Overall, dilation allowed detection of advanced disease in 8 of 42 (19%) patients. Dilation to 11 to 12.8 mm was insufficient (36% success rate) to complete EUS compared with dilation to 14 to 16 mm (87%, p < 0.01). CONCLUSION: Dilation of obstructing esophageal tumors allows identification of a large number of patients with advanced stage malignancy. Dilation to 14 to 16 mm is sufficient for complete staging in almost all patients.

EUS to detect evidence of pancreatic disease in patients with persistent or nonspecific dyspepsia.

BACKGROUND: Mild chronic pancreatitis is difficult to diagnose and the diagnosis is therefore not sought routinely in patients with dyspepsia. The aim of our study was to compare the prevalence of endosonographic pancreatic abnormalities in patients with dyspepsia and control subjects. METHODS: The number of endosonographic abnormalities was compared prospectively in patients with dyspepsia and control patients. Patients in whom there was any suspicion of pancreatic disease were analyzed separately. RESULTS: Between November 1998 and January 1999, 156 patients with dyspepsia were compared with 27 control patients. The groups were similar except that control patients were significantly older and more likely to be men. The mean number of endosonographic abnormalities was higher in dyspeptic patients than in control patients (mean number of abnormalities 3.3: 95% CI [2.9, 3.6] vs. 1.9: 95% CI [0.3, 1.7]). The strongest independent predictors of severe endosonographic abnormalities (defined as 5 or more abnormalities) were the presence of suspected pancreatic disease (odds ratio 7.29: 95% CI [2.03, 26. 14]) and dyspepsia (odds ratio 7.21: 95% CI [1.99, 26.26]). In the dyspepsia group, no clinical variables were significant predictors of severe abnormalities. However, most patients had nonspecific-type dyspepsia or persistent symptoms after therapeutic trials of acid suppression. CONCLUSIONS: Dyspepsia may be an atypical presentation of pancreatic disease in patients with persistent or nonspecific symptoms. Endosonography may be useful to screen for pancreatic disease in patients with persistent dyspepsia.

An assessment of the potential value of endoscopic ultrasound as a cost-minimizing tool in dyspeptic patients with persistent symptoms.

STUDY AIMS: To quantify resource utilization in dyspeptic patients with persistent symptoms and to determine whether using both the endoscopic and ultrasound capabilities of endoscopic ultrasound could reduce costs. METHODS: Consecutive patients with persistent dyspepsia, after a minimum 1-month trial of acid suppression, underwent endoscopic ultrasound (EUS) and upper endoscopy using the GF-UM20 echo endoscope. Assuming EUS could replace imaging tests which had been requested in addition to upper endoscopy, the hypothetical costs of the EUS-based and upper endoscopy-based strategies were compared. RESULTS: 116 patients with persistent dyspepsia underwent EUS, of whom 64.6 % had > or = 2 imaging procedures, most commonly computed tomography (CT) (70.6 %) and abdominal ultrasound (64.7 %). The number of tests did not correlate strongly with any demographic variables. The fiberoptic echo endoscope provided an adequate endoscopic and ultrasound examination but was damaged by retroflexion. Direct hospital costs were lowest for the EUS-based strategy. Total avoidable cost for 116 patients was $ 4137 to $ 14 121 (or $ 36 to $ 122 per patient), depending on whether upper endoscopy was performed in the non-EUS strategies. CONCLUSIONS: Patients with persistent dyspepsia may undergo multiple abdominal imaging procedures. Clinical variables do not predict the need for additional testing. An EUS-based strategy may reduce overall costs if it prevents additional testing.

CT or EUS for the initial staging of esophageal cancer? A cost minimization analysis.

BACKGROUND: Patients with advanced (T4 and/or M1) esophageal cancer are offered palliative therapy. Computed tomography (CT) is sensitive for distant metastases but is less sensitive than endosonography for T4 disease and celiac lymphadenopathy. The aim of this study was to determine whether initial CT or endosonography costs less to diagnose advanced esophageal cancer. METHODS: A decision model compared the costs of the 2 strategies. Sensitivity analysis and threshold analysis were used to identify the most important determinants of the overall cost of identifying advanced disease. RESULTS: Initial CT is the least costly strategy if the probability of finding advanced disease by initial CT is greater than 20%, if the probability of finding advanced disease by initial endoscopic ultrasound (EUS) is less than 30%, or if the cost of EUS is greater than 3.5 times the cost of CT. However, in our referral center population, endosonography found advanced disease more frequently than CT (44% vs. 13%; p < 0.0001) and the least costly strategy was initial endosonography (expected cost $804 vs. $844). CONCLUSION: CT remains as the initial staging test of choice in most clinical settings. However, in referral centers, initial EUS may be reasonable, but individualized model inputs must be obtained before reliable conclusions can be drawn.

Prospective assessment of the ability of endoscopic ultrasound to diagnose, exclude, or establish the severity of chronic pancreatitis found by endoscopic retrograde cholangiopancreatography.

BACKGROUND: Our aim was to verify endoscopic ultrasound (EUS) accuracy to diagnose, rule out, and establish the severity of chronic pancreatitis found by endoscopic retrograde cholangiopancreatography (ERCP). METHODS: Patients undergoing ERCP for unexplained abdominal pain and/or suspected chronic pancreatitis underwent EUS. EUS was performed by experienced operators who were aware of the history but blinded to ERCP results. Chronic pancreatitis was defined using the Cambridge classification: 0 to 1 = "normal," 2 to 4 = "all chronic pancreatitis," 3 to 4 = "moderate to severe chronic pancreatitis." The number of EUS criteria required to obtain sensitivity, specificity, positive and negative predictive values > or = 85% was determined. EUS criteria for chronic pancreatitis are hyperechoic foci, hyperechoic strands, lobularity, hyperechoic duct, irregular duct, visible side-branches, ductal dilation, calcification, and cysts. RESULTS: One hundred twenty-six patients underwent EUS and ERCP. EUS was highly sensitive and specific (> 85%) depending on the number of criteria present. Chronic pancreatitis is likely (PPV > 85%) when more than two criteria (for "all chronic pancreatitis") and more than six criteria (for "moderate to severe chronic pancreatitis") are present. "Moderate to severe chronic pancreatitis" is unlikely (NPV > 85%) when fewer than three criteria are present. Independent predictors of chronic pancreatitis were "calcification" (p = 0.000001), history of alcohol abuse (p = 0.002), and the total number of EUS criteria (p = 0.008). CONCLUSIONS: EUS can accurately diagnose, rule out, and establish the severity of chronic pancreatitis found by ERCP.

Endoscopic ultrasonography with fine-needle aspiration: an accurate and simple diagnostic modality for sarcoidosis.

BACKGROUND AND STUDY AIMS: Sarcoidosis is a chronic multisystem granulomatous disease that is often diagnosed after a finding of hilar and mediastinal lymphadenopathy on a chest radiograph. This often requires further evaluation by transbronchial biopsy or other clinical parameters. The present study is a descriptive, retrospective one using endoscopic ultrasound with fine-needle aspiration (EUS-FNA) of mediastinal lymph nodes in seven patients with sarcoidosis. PATIENTS AND METHODS: Among 108 consecutive patients who underwent EUS-FNA of mediastinal lymph nodes for various clinical indications between July 1994 and October 1997, seven patients were found to have sarcoidosis on EUS-FNA, and the EUS morphology was studied in these patients. RESULTS: Sarcoidosis was diagnosed in seven patients using endosonographic characteristics and clinical follow-up. EUS with FNA showed cytological evidence of sarcoidosis in six patients. Seven patients were found to have subcarinal lymph nodes, and six patients had abnormally enlarged aortopulmonary (AP) window lymph nodes. The nodes in all patients had three endosonographic criteria for malignancy. The long axis of the largest mediastinal lymph nodes measured 3.44+/-1.42 cm (range 1.8-6.0 cm). The short axis measured 2.50+/-0.69 (range 1.0-4.0 cm). The average number of nodes seen in each patient was 2.80+/-0.75 (range 2-4). The nodes in all seven patients were discrete and well demarcated. A central hyperechoic strand was evident in these nodes in four patients (57%). There were no complications. CONCLUSIONS: Mediastinal lymph nodes in patients with sarcoidosis appear to have specific echo characteristics, and EUS-FNA can be used for confirmatory tissue diagnosis.

Endoscopic ultrasound guided fine needle aspiration biopsy: a large single centre experience.

BACKGROUND: Endoscopic ultrasound guided fine needle aspiration biopsy (EUS-FNA) is a recent innovation in the evaluation of gastrointestinal and pulmonary malignancies. AIMS: To review the experience with EUS-FNA of a large single centre. METHODS: 333 consecutive patients underwent EUS-FNA. Follow up data were available on 327 lesions in 317 patients, including 160 lymph nodes, 144 pancreatic lesions, 15 extraintestinal masses, and eight intramural tumours. RESULTS: A primary diagnosis of malignancy was obtained by EUS-FNA in 62% of patients with clinically suspicious lesions. The overall accuracy of EUS-FNA for the diagnosis of malignancy was 86%, with sensitivity of 84% and specificity of 96%. With respect to lesion types, the sensitivity, specificity, and accuracy were 85%, 100%, and 89% for lymph nodes; 82%, 100%, and 85% for pancreatic lesions; 88%, 100%, and 90% for perirectal masses; and 50%, 25%, and 38% for intramural lesions, respectively. Compared with size and sonographic criteria, EUS-FNA in the evaluation of lymph nodes provided superior accuracy and specificity, without compromising sensitivity. Inadequate specimens were obtained from only six patients, including 3/5 with stromal tumors. Only one complication occurred. CONCLUSIONS: EUS-FNA is safe and can readily obtain tissue specimens adequate for cytopathological diagnoses. Compared with size and sonographic criteria, it is a superior modality for the detection of nodal metastases. While providing accurate diagnosis of pancreatic and perirectal malignancies, results suggest the technique is less useful for intramural lesions.

A multicenter U.S. experience with EUS-guided fine-needle aspiration using the Olympus GF-UM30P echoendoscope: safety and effectiveness.

BACKGROUND: The aim of this study was to determine the safety, efficacy, and accuracy of endoscopic ultrasound (EUS)-guided fine-needle aspiration using the GF-UM30P echoendoscope. METHODS: GF-UM30P-guided EUS-guided fine-needle aspiration results from 3 EUS referral centers were prospectively recorded. Successful sampling required that the needle tip be seen within the lesion on at least 1 pass. Aspirates were considered adequate if they were diagnostic for cancer, contained suspicious or atypical cells, or were adequately cellular for interpretation but nondiagnostic. RESULTS: EUS-guided fine-needle aspiration was attempted on 162 lesions in 152 patients with no complications. Sampling was successful in 150 of 162 (93%) attempts (mean lesion size 2.5 +/- 1.2 cm (range 0.7 to 6.0 cm). Aspirates were adequately cellular in 138 of 162 (85%) attempts (43% diagnostic, 15% suspicious and/or atypical cells, 27% adequate cellularity but nondiagnostic). Sampling failed in 12 of 162 (7%) attempts. Ten of 12 (83%) failures and 11 of 12 (92%) inadequate aspirates occurred when lesions measured less than 2 cm. The sensitivity for malignancy was 93% if only successfully sampled lesions with surgically confirmed negative results were included. However, it was 68% if all attempts were included and when unconfirmed high/moderate suspicion negative results were counted as false negatives and low suspicion negative results as true negatives. CONCLUSIONS: The GF-UM30P may be clinically useful for EUS-guided fine-needle aspiration if a curved linear array instrument is unavailable.