Endoscopic ultrasonography in the evaluation of leiomyoma and extramucosal cysts of the esophagus

BACKGROUND/AIMS: Leiomyoma is the most common type of benign esophageal tumor, whereas extramucosal cysts of the esophagus are congenital anomalies frequently asymptomatic in the adult and in most cases detected incidentally on chest x-ray. It is worthwhile considering these conditions together, because they present similar diagnostic and surgical problems. Conventional imaging tests do not lead to a precise diagnosis. The purpose of this study was to evaluate the use of endoscopic ultrasonography in the diagnosis of, and planning of treatment modalities for, these conditions. METHODOLOGY: Fifteen patients with esophageal leiomyoma and seven patients with extramucosal esophageal cysts were studied with endoscopic ultrasonography using an Olympus GF- EU-M3 instrument with a 7.5-12 MHz echoprobe. In all patients, the results of endoscopic ultrasonography were compared with the histology of the resected specimens. RESULTS: The histology of the resected specimens confirmed the endosonographic diagnosis in all patients. No malignancy was found in any specimen. CONCLUSIONS: Endoscopic ultrasonography is very accurate in visualizing these lesions and differentiating cystic from solid submucosal esophageal masses; in addition, the test can establish the exact location of the mass in relation to the esophageal wall and mediastinum. Therefore, endoscopic ultrasonography has a great impact in confirming the diagnosis of leiomyoma and extramucosal cysts of the esophagus and facilitates therapeutic decision-making because of its capacity to clearly define the size, layer of the origin, and pattern of the mass.     

Biopsy-negative malignant esophageal stricture: diagnosis by endoscopic ultrasound

Endoscopic ultrasound (EUS) of the esophagus has been used primarily in staging biopsy-proven cancers. Its use as a primary diagnostic modality for esophageal malignancy has not been previously described. We report our recent experience in four patients with dysphagia and endoscopic biopsies negative for malignancy, including one patient with clinical and manometric features suggestive of achalasia. In all cases, EUS revealed a large infiltrating tumor invading through the esophageal wall into the surrounding tissues, and in one case into the aorta. Computed tomography suggested the possibility of a tumor in only one of the cases. Two patients underwent esophagectomy and were found to have adenocarcinoma. Two patients underwent repeat biopsy with alternative aggressive biopsy techniques and were found to have squamous cell carcinoma. We conclude that EUS is useful in the diagnosis of esophageal cancer and should be performed in selected patients with esophageal strictures whose biopsies are negative for malignancy; i.e., those with suspicious endoscopic or radiographic appearance, atypical presentation (e.g., profound weight loss, short duration of symptoms, or advanced age), and failure to respond to treatment.     

Thoracoscopic excision of an uncertain intramural esophagus tumor (granular cell tumor/Abrikossoff tumor)

A granular cell tumor is one of the rare tumors of the esophagus. We present the case of a 65-year-old male patient, who was admitted to our hospital for an elective cholecystectomy. In the routine diagnostic gastroscopy an intramural tumor in the distal esophagus was incidentally found. Repeated endoscopic biopsies did not reveal the histologic diagnosis, although endoscopic ultrasound invasion to the tunica muscularis could not be excluded. After indicating the operative therapy, the tumor was removed through a thoracoscopic approach. The histologic specimen showed a granular cell tumor of the esophagus (tumor of Abrikossoff). Since the tumor grade was unknown, our therapy seemed to be justified because of the low risk involved in minimally invasive operative procedures. There has been much discussion and controversy in the literature on this subject, including the potential for malignancy and the correct therapy regime, with a general shift to conservative or minimally invasive treatment. The case is discussed with a review of the literature.     

Barrett's esophagus, high-grade dysplasia, and early adenocarcinoma: a pathological study

OBJECTIVES: In Barrett's esophagus, early adenocarcinomas are often missed on endoscopic biopsy. We therefore examined the distribution and extent of dysplasia and carcinoma in the resected esophagus for comparison with the preoperative biopsy findings. METHODS: Patients whose endoscopy showed Barrett's esophagus but no visible cancer had four-quadrant esophageal biopsies taken every 2 cm. After resection for high-grade dysplasia or early adenocarcinoma, the esophagus was mapped histologically. RESULTS: Nineteen patients had surgery for high-grade dysplasia; two of them (10.5%) had adenocarcinoma in the resected esophagus. Eleven patients had resection after a biopsy diagnosis of adenocarcinoma or suspicion of adenocarcinoma. Esophagectomy mapping confirmed carcinoma in only five of them. Median surface areas were: total Barrett's esophagus 32 sq cm, low-grade dysplasia 13 sq cm, high-grade dysplasia 1.3 sq cm, adenocarcinoma (seven cases) 1.1 sq cm. CONCLUSIONS: Areas of high-grade dysplasia and microscopic carcinoma in Barrett's esophagus are often small. Biopsy differentiation between these lesions is difficult. A systematic endoscopic biopsy protocol will reduce the chance of missing early malignancy in Barrett's esophagus.     

Functional and structural properties of Na+/K(+)-ATPase enzyme in neonatal erythrocytes

Achalasia is a relatively infrequent disorder of oesophageal motility, and is most often easily diagnosed by stationary manometry showing absence of peristalsis and incomplete lower oesophageal sphincter (LOS) relaxation. In rare cases manometric findings may be inconclusive or a malignant underlying disease is suspected. In such cases direct visualization of the LOS by endoscopic ultrasound (EUS) could contribute to securing the diagnosis and possibly lead to earlier diagnosis and treatment. With lower frequency EUS, increased thickness of the inner circular layer of the muscularis propria may be difficult to detect. Available data suggest that high frequency (20 MHz) and 3-D EUS has a potential to reliably discriminate between achalasia patients and normal subjects, and thereby be of diagnostic value.     

Initial experiences with magnetic resonance endoscopy

BACKGROUND: In contrast to endorectal surface coils used to assess pelvic tumors, the magnetic resonance endoscope (MR) has all the features of a standard endoscope. In ex-vivo imaging of the porcine gastrointestinal tract, endoscopic MR demonstrates distinct histological layers of the gastrointestinal wall. The aim of this study was to assess the feasibility and the accuracy of endoscopic MR in local staging of patients with esophageal and rectal cancer. METHODS: From April to August 1996, 12 patients (5 female and 7 male, mean age 63 [range 44-84] years) with histologically proven esophageal (n = 6) and rectal (n = 6) cancer prospectively underwent endoscopic ultrasound (EUS) followed by endoscopic MR. The two radiologists reviewing the endoscopic MR images were blinded to the EUS results. Assessment of T and N stages was compared to EUS and histology. RESULTS: Endoscopic MR was well tolerated in all patients and there were no complications. Image quality was sufficient in 75%. Endoscopic MR T-staging correlated with EUS and histology in 7/12 and 5/7 patients respectively. Discordance was due to overstaging by endoscopic MR. N-staging correlated with EUS and histology in 10/12 and 6/8 cases respectively. Non-correlation was due to a number of false negative results at endoscopic MR. CONCLUSION: These early results demonstrate endoscopic MR to be feasible and to produce comparable local staging to EUS in patients with esophageal and rectal cancer. The ultimate goal will be to combine endoscopic MR with body coil MR imaging (for the assessment of distant metastases) in order to provide "one-step staging" for the entire evaluation of gastrointestinal tumors.     

Diffuse cystic malformation and neoplasia-associated cystic formation in the stomach. Endosonographic features and diagnosis of tumor depth

We have evaluated the endoscopic ultrasonography (EUS) features of cystic malformation of the stomach and the depth of associated neoplasia. We included 15 patients with multiple cystic components identified on EUS: 6 patients with multiple cysts restricted focally to gastric neoplasia and 9 patients with diffusely distributed cysts. We categorized the former findings as focal cystic malformation (FCM), and the latter as diffuse cystic malformation (DCM) of the stomach and reviewed the endosonographic features. Both FCM and DCM tended to show male preponderance and develop in older patients. Cystic changes in FCM extended from the neoplastic lesion to the submucosa regardless of the location in the stomach. Diffuse cystic malformation was located predominantly in the gastric body and mainly was shown as the thickened submucosa and/or deep mucosa with multiple cystic components. The boundary between the mucosal layer or the tumor echo and the submucosal layer was indistinct in eight patients, which led to a lower accuracy in EUS diagnosis of tumor depth. Diffuse cystic malformation has characteristic EUS features and occasionally is accompanied by gastric neoplasia. Endoscopic ultrasonography is inaccurate in determining tumor depth when multiple submucosal cysts are present.     

Total thoracic esophagectomy for esophageal cancer

BACKGROUND: Many current methods of esophageal resection have drawbacks that result in inadequate proximal resection, inadequate lymphadenectomy, and difficult gastric and splenic access. We describe a technique that allows reliable and safe access to the chest, abdomen, and neck. STUDY DESIGN: From 1988 to 1995, 113 patients (82 men; mean age 65.3 +/- 4.5 years) with carcinoma of the esophagus or esophagogastric junction (middle third in 34, lower third in 41, and cardia in 38) underwent total thoracic esophagectomy. The histology was adenocarcinoma in 71 (62.8%), squamous cell carcinoma in 32 (28.3%), and undifferentiated carcinoma in 10 (8.9%) of the patients; 57 tumors (50.5%) were stage III. The esophagus and stomach were mobilized through a left thoracoabdominal incision. After completion of the esophageal resection, the fundus of the stomach was sutured to the esophageal stump to allow later delivery of the stomach into the neck. The esophagogastric anastomosis was performed with continuous single-layer absorbable suture through a left oblique cervical incision. RESULTS: The mean duration of the operation was 309.2 +/- 47.9 minutes. Hospital stay ranged from 5 to 49 days (median, 12 days). The perioperative mortality rate was 4.4%. Anastomotic leak occurred in six patients (5.3%), one of whom died. The proximal resection margin was microscopically free of tumor in all cases, and with a minimum followup period of 18 months, there has been no anastomotic recurrence in any patient. Actuarial survival at 1 year was 63.4% +/- 4.9%, at 3 years 41.4% +/- 5.9%, and at 5 years 22.7% +/- 6.3%. CONCLUSIONS: Total thoracic esophagectomy through the left chest with a separate left cervical incision allows clear access to the esophagus and stomach and good tumor clearance. This procedure may be performed with a low rate of anastomotic leakage, a very low mortality rate, and no anastomotic tumor recurrence.     

Micrometastasis and tumor cell microinvolvement of lymph nodes from esophageal squamous cell carcinoma: frequency, associated tumor characteristics, and impact on prognosis

BACKGROUND: The purpose of this study was to investigate micrometastasis (MM) and tumor cell microinvolvement (TCM) in the regional lymph nodes of patients with esophageal squamous cell carcinoma (SCC). METHODS: MM was defined as individual tumor cells or tumor cell clusters <0.5 mm in greatest dimension with a surrounding stromal reaction. TCM was defined as individual tumor cells or tumor cell clusters without a surrounding stromal reaction. One thousand nine hundred and fifty-four lymph nodes were dissected from 69 complete (R0) resection specimens of TNM classified pT1-3, pN0 or pN1, and M0 esophageal SCC. These lymph nodes were examined immunohistochemically using the monoclonal antibody cocktail AE1/AE3 for cytokeratins. The primary tumors were immunostained with an anti-E-cadherin monoclonal antibody. RESULTS: MM +/- TCM was found in 13 cases (31.7%) and TCM alone in 2 cases (4.9%) of the 41 pN0 cases. The pN0 patients with MM (but not TCM) had the same shorter survival as the original pN1 cases (P < 0.05). Of the 69 primary tumors, 49 (71.0%) had reduced or negative E-cadherin expression that showed a correlation with the occurrence of lymph node metastases (original pN1), MM, and TCM, but not prognosis. CONCLUSIONS: The results of the current study show that, in SCC of the esophagus, MM, but not TCM, in the regional lymph nodes is prognostically equivalent to metastasis and should be examined by immunohistochemistry to classify these cases correctly as pN1.     

Diagnosis of depth of invasion of gallbladder carcinoma with endosonography

We reported on the usefulness of endosonography (EUS) in the diagnosis of the depth of invasion of gallbladder carcinoma. We performed EUS on 69 patients with gallbladder carcinoma: the degree of tumor extension in 17 was m (tumor invading the mucosa), in 5 pm (tumor invading the muscular layer), in 21 ss (tumor invading the subserosa), 14 in se (tumor invading the serosa), and 12 si (tumor extending to adjacent organs). The detection rate of tumors with EUS was 91.3% (63 of 69). All 6 (100%) patients with pedunculated lesions (Ip type) were correctly diagnosed with EUS. Eighteen of 21 patients (85.7%) with broad-based elevated tumors (Is type), and 5 of 7 (71.4%) with flat-elevated lesions (IIa type) were also diagnosed correctly. EUS is a useful modality for the diagnosis of gallbladder carcinoma. In particular, EUS diagnosis of the depth of invasion is reliable in Ip-type lesions. It is recommended that patients with Ip-type lesions undergo laparoscopic cholecystectomy, but in patients with Is-or IIa-type lesions conventional cholecystectomy with lymph node resection should be performed.     

Neurofibroma of the esophagus

Benign esophageal tumors occur infrequently, with leiomyomas accounting for approximately 70% of cases. Benign neural tumors of the esophagus account for 200 cases reported in the literature and rarely require operative resection. The case of a 58-year-old woman with a 4-month history of progressive dysphagia and odynophagia is presented. A large intramural esophageal mass was resected through a right thoracotomy, and the esophagus was primarily repaired. Histologic examination revealed a neurofibroma.     

Endoscopic ultrasonography in the local staging of primary gastric lymphoma

Endoscopic ultrasonography (EUS) and endoscopy were prospectively performed and compared to the histopathologic findings of the resection specimens in 24 patients with primary gastric lymphoma (PGL). On EUS, three types of PGL could be differentiated, a superficial type (n = 10), an infiltrating type (n = 12) and a tumorous type (n = 2). In the correct assessment of surface extension of the tumors, endoscopy and EUS agreed in 37.5% of cases and EUS showed more extensive disease than endoscopy in 58% of cases. However, in comparison to the resection specimens, EUS still underestimated the tumor surface extension in 37.5% of cases; this was mainly in low grade malignant PGL. The depth of tumor infiltration was correctly determined on EUS compared to the resection specimens in 91.5% of cases. Sensitivity, specificity and accuracy of diagnosing lymph node metastases were 100%, 80% and 83%, respectively. We conclude that EUS is a useful pre-therapeutic staging tool for primary gastric lymphoma but there remain some problems in determining the longitudinal and circular tumor spread in order to accurately guide the extent of gastric resection.     

Lymph node dissection for T1 esophageal cancer

Proper mucosal cancer of esophagus of esophageal has no lymph node metastasis, and lymph node metastasis occurs when the tumor invades to muscularis mucosa. Submucosal cancer of esophagus has lymph node metastasis in the rate of 44.4% (40/90). The incidence and number of metastatic lymph node increase with the depth of invasion. Lymph node metastasis of esophageal cancer spreads widely to cervix, mediastinum and abdomen. It's same in submucosal cancer and first metastasis occurs also appears at everywhere from cervix to abdomen. There are high rate of lymph node metastasis in 101L, 105, 106rR, 106rL, 108, 110, 1, 2, 3, 7 lymph nodes. The cancer in upper thoracic esophagus has high rate of lymph node metastasis in cervix and upper mediastinum and lymph node metastasis of lower thoracic esophageal cancer is liable to appear in lower mediastinum and abdomen. Then the cancer in middle thoracic esophagus should be performed the lymph node dissection in cervix, mediastinum and abdomen, especially 101, 102m, 104, 105, 106r, 106t, 107, 108, 110, 1, 2, 3, 7 lymph nodes. On the other hand, cancers limited to proper mucosal layer should be treated with endoscopic mucosal resection. And its same as in the greater part of cancers invaded to muscularis mucosa and shallow layer of esophageal submucosa. The 5 year survival rate of T1 cancers of esophagus is 85.6%, which were performed surgical treatment.     

Evaluation of intraductal ultrasonography in the diagnosis of pancreatic cancer

An intraductal ultrasound (IDUS) probe which is inserted via the papilla into the main pancreatic duct (MPD) was evaluated in the diagnosis of 20 patients with pancreatic cancer. The examination was successfully performed with the probe in 17 of the patients (85%). Due to its high frequency (30 MHz) the probe only allowed visualization of the ductal wall and the immediate periductal vicinity (up to about 10 mm). In 15 of the 20 patients the tumors were surgically resected and IDUS scanning was also performed in vitro on the resection specimens, the results being compared to those of histopathological examination. Of these 15 patients, 13 were found to have ductal adenocarcinomas and all but one had been unequivocally diagnosed as having such by ultrasonography (US), computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasonography (EUS). IDUS showed an echorich area (corresponding to cancerous canaliculi on histopathological examination), surrounded by an echopoor area (abundant stroma). This pattern was classified as type I. In two patients with intraductal papillary carcinomas in whom a conclusive diagnosis was not established on US, CT, EUS or ERCP, IDUS showed tumorous tissue with an inhomogeneous echopattern outside (type II) or within (type III) the duct. These results show that IDUS offers valuable diagnostic information complementary to ERCP especially in cases of intraductal papillary tumors. Whether the high resolution imaging of the duct and the paraductal tissue can be used to differentiate between the different forms of pancreatic lesions (inflammation, neoplasms) has to be investigated further.     

Endoscopic ultrasonography with the ultrasonic esophagoprobe

Forty-one patients with either stenosing esophageal and cardia carcinoma (n = 27) or suspected tumor stenosis (n = 14), in whom conventional endosonography had failed, were evaluated with the ultrasonic esophagoprobe (blind probe). The main indication was locoregional staging of esophageal and cardia carcinomas, or restaging after radiotherapy or combined chemotherapy and radiotherapy. In 37% of the patients (10 of 27) an EUS T4 carcinoma was diagnosed, and in 63% (17/27) an EUS-T3 one. Regional lymph-node metastases were diagnosed in 96% of the cases. EUS restaging after nonsurgical palliative treatment detected tumor lesions in three of eight patients. Despite the fact that the imaging quality is still not satisfactory, our results suggest that the limitations of endoscopic ultrasonography (EUS) examination due to stenosing tumor growth can be overcome by the use of this ultrasonic esophagoprobe or similar instruments. Further technical developments may improve the resolution as well as the imaging quality in the celiac axis region.     

A model of rat''s urinary bladder tumor induced by subcutaneous injection of N-butyl-N-(4-hydroxybutyl)-nitrosamine]

Abscesses in the gastric wall are extremely rare. As the mucosa remains intact in most cases, clear differential diagnosis is required in order to distinguish the condition from the more frequent intramural mesenchymal tumors. Endoscopic ultrasonography provides a valuable tool for imaging intramural tumors, but this approach does not allow a definitive assessment of malignancy. We report about two patients with intramural abscesses in the gastric wall. Endosonography showing eccentric tumors from the gastric wall in the two patients. The endosonographic image was inhomogenous, the wall layer structure of the gastric wall was not preserved. A laparotomy was carried out on the first patient. In the second case, the diagnosis was easy, as pus was emptying from a small opening in the mucosa, which had already been detected at gastroscopy. Endoscopic intervention was carried out based on the endosonographic findings. In one patient, mucosa and submucosa were opened by a needle knife. These cases show that gastric wall abscesses do not have a typical endoscopic ultrasound appearance. However, endosonography is an essential method prior to endoscopic interventional therapy.     

Leiomyomata of the esophagus. An analysis of 838 cases

Review of the world literature to the end of 1971 has provided data on 838 cases of esophageal leiomyomata, including our own 19 surgically removed lesions. Although esophageal leiomyoma is the most common of the benign tumors of the esophagus, it is still rare compared with carcinoma. It occurs in more men than women, by a ratio of 1.9 to 1. Over 50% of the patients with leiomyoma of the esophagus are asymptomatic. Dysphagia and vague pain are the most frequent symptoms. Pyrosis is mentioned in the literature as present in 40% of the cases, but it is considered mainly as symptom of coexistent hiatal hernia. Diagnostic problems often arise, as the smooth muscle tumors may mimic mediastinal neoplasms, cysts, or even aneurysms, or complicate coexisting hiatal hernia and esophageal diverticulum. Operative management by transthoracic enucleation is the procedure of choice, although resection of the esophagaus may be required in few cases. Postoperative morbidity is minimal and results are excellent.     

Improving the treatment of colorectal cancer: the role of EUS

The two most important factors for determining the risk of local failure and overall prognosis in colorectal carcinoma are nodal status and the depth of tumor penetration into or through the bowel wall. These features have traditionally been determined pathologically because the clinical-staging accuracy of other imaging modalities such as computed tomography (CT) has not proven sufficiently predictive of surgical staging. However, endorectal or endoscopic ultrasonography (EUS) can be used to preoperatively evaluate nodal involvement with an accuracy of up to 86% (median: 80%) and depth of tumor penetration through the bowel wall with an accuracy of up to 97% (median: 85%) for effective clinical staging. This high staging accuracy is useful in managing colorectal cancer. Through clinical evaluation of the initial stage of colorectal cancer with EUS, a patient's risk of disease recurrence can best be determined and patients stratified for the most appropriate treatment. EUS can be used to select patients with lesions that can be treated with local excision or sphincter-sparing surgery, often combined with radiation therapy, in situations otherwise requiring an abdominoperineal resection. EUS can also be used to preoperatively identify patients with locally advanced or unresectable disease. Chemoradiation can then be given preoperatively, when it appears to be better tolerated and more effective than postoperative treatment. Unresectable tumors can often be downstaged sufficiently to allow their excision. In resectable disease, EUS can also identify patients at high risk for recurrence who would benefit from adjuvant chemoirradiation. EUS for precise staging or for earlier diagnosis of recurrence will further improve the clinical outcome of patients with colorectal tumors as significant advances both in surgical techniques and in combined chemotherapy/radiotherapy continue to be made and applied selectively in a stage-dependent manner.     

Expression of p21WAF1 predicts outcome of esophageal cancer patients treated by surgery alone or by combined therapy modalities

The p21WAF1 protein is an important regulator of the cell cycle. Its expression and prognostic significance were investigated immunohistochemically in samples of normal esophageal squamous epithelium (n = 10), severe squamous cell dysplasia (n = 20), carcinoma in situ (n = 14), permanent esophageal squamous cell carcinoma cell lines (n = 3), and invasive squamous cell carcinomas treated either by potentially curative resection (n = 172) or by combined modality therapy (radiochemotherapy +/- surgery; n = 38). Whereas p21WAF1 expression in the normal epithelium was restricted to a few cells adjacent to the basal cell layer, p21WAF1 overexpression was frequently found in preneoplasias and invasive carcinomas. Expression of p21WAF1 in invasive carcinomas was not correlated with tumor differentiation, pT category, or pN category. Among carcinomas treated by potential curative resection, univariate (P = 0.0025) and multivariate (P = 0.0081) survival analysis showed significant correlation of strong p21WAF1 expression (> or =50% p21WAF1-positive tumor cells) with poor overall survival. Univariate survival analysis (P = 0.0006) revealed the same prognostic influence in the group of patients treated by combined modality therapy. We conclude that overexpression of p21WAF1 protein is a frequent event in preneoplasias and neoplasias of the esophagus. Immunohistochemical examination of p21WAF1 expression may provide important prognostic information for decision-making in the treatment of patients with esophageal cancer.     

Endoscopic ultrasound for peripancreatic masses

BACKGROUND: Pancreatic neoplasms can be difficult to diagnose and stage preoperatively. Accurate staging allows the surgeon to select which patients can benefit from resection versus palliative therapy. Endoscopic ultrasound (EUS) with endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a diagnostic modality that provides visualization of peripancreatic tumors and their relationship to the surrounding structures as well as enabling cytologic diagnosis of the tumor and adjacent lymphadenopathy. METHODS: To define the role of this technique, a retrospective study was performed on 20 patients in the past year with peripancreatic tumors. RESULTS: Twelve men and 8 women ranging in age from 28 to 84 years (mean 67) were included in the study. Each patient underwent computed tomography followed by EUS-FNA, and the results were compared with operative findings or clinical course. The EUS-FNA findings included 10 pancreatic ductal carcinomas (50%), 5 pancreatitis (25%), 2 spindle cell neoplasms (10%), 1 cholangiocarcinoma (5%), 1 cystadenoma (5%), and 1 metastatic breast carcinoma (5%). Overall, EUS-FNA led to a significant change in the management of 12 patients (60%) through either diagnosing benign pathology, upstaging of the carcinoma, or determination that the peripancreatic mass represented a metastatic lesion. Five patients underwent resection of their peripancreatic tumors, and 3 patients had palliative procedures. Operative findings corresponded with EUS-FNA in all 8 patients. The 5 patients diagnosed with pancreatitis continued to be followed up for the possibility of a false negative FNA, but to date none have developed malignancy. CONCLUSIONS: EUS-FNA is a useful tool for the imaging and staging of peripancreatic tumors and will aid in the proper preoperative selection of patients who will benefit from resectional therapy.