Background: Endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) has become an important modality for identification of intra-abdominal masses. This study analyzed the accuracy of EUS-FNAB in a single medical center and explored factors related to positive diagnosis. Materials and methods: In total, 77 patients with EUS-FNAB were retrospectively reviewed from July 2016 to February 2020. "Atypical (tends to be neoplasm/malignancy)," "suspicious (first consider neoplasm/malignancy)," and "malignant" were defined as positive cytology. The final diagnoses were based on histopathologic examination. The positive rate of EUS-FNAB for the diagnosis of neoplasm and its associations with age, sex, target puncture mass size, liver function, tumor markers, albumin, hypertension, and diabetes were examined. Results: Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNAB cytologic diagnoses in all patients were 77.9% (60/77), 76.1% (54/71), 100%, 100%, and 26.1% (6/23), respectively. Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of EUS-FNAB cytologic diagnoses in the pancreas were 80.0% (48/60), 79.3% (46/58), 100%, 100%, and 14.3% (2/14), respectively. The results of EUS-FNAB in pancreatic masses showed that the level of CA19-9 was higher in the true positive group than in the false-negative group (p<0.05). There were no factors associated with the true positive cytologic diagnoses (p>0.05). Conclusions: Our single-medical center study showed that EUS-FNAB is an accurate diagnostic procedure for the evaluation of intra-abdominal masses. Further follow-up is required to explore factors associated with the true positive cytology.

Periampullary cancer includes cancer of the head and neck of the pancreas, cancer of the distal end of the bile duct, cancer of the ampulla of Vater, and cancer of the second part of the duodenum. Surgical resection is the only established potentially curative treatment for pancreatic and periampullary cancer. A considerable proportion of patients undergo unnecessary laparotomy because of underestimation of the extent of the cancer on computed tomography (CT) scanning. Other imaging methods such as magnetic resonance imaging (MRI), positron emission tomography (PET), PET-CT, and endoscopic ultrasound (EUS) have been used to detect local invasion or distant metastases not visualised on CT scanning which could prevent unnecessary laparotomy. No systematic review or meta-analysis has examined the role of different imaging modalities in assessing the resectability with curative intent in patients with pancreatic and periampullary cancer.

To determine the diagnostic accuracy of MRI, PET scan, and EUS performed as an add-on test or PET-CT as a replacement test to CT scanning in detecting curative resectability in pancreatic and periampullary cancer.

We searched MEDLINE, Embase, Science Citation Index Expanded, and Health Technology Assessment (HTA) databases up to 5 November 2015. Two review authors independently screened the references and selected the studies for inclusion. We also searched for articles related to the included studies by performing the "related search" function in MEDLINE (OvidSP) and Embase (OvidSP) and a "citing reference" search (by searching the articles that cite the included articles).

We included diagnostic accuracy studies of MRI, PET scan, PET-CT, and EUS in patients with potentially resectable pancreatic and periampullary cancer on CT scan. We accepted any criteria of resectability used in the studies. We included studies irrespective of language, publication status, or study design (prospective or retrospective). We excluded case-control studies.

Two review authors independently performed data extraction and quality assessment using the QUADAS-2 (quality assessment of diagnostic accuracy studies - 2) tool. Although we planned to use bivariate methods for analysis of sensitivities and specificities, we were able to fit only the univariate fixed-effect models for both sensitivity and specificity because of the paucity of data. We calculated the probability of unresectability in patients who had a positive index test (post-test probability of unresectability in people with a positive test result) and in those with negative index test (post-test probability of unresectability in people with a positive test result) using the mean probability of unresectability (pre-test probability) from the included studies and the positive and negative likelihood ratios derived from the model. The difference between the pre-test and post-test probabilities gave the overall added value of the index test compared to the standard practice of CT scan staging alone.

Only two studies (34 participants) met the inclusion criteria of this systematic review. Both studies evaluated the diagnostic test accuracy of EUS in assessing the resectability with curative intent in pancreatic cancers. There was low concerns about applicability for most domains in both studies. The overall risk of bias was low in one study and unclear or high in the second study. The mean probability of unresectable disease after CT scan across studies was 60.5% (that is 61 out of 100 patients who had resectable cancer after CT scan had unresectable disease on laparotomy). The summary estimate of sensitivity of EUS for unresectability was 0.87 (95% confidence interval (CI) 0.54 to 0.97) and the summary estimate of specificity for unresectability was 0.80 (95% CI 0.40 to 0.96). The positive likelihood ratio and negative likelihood ratio were 4.3 (95% CI 1.0 to 18.6) and 0.2 (95% CI 0.0 to 0.8) respectively. At the mean pre-test probability of 60.5%, the post-test probability of unresectable disease for people with a positive EUS (EUS indicating unresectability) was 86.9% (95% CI 60.9% to 96.6%) and the post-test probability of unresectable disease for people with a negative EUS (EUS indicating resectability) was 20.0% (5.1% to 53.7%). This means that 13% of people (95% CI 3% to 39%) with positive EUS have potentially resectable cancer and 20% (5% to 53%) of people with negative EUS have unresectable cancer.

Based on two small studies, there is significant uncertainty in the utility of EUS in people with pancreatic cancer found to have resectable disease on CT scan. No studies have assessed the utility of EUS in people with periampullary cancer.There is no evidence to suggest that it should be performed routinely in people with pancreatic cancer or periampullary cancer found to have resectable disease on CT scan.

Most extrahepatic bile-duct carcinomas are usually diagnosed when they are already in an advanced stage, which is the main reason for the poor prognosis of this tumor.

To examine the usefulness of MRCP followed by EUS in the early diagnosis of extrahepatic bile-duct carcinoma in the nonicteric stage.

This study included patients who were nonicteric, who had abnormal serum concentrations of alkaline phosphatase and gamma glutamyl transpeptidase, and whose common hepatic duct was more than 8 mm in diameter on abdominal US because of unknown reasons.

A single-center, prospective study.

An academic medical center.

The sensitivity and specificity of MRCP followed by EUS for the early diagnosis of extrahepatic bile duct carcinoma in the nonicteric stage.

A total of 142 patients who were nonicteric underwent prospective MRCP, and 26 of them underwent EUS. Ten patients (5 with stricture, 4 with filling defect, and 1 with no stricture or filling defect) had extrahepatic bile-duct carcinoma, including 5 patients with an incidentally diagnosed T1 stage tumor. The sensitivity and specificity of MRCP followed by EUS were 90% and 98%, respectively.

A single center and small number of patients.

MRCP followed by EUS was highly sensitive and specific for the early diagnosis of extrahepatic bile-duct carcinoma in the nonicteric stage, including T1 stage tumors. Filling defects, as well as stenosis in the bile duct, are important MRCP findings of T1 stage carcinoma.

To evaluate the diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for pancreatic solid tumors larger or smaller than 3 cm, and cystic lesions.

From January/1997 to December/2006, 611 patients with pancreatic tumors were subjected to EUS-FNA. The final diagnosis was obtained either by surgery (356 cases) or after a mean clinical follow-up of 11.8 mo in the remaining patients.

There were 405 solid tumors, 189 cystic lesions and 17 mixed. Pancreatic specimens for cytological assessment were successfully obtained by EUS-FNA in 595 (97.4%) cases. There were 352 (57.6%) malignancies and 259 (42.4%) benign tumors. Among the malignancies, pancreatic adenocarcinomas accounted for 67% of the lesions. Overall, the sensitivity, specificity, positive and negative predictive values, and accuracy of EUS-FNA were, respectively, 78.4%, 99.2%, 99.3%, 77.2% and 87.2%. Specifically for solid tumors, the same parameters for neoplasms larger and smaller than 3 cm were, respectively, 78.8% vs 82.4%, 100% vs 98.4%, 100% vs 99%, 54.8% vs 74.1% and 83.1% vs 87.8%. For cystic lesions, the values were, respectively, 72.2%, 99.3%, 97.5%, 91% and 92.2%.

EUS-FNA can be used to sample pancreatic tumors in most patients. Even though the negative predictive value is inadequate for large solid tumors, the results are rather good for small solid tumors, especially concerning the sensitivity, negative predictive value and diagnostic accuracy. Among all pancreatic lesions, EUS-FNA for cystic lesions can reveal the best negative predictive value and diagnostic accuracy, both higher than 90%.

To report the results of transduodenal excision (TDE) for tumors of the ampulla of Vater.

From 1998 to 2003, 10 patients underwent a transduodenal excision for presumed benign tumors of the ampulla of Vater. After resection, frozen sections were performed to ensure negative margins.

There was no operative mortality. A postoperative pancreatitis occurred in one patient. For nine patients the postoperative course was uneventful. The mean duration of hospital stay was 18 +/-11 days. The final pathology showed adenoma in 8 patients, an adenocarcinoma in one patient and inflammatory lesions in other one. With a mean follow-up of 20 months, endoscopy did not show any recurrence in patients with benign lesion. Patient with an invasive cancer developed recurrence.

Transduodenal excision is safe and effective treatment for benign ampullary tumors. TDE should be the operation of choice for patients with histologically-proven benign ampulloma, staged as uT1 by endoscopic ultrasound. This approach could reduce the rate of pancreaticaduodenoctomy performed for benign ampullomas.

Patients who present with signs and symptoms suggesting a pancreatic neoplasm typically undergo initial imaging with transabdominal ultrasound or CT. When a pancreatic mass or fullness is identified, it may represent an inflammatory mass, benign process, or malignancy. Endoscopic ultrasound (EUS) is performed commonly to further characterize the lesion, obtain a tissue diagnosis, and for staging. This article reviews the role of EUS for the diagnosis and staging of pancreatic tumors.

The early detection and accurate staging of pancreatic and ampullary cancer is of utmost importance for the achievement of surgical radical treatment. The aim of this study was to assess prospectively the role of endoscopic ultrasonography (EUS) in detection and staging of pancreatic and ampullary cancer, comparing its results to those obtained with spiral computed tomography (SCT).

Sixty-one patients with suspected pancreatic and ampullary tumors were included, 46 (75, 4%) of whom presented with obstructive jaundice. Patients underwent EUS and SCT within a 7-day period. Examiners were unaware of the previous imaging results, except conventional echography. Image interpretation was compared to surgical and histopathological findings.

Fifty-six (91, 8%) patients were surgically explored. Clinical follow-up and/or tissue diagnosis determined the correct diagnosis in the remaining five patients. Pancreatic cancer and ampullary cancer were observed in 29 (47, 6%) and 10 (16, 4%) patients, respectively. Chronic pancreatitis and choledocholithiasis were the most common diagnosis in patients with non-neoplastic disease. EUS was more effective than SCT for the definition of the final diagnosis in patients with obstructive jaundice (87.0 vs. 67.4%, p = 0.04). Both exams were equally effective for detecting pancreatic cancer but EUS predicted more accurately the involvement of portal-mesenteric axis by the tumor (87.0 vs. 67.4%, p = 0.04). EUS was particularly useful in the diagnosis of cancer of papilla of Vater.

In patients with pancreatic adenocarcinoma without unequivocal signs of distant metastatic disease, EUS is more accurate than SCT to predict venous involvement by the tumor. EUS is superior to SCT to detect ampullary adenocarcinoma. Both methods are equally ineffective to detect nodal involvement in pancreatic and ampullary cancer.

In single-institution studies, IORT at appropriate doses seems to safely improve local control in patients who have locally advanced pancreatic cancer, compared with historical controls. IORT also has been a component of adjuvant treatment programs that have led to excellent local control in resected patients. When considering the use of IORT, it is essential to have an understanding of the physical characteristics of the electron beam and how it can differ with the use of flat and beveled applicators. Although apparent improvement in local control with the use of IORT seems to have produced some improvement in median survival rates, high rates of distant failure continues to prevent a significant improvement in long-term survival. Because effective local control in patients with unresectable pancreatic cancer is a prerequisite to the development of curative therapies, the development of improved systemic therapies in patients with locally advanced pancreatic cancer will likely make local therapies such as the use of IORT even more important in the future.

Noninvasive imaging techniques, such as dynamic computed tomography (CT), magnetic resonance imaging and transabdominal ultrasonography are limited in their ability to detect hepatic lesions less than one cm. Intraoperative ultrasonography (IOUS) is currently the most sensitive modality for the detection of small hepatic lesions. However, IOUS is invasive requiring laparoscopy or formal laparotomy. We sought to evaluate the feasibility of using endoscopic ultrasonograhpy (EUS) for the detection and diagnosis of hepatic masses in patients with hepatocellular cancer (HCCA) and metastatic lesions (ML). We hypothesized that EUS could detect small (<1.0 cm) hepatic lesions undetectable by CT scan and could be used for biopsy of deep-seated hepatic lesions.

Consecutive patients referred for EUS with suspected liver lesions were evaluated between July 2000 and October 2001. All patients underwent EUS using an Olympus (EM30) radial echoendoscope. If liver lesions were confirmed and fine needle aspiration (FNA) was deemed necessary, a linear array scope was used and an FNA performed with a 22-gauge needle. Two passes were made for each lesion.

14 patients underwent evaluation with dynamic CT scans and EUS. In all 14 patients, EUS successfully identified hepatic lesions ranging in size from 0.3 cm to 14 cm (right lobe: n = 3, left lobe: n = 1, bilobar: n = 8). Moreover, EUS identified new or additional lesions in 28% (4 of 14) of the patients, all less than 0.5 cm in size (HCCA: n = 2, ML: n = 2), influencing the clinical management. In 2 of 14 patients EUS identified liver lesions, previously described as suspicious by CT scan, to be hemangiomas. Nine patients underwent EUS-guided FNA of hepatic lesions (deep seated: n = 3, superficial: n = 6). All FNA passes yielded adequate specimens (malignant: n = 8, benign: n = 1).

Our preliminary experience suggests that EUS is a feasible preoperative staging tool for liver masses suspected to be HCCA or metastatic lesions. EUS can detect small hepatic lesions previously undetected by dynamic CT scans. Furthermore, EUS-guided FNA can confirm additional HCCA liver lesions or liver metastases, in deep-seated locations, upstaging patients and changing clinical management.

Endoscopic ultrasound (EUS) provides detailed imaging of both intramural and extramural structures within the abdomen and mediastinum. However, EUS is limited in its ability to differentiate an inflammatory/reactive process from a malignancy. Fine-needle aspiration biopsy (FNAB), coupled with EUS, allows for the sampling of the target lesion under ultrasound guidance in real time. To better evaluate the clinical utility and efficiency of EUS-FNAB, a retrospective analysis of the first 103 EUS-FNABs performed at our institute was undertaken.

EUS-FNABs was performed in 80 patients with 103 lesions. Both air-dried and alcohol-fixed smears were prepared and stained with Diff-Quik (American Scientific Products, McGraw Park, IL) and Papanicolaou stains, respectively. In addition, ThinPrep slides (Cytyc, Boxborough, MA) and cell blocks, when additional material was available, were also prepared. Immunohistochemical stains were performed on cell blocks wherever required. Cytologic diagnoses were then correlated with the final diagnoses. The latter was based on histologic examination of biopsies/resected pathology materials (n = 54) and clinical follow up (n = 48). Follow-up information was not available for one lesion.

Of 103 EUS-FNABs, 42 FNABs were from the pancreas, 38 from the lymph nodes (10 mediastinal and 28 intraabdominal), 10 from the gastrointestinal tract, 7 from the liver, 4 from the adrenal gland, 1 from the biliary tract, and 1 from a retroperitoneal mass. The mean number of passes to obtain diagnostic materials was 3.3. Of 103 EUS-FNABs, 45, 9, 6, and 37 were reported as malignant, suspicious, atypical, and benign, respectively. Six FNABs were nondiagnostic. The authors did not encounter any false-positive cases. There were three false-negative cases (two pancreatic carcinomas and one gastrointestinal stromal tumor of the stomach). No complications were encountered. The sensitivity, specificity, and accuracy were 71%, 100%, and 81%, respectively. If the FNABs that were classified as suspicious were considered as malignant, the sensitivity, specificity, and accuracy were 86%, 100%, and 91%, respectively.

EUS-FNAB is a safe and accurate diagnostic procedure for the evaluation of intramural and extramural lesions of the gastrointestinal tract. In the majority of cases, it obviates the need for more invasive diagnostic procedures to obtain a tissue diagnosis.

The liver is a common site of metastases for various malignancies. EUS-guided fine needle aspiration (EUS-FNA) of liver masses has only been reported in small series from single centers.

A retrospective questionnaire was sent by e-mail to 130 EUS-FNA centers around the world regarding indications, complications, and findings of EUS-FNA of the liver.

Twenty-one centers reported 167 cases of EUS-FNA of the liver. A complication was reported in 6 (4%) of 167 cases including the following: death in 1 patient with an occluding biliary stent and biliary sepsis, bleeding (1), fever (2), and pain (2). EUS-FNA diagnosed malignancy in 23 of 26 (89%) cases after nondiagnostic fine needle aspiration under transabdominal US guidance. EUS localized an unrecognized primary tumor in 17 of 33 (52%) cases in which CT had demonstrated only liver metastases. EUS image characteristics were not predictive of malignant versus benign lesions.

EUS-guided FNA of the liver appears to be a safe procedure with a major complication rate of approximately 1%. EUS-FNA should be considered when a liver lesion is poorly accessible to US-, or CT-guided FNA should be considered when US- or CT-guided FNA fail to make a diagnosis, when a liver lesion(s) is detected (de novo) by EUS, and for investigation of possible upper GI primary tumors in the setting of liver metastases.

EUS has emerged as standard practice with respect to the diagnosis and staging of GI malignancies. Whether currently available resources are sufficient to meet the potential need for EUS is uncertain. This study examines the hypothetical demand for EUS in the United States.

EUS cases performed at 3 centers with well-established expertise in EUS in 1997 were retrospectively reviewed and trends were extrapolated to national cancer statistics. Indications for EUS fell into 3 categories: (1) diagnosis/staging of esophageal, gastric, pancreatic, or rectal cancers (established indications); (2) suspected GI malignancy (obligate "rule out"); and (3) "other" (emerging indications). Hypothetical total numbers of cases in which EUS could be performed in the United States were calculated taking into consideration the expected number of GI malignancies for which EUS would be appropriate (based on cancer statistics for 2000), the fraction unresectable by CT, the fraction of elderly nonsurgical candidates, proportionate "rule out" cases, as well as "other" emerging indications.

The calculated hypothetical number of cases (United States) in which EUS would be indicated is 79,568 per year (10,287 esophagus, 10,666 stomach, 23,069 pancreas, and 35,546 rectal). If "other" indications remained constant at 12%, there would potentially be 89,116 EUS procedures performed per year, with a conservative estimate of 79,572 per year.

This model suggests that currently available EUS resources are not sufficient to meet hypothetical demand. Future considerations include the number of endoscopy units in which EUS is performed, the capacity of individual units, and the implications for training programs in the United States.

Ductal carcinoma of the pancreas remains a challenging problem for gastrointestinal surgeons. Significant progress has been made in diagnosis, preoperative staging, and safety of surgery; however, long-term survival after resection is unusual, and cure is rare. That said, the authors maintain their aggressive posture regarding this disease, recognizing that resection offers the only potential for cure. The authors' approach such patients in the most efficient and least invasive manner possible, relying primarily on triple phase helical abdominal CT for clinical diagnosis and staging, reserving ERCP and EUS for diagnostic dilemmas. In fit candidates with potentially resectable lesions, the authors eschew pre- or intraoperative biopsy, angiography, or endoscopic stenting and use preliminary limited staging laparoscopy selectively. Surgical palliation is chosen for fit patients who, at exploration for potentially curative resection, are found to have occult distant metastases or locally unresectable disease. Radical pancreatoduodenectomy can be performed with a mortality rate of 3% or less, and although morbidity remains significant, most can be managed with conservative measures. Quality of life after pancreatoduodenectomy is good and, if not, is generally a manifestation of recurrence rather than physiologic alterations inherent to the procedure. Adjuvant chemoradiation is standard therapy after resection, recommended for those with locally unresectable disease but used selectively for those with distant metastasis. Survival after potentially curative resection has remained disappointing. Whether extended lymphadenectomy or neoadjuvant chemoradiation improves survival has not been determined. Clearly, methods for earlier diagnosis of pancreatic cancer and more effective adjuvant therapies are sorely needed.

EUS-guided fine-needle aspiration (EUS-FNA) permits both morphologic and cytologic analysis of lesions within or adjacent to the GI tract. Despite increasing use of this technique, the safety and overall complication rates remain poorly defined.

During a period of 20 months, 322 consecutive patients underwent EUS-FNA in 2 centers. All procedures were performed with the patients under general anesthesia. All complications (including local complications resulting from endoscopy/aspiration or clinical complications after the procedure) were evaluated. Potential risk factors for the development of complications were also analyzed including site and nature of the lesion, presence of portal hypertension, and number of needle passes.

A total of 345 lesions were aspirated in 322 patients. EUS-FNA involved the pancreas in 248 cases. Pancreatic lesions included solid (134) and cystic (114) types, which required a mean of 2.5 and 1.4 needle passes, respectively. Complications were observed in 4 (1.2%) patients after aspiration of pancreatic cystic lesions (acute pancreatitis, n = 3; aspiration pneumonia, n = 1) and all cases of pancreatitis resulted from FNA of lesions in the head/uncinate process. No complications resulted from FNA of solid pancreatic lesions. Complications were not observed after FNA of lymph nodes (n = 62) and one case of aspiration pneumonia was observed after FNA of a stromal tumor. EUS-FNA was performed without complication in 16 patients (5%) with portal hypertension. The number of needle passes was not predictive of complications.

Because the overall risk of complications from EUS-FNA was relatively low (1.6%) with no severe or fatal incidents and although the risk appears slightly higher than that for standard EUS alone, the safety of EUS-FNA appears acceptable based on this analysis from an experienced center.

'Idiopathic' pancreatitis may be diagnosed when gallstones are excluded by transabdominal ultrasonography and less common causes are not implicated by history or other investigations. Transabdominal ultrasonography may not, however, detect small stones responsible for acute pancreatitis. The aim of this study was to determine if endoscopic ultrasonography (EUS) is able to identify undetected gallstones in cases of 'idiopathic' pancreatitis.

Consecutive patients presenting with 'idiopathic' pancreatitis were assessed using EUS for the presence of gallstones or other potential causes of the attack. A control group was also imaged.

Forty-four patients with 'idiopathic' pancreatitis were assessed. Ten had suffered earlier attacks of pancreatitis before this study. EUS revealed proven pathology in 18 patients. Unconfirmed pathology was evident in 14. No abnormality was seen in only nine patients. EUS failed in one patient and there were two possible false-positive results.

EUS is able to identify significant pathology in patients in whom a diagnosis of 'idiopathic' pancreatitis has been made following standard investigations. Patients with untreated gallstones are at risk of recurrent attacks. Idiopathic pancreatitis should not be diagnosed unless EUS has been performed.

Endoscopic ultrasonography (EUS) represents a major advance in endoscopic imaging. The usefulness and effectiveness of EUS have been established during the past few years. However, endosonography using dedicated echoendoscopes (7.5/12 MHz) has some serious drawbacks, as follows: 1) Combining endoscopy and ultrasonography in one instrument increases the diameter of such echoendoscopes (12-13 mm); 2) Because of the large diameter, complete passage of severe strictures is often not possible and, for examination of the pancreatobiliary duct system, is not feasible at all; 3) Image quality and resolution for small lesions is not always satisfactory; and 4) Conventional endosonography requires a second examination separate from the previous routine endoscopy. Recently developed ultrasonographic miniprobes (diameters about 2 mm; frequencies 12-20 MHz) can be passed through the working channel of standard endoscopes to provide high frequency ultrasound images. These miniprobes might overcome some of the above-mentioned drawbacks and contribute to patients' security and convenience. Moreover, in various diseases of the GI tract and the pancreatobiliary duct system, diagnostic accuracy of miniprobe ultrasonography has been shown to be even superior to that of EUS. In summary, miniprobe ultrasonography seems to be a promising tool in the armamentarium of gastroenterological diagnostics.

This article reviews recent developments in pancreatic cancer research and offers a multispecialty perspective on the diagnosis and management of this challenging disease. Current findings in the molecular biology of the disease and their implications for management are examined, as well as development in diagnostic techniques, including helical computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangio-pancreatography (MRCP), and, particularly, endoscopic ultrasound-guided fine-needle aspiration. Surgical management, the role of adjuvant/neoadjuvant chemoradiation therapy, and the critical importance of accurate preoperative imaging are also addressed in this review. Palliative techniques, including endoscopic stenting for malignant obstructive jaundice and chemotherapy for locally advanced and metastatic disease, are discussed, and results of recent clinical trials in pancreatic cancer are summarized. Finally, future directions for research are identified.

This literature review and the recommendations therein were prepared for the American Gastroenterological Association Clinical Practice and Practice Economics Committee. The paper was approved by the Committee in March 1999 and by the AGA Governing Board in May 1999.

Endoscopic ultrasonography (EUS) represents a major advance in endoscopic imaging. Usefulness and effectiveness of EUS have been established during the past few years. However, endosonography using dedicated echoendoscopes (7.5/12 MHz) has some serious drawbacks: (1) combining endoscopy and ultrasonography in one instrument increases the diameter of such echoendoscopes (13 mm); (2) as a result of the large diameter insertion into the pancreato-biliary duct system is not feasible at all; (3) image quality and resolution for small lesions is not always satisfactory; and (4) conventional endosonography needs a second examination separate from the previous routine endoscopy. Recently developed ultrasonographic miniprobes (diameters about 2 mm; frequencies 12-20 MHz) can be passed through the working channel of standard endoscopes to provide high-frequency ultrasound images. These miniprobes might overcome some of the above mentioned drawbacks and contribute to patients' security and convenience. Moreover, in various diseases of the pancreato-biliary duct system diagnostic accuracy of miniprobe ultrasonography has been shown to be superior to that of EUS. In summary, miniprobe ultrasonography appears to be a promising addition to the armamentarium of gastroenterologic diagnostics.

Endoscopic ultrasonography (EUS) is not traditionally thought to be clinically applicable in liver imaging. EUS-guided fine-needle aspiration of the liver has not been well described.

A prospective study was conducted in which 574 consecutive patients with a history or suspicion of gastrointestinal or pulmonary malignant tumor undergoing upper EUS examinations underwent EUS evaluation of the liver. Fourteen (2.4%) patients were found to have focal liver lesions and underwent EUS-guided fine-needle aspiration.

The median largest diameter of the liver lesions was 1.1 cm (range 0.8 to 5.2 cm). The mean number of passes was 2.0 (range 1 to 5 passes). All fine-needle passes yielded an adequate specimen. One of the 14 patients underwent EUS-guided fine-needle aspiration of 2 liver lesions. Fourteen of the 15 liver lesions sampled by means of EUS-guided fine-needle aspiration were malignant and one was benign. Before EUS, computed tomography (CT) depicted liver lesions in only 3 of 14 (21%) patients. Seven of 14 patients had a known cancer diagnosis. For the other 7, the initial diagnosis of cancer was made by means of EUS-guided fine-needle aspiration of the liver. There were no immediate or late complications.

EUS can detect small focal liver lesions that are not detected at CT. Findings of EUS-guided fine-needle aspiration can confirm a cytologic diagnosis of liver metastasis and establish a definitive M stage that may change clinical management.

Intraductal ultrasonography (IDUS) was performed on 22 patients with extrahepatic bile duct cancer, using the percutaneous transhepatic approach. Intraductal ultrasonography images of the proximal invasion of the bile duct cancer were defined. In addition, three patients were examined through the peroral approach, to try to diagnose whether or not the cancer invaded to the bifurcation of the hepatic duct. Intraductal ultrasonography images obtained through the percutaneous approach could be classified into three patterns, types 1, 2 and 3, according to the features of the interior surface of the bile duct and the thickness of the bile duct wall. Type 1 images, which did not show protrusions into the bile duct lumen and had a bile duct wall of even thickness, were not likely to show bile duct cancer. Type 2 images showed protrusions of the tumour into the bile duct lumen and the surfaces of the protrusions were irregular. Type 3 images showed single or multiple low echoic papillary masses in the bile duct. Using the peroral technique, we considered all three cases to be type 1 and could diagnose that cancer had not invaded to the bifurcation of the hepatic ducts. From the results of this study, we suggest that proximal invasion of extrahepatic bile duct cancer can be diagnosed using IDUS.

Open laparotomy has traditionally been required to stage hepatobiliary and pancreatic (HBP) cancers accurately. For unresectable patients, costs and morbidity have been high. Today, laparoscopy alone or combined with laparoscopic ultrasonography (LUS) is being examined for its value in defining the extent of malignancy.

We have analyzed the effect of routine implementation of this new staging technique in our HBP center. Staging laparoscopy (SL) with LUS was performed in 50 consecutive patients with HBP malignancies. All patients were considered to have resectable tumors as determined by traditional preoperative staging modalities. Primary tumors were located in the liver (n = 7), biliary tract (n = 11), or pancreas (n = 32). An average of 2.7 preoperative studies per patient were performed prior to SL-LUS.

Staging laparoscopy with laparoscopic ultrasonography predicted resectable tumors in 28 patients (56%). At laparotomy, 26 of 28 were actually resectable: the false-negative rate was 4%. Staging laparoscopy with laparoscopic ultrasonography indicated unresectability in 22 patients (44%). Staging laparoscopy alone demonstrated previously unrecognized occult metastases in 11 patients (22%). In 11 other patients (22%) in whom SL alone was negative, LUS established unresectability from vascular invasion (n = 5), lymph node metastases (n = 5), or intraparenchymal hepatic tumor (n = 1). All cases of unresectability due to vascular invasion were validated by laparotomy. Five of six lymph node or hepatic metastases were proved histologically by LUS-guided needle biopsy rather than laparotomy.

Unnecessary laparotomy can be safely avoided by SL-LUS in many patients with HPB malignancies, reducing costs and morbidity.

Endoscopic ultrasound (EUS) guided fine-needle aspiration (FNA) of pancreatic lesions is being increasingly used. Our aim was to determine the safety, accuracy, and clinical utility of EUS-guided FNA in both the diagnosis and staging of pancreatic cancer.

Forty-four patients (24 men/20 women) had EUS-guided FNA of pancreatic lesions (39 head/neck, 5 body, 3 tail) and/or associated lymph nodes. The mean age was 61 (range, 28 to 88 years). The indication for EUS-guided FNA was a pancreatic lesion seen initially on CT (39%), ERCP (43%), or EUS (18%). Follow-up data were collected on all patients for mean of 14.5 months (range 1 to 33 months).

CT detected only 15 of 61 (25%) focal lesions seen by EUS, Adequate specimens were obtained by EUS-guided FNA in 44 of 47 (94%) pancreatic lesions and 14 of 14 (100%) associated lymph nodes (overall adequacy was 95%). Of the 46 lesions in which specimens were adequate and a final diagnosis was available (32 malignant, 14 benign), EUS-guided FNA had a sensitivity of 92%, specificity of 100%, and diagnostic accuracy of 95% for pancreatic lesions and 83%, 100%, and 88% for lymph nodes, respectively. Six percent of pancreatic cases had inadequate specimens and, if included, lowered the sensitivity to 83%, specificity to 80%, and diagnostic accuracy to 88% for pancreatic lesions. In 3 patients with enlarged celiac nodes on EUS, EUS-guided FNA was able to make a tissue diagnosis of metastasis, which changed the preoperative staging and precluded surgery. EUS in combination with EUS-guided FNA precluded surgery in 12 of 44 (27%) and may have precluded surgery in an additional 6 of 44 (14%). EUS-guided FNA avoided the need for further diagnostic tests, thus expediting therapy in a total of 25 (57%) patients and influenced clinical decisions in 30 of 44 (68%) patients. The estimated cost savings based on surgeries avoided was approximately $3300 per patient. There was only one complication (2%), a post-FNA fever.

EUS-guided FNA of the pancreas appears to be a safe and effective method that increases both the diagnostic and staging capability of EUS in pancreatic cancer. The clinical impact of EUS-guided FNA includes avoiding surgery and additional imaging studies with a substantial cost savings.

Endoscopic ultrasound (EUS) is useful in the detection of pancreatic carcinoma. One of its major limitations is the lack of specificity for malignancy, both for the primary tumor and for associated lymph nodes due to its inability to distinguish malignant infiltration from benign inflammation. EUS-guided fine needle aspiration (FNA) has now been developed, which allows for a tissue diagnosis of the primary tumor as well as lymph nodes, liver metastasis, and peritoneal/pleural fluid. The addition of EUS-guided FNA, with the specificity of a tissue diagnosis, to the high sensitivity and vascular assessment of EUS alone makes this the modality of choice for the diagnosis and staging of pancreatic carcinoma. The results of preliminary studies along with discussion regarding the technique, safety, cytologic adequacy, diagnostic accuracy, clinical utility, and future trends of EUS-guided FNA in pancreatic tumors are presented.

The accuracy of endoscopic ultrasonography (EUS) for diagnosis of pancreatic cancers was evaluated in consecutive 232 patients with possible pancreatic cancer, and that for assessment of their locoregional spread was evaluated in 28 patients with pancreatic cancer subjected to pancreatectomy, in comparison with the accuracies of transabdominal ultrasonography (US) and computed tomography (CT). EUS was found to be significantly more accurate than US or CT and was especially useful for detecting small pancreatic cancers of less than 2 cm in diameter. With EUS, pancreatic cancers could be detected as a hypoechoic mass with a relatively unclear margin and irregular internal echoes. EUS was also more sensitive than CT and US for detecting venous and gastric invasions: it was more useful for detecting direct invasion of pancreatic cancers when the tumors were less than 3 cm in diameter. These findings indicate that EUS is an accurate method for diagnosis of pancreatic cancer and assessment of their locoregional spread and is particularly useful for detecting small tumors.

Thirty-eight consecutive patients underwent endoscopic ultrasound-guided fine-needle aspiration. Of 46 lesions, 34 were extraluminal (12 pancreatic masses, 8 periesophageal nodes, 6 celiac nodes, 2 pericolonic masses, 1 mediastinal mass, 1 perigastric mass, 1 liver, 1 periduodenal node, 1 perirectal mass, 1 perirectal node) and 12 were submucosal (8 gastric, 3 duodenal, 1 esophageal). One hundred sixty-three passes were made, with an average of 3.5 passes per lesion and 4.3 passes per patient (range, 1 to 8). Adequate specimens were obtained from 91% of targeted lesions. The overall diagnostic accuracy was 87%. In patients with malignant lesions, sensitivity was 91% and specificity 100%. Celiac nodes were successfully sampled and diagnostic in 5 of 6 (83%) patients. No complications occurred. Using this technique, an initial tissue diagnosis of malignancy was made in 66% of cancer patients without a previous diagnosis and the preoperative stage was changed in 44% of cancer patients. The additional information gained by this modality directly influenced the decision not to perform surgery in 26% of patients with a primary malignancy. Endoscopic ultrasound-guided fine-needle aspiration is feasible and can be safely used to evaluate submucosal and extraluminal lesions in both the upper and lower gastrointestinal tract with a high degree of diagnostic accuracy.