Endoscopic ultrasound in pancreatic disease--its influence on surgical decision-making. An update 2008

Tumor growth rate of pancreatic serous cystadenomas: Endosonographic follow-up with volume measurement to predict cyst enlargement

BACKGROUND

Serous cystadenomas are benign lesions of the pancreas. Usually they are diagnosed incidentally on cross-sectional imaging studies. Endosonography is a valuable tool in the diagnosis and follow-up of these cystic lesions. Given its benign nature, surgical resection is advised only in symptomatic patients. The interval and length of surveillance is not well established.

METHODS

A retrospective single center study was done. All the patients with a pancreatic serous cystadenoma sent for an endosonographic evaluation, between December 2008 and December 2015 were included. The lesions were follow-up endosonographically at least once, in a 12 months interval. Volume was measured with the formula π/6 × (d1 x d1 x d2). Two groups were evaluated: patients with a volume under 10 mL (Group 1) and those with a volume of 10 mL or more at presentation (Group 2). Growth rate between these two groups was compared.

RESULTS

Thirty-one patients were analyzed, with a mean age of 58.2 years. Patients were mainly women (87%). Twenty-four patients in Group 1 had a mean enlargement of 0.67 ml per year, whereas patients in Group 2 had a mean enlargement of 9.8 ml per year. The growth rate difference between these two groups was statistically significant (p = 0.0001).

CONCLUSION

Asymptomatic patients with pancreatic serous cystadenomas should be follow-up for enlargement. Small volume lesions have a low risk of enlargement compared with high volume and macrocystic serous cystadenomas. Volume at presentation is a feature to analyze when defining surveillance interval.

Current perspectives on pancreatic serous cystic neoplasms: Diagnosis, management and beyond

Pancreatic cystic neoplasms have been increasingly recognized recently. Comprising about 16% of all resected pancreatic cystic neoplasms, serous cystic neoplasms are uncommon benign lesions that are usually asymptomatic and found incidentally. Despite overall low risk of malignancy, these pancreatic cysts still generate anxiety, leading to intensive medical investigations with considerable financial cost to health care systems. This review discusses the general background of serous cystic neoplasms, including epidemiology and clinical characteristics, and provides an updated overview of diagnostic approaches based on clinical features, relevant imaging studies and new findings that are being discovered pertaining to diagnostic evaluation. We also concisely discuss and propose management strategies for better quality of life.

Imaging tests for accurate diagnosis of acute biliary pancreatitis

Gallstones represent the most frequent aetiology of acute pancreatitis in many statistics all over the world, estimated between 40%-60%. Accurate diagnosis of acute biliary pancreatitis (ABP) is of outmost importance because clearance of lithiasis [gallbladder and common bile duct (CBD)] rules out recurrences. Confirmation of biliary lithiasis is done by imaging. The sensitivity of the ultrasonography (US) in the detection of gallstones is over 95% in uncomplicated cases, but in ABP, sensitivity for gallstone detection is lower, being less than 80% due to the ileus and bowel distension. Sensitivity of transabdominal ultrasonography (TUS) for choledocolithiasis varies between 50%-80%, but the specificity is high, reaching 95%. Diameter of the bile duct may be orientative for diagnosis. Endoscopic ultrasonography (EUS) seems to be a more effective tool to diagnose ABP rather than endoscopic retrograde cholangiopancreatography (ERCP), which should be performed only for therapeutic purposes. As the sensitivity and specificity of computerized tomography are lower as compared to state-of-the-art magnetic resonance cholangiopancreatography (MRCP) or EUS, especially for small stones and small diameter of CBD, the later techniques are nowadays preferred for the evaluation of ABP patients. ERCP has the highest accuracy for the diagnosis of choledocholithiasis and is used as a reference standard in many studies, especially after sphincterotomy and balloon extraction of CBD stones. Laparoscopic ultrasonography is a useful tool for the intraoperative diagnosis of choledocholithiasis. Routine exploration of the CBD in cases of patients scheduled for cholecystectomy after an attack of ABP was not proven useful. A significant rate of the so-called idiopathic pancreatitis is actually caused by microlithiasis and/or biliary sludge. In conclusion, the general algorithm for CBD stone detection starts with anamnesis, serum biochemistry and then TUS, followed by EUS or MRCP. In the end, bile duct microscopic analysis may be performed by bile harvested during ERCP in case of recurrent attacks of ABP and these should be followed by laparoscopic cholecystectomy.

Pancreatitis-imaging approach

Pancreatitis is defined as the inflammation of the pancreas and considered the most common pancreatic disease in children and adults. Imaging plays a significant role in the diagnosis, severity assessment, recognition of complications and guiding therapeutic interventions. In the setting of pancreatitis, wider availability and good image quality make multi-detector contrast-enhanced computed tomography (MD-CECT) the most used imaging technique. However, magnetic resonance imaging (MRI) offers diagnostic capabilities similar to those of CT, with additional intrinsic advantages including lack of ionizing radiation and exquisite soft tissue characterization. This article reviews the proposed definitions of revised Atlanta classification for acute pancreatitis, illustrates a wide range of morphologic pancreatic parenchymal and associated peripancreatic changes for different types of acute pancreatitis. It also describes the spectrum of early and late chronic pancreatitis imaging findings and illustrates some of the less common types of chronic pancreatitis, with special emphasis on the role of CT and MRI.

Endoscopic ultrasound and pancreatic applications: what the radiologist needs to know

As the technology has improved, endoscopic ultrasound (EUS) has taken on an important role in the diagnosis of a number of different neoplastic and non-neoplastic pancreatic diseases. EUS can provide high-resolution images with subtle anatomic detail, and has also taken on an important role in the targeted biopsy of the pancreas and adjacent structures. This review seeks to familiarize radiologists with the role of EUS in the diagnosis of chronic and autoimmune pancreatitis, solid pancreatic masses, and cystic pancreatic neoplasms.

The revised Atlanta classification of acute pancreatitis: its importance for the radiologist and its effect on treatment

An international working group has modified the Atlanta classification for acute pancreatitis to update the terminology and provide simple functional clinical and morphologic classifications. The modifications (a) address the clinical course and severity of disease, (b) divide acute pancreatitis into interstitial edematous pancreatitis and necrotizing pancreatitis, (c) distinguish an early phase (1st week) and a late phase (after the 1st week), and (d) emphasize systemic inflammatory response syndrome and multisystem organ failure. In the 1st week, only clinical parameters are important for treatment planning. After the 1st week, morphologic criteria defined on the basis of computed tomographic findings are combined with clinical parameters to help determine care. This revised classification introduces new terminology for pancreatic fluid collections. Depending on presence or absence of necrosis, acute collections in the first 4 weeks are called acute necrotic collections or acute peripancreatic fluid collections. Once an enhancing capsule develops, persistent acute peripancreatic fluid collections are referred to as pseudocysts; and acute necrotic collections, as walled-off necroses. All can be sterile or infected. Terms such as pancreatic abscess and intrapancreatic pseudocyst have been abandoned. The goal is for radiologists, gastroenterologists, surgeons, and pathologists to use the revised classifications to standardize imaging terminology to facilitate treatment planning and enable precise comparison of results among different departments and institutions.

EUS-guided FNA of solid pancreas tumors

Although endoscopic ultrasonography (EUS) is considered superior to MRI and CT in detecting pancreatic masses, it is the ability to target and place a needle into suspicious lesions that has made EUS indispensible in the evaluation of patients with solid pancreatic tumors. Endoscopic ultrasound-guided-fine-needle aspiration (EUS-FNA) is an accurate and safe technique to confirm the diagnosis of pancreatic cancer. EUS-FNA is now the principal technique applied to obtain the diagnosis of malignancy. We have designed this article to address a number of the key technical aspects of EUS-FNA of solid pancreatic masses.

Pancreato-biliary malignancy diagnosed by endoscopic ultrasonography in absence of a mass lesion on transabdominal imaging: prevalence and predictors

BACKGROUND AND AIMS

Pancreatic adenocarcinoma is the fourth leading cause of cancer-related death in the United States. Pancreatic cancer is diagnosed in some patients by endoscopic ultrasonography (EUS) even in the absence of an obvious mass lesion on transabdominal imaging studies. The purpose of this study was to estimate the prevalence of PBM on EUS-FNA in patients with no obvious mass on transabdominal imaging and identify possible predictors of PBM in this cohort of patients.

METHODS

Three hundred and twenty-six patients (219 female; mean age: 57) with no obvious neoplastic lesion on trans-abdominal imaging underwent EUS. Demographic data, indication of EUS, history of weight loss, smoking, alcohol use, diabetes, cholecystectomy status, CT and USG findings, and liver function tests (LFTs) were reviewed.

RESULTS

Thirty patients (9%) were diagnosed with a PBM by EUS-FNA (27 pancreatic adenocarcinoma, three ampullary adenocarcinoma). The mean age of patients diagnosed with PBM was significantly (P < 0.01) higher than controls. The mean size of the tumor was 2.8 cm (range: 0.9-7 cm). Male gender, presence of jaundice, abnormal LFTs, weight loss, and nonspecific trans-abdominal imaging results such as dilated common bile duct (CBD), and abnormal appearing pancreas predicted the presence (P < 0.05) of PBM, whereas patients with previous cholecystectomy and abdominal pain were less likely to have this diagnosis.

CONCLUSIONS

Normal trans-abdominal imaging does not completely exclude the presence of PBM. Nonspecific pancreatic abnormalities and CBD dilation on trans-abdominal imaging, with jaundice, abnormal LFTs, weight loss, and lack of abdominal pain are predictors of PBM.

Primary pancreatic cystic neoplasms revisited. Part III. Intraductal papillary mucinous neoplasms

Intraductal papillary mucinous neoplasms (IPMNs) represent about 25% of all primary pancreatic cystic neoplasms and are increasingly recognized during the last two decades. They are characterized by intraductal proliferation of neoplastic mucinous cells forming papillary projections into the pancreatic ductal system, which is typically dilated and contains globules of mucus. IPMNs may be multifocal and have malignant potential. Modern imaging is essential in establishing preoperative diagnosis and in differentiating different subtypes of IPMNs (i.e., main-duct vs. branch-type disease). Endoscopic retrograde or magnetic resonance cholangiopancreatography accurately delineate the morphologic changes of the pancreatic ductal system. Endoscopic ultrasonography (usually used in conjunction with image-guided FNA and analysis of the aspirated material) is commonly used for differential diagnosis of IPMNs from other pancreatic cystic lesions. Surgical resection (usually anatomic pancreatectomy, depending on the location of the disease) is the treatment of choice. Total pancreatectomy may occasionally be required in selected patients, but is associated with formidable long-term morbidity. A conservative approach has recently been proposed for carefully selected patients with branch-duct IPMNs. Recurrences following surgical resection can be observed, especially in patients with multifocal disease or in the presence of underlying malignancy.

Impact of CT-based diagnostic imaging on management and outcome of nonfunctioning pancreatic tumors

BACKGROUND

Sporadic malignant non-functioning pancreatic endocrine tumors (NF-PETs) are an important subset of pancreatic neoplasms. The aim of this study was to assess the impact of improved imaging on these features in a tertiary referral centre within a 20-year follow-up.

PATIENTS AND METHODS

From 1988 to 2009, 51 patients were treated for sporadic malignant NF-PETs. Forty-one patients who underwent tumor resection were retrospectively attributed according to the date of the initial diagnosis, group 1: 1988-1999 vs. group 2: 2000-2009.

RESULTS

Cross-sectional imaging led to positive prediction of NF-PETs in all patients. Curative resection was achieved in 76%. Synchronous metastases were present in 56% with a positive prediction of 43%. In group 1, the mean reported CT-determined tumor size was 56 vs. 54 mm in group 2 (p = 0.89). Synchronous metastases were present in 61% in group 1 vs. 57% (p = 0.99) in group 2. Metachronous metastases were recorded in 39% in group 1 vs. 43% (p = 0.84) in group 2. The mean interval from initial resection to diagnosis of metastatic disease was significantly shorter (p = 0.01) in patients from group 1 (14 vs. 61 months). Cumulative 5- and 10-year survival rates were 77% and 72% in group 1 vs. a 5-year survival rate of 66% in group 2.

CONCLUSION

So far, improved CT-based imaging has no impact on earlier detection of initial synchronous metastases in sporadic malignant NF-PETs, while metachronous metastases are detected earlier.

Primary pancreatic cystic neoplasms revisited: part II. Mucinous cystic neoplasms

Mucinous cystic neoplasms (MCNs) of the pancreas represent one of the most common primary pancreatic cystic neoplasms, accounting for approximately half of these cases. MCNs are observed almost exclusively in women, and most commonly are located in the body/tail of the pancreas. In contrast to SCNs, MCNs have malignant potential. Proliferative changes (hyperplasia with or without atypia, borderline changes, non-invasive or carcinomas in-situ, and invasive carcinomas) can often be observed within the same neoplasm. Several risk factors for the presence of underlying malignancy within an MCN have recently been recognized. Cross-sectional imaging is of key importance for the diagnostic evaluation of patients with a cystic pancreatic lesion. Cyst fluid examination (cytology, biochemical/genetic analysis) is possible by using fine needle aspiration of the MCN, usually under endoscopic guidance, and may provide useful information for the differential diagnosis. Since MCNs have malignant potential, surgical resection is the treatment of choice.

Primary pancreatic cystic neoplasms revisited. Part I: serous cystic neoplasms

Primary pancreatic cystic neoplasms have been recognized increasingly during the two recent decades and include mainly serous cystic neoplasms, mucinous cystic neoplasms, and intraductal papillary mucinous neoplasms. Serous cystic neoplasms represent about 30% of all cystic neoplasms of the pancreas and are characterized by their microcystic appearance (on imaging, macroscopically, and microscopically) and their benign biologic behavior. Modern diagnostic methodology allows the preoperative diagnosis with an acceptable accuracy. Currently, indications for resection of serous cystic neoplasms of the pancreas include the presence of symptoms, size > 4 cm (because these 'large' neoplasms have a more rapid growth rate and probably will soon become symptomatic), and any uncertainty about the diagnosis of a serous versus a mucinous cystic neoplasm. Resection should also be considered for lesions in the body/tail of the pancreas. Conservative treatment is a reasonable option in selected patients (for example in the presence of small, asymptomatic lesions in the pancreatic head, especially in the frail or elderly patient).

Role of pancreatic endoscopic ultrasonography in 2010

Endoscopic ultrasonography (EUS) was introduced 25 years ago aiming at better visualization of the pancreas compared to transabdominal ultrasonography. This update discusses the current evidence in 2010 concerning the role of EUS in the clinical management of patients with pancreatic disease. Major indications of EUS are: (1) Detection of common bile duct stones (e.g. in acute pancreatitis); (2) Detection of small exo- and endocrine pancreatic tumours; and (3) Performance of fine needle aspiration in pancreatic masses depending on therapeutic consequences. EUS seems to be less useful in cases of chronic pancreatitis and cystic pancreatic lesions. Moreover the constant improvement of computed tomography has limited the role of EUS in pancreatic cancer staging. On the other hand, new therapeutic options are available due to EUS, such as pancreatic cyst drainage and celiac plexus neurolysis, offering a new field in which new techniques may arise. So the main goal of this review is to determine the exact role of EUS in a number of pancreatic and biliary diseases.

Contrast enhanced endoscopic ultrasound: More than just a fancy Doppler

Contrast enhanced endoscopic ultrasound (CEUS) is a new modality that takes advantage of vascular structure and blood flow to distinguish different clinical entities. Contrast agents are microbubbles that oscillate when exposed to ultrasonographic waves resulting in characteristic acoustic signals that are then converted to colour images. This permits exquisite imaging of macro- and microvasculature, providing information to help delineate malignant from non-malignant processes. The use of CEUS may significantly increase the sensitivity and specificity over conventional endoscopic ultrasound. Currently available contrast agents are safe, with infrequent adverse effects. This review summarizes the theory and technique behind CEUS and the current and future clinical applications.

Solid tumors of the body and tail of the pancreas

Solid lesions of the body and tail of the pancreas challenge all the diagnostic and technical skills of the modern gastrointestinal surgeon. The information available from modern computed tomography (CT), magnetic resonance (MR), and endoscopic ultrasound (EUS) imaging provide diagnostic and anatomic data that give the surgeon precise information with which to plan an operation and to discuss with the patient during the preoperative visit. A preoperative evaluation includes a thorough history and a pancreas protocol CT scan, supplemented by MR imaging and EUS when needed, to differentiate between the various potential diagnoses. These same modalities can be essential in proper staging in the case of malignant lesions, thus aiding in management decisions. Most lesions ultimately require operative resection, barring metastatic disease, with the notable exception of autoimmune pancreatitis.

[Diagnostic and interventional endoscopy in gastroenterology : from high-resolution chips and procedures for endoscopic resection to NOTES]

In the past 10 years endoscopic diagnostics has benefited from technologies such as big chips, high-definition television (HDTV) and narrow band imaging (NBI). Video capsule endoscopy and double balloon enteroscopy have facilitated visualization of the entire small bowel. A number of studies on mucosal Barrett's and gastric cancers could prove that endoscopic mucosal resection (EMR) is oncologically equivalent to surgical resection when certain criteria are respected. However, EMR is less invasive and carries a substantially lower complication risk and mortality compared to surgery. Endoscopic submucosal dissection (ESD) facilitates en bloc resection with thorough histopathologic evaluation of the specimen, e.g. for mucosal lesions in the stomach and rectum. Endosonography (EUS) guided transgastric necrosectomy using a flexible gastroscope has set a milestone in the treatment of infected pancreatic necroses and has replaced open surgery in many centers. Natural orifice transluminal endoscopic surgery (NOTES) uses natural body openings as minimally invasive access to the abdomen and mediastinum. Interventional GI endoscopists and minimally invasive surgeons have profited from these innovations in micromechanics and microelectronics.