Accuracy and agreement of a large panel of endosonographers for endomicroscopy-guided virtual biopsy of pancreatic cystic lesions.

BACKGROUND: Although emerging data evidences that EUS-guided needle-based confocal laser endomicroscopy (nCLE) accurately diagnoses pancreatic cystic lesions (PCLs), there are a lack of interobserver agreement (IOA) studies utilizing reference histopathological diagnosis and for specific PCL subtypes. Hence, we sought to assess the IOA, intra-observer reliability (IOR), and diagnostic performance of EUS-nCLE using a large cohort of patients with histopathological diagnosis amongst a broad panel of international observers. METHODS: EUS-nCLE videos (n = 76) of subjects with PCLs [intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), serous cystadenoma (SCA), pseudocyst, and cystic-neuroendocrine tumors/solid pseudopapillary neoplasm (cystic-NET/SPN)], simulating clinical prevalence rates were obtained from 3 prospective studies. An international panel of 13 endosonographers with nCLE experience, blinded to all PCL data, evaluated the video library twice with a two-week washout for PCL differentiation (mucinous vs. non-mucinous) and subtype diagnosis. RESULTS: The IOA (κ = 0.82, 95% CI 0.77-0.87) and IOR (κ = 0.82, 95% CI 0.78-0.85) were "almost perfect" to differentiate mucinous vs. non-mucinous PCLs. For PCL subtype, IOA was highest for SCA (almost perfect; κ = 0.85), followed by IPMN (substantial, κ = 0.72), and cystic-NET/SPN (substantial, κ = 0.73). The IOA was moderate for MCN (κ = 0.47), and pseudocyst (κ = 0.57). Compared to histopathology, observers differentiated mucinous vs. non-mucinous PCLs with high accuracy (94.8%, 95% CI 93.3-96.1). For detecting specific PCLs subtypes, EUS-nCLE was highly accurate in diagnosing non-mucinous cysts (SCA: 98%; cystic-NET/SPN: 96%; pseudocyst: 96%) and slightly less accurate for mucinous lesions (IPMN: 86%; MCN: 84%). CONCLUSION: Diagnosis of PCLs by EUS-nCLE guided virtual biopsy is very accurate and reliable for the most prevalent pancreatic cysts in clinical practice.

Requirement of a single high-risk feature as an indication for EUS for the diagnosis of asymptomatic pancreatic cysts.

BACKGROUND AND AIMS: Endoscopic ultrasound (EUS) is widely used to evaluate pancreatic cysts. Recent American Gastroenterological Association (AGA) guideline limits EUS for evaluation of cysts with at-least two high-risk features (size ≥ 3 cm, dilated main pancreatic duct or presence of a solid component). We have investigated the impact of this guideline on sensitivity of EUS for pancreatic cancer and the reduction of EUS procedures for pancreas cysts. METHODS: EUS procedures performed between 2004 and 2015 and related patient records were retrospectively reviewed to determine the presence or absence of high-risk features, and for the results of fine needle aspiration cytology. RESULTS: Two hundred ten patients (108 males) underwent EUS for diagnostic evaluation of pancreatic cysts. Four patients (1.9%), all with at-least one high-risk feature, were diagnosed with cytologically-proven pancreatic cancer. Only 2 patients with cancer had at-least two high-risk features that would have warranted EUS examination based on the new AGA guideline. The requirement for at-least two high-risk features would have decreased the number of EUS procedures by 91%, but reduced the sensitivity for pancreatic malignancy to 50%. If only one high-risk feature was required, EUS procedures would have been decreased by 67%, with a sensitivity of 100%. CONCLUSION: Limiting EUS to patients with pancreatic cysts with 2 or more high-risk features may substantially reduce the sensitivity for pancreatic malignancy. Performing EUS in patients with at least one high-risk feature may substantially decrease the need of invasive procedures without reducing sensitivity for detecting malignancy.

EUS and EUS-FNA diagnosis of suspected pancreatic cystic neoplasms: Is the sum of the parts greater than the CEA?

BACKGROUND: Carcinoembryonic antigen (CEA) is suggested as the single most useful EUS/EUS-FNA derived test for the diagnosis of mucinous pancreatic cysts. STUDY AIMS: To investigate the yield and diagnostic performance of EUS/EUS-FNA on an intention to diagnose basis and to determine the utility of the recommended CEA and amylase cut-off values. PATIENTS AND METHODS: A retrospective study of a prospectively maintained database of 433 procedures performed in a 10 year period. Diagnostic performance of EUS-FNA was determined in 133 procedures with a definite diagnosis. RESULTS: CEA value was determined in significantly fewer procedures (58.6%) than EUS diagnosis was stated (83.4%; p < 0.0001), cyst fluid appearance recorded (89.4%) or adequate sample for cytology obtained (76.7%; p < 0.005). Median CEA was significantly higher in mucinous cysts than non-mucinous (175 ng/ml vs 3 ng/ml, p < 0.0001) and in malignant cysts compared to benign (8945 ng/ml vs 93 ng/ml, p < 0.001). On an intention-to-diagnose analysis, a CEA cut-off of 110 ng/ml was significantly less accurate (42.8%) than EUS diagnosis (67.7%), cytology (58.6%) or aspirate appearance (66.9%; p < 0.05 for all comparisons). However, the combination of EUS diagnosis, cytology and CEA provided higher sensitivity (91%), specificity (75%) and accuracy (85.7%) than each component test alone (p < 0.05 for all comparisons). Median amylase was significantly higher in benign compared to high-risk mucinous cysts ((11,429IU/L vs. 113IU/L; p < 0.05. CONCLUSION: The combination of EUS, cytology and CEA performed well. Malignant cysts had a higher CEA value than benign cysts. On an intention to diagnose basis a CEA cut-off of 110 ng/ml performed poorly.

Imaging of pancreatic serous cystadenoma and common imitators.

Pancreatic cystic neoplasms are lesions comprised of cystic components that show different biological behaviors, epidemiology, clinical manifestations, imaging features, and malignant potential and management. Benign cystic neoplasms include serous cystic neoplasms (SCAs). Other pancreatic cystic lesions have malignant potential, such as intraductal papillary mucinous neoplasms and mucinous cystic neoplasms. SCAs can be divided into microcystic (classic appearance), honeycomb, oligocystic/macrocystic, and solid patterns based on imaging appearance. They are usually solitary but may be multiple in von Hippel-Lindau disease, which may depict disseminated involvement. The variable appearances of SCAs can mimic other types of pancreatic cystic lesions, and cross-sectional imaging plays an important role in their differential diagnosis. Endoscopic ultrasonography has helped in improving diagnostic accuracy of pancreatic cystic lesions by guiding tissue sampling (biopsy) or cyst fluid analysis. Immunohistochemistry and newer techniques such as radiomics have shown improved performance for preoperatively discriminating SCAs and their mimickers.

Calcified Cystic Lesion of the Pancreas.

Pancreatic cystic lesion is a relatively uncommon condition with an estimated prevalence of 2 % in the general population. In the past two decades, there has been a dramatic increase in the prevalence of pancreatic cystic lesions because of the widespread use of high-resolution imaging, as well as the aging of the population. Pancreatic cystic lesions cover a wide spectrum of pathology and can range from obviously benign to borderline malignant potential lesions to overt malignancy. Though the presence of mural nodules, septa-like structures, or calcification on imaging examination contributes to the differential diagnosis, preoperatively determining the biological nature of these cystic lesions is sometimes challenging. In this paper, we report a rare case of pancreatic cystic lesion with an egg-shell like calcification. Complete resection was performed and histological examination confirmed the diagnosis of calcified pancreatic pseudocyst.

Lymphoepithelial Cyst of the Pancreas: A Case Report

We present a case of lymphoepithelial cyst of the pancreas. The cyst showed moderate echogenicity, mimicking a solid lesion on ultrasonography (US), and had a cystic appearance on computed tomography (CT). This ambivalent finding may be a distinctive feature of lymphoepithelial cysts of the pancreas.

Lymphoepithelial Cyst of the Pancreas: A Case Report

Lymphoepithelial cyst of the pancreas is a very rare lesion of unknown etiology. It is difficult, on the basis of radiologic images, to differentiate between lymphoepithelial cyst and pancreatic pseudocyst or other cystic neoplasms, particularly if these are mucinous. We describe the sonographic and CT findings in a case of surgically proven lymphoepithelial cyst of the pancreas.

Mixed Microcystic and Macrocystic Serous Cystadenoma of the Pancreas: A Case Report

Serous cystadenomas of the pancreas are generally considered to be microcystic adenomas. Typical serous cystadenomas of the pancreas are encapsulated tumors composed of tiny cysts less than 2 cm in size showing sponge-like appearance with a central stellate scar or calcification on the cross-section. It has been recently reported, however, that serous cystadenomas may have macrocystic variants (major cysts more than 2 cm in size) that are radiologically indistinguishable from mucinous cystadenomas of the pancreas. We report the CT and MR imaging findings in a patient with mixed microcystic and macrocystic serous cystadenoma of the pancreas, indicating the histopathologic correlation. The mass was composed of two different types of cyst: multiple, small (2 cm) with peripheral calcification.

Lymphoepithelial Cyst of the Pancreas: A Report of 2 Cases

Two cases of lymphoepithelial cyst, a very rare cystic lesion of the pancreas, are reported. The patients complained of vague upper abdominal discomfort. One lesion was derived from the head of the pancreas, the other from its neck. Ultrasonographic finding of the former was a cystic lesion with inhomogeneous internal echogenecity, and in both cases, CT showed multiloculated cystic lesions with internal septa. Cysts filled with sebaceous material were excised on operation, and lymphoepithelial cyst was histopathologically confirmed.

Von Hippel-Lindau disease: A Case Report

Von Hippel-Lindau disease is an autosomal dominant disorder characterized by the presence of multiple benign and malignant tumors including hemangioblastomas of the retina and central nervous system, pancreatic cysts and tumors, renal cell carcinomas, pheochromocytomas and epididymal cystadenomas. We report the radiologic findings of a case of von Hippel-Lindau disease, describing the family history.

Radiologic Findings of the Serous Cystadenomas of the Pancreas with Macro cystic or Unilocular Variants: Comparison with the Pathologic Findings

PURPOSE: To evaluate the radiologic findings of the serous cystadenomas of the pancreas with macrocystic or unilocular variants and to compare them with the pathologic findings. MATERIALS AND METHODS: In eight patients(7 females and 1 male ranging in age from 26 to 49 [mean, 37] years) with surgically proven serous cystadenomas, the findings of abdominal CT(n=8), abdominal sonography(US, n=8), endoscopic retrograde pancreatography(ERCP, n=6), endoscopic sonography(EUS, n=3), and MRI(n=1) were evaluated. The location and size of tumors, lobulation, internal septa, solid component, calcification, communication with the pancreatic duct, dilatation of the proximal pancreatic duct, and contrast enhancement on CT were assessed and compared with the pathologic findings. RESULTS: Tumors were located in the head(n=3), body(n=3) and tail(n=2), and their mean size was 4 (range, 1 -8) cm. Abdominal CT scanning revealed well-defined cystic masses composed of macrocyst(s) with calcifica-tion(n=3) and dilatation of the proximal duct (n=2). Three cases showed contrast enhancement of the cystic walls, the pathologic examination of which revealed fibrotic tissues. Four tumeurs were unilocular without septation or lobulation; these features, together with calcification, were depicted more clearly by US and EUS. ERCP revealed no communication between the cysts and pancreatic ducts. Imaging studies showed that macrocystic adenomas were superimposed on mucinous cystadenomas, and unilocular adenomas were indis-tinguishable from pseudocysts. CONCLUSION: Serous cystadenomas of the pancreas with macrocystic or unilocular variants are common in middle-aged women. Features present due to the existence of fibrotic tissues, and which may be reveled by contrast-enhanced CT, include internal septa, calcification, duct dilation, and prominent enhancement of the cystic wall. Serous cystadenoma should be included in the differential diagnosis of macrocystic or unilocular cystic lesions of the pancreas.