Revised international consensus guidelines for the management of patients with mucinous cysts

Cytologic Assessment of Cystic/Intraductal Lesions of the Pancreatobiliary Tract

CONTEXT.—

Because of new and improved imaging techniques, cystic/intraductal pancreatobiliary tract lesions are increasingly being discovered, and brushings or endoscopic ultrasound/computed tomography/magnetic resonance imaging-guided fine-needle aspiration biopsies from these lesions have become an integral part of pathologists' daily practice. Because patient management has become increasingly conservative, accurate preoperative diagnosis is critical. Cytologic distinction of low-risk (pseudocysts, serous cystadenoma, lymphoepithelial cysts, and squamoid cysts of the pancreatic duct) from high-risk pancreatic cysts (intraductal papillary mucinous neoplasm and mucinous cystic neoplasm) requires incorporation of clinical, radiologic, and cytologic findings, in conjunction with chemical and molecular analysis of cyst fluid. Cytopathologists must ensure appropriate specimen triage, along with cytologic interpretation, cyst classification, and even grading of some (mucinous) cysts. Epithelial atypia in mucinous cysts (intraductal papillary mucinous neoplasm and mucinous cystic neoplasm) has transitioned from a 3-tiered to a 2-tiered classification system, and intraductal oncocytic papillary neoplasms and intraductal tubulopapillary neoplasms have been separately reclassified because of their distinctive clinicopathologic characteristics. Because these lesions may be sampled on brushing or fine-needle aspiration biopsy, knowledge of their cytomorphology is critical.

OBJECTIVE.—

To use an integrated, multidisciplinary approach for the evaluation of cystic/intraductal pancreatobiliary tract lesions (incorporating clinical, radiologic, and cytologic findings with [chemical/molecular] cyst fluid analysis and ancillary stains) for definitive diagnosis and classification.

DATA SOURCES.—

Review of current literature on the cytopathology of cystic/intraductal pancreatobiliary tract lesions.

CONCLUSIONS.—

Our knowledge/understanding of recent updates in cystic/intraductal pancreatobiliary lesions can ensure that cytopathologists appropriately triage specimens, judiciously use and interpret ancillary studies, and incorporate the studies into reporting.

EUS-FNA diagnosis of pancreatic serous cystadenoma with the aid of cell blocks and α-inhibin immunochemistry: A case series

Serous cystadenoma (SCA) is an uncommon benign pancreatic neoplasm that is most often managed conservatively with follow-up rather than surgical excision. Therefore, to avoid the serious complications of pancreatic surgery, SCA should be diagnosed accurately at the preoperative level. Preoperative SCA diagnosis requires a multimodal diagnostic approach that includes imaging, cystic fluid biochemical analysis and/or endoscopic ultrasound fine-needle aspiration (EUS-FNA). In this brief report, we describe six EUS-FNA cases from five patients that were reported as "benign, consistent with serous cystadenoma". Samples were hypocellular, composed of loose clusters and single cuboidal, bland-looking cells among epithelial sheets representing gastrointestinal contamination. Cell blocks were prepared and all six FNA cases revealed cuboidal cells with a positive α-inhibin immunophenotype, consistent with a diagnosis of SCA. As EUS-FNAs of SCA commonly result in non-diagnostic interpretations, cell block preparations with subsequent immunochemistry can increase their diagnostic accuracy and guide patient management.

Imaging and Cytopathological Criteria Indicating Malignancy in Mucin-Producing Pancreatic Neoplasms: A Series of 68 Histopathologically Confirmed Cases

OBJECTIVES

This study aims to evaluate the performance of clinical, imaging, and cytopathological criteria in the identification of high-grade dysplasia/carcinoma (HGD/Ca) in pancreatic mucin-producing cystic neoplasms.

METHODS

Sixty-eight consecutive, histopathologically confirmed mucin-producing cystic neoplasms, evaluated by endoscopic ultrasound-guided fine-needle aspiration, were enrolled; specifically, 39 branch duct intraductal papillary mucinous neoplasms (BD-IPMNs), 21 main duct IPMNs, and 8 mucinous cystic neoplasms. The associations between HGD/Ca in histopathology and findings of endoscopic ultrasound and cytology, demographic, lifestyle, and clinical parameters were evaluated, separately in IPMNs and mucinous cystic neoplasms.

RESULTS

Age 65 years or more was associated with HGD/Ca in IPMNs. In BD-IPMNs, cyst diameter 3 cm or greater (sensitivity, 68.8%; specificity, 65.2%), a mural nodule (sensitivity, 56.3%; specificity, 78.3%), main pancreatic duct diameter 5 to 9 mm (sensitivity, 50.0%; specificity, 87.0%), and suspicious cytology (sensitivity, 81.3%; specificity, 100%) signaled the presence of HGD/Ca. Similarly, in main duct IPMNs, suspicious cytology predicted HGD/Ca with high sensitivity (88.9%) and excellent specificity (100%). Regarding cytopathological criteria, in BD-IPMNs, HGD/Ca was associated with a high nuclear/cytoplasmic ratio, background necrosis, presence of papillary structures, hypochromatic nuclei, hyperchromatic nuclei, and major nuclear membrane irregularities (thickening and/or indentations).

CONCLUSIONS

Clinical, imaging, and cytopathological criteria are useful in the identification of HGD/Ca in IPMNs.

Pancreatic fine-needle aspiration cytopathology: an analysis of the CAP NGC program for pancreatic FNA 2003-2011

INTRODUCTION

The College of American Pathologists monitors quality in cytologic analysis in its nongynecologic cytology sample program. We report the performance of participating laboratories in pancreatic fine-needle aspiration sample analysis.

MATERIALS AND METHODS

We evaluated 23,079 responses to 392 pancreatic fine-needle aspiration slide challenges that were collected between January 6, 2003 and December 31, 2011. The analysis examined concordance to the reference diagnosis as well as performance of conventional Papanicolaou smears, Romanowsky smears, CytoSpin and ThinPrep preparations. A nonlinear mixed model was fit with 3 factors: reference diagnosis, reader type, and preparation type.

RESULTS

Overall concordance rate was 93.2%, 94.8% for ductal adenocarcinoma, and 96.2% for interpretation of malignancy in cases of neuroendocrine tumors. There was no difference in performance between pathologists and cytotechnologists. In negative/benign preparations, there was a 76.3% concordance to the reference diagnosis. There was 89.2% sensitivity for diagnosis of malignancy when adenocarcinoma was present and 72.8% specificity for a benign non-neoplastic diagnosis with a tendency to overcall and demonstrate insecurity by providing a number of incorrect diagnoses for benign entities. Sensitivity of an exact diagnosis of neuroendocrine lesion when a neuroendocrine tumor is present was 79%. Concordance for diagnosis of mucinous cystic neoplasm without cytologic atypia was problematic at 46.4% with participants yielding an erroneous interpretation of adenocarcinoma one-third of the time.

CONCLUSIONS

Participants performed well in recognizing adenocarcinoma, but they overcalled negative samples. Findings can provide focus for education and suggest that efforts be directed at benign pancreatic samples, neuroendocrine cytomorphology, and mucinous neoplasms.

Intraductal papillary mucinous neoplasm: clinical surveillance and management decisions

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a relatively rare cystic neoplasm. Although most IPMNs appear to be benign and may be managed by surveillance, all IPMNs are considered premalignant lesions with malignant potential. As such, current efforts are focused on identifying those neoplasms that are at high risk for malignancy to optimize treatment strategy and outcome. IPMNs with invasive carcinoma have clinical outcomes that approach those of conventional pancreatic ductal adenocarcinoma. Management guidelines recommend surgical resection for IPMNs with high-risk imaging or cytologic features. The role of adjuvant therapy is unclear, and we review the evidence for chemoradiation here. Some studies suggest adjuvant chemoradiation may have the greatest impact in malignant IPMNs with adverse histologic features, that is, lymph node metastasis at the time of diagnosis or positive surgical margins. As more IPMNs are recognized and treated, more evidence will accumulate to guide clinicians regarding appropriate use of radiotherapy in the management of IPMN.

Moving beyond morphology: new insights into the characterization and management of cystic pancreatic lesions

The frequency of detection of cystic pancreatic lesions with cross-sectional imaging, particularly with multidetector computed tomography, magnetic resonance (MR) imaging, and MR cholangiopancreatography, is increasing, and many of these cystic pancreatic lesions are being detected incidentally in asymptomatic patients. Because there is considerable overlap in the cross-sectional imaging findings of cystic pancreatic lesions, and because many of these lesions being detected are smaller than 3 cm in diameter and lack any specific cross-sectional imaging features, it has become difficult to make informed decisions about patient management when the precise diagnosis remains uncertain. This article presents the limitations of cross-sectional imaging in patients with cystic pancreatic lesions, details advances in knowledge of the genomic and epigenomic changes that lead to progression of carcinogenesis, outlines the current understanding of the natural history of mucinous cystic lesions, and includes the current use and future potential of novel tumor markers and molecular analysis to characterize cystic pancreatic lesions more precisely. The need to move beyond cross-sectional imaging morphology and toward the use of new techniques to diagnose these lesions accurately is emphasized. An algorithm that uses these techniques is proposed and will hopefully lead to improved patient management.

Endoscopic techniques for diagnosis and therapy of pancreatic intraductal papillary mucinous neoplasm

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a cystic neoplasm with potential malignancy. In the past, screening of IPMN depended on traditional imaging examinations, such as transabdominal ultrasonography and computed tomography (CT). With the development of endoscopic techniques, endoscopic ultrasound (EUS), endoscopic retrograde cholangiopancreatography (ERCP) and other endoscopic techniques are becoming significant diagnostic methods for IPMN. Meanwhile, endoscopic interventional therapy with the advantage of minimal invasiveness has been used to treat some patients who cannot tolerate or refuse surgery. This paper elucidates the advances in diagnosis and therapy of pancreatic IPMNs using endoscopic techniques.

Post-brushing and fine-needle aspiration biopsy follow-up and treatment options for patients with pancreatobiliary lesions: The Papanicolaou Society of Cytopathology Guidelines

The Papanicolaou Society of Cytopathology (PSC) has developed a set of guidelines for pancreatobiliary cytology including indications for endoscopic ultrasound (EUS) guided fine-needle aspiration (FNA) biopsy, techniques of EUS-FNA, terminology and nomenclature for pancreatobiliary cytology, ancillary testing and post-procedure management. All documents are based on the expertise of the authors, a review of the literature and discussions of the draft document at several national and international meetings over an 18 month period and synthesis of online comments of the draft document on the PSC web site (www.papsociety.org). This document selectively presents the results of these discussions and focuses on the follow-up and treatment options for patients after procedures performed for obtaining cytology samples for the evaluation of biliary strictures and solid and cystic masses in the pancreas. These recommendations follow the six-tiered terminology and nomenclature scheme proposed by committee III.

To cease or 'de-cyst'? The evaluation and management of pancreatic cystic lesions

Due to the widespread use of cross-sectional imaging and advances in imaging technology, pancreatic cystic lesions are increasingly being detected. The diagnosis and management of such cysts remains challenging and continues to evolve. Different pancreatic cyst types have varying malignant potential. Thus, accurate cyst characterization is essential to appropriate management; the most clinically important distinction is differentiating mucinous lesions, which have malignant potential and may benefit from surgical resection, from non-mucinous cystic lesions. Endoscopic ultrasound with fine needle aspiration with cytologic, chemical,, and tumor marker analysis appears to be the best currently available method for accurately characterizing a cyst's malignant potential, and therefore impacts the most important management decision for a pancreatic cyst-continued surveillance or surgical resection.