Utilization of ancillary studies in the cytologic diagnosis of biliary and pancreatic lesions: The Papanicolaou Society of Cytopathology Guidelines

Abstract

The Papanicolaou Society of Cytopathology has developed a set of guidelines for pancreatobiliary cytology including indications for endoscopic ultrasound guided fine needle aspiration, terminology and nomenclature of pancreatobiliary disease, ancillary testing and post-biopsy management. All documents are based on the expertise of the authors, a review of the literature, discussion of the draft document at several national and international meetings and synthesis of selected online comments of the draft document. This document presents the results of these discussions regarding the use of ancillary testing in the cytologic diagnosis of biliary and pancreatic lesions. Currently, fluorescence in-situ hybridization (FISH) appears to be the most clinically relevant ancillary technique for cytology of bile duct strictures. The addition of FISH analysis to routine cytologic evaluation appears to yield the highest sensitivity without loss in specificity. Loss of immunohistochemical staining for the protein product of the SMAD4 gene and positive staining for mesothelin support a diagnosis of ductal adenocarcinoma. Immunohistochemical markers for endocrine and exocrine differentiation are sufficient for a diagnosis of endocrine and acinar tumors. Nuclear staining for beta-catenin supports a diagnosis of solid-pseudopapillary neoplasm. Cyst fluid analysis for amylase and carcinoembryonic antigen aids in the pre-operative classification of pancreatic cysts. A number of gene mutations (KRAS, GNAS, von Hippel-Lindau, RNF43 and CTNNB1) may be of aid in the diagnosis of cystic neoplasms. Other ancillary techniques do not appear to improve diagnostic sensitivity sufficiently to justify their increased costs.

Impact of next-generation sequencing on the clinical diagnosis of pancreatic cysts

“…Molecular analysis of pancreatic cysts is an evolving tool for the evaluation of pancreatic cysts and has been shown to aid in the preoperative diagnosis. 23,[25][26][27][38][39][40][41][42] Our study investigated the impact of NGS on the presumptive clinical diagnosis of pancreatic cysts based on imaging features and clinical diagnosis based on CEA levels of the fluid. Our data show that NGS analysis of pancreatic cyst fluid changed the imaging diagnosis in 12% of patients, thus affecting patient management.…”

Fully automated PCR detection of KRAS mutations on pancreatic endoscopic ultrasound fine-needle aspirates

“…Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) plays a crucial role in the management of pancreatic neoplastic lesions 1. More than 85% of pancreatic adenocarcinoma (PDAC) are diagnosed by EUS-FNA in an advanced stage when surgical pathological examination is precluded 2.…”

Management of malignant distal biliary obstruction

“…[23][24][25] Given these findings, the use of FISH in the setting of negative or indeterminate routine cytology has been recommended in recent guidelines by The Papanicolaou Society of Cytopathology. 26 Endoscopic therapy…”