Revisiting the performance of cyst fluid carcinoembryonic antigen as a diagnostic marker for pancreatic mucinous cysts: a comprehensive 20-year institutional review.

OBJECTIVE: Elevated pancreatic cyst fluid carcinoembryonic antigen (CEA) has been routinely used to classify mucinous cysts. This study incorporates original data that established the CEA ≥192 ng/mL threshold with over 20 years of additional data and reassesses the diagnostic performance of CEA for differentiating mucinous from non-mucinous cysts. DESIGN: 1169 pancreatic cysts (1999-2021) with CEA results were identified. 394 cases had histological confirmation as the diagnostic standard. Additionally, 237 cysts without histological confirmation demonstrated KRAS, GNAS, or RNF43 mutations by molecular testing and were combined with the histologically confirmed cysts for separate analysis on a total cohort of 631 cysts. RESULTS: Median CEA was significantly higher in mucinous cysts (323.9 ng/mL, n=314) versus non-mucinous cysts (204.6 ng/mL, n=80) (p<0.001). Receiver operating characteristic curve analysis demonstrated an optimal CEA cut-off of 20 ng/mL (area under the curve: 80%), though the specificity was lower than desired (sensitivity 89%, specificity 64%). At the previously established threshold of 192 ng/mL, sensitivity and specificity were 56% and 78%, respectively. To achieve a specificity of 85% as originally reported, a CEA threshold of 250 ng/mL was needed; the 13 false positive cases at this threshold included 4 benign simple cysts, 2 squamoid cysts, 1 serous cystadenoma, 1 lymphoepithelial cyst and 5 more uncommon entities. All results remained similar within the total cohort after including additional cases with KRAS/GNAS/RNF43 mutations only. CONCLUSION: Cyst fluid CEA continues to be a useful test in the diagnosis of mucinous pancreatic cysts but does not appear as specific as previously reported. Raising the CEA threshold to 250 ng/mL to maintain specificity for differentiating mucinous from non-mucinous cysts may be considered.

Next-generation sequencing in the evaluation of biliary strictures in patients with primary sclerosing cholangitis.

BACKGROUND: Primary sclerosing cholangitis (PSC) is a well-described risk factor for the development of cholangiocarcinoma (CCA). Early detection of CCA in these patients is of great importance because it expands options for therapeutic interventions, including liver transplantation. Current diagnostic tests for the evaluation of biliary strictures are limited to biliary brushing (BB) cytology and fluorescence in situ hybridization (FISH). Next-generation sequencing (NGS) has become an important diagnostic tool in oncology and may be a useful tool for diagnosing CCA on BBs. It is not clear how NGS performs when it is added to BB cytology and FISH in patients with PSC. METHODS: This study reports the authors' experience with NGS performed as a prospective cotest with cytology and FISH on BBs obtained from 60 patients with PSC followed at Massachusetts General Hospital. A duct with malignancy was defined as a high-risk (HR) stricture with either high-grade dysplasia or CCA. RESULTS: NGS was better than FISH and cytology in detecting HR strictures, which showed multiple genetic mutations in all cases. NGS provided specific mutational information, and NGS results were reproducible in longitudinal samples. CONCLUSIONS: Adding NGS to BB cytology and FISH in the evaluation of biliary strictures for patients with PSC may provide additional information that could help to inform clinical management.

Clinical evaluation, imaging studies, indications for cytologic study and preprocedural requirements for duct brushing studies and pancreatic fine-needle aspiration: The Papanicolaou Society of Cytopathology Guidelines.

The Papanicolaou Society of Cytopathology has developed a set of guidelines for pancreaticobiliary cytology including indications for endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) biopsy, techniques for EUS-FNA, terminology and nomenclature to be used for pancreaticobiliary disease, ancillary testing and postbiopsy management. All documents are based on expertise of the authors, literature review, discussions of the draft document at national and international meetings and synthesis of online comments of the draft document. This document selectively presents the results of these discussions. This document summarizes recommendations for the clinical and imaging work-up of pancreatic and biliary tract lesions along with indications for cytologic study of these lesions. Prebrushing and FNA requirements are also discussed.

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.

Postbrushing 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 postprocedure management. All documents are based on the expertise of the authors, a review of the literature, 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.

International consensus guidelines 2012 for the management of IPMN and MCN of the pancreas.

The international consensus guidelines for management of intraductal papillary mucinous neoplasm and mucinous cystic neoplasm of the pancreas established in 2006 have increased awareness and improved the management of these entities. During the subsequent 5 years, a considerable amount of information has been added to the literature. Based on a consensus symposium held during the 14th meeting of the International Association of Pancreatology in Fukuoka, Japan, in 2010, the working group has generated new guidelines. Since the levels of evidence for all items addressed in these guidelines are low, being 4 or 5, we still have to designate them "consensus", rather than "evidence-based", guidelines. To simplify the entire guidelines, we have adopted a statement format that differs from the 2006 guidelines, although the headings are similar to the previous guidelines, i.e., classification, investigation, indications for and methods of resection and other treatments, histological aspects, and methods of follow-up. The present guidelines include recent information and recommendations based on our current understanding, and highlight issues that remain controversial and areas where further research is required.

Cytology adds value to imaging studies for risk assessment of malignancy in pancreatic mucinous cysts.

OBJECTIVE: Evaluate the value of cytology relative to imaging features in risk assessment for malignancy as defined in the Sendai Guidelines. BACKGROUND: The Sendai Guidelines list symptoms, cyst size >30 mm, dilated main pancreatic duct (MPD) >6 mm, mural nodule (MN) and "positive" cytology as high risk stigmata for malignancy warranting surgical triage. METHODS: We reviewed clinical, radiological and cytological data of 112 patients with histologically confirmed mucinous cysts of the pancreas evaluated in a single tertiary medical center. Cytology slides were blindly re-reviewed and epithelial cells grouped as either benign or high-grade atypia (HGA) [≥high-grade dysplasia]. Histologically, neoplasms were grouped as benign (low-grade and moderate dysplasia) and malignant (in situ and invasive carcinoma). Performance characteristics of cytology relative to other risk factors were evaluated. RESULTS: Dilated MPD, MN, and HGA were independent predictors of malignancy (p < 0.0001), but not symptoms (p = 0.29) or cyst size >30 mm (p = 0.51). HGA was the most sensitive predictor of malignancy in all cysts (72%) and in small (≤30 mm) branch-duct intraductal papillary mucinous neoplasm (BD IPMN; 67%), whereas also being specific (85 and 88%, respectively). MN and dilated MPD were highly specific (>90%), but insensitive (39%-44%). Cytology detected 30% more cancers in small cysts than dilated MPD or MN and half of the cancers without either of these high-risk imaging features. CONCLUSIONS: Cytology adds value to the radiological assessment of predicting malignancy in mucinous cysts, particularly in small BD IPMN.

High-grade atypical epithelial cells in pancreatic mucinous cysts are a more accurate predictor of malignancy than "positive" cytology.

BACKGROUND: The Sendai guidelines for risk assessment of malignancy in patients with mucinous cysts lists "positive" cytology as a high-risk feature. In the current study, the authors hypothesized that a cytological threshold of high-grade atypical epithelial cells (AEC) is a more accurate predictor of malignancy. METHODS: The clinical, radiological, and cytological data of 112 patients with histologically confirmed mucinous cysts of the pancreas were reviewed. Cytology slides were blindly reviewed and cells were classified as benign, AEC, or malignant. On histology, neoplasms were grouped as benign (low-grade and moderate dysplasia) and malignant (high-grade dysplasia/carcinoma in situ and invasive carcinoma). RESULTS: There were 92 patients with an intraductal papillary mucinous neoplasm (IPMN) and 20 with a mucinous cystic neoplasm; 39 were malignant and 73 were benign (42 with low-grade dysplasia and 31 with moderate dysplasia). Only 28% (11 of 39) of the malignant cysts were cytologically malignant with a sensitivity of 29%, a specificity of 100%, and an accuracy of 75%. AEC detected 17 additional cancers (44% of all malignant cysts; 16% more than detected on the basis of "positive" cytology). By using AEC as a surgical triage threshold, the sensitivity was 72%, the specificity was 85%, and the accuracy was 80%, with similar values for small (≤ 3 cm) branch duct IPMN. Nine of 73 (12%) benign cysts were identified with AEC, 4 of which had moderate dysplasia. AEC had a positive predictive value of 87% for the detection of a mucinous cyst with moderate dysplasia or worse. CONCLUSIONS: AEC are a more accurate predictor of malignancy than "positive" cytology in aspirates of pancreatic mucinous cysts, including small branch duct IPMN. AEC warrant a "suspicious" interpretation for appropriate surgical triage.

Pancreatic cysts: preoperative diagnosis and clinical management.

Preoperative diagnosis of pancreatic cysts benefits from integrating the clinical, radiological, and cytological features. As patient management algorithms evolve to increasingly nonsurgical options, accuracy in distinguishing mucinous from nonmucinous and benign from malignant mucinous cysts is important. This review focuses on pseudocysts, serous cystadenomas, intraductal papillary mucinous neoplasms (IPMNs), and mucinous cystic neoplasms. Patients with pseudocysts almost always present with pancreatitis and are usually medically managed. Radiological studies reveal a unilocular cyst mostly in the pancreatic tail. Cyst fluid is thin, with high amylase but low carcinoembryonic antigen (CEA) levels. DNA mutations are absent. Serous cystadenomas are benign and do not require resection. Patients are usually asymptomatic and have microcystic or macrocystic masses anywhere in the pancreas. Cytology is frequently nondiagnostic. CEA and amylase levels are low. DNA analysis may reveal loss of heterozygosity (LOH) at 3p if associated with Von Hippel-Lindau disease. Neoplastic mucinous cysts are highly variable in their presentation. Most are resected. Mucinous cystic neoplasms typically arise in the body or tail of the pancreas of middle-aged women and demonstrate a septated cyst without dilatation of the main pancreatic duct. Branch duct IPMNs are more common in the pancreatic head of elderly men. Main duct dilatation correlates with main duct or combined type IPMN. Both types of mucinous cysts produce variable amounts of mucin. Cytologically nonmalignant but atypical epithelial cells, even when scant, are an indication of a high risk for malignancy. High CEA level supports a mucinous cyst, as do KRAS mutation and good quality DNA levels. KRAS mutation and multiple LOH support malignancy.

Diagnosis of pancreatic neoplasia with EUS and FNA: a report of accuracy.

BACKGROUND: EUS-guided FNA has the potential to provide diagnostic cytologic material from pancreatic lesions that are suspicious for malignancy. OBJECTIVE: To determine the operating characteristics of EUS-FNA in the diagnosis of pancreatic adenocarcinoma and pancreatic neuroendocrine neoplasms (PENs). DESIGN: Retrospective analysis of a prospectively maintained database. SETTING: Academic tertiary-care center. PATIENTS: This study involved 559 patients undergoing evaluation of pancreatic masses or diffuse pancreatic parenchymal abnormalities. MAIN OUTCOME MEASUREMENTS: Performance characteristics of EUS-FNA of pancreatic adenocarcinoma and PEN. RESULTS: From January 1997 to December 2005, 737 patients undergoing initial EUS-FNA evaluation for a pancreatic mass were identified. In the final analysis, 559 patients with 560 FNA-sampled lesions were included. Overall, 442 lesions were pancreatic adenocarcinoma, and 40 were PEN. The sensitivity of EUS-FNA in the diagnosis of pancreatic adenocarcinomas and PENs was 77% (95% CI, 72.8%-80.8%) and 68% (95% CI, 50.8%-80.9%), respectively, using strict cytologic criteria. Reclassification of atypical and suspicious cytologies as diagnostic of malignancy resulted in a sensitivity of 93%, (95% CI, 90.9%-99.7%) in adenocarcinoma and 80% (95% CI, 63.9%-90.4%) in PEN. Tumor size, tumor location, and number of needle passes did not significantly influence diagnosis, but immediate cytologic evaluation was influential. LIMITATIONS: Retrospective analysis at a single center. CONCLUSIONS: In a large, well-controlled study, EUS-FNA was found to be an accurate test (80%) for the detection of pancreatic adenocarcinoma by using aspiration cytology. The accuracy of the examination is significantly improved (94%) when atypical and suspicious samples are considered positive. Finally, only 2 to 3 FNA passes may be needed to achieve a good diagnostic yield.