Pancreatic and bile duct brushing cytology in 1000 cases: review of findings and comparison of preparation methods

Comprehensive Approach to Cytomorphology in Liquid-Based Bile Duct Brush Cytology: Integrating Cell Blocks and Histology

Bile duct brush cytology is a widely used and essential method for evaluating biliary tract lesions, although it remains challenging for pathologists. Liquid-based preparations provide a better vision of morphology and enable the preparation of cell blocks, thereby enhancing reliability. However, the establishment of reproducible interpretation criteria and utilization of cell blocks remain limited. This study aimed to investigate the morphological features of liquid-based cytology using objective and reproducible criteria, incorporating histological findings to identify diagnostic features. In total, 151 cases were selected and 42 morphologic criteria were evaluated within representative clusters. Notably, 14 features, including conventional cytologic features, significantly differed between the benign and malignant groups. Malignant cell clusters were more likely to be irregularly shaped and have larger nuclear sizes, increased nuclear pleomorphism, a non-euchromatic chromatin pattern, and a higher nucleus-to-cytoplasm (N/C) ratio. Multinucleation and nuclear molding were observed exclusively in malignant cases. The presence of inflammatory cells did not differ significantly between benign and malignant cases. An increased N/C ratio was observed in the cell blocks and the architectural information aided in diagnosis. The application of cell blocks may be beneficial, emphasizing the significance of nuclear pleomorphism. We also categorized features by analyzing the sensitivity, specificity, and importance of various features. In summary, our study reaffirms the importance of conventional cytomorphologic features in liquid-based preparations of bile duct cytology and suggests a diagnostic approach with more objective morphologic criteria, highlighting the utility of cell blocks.

The World Health Organization Reporting System for Pancreaticobiliary Cytopathology: Review and Comparison to the Papanicolaou Society of Cytopathology System

CONTEXT.—

The World Health Organization (WHO) Reporting System for Pancreaticobiliary Cytopathology (WHO System) is the product of a joint venture between the World Health Organization, the International Academy of Cytology, and the International Agency for Research on Cancer. The WHO System revises the Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology (PSC System) and replaces the 6-tiered system with a 7-tiered system.

OBJECTIVE.—

To explain the WHO System and the differences with the PSC System.

DATA SOURCES.—

The WHO System and the PSC System of Reporting Pancreaticobiliary Cytopathology.

CONCLUSIONS.—

The diagnostic categories of the WHO System are "Insufficient/Inadequate/Nondiagnostic"; "Benign (Negative for Malignancy)"; "Atypical"; "Pancreaticobiliary Neoplasm, Low Risk/Low Grade (PaN-Low)"; "Pancreatic Neoplasm, High Risk/High Grade (PaN-High)"; "Suspicious for Malignancy"; and "Malignant." In the WHO System, the "benign" category includes both nonneoplastic and neoplastic lesions, so the "Neoplastic: Benign" category of the PSC system has been eliminated. Low-grade malignancies, pancreatic neuroendocrine tumors (PanNETs), and solid-pseudopapillary neoplasm (SPN) classified as "Neoplastic: Other" in the PSC System are classified as "Malignant" in the WHO System, leaving in the "Neoplasm" category intraductal lesions, which are divided into 2 new diagnostic categories: "Pancreaticobiliary Neoplasm (PaN)-Low Risk/Grade" and "PaN-High Risk/Grade." As with the PSC System, the WHO System advocates close correlation with imaging and encourages incorporation of ancillary testing into the final diagnosis, such as biochemical (carcinoembryonic antigen [CEA] and amylase) and molecular testing. The WHO System includes risk of malignancy per category, and reporting and diagnostic management options that recognize the variations in resources of low- and middle-income countries.

Advances in diagnostic liquid-based cytology

Liquid-based cytology (LBC) has changed the landscape of gynaecological cytology. A growing demand exists for LBC in diagnostic cytology, particularly for ancillary testing, such as immunocytochemistry and molecular testing. Ancillary testing solely based on conventional preparation (CP) methods remains challenging. Recently, the increased demand for specialist testing and minimally invasive techniques, such as endoscopic ultrasonography fine-needle aspiration, to obtain cellular samples has led to an increasing demand for ancillary testing on cytology LBC supernatant, slides and cell block (CB). This facilitates the diagnosis and prognosis in cytology samples enabling personalized treatment. An understanding of the history and future prospects of LBC is crucial for its application in routine diagnostics by cytopathologists and cytotechnologists. In this review, we initiated an internet search using the keyword 'liquid-based cytology', and we conducted a literature review to discuss the usefulness of combined diagnosis of LBC and CP, immunocytochemistry and molecular testing and assessed the quality of nucleic acids in diagnostic LBC. High-quality and cell-rich diagnostic LBC surpassed the CP method alone in terms of reliability and versatility of ancillary testing in cytological diagnosis. Conclusively, diagnostic LBC lends itself to various new technologies and is expected to continue evolving with innovations in the future.

Cholangiocarcinoma of the Middle Bile Duct: A Narrative Review

Resectable cholangiocarcinoma (CCA) arising from the middle of the extrahepatic biliary tree has historically been classified as perihilar or distal CCA, depending on the operation contemplated or performed, namely the associated hepatectomy or pancreaticoduodenectomy, respectively. Segmental bile duct resection is a less invasive alternative for select patients harboring true middle extrahepatic CCA (MCC). A small, yet growing body of literature has emerged detailing institutional experiences with bile duct resection versus pancreaticoduodenectomy or concomitant hepatectomy for MCC. Herein, we provide a brief overview of the epidemiology, preoperative evaluation, and emerging systemic therapies for MCC, and narratively review the existing work comparing segmental resection with pancreaticoduodenectomy or less commonly, hepatectomy, for MCC, with emphasis on the surgical management and oncologic implications of the approach used.

Verifying a novel bile cytology scoring system

BACKGROUND

The scoring system for bile cytology (SSBC) aims to improve bile cytology diagnostic accuracy. Here, the practicality of SSBC was verified by multiple cytotechnologists.

METHODS

Bile cytological specimens were evaluated by 24 cytotechnologists using SSBC. The samples were assessed before using the SSBC (first-time assessment) according to three categories: benign, indeterminate, and malignant. A first scoring evaluation (FSE) was then performed using SSBC; each item in the scoring system was classified as present or absent. After distributing an instruction sheet with diagnostic criteria, a second scoring evaluation (SSE) was performed using SSBC. Each method was evaluated using diagnostic accuracy and interobserver and intraobserver agreement.

RESULTS

Several samples were assessed as indeterminate in the first-time assessment. Although the specificity of the SSE improved, the sensitivity and accuracy decreased compared with those of the FSE. The overall interobserver agreement was fair for all parameters, including abnormal chromatin, irregular internuclear distances, irregularly overlapped nuclei, irregular cluster margins, and final evaluation in the FSE and SSE. The final evaluation by histological type exhibited slight agreement for well-differentiated tubular adenocarcinoma and almost perfect agreement for poorly differentiated tubular adenocarcinoma in the FSE and SSE. For moderately differentiated tubular adenocarcinoma, agreement was moderate in the FSE and fair in the SSE. For cholangitis, a slight agreement was observed in the FSE, which improved to fair in the SSE.

CONCLUSIONS

Although the SSBC is expected to improve specificity, there exists ambiguity regarding SSBC criteria and interindividual assessment differences. Therefore, the objective assessment method should be revised.

Challenges and Pitfalls in Pancreatobiliary Cytopathology

INTRODUCTION

The advances of minimally invasive endoscopy-guided procedures that usually yield limited diagnostic material changed pancreaticobiliary cytopathology into one of the most challenging areas of cytopathology given the abundance of differential diagnoses to be considered when dealing with limited specimens.

CASE PRESENTATION

We describe a few challenging examples of potential pitfalls in pancreatobiliary cytopathology evaluation collected from a busy academic hospital (tertiary) center. Case 1 illustrates the challenges in handling paucicellular specimens from pancreatic solid lesions in which differential diagnoses may include acinar cell carcinoma, neuroendocrine tumors, adenocarcinoma, or even benign pancreatic tissue, among others. Case 2 illustrates the pitfalls in evaluating limited specimens from patients with chronic pancreatitis, specially when distinguishing exuberant reactive atypia from dysplastic changes is mandatory. Case 3 illustrates pitfalls in distinguishing malignancy from reactive changes in biliary brushing specimens from patients with primary sclerosing cholangitis. Finally, cases 4 and 5 highlight the importance of including the possibility of pancreatic metastasis in the differential diagnoses of some pancreatic lesions.

CONCLUSION

Over time, there has been an increasing demand for pathologists to render diagnoses on limited specimens obtained through minimally invasive procedures which can be frequently challenging even for the most experienced professionals. In many difficult cases, salvaging additional material for a cell block can turn out to be extremely helpful given the possibility of utilizing additional ancillary tests for diagnostic confirmation.

Diagnostic implication of extracellular mucin in pancreatic/biliary brushing and stent cytology

BACKGROUND

Pancreatic and/or biliary (PB) brushing is commonly used to rule out malignant strictures. Many studies have attempted to characterize cytomorphologic characteristics of brushing and stent cytology. However, scant literature exists on the diagnostic implication (DI) of thick extracellular mucin (ECM) indicative of neoplasm in these samples. This study was aimed at reviewing the DI of thick ECM in PB brushing and stent cytology.

METHODS

A retrospective search of consecutive cytologic samples of PB brushings/stents with corresponding surgical pathology or relevant clinical information over a 1-year period was performed. Blinded review of the slides was performed by two cytopathologists. The slides were assessed for the presence, quantity, and quality of ECM. The results were analyzed for statistical significance with the Fisher exact and χ² tests.

RESULTS

One hundred ten cases were identified from 63 patients. Twenty-two cases (20%) were PB brushings only without a prior stent. The remaining 88 cases (80%) had a preexisting stent for symptomatic obstruction. Fourteen of 22 cases (63%) without prior stents and 67 of 88 poststented cases (76%) were nonneoplastic (NN) upon follow-up. ECM was present more frequently in neoplastic cases than in NN cases (p = .03). Among NN cases (n = 87), poststented samples showed more evidence of ECM than prestented samples (15% vs. 45%, p = .045). Identical thick ECM was observed in NN poststent and main-duct intraductal papillary neoplasm samples.

CONCLUSIONS

Although ECM was frequently seen in neoplastic cases, NN cases showed increased evidence of thick ECM among poststented samples. Thick ECM may be common in stent cytology, regardless of the underlying biologic process.

Diagnostic pitfalls and the value of fluorescence in situ hybridization as an adjunct to cytologic evaluation of bile duct brushings in patients with primary sclerosing cholangitis

BACKGROUND

Primary sclerosing cholangitis (PSC) can present diagnostic difficulties on bile duct brushings as cytologic features mimicking adenocarcinoma may exist. This study evaluates the role of fluorescence in-situ hybridization (FISH) as an adjunct to cytologic evaluation.

METHODS

From January 1, 2020, through December 31, 2021, 308 bile duct brushings were processed of which 34 (11%) were malignant, 25 (8%) were suspicious, 36 (12%) were atypical, 204 (66%) were negative and 10 (3%) were nondiagnostic. Follow-up biopsies/resections were performed in the 95 cases with diagnostic cytology (atypical/suspicious/malignant) of which 12 (13%) showed primary sclerosing cholangitis and form the basis of this study. Cytologic, histologic and FISH findings are presented and discussed.

RESULTS

Of the 12 bile duct brushings 4 (34%) were positive/suspicious for adenocarcinoma and 8 (66%) showed atypical epithelial cells. FISH was positive in 2/4 positive/suspicious brushings and negative in the remaining 2 brushings. Histologic findings confirmed the FISH results. The cytologic features of the 2 false positive cases overlapped those of adenocarcinoma. Two of the 8 bile duct brushings with atypical epithelial cells were positive/suspicious for adenocarcinoma on FISH analysis; findings confirmed on histologic follow-up. The remaining 8 patients underwent surveillance for the development of adenocarcinoma with repeat bile duct brushings, FISH analysis and biopsies, each of which has been negative to date.

CONCLUSION

FISH, as an adjunct to the cytologic evaluation of bile duct brushings from patients with PSC, plays a role in improving diagnostic accuracy and serves as a surveillance tool for the potential development of adenocarcinoma.

Molecular features of pancreaticobiliary neoplasms: Implications for diagnosis, prognostication, and therapy selection

BACKGROUND

Molecular diagnostics has impacted the diagnosis, prediction of prognosis, and selection of targeted therapy for many tumor types. While pulmonary adenocarcinomas and melanomas are among the neoplasms most associated with molecular diagnostics and targeted therapy, malignancies of the pancreaticobiliary system have also been impacted by precision medicine.

METHODS

We undertook an electronic search using PubMed and Embase to review the published literature to determine what forms of molecular testing, mutations and oncogenetic pathways are associated with neoplasms of the pancreaticobiliary system. Keywords utilized were pancreas, bile duct, mutations, ERCP, FNA, KRAS, SMAD4, TP53, next-generation sequencing, serous cystadenoma, pancreatic ductal adenocarcinoma, intraductal papillary mucinous neoplasm, cystic mucinous neoplasm, solid pseudo-papillary neoplasm.

RESULTS

A search between 1999 and 2022 yielded 6874 manuscripts. Screening of these yielded 302 more focused manuscripts of which 55 were used for the study. Ductal adenocarcinoma of the pancreas is associated with a progression of mutations beginning wit KRAS mutations and ending with a set of mutations in the TP53, SMAD4, and DPC4 genes. Similar mutations are found in neoplastic mucinous cysts. Specific mutations characterize serous cystadenomas, solid, and pseudo papillary neoplasms and adenocarcinomas of the bile ducts.

CONCLUSIONS

Mutational analysis of cytologic specimens obtained by fine-needle aspiration, and duct brushings and washings are helpful in the diagnosis of pancreaticobiliary neoplasms and may supply prognostic information.

Usefulness of Liquid-Based Cytology in Diagnosing Biliary Tract Cancer Compared to Conventional Smear and Forceps Biopsy

BACKGROUND/AIMS

Liquid-based cytology (LBC) has been shown to improve the diagnostic efficacy of brush cytology for thyroid, cervical and pancreatic cancer. To evaluate the diagnostic performance of LBC for biliary tract cancer, we compared it with conventional smears and forceps biopsies.

METHODS

A retrospective study was conducted of all consecutive patients who underwent brush cytology under ERCP from January 2010 to April 2020. The primary outcome was the diagnostic efficacy of conventional smears and LBC. The difference between the two groups was corrected using inverse probability weighting (IPW). The secondary outcome was the sensitivity and specificity of brush cytology and forceps biopsy. The secondary outcome was evaluated in patients who underwent both methods.

RESULTS

Among 162 patients, conventional smears were performed in 70 patients and LBC was performed in 92 patients. In the primary analysis using IPW, the sensitivity of conventional smears and LBC was 56.00% and 78.26% respectively (P = 0.009). The specificity was 100% for both methods. The accuracy was 66.15% for conventional smears and 83.33% for LBC (P = 0.012). In the secondary analysis, the sensitivity of conventional smears versus forceps biopsies was 62.16% versus 78.38% (P = 0.034) and 81.16% for both LBC and forceps biopsies. The specificity of both cytological examination and forceps biopsies was 100%.

CONCLUSIONS

Liquid-based cytology demonstrated better sensitivity and accuracy than conventional smears. Moreover, its diagnostic performance was close to that of forceps biopsies.

High Diagnostic Yield of Endoscopic Retrograde Cholangiopancreatography Brush Cytology for Indeterminate Strictures

Background

Endoscopic retrograde cholangiopancreatography (ERCP) brush cytology is used frequently for sampling indeterminate biliary strictures. Studies have demonstrated that the diagnostic yield of brush cytology for malignant strictures is estimated to be 6%-70%. With improved diagnostic tools, sampling techniques and specimen processing, the yield of ERCP brush cytology may be higher. This study aimed to assess the yield of brush cytology and determine factors associated with a positive diagnosis.

Methods

This was a cohort study of patients who underwent ERCP brush cytology from October 2017 to May 2020. Patient demographics, clinical, procedural and pathological data were collected using chart review. Sampling data were captured up to 3 months post-index ERCP to capture repeat brushings, biopsies or surgical resections. Outcomes included the diagnostic yield, true/false positive values and true/false negative values of malignancy detection using ERCP brush cytology.

Results

A total of 126 patients underwent a brush cytology, 58% were male and 79% had a stricture in the extrahepatic region. Ninety-three patients were diagnosed with a malignancy, of which 78 had positive brush cytology results and 15 had a negative brush cytology result. The diagnostic yield, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 84%, 83%, 97%, 99%, 68% and 87% respectively.

Conclusion

ERCP brush cytology performed using updated sampling technique is associated with high diagnostic yield. This allows for earlier malignancy diagnosis, timely treatment and decreased need for further investigation.

The Cytomorphologic and Molecular Assessment of Bile Duct Brushing Specimens

Biliary duct brushing cytology is the standard of care for the assessment of bile duct strictures but suffers from low sensitivity for the detection of a high-risk stricture. Pathologic diagnosis of strictures is optimized by integration of cytomorphology and molecular analysis with fluorescence in situ hybridization or next-generation sequencing. Bile duct cancers are genetically heterogeneous, requiring analysis of multiple gene panels to increase sensitivity. Using molecular analysis as an ancillary test for bile duct brushing samples aids in the identification of mutations that support the diagnosis of a high-risk stricture as well as the identification of actionable mutations for targeted therapies currently in clinical trials for the treatment of patients with bile duct cancer.

Cytological Comparison between Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma by Image Analysis Software Using Touch Smear Samples of Surgically Resected Specimens

To investigate useful cytological features for differential diagnosis of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC), this study cytologically compared HCC to ICC using image analysis software. Touch smear specimens of surgically resected specimens were obtained from a total of 61 nodules of HCC and 16 of ICC. The results indicated that the major/minor axis ratio of ICC is significantly larger than that of HCC (1.67 ± 0.27 vs. 1.32 ± 0.11, p < 0.0001) in Papanicolaou staining. This result means that the nucleus of HCC is close to round and the nucleus of ICC is close to an oval. This significant difference in the major/minor axis ratio between ICC and HCC was consistently observed by the same analyses using clinical samples of cytology (4 cases of HCC and 13 cases of ICC) such a fine-needle aspiration, brushing and ascites (ICC: 1.45 ± 0.13 vs. HCC: 1.18 ± 0.056, p = 0.004). We also confirmed that nuclear position center-positioned nucleus (p < 0.0001) and granular cytoplasm (p < 0.0001) are typical features of HCC tumor cells compared to ICC tumor cells. The research study found a significant difference in the nuclear morphology of HCC (round shape) and ICC (oval shape) in Papanicolaou-stained cytology specimens. This simple and objective finding will be very useful for the differential cytodiagnosis of HCC and ICC.

Significance of KRAS mutation testing in biliary brushing cytology specimens: A 10-year retrospective review

BACKGROUND

Biliary strictures can be caused by benign and malignant conditions. A biliary duct brushing diagnosis can be challenging because of low cellularity and overlapping morphology among different entities, leading to a variable reported sensitivity. This study aimed to assess the value of KRAS mutation testing in adding cytological diagnosis of biliary duct brushings.

METHODS

With institutional review board approval, biliary duct brushing cytology specimens were collected from 269 patients with extrahepatic biliary stenosis between August 2011 and July 2021. The results of cytology and KRAS mutational analyses were evaluated in view of corresponding cytology examination and histopathological/clinical follow-up.

RESULTS

KRAS mutations were identified in 50 of 269 biliary stricture brushing cases (19%). Among the cases with available follow-up, 72% (34 of 47) of biliary brushings had confirmed malignancy when there were KRAS mutations. The overall specificity and sensitivity of KRAS mutation testing was 92% and 36%, respectively. KRAS mutation was significantly more enriched in pancreatic duct adenocarcinoma than in cholangiocarcinoma (66% vs 5%, P < .001). The absolute risk of malignancy was 3%, 28%, and 71%, respectively, in negative, atypical, and suspicious cytological diagnostic categories and the risks increased to 14%, 68%, and 95% in corresponding categories with KRAS mutation.

CONCLUSIONS

Our results suggested that KRAS mutational analysis can be considered supplementary to cytology diagnosis of biliary duct brushing for patients with extrahepatic biliary stenosis in clinical practice.

Efficacy of endoscopic samplings during initial biliary drainage for cases of pancreatic head cancer: United diagnostic yields of multiple pathological samplings

BACKGROUND/OBJECTIVES

The diagnostic ability of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) has been fully studied; however, the efficacy of other endoscopic samplings (OESs) is less clear. The aim of this study was to examine the diagnostic efficacies of OESs for pancreatic head cancer (PHC).

METHODS

The diagnostic efficacies of endoscopic samplings were retrospectively analyzed in 448 PHC cases and 63 cases of mass-forming pancreatitis (MFP) during initial transpapillary biliary drainage. The OESs included duodenal biopsy (118 PHCs and 50 MFPs), biliary biopsy (218 and 51) with cytology (368 and 53), and pancreatic duct biopsy (23 and 13) with cytology (56 and 43). EUS-FNA was conducted in a different session (149 and 62). Factors associated with OES sensitivity were analyzed. The sensitivity of biliary biopsy was compared between 1.95 mm and 1.8 mm forceps.

RESULTS

Cancer cells were confirmed in 87.9% of the EUS-FNA samplings and in 64.1% (268/418) obtained by combined OESs (average 1.7 OES types per case): 68.6% by duodenal biopsy, 59.6% by biliary biopsy, 32.6% by biliary cytology, 73.9% by pancreatic duct biopsy, and 33.9% by pancreatic duct cytology. No MFP cases revealed cancer by any sampling. OESs did not increase adverse events. Duodenal stenosis, serum bilirubin, tumor size, and pancreatic juice amounts were associated with OES sensitivity. Biliary biopsy had the same sensitivity with different forceps.

CONCLUSION

EUS-FNA was the most diagnostic protocol; however, OESs can be safely applied during the initial biliary drainage to reduce the demand for EUS-FNA while providing good diagnostic yields.

Diagnostic sensitivity and risk of malignancy for bile duct brushings categorized by the Papanicolaou Society of Cytopathology System for reporting pancreaticobiliary cytopathology

BACKGROUND

The Papanicolaou Society of cytopathology developed a six-category system for pancreaticobiliary cytology specimens. Each category is associated with a definition, diagnostic criteria, estimated risk of malignancy and management recommendations. Risks of malignancy are well defined for specimens obtained by fine-needle aspiration but are less well defined for brushing specimens.

METHODS

Diagnoses of 232 brushing specimens of the pancreatic and bile ducts were correlated with diagnoses from subsequent surgical or cytologic specimens. Sensitivity for the brushing technique was calculated. Risk of malignancy was calculated for each category using the original definitions for nondiagnostic and negative categories and for those of a modified system.

RESULTS

Diagnostic sensitivity was 60%-64%. Risk of malignancy for the nondiagnostic, negative, atypical, suspicious for malignancy, and malignant categories was 28%, 28%, 61%, 91%, and 91%, respectively, when the original category definitions were used.

CONCLUSIONS

Diagnostic sensitivity for duct brushings is low in comparison to fine-needle aspiration. Risk of malignancy is comparable to that of needle aspiration for the negative, atypical and suspicious categories but lower for the malignant category. There is a stepwise increase in malignancy risk as one moves from the negative to the atypical to the suspicious for malignancy categories.

Predicting Malignancy of Biliary Stricture with a Nomogram in Patients with a Non-Malignant Endoscopic Tissue Diagnosis: A Retrospective Study

Purpose

The accurate differentiation between benign and malignant biliary stricture is significant but challenging. Tissue diagnosis of biliary stricture by endoscopy sampling can provide excellent specificity but insufficient sensitivity. For patients with suspected malignant biliary stricture (MBS) but non-malignant was reported in endoscopy tissue samples, we constructed a nomogram to predict malignancy and improve the overall diagnostic performance.

Patients and Methods

232 patients with suspected MBS and underwent endoscopy tissue sampling from January 2017 to December 2019 were included, among which 123 patients’ endoscopy tissue samples were classified as non-malignant (including atypical, negative for malignancy, and nondiagnostic). Demographics, serum markers, radiological and sampling results of these 123 patients were collected to construct a nomogram using multivariate analysis.

Results

The nomogram was developed based on bilirubin, CA19-9, radiological result, and atypical sampling results and provided an AUC of 0.863 (95% CI 0.795–0.930) for predicting MBS. The specificity, sensitivity, and accuracy of endoscopy tissue diagnosis were 100.00%, 59.90%, and 68.53%, respectively. With the nomogram added, the overall diagnosis specificity, sensitivity, and accuracy were 95.24%, 89.20%, and 90.23%, respectively.

Conclusion

The nomogram can predict malignancy in patients whose endoscopy tissue diagnoses were non-malignant. The overall diagnostic performance was improved with the nomogram added.

Predictors of Malignancy in Patients With Indeterminate Biliary Strictures and Atypical Biliary Cytology: Results From Retrospective Cohort Study

Background

Atypical cellular features are commonly encountered in patients with indeterminate biliary strictures, which are nondiagnostic of malignancy yet cannot rule it out. This study aims to identify clinical features that could discriminate patients with indeterminate biliary strictures and atypical biliary cytology who may harbor underlying malignancy.

Methods

All patients with an indeterminate biliary stricture and an atypical brush cytology obtained during endoscopic brushings were identified in a large tertiary-care center. Demographical information, clinical data and the final pathological diagnosis were collected. The study cohort was divided based on the final diagnosis into benign and malignant groups. Descriptive and multivariable analyses were performed.

Results

A total of 151 patients were included in the analysis. Of these, 62.9% were males with mean age of 61.7 ± 16.4 years. Overall, there was an almost equal distribution of patients in the benign and malignant groups. Older age (≥65 years), jaundice, weight loss, intrahepatic biliary and pancreatic duct dilation, double-duct sign and presence of a mass were associated with malignancy in the univariate analysis. However, only older age (odds ratio [OR] 1.02, 95% confidence interval [CI] 1.00 to 1.03), jaundice (OR 3.33, 95% CI 1.11 to 9.98) and presence of a mass (OR 12.10, 95% CI 4.94 to 29.67) were significantly associated with malignancy in the multivariate analysis. High CA19-9 was associated with malignancy only in patients with primary sclerosing cholangitis.

Conclusion

In patients with indeterminate biliary stricture and atypical brush cytology, older age, jaundice and presence of a mass are significant predictors of malignancy. Patients with such characteristics need prompt evaluation to rule out underlying malignancy.

High signal intensity on diffusion-weighted magnetic resonance images is a useful finding for detecting early-stage pancreatic cancer

Purpose

Early detection of pancreatic ductal adenocarcinoma (PDAC) may improve the prognosis. We evaluated novel imaging findings that may contribute to early detection.

Methods

This single-center, retrospective study enrolled 37 patients with a localized main pancreatic duct (MPD) stricture and no obvious pancreatic mass. All patients underwent endoscopic retrograde cholangiopancreatography and brush sampling with cytology and serial pancreatic juice aspiration cytologic examination via endoscopic naso-pancreatic drainage. Patients with cytology-confirmed malignancy underwent surgical resection. The remaining patients were followed by contrast-enhanced computed tomography (CECT), magnetic resonance imaging (MRI), and endoscopic retrograde cholangiopancreatography.

Results

Twenty patients had confirmed malignancy (cancer group) and 17 did not (non-cancer group). Age, MPD stricture location, and PDAC risk factors were similar, but the sex predominance and symptom rate differed between the two groups. In the cancer group, 17 patients were diagnosed by cytology and three by clinical symptoms. CECT, MRI, and endoscopic ultrasonography (EUS) revealed no solid tumors in either group. CECT revealed no significant differences between groups. Diffusion-weighted MRI revealed significant differences in the signal intensity between groups. EUS detected indistinct and small hypoechoic areas in 70% and 41.2% of patients in the cancer and non-cancer groups, respectively. In the cancer group, 11 were diagnosed with cancer at the first indication, and nine were diagnosed at follow-up; the prognosis did not differ between these two subgroups.ss

Conclusions

High signal intensity in diffusion-weighted MRI may be useful for detecting early-stage PDAC and may be an indication for surgical resection even without pathologic confirmation.

Clinical trial registration

The study was a registered at the University Hospital Medical Information Network (UMIN000039623).

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00261-021-03199-1.

Cancer-associated fibroblasts are a useful cytological finding for diagnosing pancreatic ductal adenocarcinoma

INTRODUCTION

Cancer-associated fibroblasts (CAFs) are activated fibroblasts or myofibroblasts that play a crucial role in the invasiveness of pancreatic ductal adenocarcinoma (PDAC). In this study, the cytological features and diagnostic significance of CAFs based on pancreatic duct brushing cytology (PDBC) were evaluated.

METHODS

The prevalence of fibrous stroma (FS) including CAFs on PDBC in 42 PDAC cases and 33 benign cases was retrospectively investigated. The average nuclear size of fibroblasts was compared between PDAC and benign cases to distinguish CAFs from normal FS.

RESULTS

Overall, FS was observed in 25 PDAC cases (60%) and eight benign cases (24%). The average nuclear size of FS in PDAC cases was significantly larger than that in benign cases. From the receiver operating characteristics analysis, the cut-off value of the nuclear size of FS for the diagnosis of PDAC was defined as 10.22 µm. FS with nuclei over 10.22 µm in size in PDAC cases had clear prominent nucleoli. In contrast, FS in benign cases had no clear nucleoli. Thus, CAFs on PDBC were considered to be FS with nuclei over 10.22 µm in size and prominent nucleoli. The presence of CAFs on PDBC had 100% positive predictive value and specificity for the diagnosis of PDAC.

CONCLUSIONS

This study suggested that CAFs on PDBC could be distinguished from normal FS by large nuclear size (over 10.22 µm) and prominent nucleoli and that CAFs on PDBC may be used for the diagnosis of PDAC.

Accuracy of cytopathology evaluation for resected benign and malignant pancreatic disease

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the preferred method for diagnosing pancreatic masses. While the diagnostic success of EUS-FNA is widely accepted, the actual performance of EUS-FNA is not known. This study sought to define the EUS-FNA accuracy compared with the gold standard, surgically resected specimens. The study was a single institution, retrospective, and chart review of patients with surgically resected pancreatic specimens from 2005 to 2015 with a preoperative EUS-FNA or biliary brushing. Cytological reports were organized from least concerning (i.e., low chance of malignancy) to most concerning (high chance of malignancy) into eight cytologic categories. We identified 741 cytologic cases: 530 EUS-FNA and 211 endoscopic brushings. For EUS-FNA samples, 62.5% of "benign" samples proved to be "benign" on surgical pathology. A cytologic diagnosis of "suspicious for malignancy" or "positive for malignancy" were concordant with a cancer diagnosis on surgical pathology 93.3% and 98.0% of cases, respectively. EUS-FNA proved to be highly reliable at diagnosing malignancy for cytologic samples that were "suspicious" or "positive" for malignancy. Paired with supportive clinical data, these interpretations may be used to justify cancer treatment.

Optimal tissue sampling during ERCP and emerging molecular techniques for the differentiation of benign and malignant biliary strictures

Patients with cholangiocarcinoma have poor survival since the majority of patients are diagnosed at a stage precluding surgical resection, due to locally irresectable tumors and/or metastases. Optimization of diagnostic strategies, with a principal role for tissue diagnosis, is essential to detect cancers at an earlier stage amenable to curative treatment. Current barriers for a tissue diagnosis include both insufficient tissue sampling and a difficult cyto- or histopathological assessment. During endoscopic retrograde cholangiopancreatography, optimal brush sampling includes obtaining more than one brush within an individual patient to increase its diagnostic value. Currently, no significant increase of the diagnostic accuracy for the new cytology brush devices aiming to enhance the cellularity of brushings versus standard biliary brush devices has been demonstrated. Peroral cholangioscopy with bile duct biopsies appears to be a valuable tool in the diagnostic work-up of indeterminate biliary strictures, and may overcome current technical difficulties of fluoroscopic-guided biopsies. Over the past years, molecular techniques to detect chromosomal instability, mutations and methylation profiling of tumors have revolutionized, and implementation of these techniques on biliary tissue during diagnostic work-up of biliary strictures may be awaited in the near future. Fluorescence in situ hybridization has already been implemented in routine diagnostic evaluation of biliary strictures in several centers. Next-generation sequencing is promising for standard diagnostic care in biliary strictures, and recent studies have shown adequate detection of prevalent genomic alterations in KRAS, TP53, CDKN2A, SMAD4, PIK3CA, and GNAS on biliary brush material. Detection of DNA methylation of tumor suppressor genes and microRNAs may evolve over the coming years to a valuable diagnostic tool for cholangiocarcinoma. This review summarizes optimal strategies for biliary tissue sampling during endoscopic retrograde cholangiopancreatography and focuses on the evolving molecular techniques on biliary tissue to improve the differentiation of benign and malignant biliary strictures.

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.

The Diagnosis of Autoimmune Pancreatitis Using Endoscopic Ultrasonography

Autoimmune pancreatitis (AIP) is characterized by enlargement of the pancreas and irregular narrowing of the main pancreatic duct. It is often associated with IgG4-related sclerosing cholangitis (IgG4-SC), in which the bile duct narrows. Although characteristic irregular narrowing of the pancreatic duct caused by endoscopic retrograde cholangiopancreatography is noted in AIP, it is difficult to differentiate between localized AIP and pancreatic carcinoma based on imaging of the pancreatic duct. While stenosis of the bile duct in IgG4-SC is characterized by longer-length stenosis than in cholangiocarcinoma, differentiation based on bile duct imaging alone is challenging. Endoscopic ultrasound (EUS) can characterize hypoechoic enlargement of the pancreas or bile duct wall thickening in AIP and IgG4-SC, and diagnosis using elastography and contrast-enhanced EUS are being evaluated. The utility of EUS-guided fine needle aspiration for the histological diagnosis of AIP has been reported and is expected to improve diagnostic performance for AIP. Findings in the bile duct wall from endoscopic retrograde cholangiopancreatography followed by intraductal ultrasonography are useful in differentiating IgG4-SC from cholangiocarcinoma. Diagnoses based on endoscopic ultrasonography play a central role in the diagnosis of AIP.

An assessment of chromosomal alterations detected by fluorescence in situ hybridisation in pancreatobiliary tract malignancy

Background

Using fluorescence in situ hybridisation (FISH) to detect any gain of chromosomes 3, 7, or 17 and loss of the 9p21 locus has been proven to be sensitive in the diagnosis of pancreatobiliary tumors. However, both genetic and environmental factors contribute to the pathogenesis of pancreatobiliary tumors. Therefore, it is unknown whether this method is suitable for Chinese patients with pancreatobiliary tumors. This study aims to compare the sensitivity, specificity, predictive values and accuracy of cytology, ERCP/MRCP and FISH based on Chinese patients with pancreatobiliary tumors,and to analyze differences between brushing-based and formalin-fixed paraffin-embedded (FFPE)-based FISH.

Methods

A total of 66 brush cytology specimens obtained during ERCP were detected by FISH and cytology test respectively to compare the sensitivity, specificity, predictive values and accuracy. Besides, FFPE-based FISH was performed on 46 corresponding paraffin sections of pancreatobiliary tumors obtained by surgical resection.

Results

Our findings demonstrate that FISH greatly improves diagnostic sensitivity and negative predictive value compared to ERCP/MRCP and cytology without much reduction in specificity and positive predictive value. However, our results also indicate that FFPE-based FISH could not effectively identify the false-negative of brushing-based FISH.

Conclusions

We believe that FISH can effectively distinguish true positive and false positive results of cytological or radiological suspicions of malignancy. However, FFPE-based FISH still does not precisely recognize the false-negative of brushing-based FISH. Both cytology-based and PPFE-based FISH had limitation in some specimens.

Tiny but mighty: use of next generation sequencing on discarded cytocentrifuged bile duct brushing specimens to increase sensitivity of cytological diagnosis

Bile duct brushing (BDB) is used to evaluate pancreatobiliary lesions as it widely samples lesions with a low complication rate. Cytological evaluation of BDB is a specific but insensitive test. There is limited literature on the use of post-cytocentrifuged (PCC) samples, which are usually discarded, for next-generation sequencing (NGS) as an adjunct to cytological diagnosis of BDB. In this study we investigate whether molecular analysis by NGS of PCC specimens improves the sensitivity of diagnosis. PCC samples from 100 consecutive BDB specimens spanning 93 unique patients were retained. DNA was extracted and mutational analysis was performed agnostic of morphologic or clinical findings. Each BDB specimen was characterized as negative, atypical or positive based on morphological analysis by trained cytopathologists. Performance characteristics for mutational profiling and morphological analysis were calculated on the basis of clinicopathologic follow-up. There was sufficient clinicopathologic follow-up to classify 94 of 100 cases as either malignant (n = 43) or benign (n = 51). Based on morphologic analysis of cytology, these 94 cases were classified as either benign (n = 55), atypical (n = 18), or as at least suspicious or positive for malignancy (n = 21). Morphologic analysis of cytology showed a sensitivity of 49% and a specificity of 100% if atypical cases were considered negative. NGS revealed oncogenic alterations in 40/43 (93%) of malignant cases based on clinicopathologic follow-up. The most common alterations were in KRAS and TP53, observed in 77% and 49% of malignant cases respectively. No alterations were observed in the 51 benign cases classified based on clinicopathologic follow-up. Supplementing cytomorphologic analysis with molecular profiling of PCC by targeted NGS analysis increased the sensitivity to 93% and maintained specificity at 100%. This study provides evidence for the utility of NGS molecular profiling of PCC specimens to increase the sensitivity of BDB cytology samples, although studies with larger cohorts are needed to verify these findings.

Cytomorphologic characteristics of next-generation sequencing-positive bile duct brushing specimens

INTRODUCTION

Cytology of bile duct brushings (BDBs) is a specific, but insensitive, test for malignancy. Next-generation sequencing (NGS) of BDBs has recently been shown to improve sensitivity. We analyzed the cytologic features of NGS-positive (NGS⁺) and NGS-negative (NGS^-) BDBs and correlated the morphology with the presence of mutations.

MATERIALS AND METHODS

A total of 96 BDBs were analyzed for 29 cytologic features by 2 pathologists who were unaware of the original diagnosis and NGS results. Clinicopathologic follow-up was used to determine the patient outcomes (ie, benign, low-grade neoplasm, malignant [carcinoma/high-grade dysplasia]).

RESULTS

We analyzed 74 NGS⁺ BDBs from 66 patients and 22 NGS^- BDBs from 22 patients. During follow-up, 58 of 66 NGS⁺ patients (88%) had malignancy compared with 0% of NGS^- patients (P < 0.001). Fewer than 50% of the malignant cases had been interpreted as malignant on cytology; however, 100% had demonstrated mutations using NGS. Within the NGS⁺ cases, 53% showed late mutations (TP53, SMAD4, and CDKN2A) supportive of a high-risk stricture. Significant morphologic differences were seen in the background appearance, presence of single cells, architectural disarray, nucleomegaly, anisonucleosis, irregular nuclear borders, increased nuclear/cytoplasmic ratio, nuclear hyperchromasia, nucleoli, abnormal groups, clusters, and/or single cells, and overall impression. Naked nuclei, nucleomegaly, anisonucleosis, and coarse chromatin were more common in BDBs with late mutations than in those with KRAS/GNAS (Kirsten rat sarcoma viral oncogene homolog/guanine nucleotide binding protein, α-stimulating complex locus) mutations only. Cytology had a sensitivity of 16% and a specificity of 100% for malignancy. In contrast, NGS had a sensitivity of 100% and a specificity of 73%. Late mutations were 100% specific for malignancy compared with mutations in KRAS/GNAS only, of which 69% were malignant.

CONCLUSIONS

We found significant overlap in the cytomorphologic features between neoplastic and non-neoplastic BDBs, and more than one half of cancer cases had been interpreted as "nonmalignant" on cytology. NGS showing late mutations was 100% specific for malignancy. Adding genetic testing to BDB cytology would be a valuable ancillary test for the detection of malignancy, and reflex testing should be considered.

Should uncertainty concerning the risk of malignancy be included in diagnostic (nongynecologic) cytopathology reports?

In diagnostic cytology, the known site-specific false positive rates at various anatomical sites for the risk malignancy (ROM) when a confirmed malignant diagnosis is made are comparatively well documented. ROM figures for diagnostic cytology specimens may vary according to the anatomical site of the specimen, the exact nature of the specimen received, the staining method(s) used, and the use of additional laboratory techniques including molecular profiling; furthermore, they often differ to some extent from institution to institution, between differing cytologists within the same institution, and over time. A brief literature review for a selected group of routine diagnostic cytology specimens shows a published ROM for a confirmed malignant diagnosis as follows: bile duct brushings, ~99% (range, 97%-100%); breast fine needle aspiration, 98.5% (range, 92%-100%); serous effusion fluid, 98.9% (range, 90%-100% although lower for squamous cell carcinoma, mesothelioma, and lymphoma), pulmonary endobronchial ultrasound cytology, ~99% (range, 86.6%-100%); thyroid FNA, 98% (range, 97%-99% if NIFTP tumors are excluded), salivary gland FNA, ~90%; (range 57%-100%) and lateral neck cyst FNA, ~99% (range, 95.5%-100%). Because most diagnostic cytology specimens have a small but accepted false-positive rate, this information is vitally important for the clinical management of patients and for shared patient decision making. In our view, the known false-positive rate for a given diagnostic cytology specimen could be included within the cytology report to assist in explaining the limitations of the diagnostic cytology interpretation and help facilitate the clinical decision-making process.

Challenging biliary strictures: pathophysiological features, differential diagnosis, diagnostic algorithms, and new clinically relevant biomarkers - part 1

It is frequently challenging to make the correct diagnosis in patients with biliary strictures. This is particularly important as errors may have disastrous consequences. Benign-appearing strictures treated with stents may later be revealed to be malignant and unnecessary surgery for benign strictures carries a high morbidity rate. In the first part of the review, the essential information that clinicians need to know about diseases responsible for biliary strictures is presented, with a focus on the most recent data. Then, the characteristics and pitfalls of the methods used to make the diagnosis are summarized. These include serum biomarkers, imaging studies, and endoscopic modalities. As tissue diagnosis is the only 100% specific tool, it is described in detail, including techniques for tissue acquisition and their yields, how to prepare samples, and what to expect from the pathologist. Tricks to increase diagnostic yields are described. Clues are then presented for the differential diagnosis between primary and secondary sclerosing cholangitis, IgG4-related sclerosing cholangitis, cholangiocarcinoma, pancreatic cancer, autoimmune pancreatitis, and less frequent diseases. Finally, algorithms that will help to achieve the correct diagnosis are proposed.

Association between chronic pancreatitis and pancreatic cancer: A 10-year retrospective study of endoscopically treated and surgical patients

Pancreatic cancer (PC) has a poor prognosis. Chronic pancreatitis (CP) associates with high morbidity and mortality, and serves as a risk factor for PC. Our study aimed to assess the association between endoscopically treated CP patients and PC, and to establish the rate of CP among patients undergoing surgery for pancreatic ductal adenocarcinoma (PDAC). We retrospectively analyzed 458 CP patients undergoing endoscopic treatment (ET) between 2000 and 2010 and 349 PDAC patients undergoing pancreatic resection between 2000 and 2014 at the Helsinki University Hospital. The likelihood of diagnosing PC was highest within 2 years of a CP diagnosis: 21 of 30 PC diagnoses occurred during this time. After 2 years follow-up: 9 of 30 PC diagnoses occurred 2-12 years from CP diagnosis. Two patients were diagnosed with CP before PDAC. Multivariate analysis showed two prognostic factors indicative of PC development: biliary stricture (HR 9.21; 95% CI 3.76-22.08) and a higher age (per 5-year increases) at CP onset (HR 1.55; 95% CI 1.30-1.85). Among 458 CP patients, the median overall survival without PC was 14.7 years (95% CI 12.0-17.3), falling to 1.6 years (95% CI 1.2-2.0) with PC. The high incidence of PC among CP patients at the beginning of follow-up likely reflected an initially missed PC diagnoses. In long-term follow-up, an increasing PC incidence might reflect the PC-predisposing impact of CP. Thus, we recommend careful follow-up for patients presenting with a recently diagnosed CP and risk factors for PC.

IgG4-related Sclerosing Cholangitis Mimicking Cholangiocarcinoma Diagnosed by Endoscopic Ultrasound-guided Fine-needle Aspiration

A 58-year-old man was referred for obstructive jaundice. Imaging modalities revealed the presence of multiple pancreatic tumors and the stenosis of the middle common bile duct due to a hypoenhanced localized tumor. The multiple pancreatic tumors were histopathologically diagnosed as autoimmune pancreatitis by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). To differentiate between IgG4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma, we diagnosed the biliary tumor as IgG4-SC by EUS-FNA because of insufficient pathological materials obtained in a transpapillary manner. We herein report a case of IgG4-SC diagnosed by EUS-FNA.

Bile duct involvement by hepatocellular carcinoma: A rare occurrence and poor prognostic indicator in bile duct brushing samples

BACKGROUND

Hepatocellular carcinoma (HCC) rarely involves the biliary tree and may be inadvertently sampled on bile duct brushings (BDBs).

METHODS

The pathology archives of 5 institutions were searched for BDBs with HCC involvement.

RESULTS

A total of 17 BDBs from 14 patients were obtained. There was a male:female ratio of 6:1; the median age of the patients was 59.5 years (range, 22-80 years). The median hepatic tumor size was 6.2 cm (range, 2.2-13.0 cm). HCC risk factors included viral hepatitis (5 patients), cirrhosis (5 patients), hemochromatosis (1 patient), and alcoholic steatohepatitis (1 patient). Jaundice with elevated bilirubin, liver enzymes, and α-fetoprotein was common. Endoscopic retrograde cholangiopancreatography demonstrated bile duct dilatation, polypoid intraductal masses (5 samples), clots/debris (2 samples), or strictures (4 samples). All BDBs had single and clustered large cells with naked atypical nuclei, granular cytoplasm, high nuclear/cytoplasmic ratios, and nuclei with prominent macronucleoli. Less common findings included clear/microvesicular cytoplasm (35%), papillae (29%), and anisonucleosis (35%). Classic HCC features (widened trabeculae [35%], endothelial wrapping [24%], multinucleation [24%], and cytoplasmic bile pigment [35%]) were uncommon. A total of 11 BDBs were diagnosed as malignant (10 with HCC and 1 with cholangiocarcinoma), 2 were diagnosed as atypical, and 1 BDB was diagnosed as negative; approximately two-thirds were found to have polysomy on fluorescence in situ hybridization. Approximately 71% of patients died of disease at a median of 3.5 months.

CONCLUSIONS

HCC may extend into the intrahepatic and/or extrahepatic biliary tree, causing masses and/or strictures that may be sampled on BDB. Although cytologically malignant, the classic features of HCC are uncommon, which can cause misdiagnosis. Cytopathologists should be mindful of this differential when evaluating BDBs, particularly when concomitant liver masses and/or HCC risk factors are present. Because of the associated high mortality and rapid rate of death, its presence should be conveyed clearly in pathology reports.

Analysis of microRNA expression in brush cytology specimens improves the diagnosis of pancreatobiliary cancer

BACKGROUND/OBJECTIVES

Malignant pancreatobiliary strictures are in many cases clinically indistinguishable and present a major problem to endoscopy specialists. Intraductal sampling procedures such as brush cytology are commonly used for diagnosis with a sensitivity that is low for a diagnostic test used in daily clinical practice. MicroRNA (miR) alterations detected in many cancers are disease-specific, which can be utilized in clinical applications. The aim of the present study was to analyze whether determination of miR expression levels in intraductal brush cytology specimens is a feasible approach to improve the diagnosis of pancreatobiliary cancer.

METHODS

Brush cytology specimens have been collected during endoscopic retrograde cholangio-pancreatography (ERCP) and analyzed by routine cytology and ancillary miR assays. Total RNA was extracted using the miRNeasy Mini Kit and the expression of miRs frequently dysregulated in pancreatobiliary cancer (miR-16, miR-21, miR-196a, miR-221) were analyzed by quantitative real-time PCR using RNU6B as internal control.

RESULTS

Routine cytology resulted in no false positive diagnoses, however, the combined sensitivity remained at 53.8%. Expression (ΔCt values) of miR-16 (p = 0.0039), miR-196a (p = 0.0003) and miR-221 (p = 0.0049) showed a clear statistical significance between malignant and benign pancreatobiliary specimens (n = 35). Malignancy could be detected combining routine cytology and the miR-196a single marker expression levels with a sensitivity of 84.6% (92.9% in biliary strictures) with no false positives.

CONCLUSIONS

The results offer the first direct demonstration that microRNAs are readily detectable in brush cytology specimens obtained during ERCP, and have the potential to help the cytological diagnosis of pancreatobiliary malignancy.

Microscopic polyangiitis masquerading as a pancreatic neoplasm with multiple lung metastases

A 71-year-old man was admitted to our hospital with right lower abdominal pain. Blood analysis indicated severe inflammation, and abdominal CT revealed a pancreatic head tumour and multiple lung nodules. The level of a tumour marker was high. Pancreatic cancer with multiple lung metastases was suspected; however, because the mass was not detected via endoscopic ultrasonography, it was not biopsied. The serum creatinine level increased rapidly with a urine disorder, and myeloperoxidase-antineutrophil cytoplasmic antibody staining was positive. Severe rapidly progressive glomerulonephritis (RPGN) and microscopic polyangiitis were diagnosed, and high-dose glucocorticoid treatment was started. The patient's high fever returned to normal, and the serum creatinine level declined. Because the RPGN was severe, cyclophosphamide was administrated, and the glucocorticoid was tapered. The pancreatic tumour regressed, the lung nodules disappeared, and the tumour marker level normalised during the treatment. Renal function improved, and maintenance haemodialysis was avoided.

Comparison of liquid-based cytology (CellPrepPlus) and conventional smears in pancreaticobiliary disease

BACKGROUND/AIMS

Endoscopic ultrasound-guided fine needle aspiration (EUSFNA) and brushing cytology are used worldwide to diagnose pancreatic and biliary malignant tumors. Liquid-based cytology (LBC) has been developed and it is currently used to overcome the limitations of conventional smears (CS). In this study, the authors aimed to compare the diagnostic value of the CellPrepPlus (CP; Biodyne) LBC method with CS in samples obtained using EUS-FNA and brushing cytology.

METHODS

This study prospectively enrolled 75 patients with pancreatic or biliary lesions from June 2012 to October 2013. For cytological analyses, including inadequate specimens, benign and atypical were further classified into benign, and suspicious and malignant were subcategorized as malignant. Sensitivity, specificity, accuracy, and positive predictive values (PPV) and negative predictive values (NPV) were evaluated.

RESULTS

In the EUS-FNA based cytological analysis of pancreatic specimens, CP had a sensitivity of 60.7%; specificity, 100%; accuracy, 77.1%; PPV, 100%; and NPV, 64.5%. CS had a sensitivity of 85.7%; specificity, 100%; accuracy, 91.7%; PPV, 100%; and NPV, 83.3%. In the brushing cytology based analysis of biliary specimens, CP had sensitivity of 53.1%; specificity, 100%; accuracy, 54.5%; PPV, 100%; and NPV, 6.3%. CS had a sensitivity of 78.1%; specificity, 100%; accuracy, 78.8%; PPV, 100%; and NPV, 12.5%.

CONCLUSION

Our study found that CP had a lower sensitivity because of low cellularity compared with CS. Therefore, CP (LBC) has a lower diagnostic accuracy for pancreatic EUS-FNA based and biliary brush cytology based analyses compared with CS.

SurePath® LBC improves the diagnostic accuracy of intrahepatic and hilar cholangiocarcinoma

INTRODUCTION

The current study aimed to compare cytology using SurePath^® (SP)-LBC and biliary tissue histology (BTH) for the diagnosis of biliary disease.

METHODS

Between January 2014 and December 2016, 57 patients underwent endoscopic retrograde cholangiopancreatography for the diagnosis of biliary disease. Biliary cytological samples were processed using SP-LBC and subsequently BTH was performed. A final diagnosis was confirmed by surgery (23 malignant cases) and clinical follow-up (34 benign and malignant cases): 18 extrahepatic cholangiocarcinoma; 17 intrahepatic/hilar cholangiocarcinoma (intra/H-CC); eight other malignant disease; and 14 benign biliary disease. The diagnoses made using SP-LBC and BTH were classified into four categories: (1) benign; (2) indeterminate; (3) suspicious for malignancy/malignant; and (4) inadequate. In addition, diagnostic accuracy was compared between SP-LBC and BTH.

RESULTS

Although 23% (13/57) of BTH samples were classified as inadequate, all SP-LBC cases were classified as adequate. Among 43 malignant cases, 11 normal, four indeterminate and 28 suspicious for malignancy/malignant were found using SP-LBC (26%, 9% and 65%, respectively), in contrast to 10 inadequate, nine normal, 10 indeterminate and 14 suspicious for malignancy/malignant observed using BTH (23%, 21%, 23%, and 33%, respectively). The identification of malignant cells was strikingly different between SP-LBC and BTH. Furthermore, limited to intra/H-CC, accuracy was significantly higher using SP-LBC than using BTH (P < .001).

CONCLUSIONS

SP-LBC of the biliary tract is a useful and reliable method for diagnosing biliary malignant disease and has an advantage over BTH for detecting malignant cells and accurately diagnosing intra/H-CC.

Factors Impacting the Performance Characteristics of Bile Duct Brushings: A Clinico-Cytopathologic Analysis of 253 Patients

Context.—

Literature on factors impacting bile duct brushings (BDBs) performance characteristics remain limited.

Objective.—

To capture the current state of daily practice with BDB sign-out.

Design.—

Two hundred fifty-three of 444 BDBs signed out by more than 7 cytopathologists, with histopathologic and/or clinical follow-up of at least 18 months, were examined.

Results.—

One hundred thirty-five of 253 BDBs (53%) had histologically confirmed malignancies, 22 (9%) had cancer-related deaths, and 96 (38%) were benign. Cytologic diagnoses in the 444 BDBs were nondiagnostic (11 [2.5%]), negative (284 [64%]), atypical (62 [13.9%]), suspicious (34 [7.7%]), and malignant (53 [11.9%]). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of malignancy detection were 35%, 100%, 100%, 58%, and 66%, respectively. When atypical, suspicious, and malignant (ASM) categories were combined, sensitivity increased (58%), specificity and PPV dropped (97%), and accuracy increased (73%). Carcinoma type (bile-duct versus pancreatic-ductal) had no effect on accuracy (P = .60) or diagnostic class (P = .84), nor did time of performance (first 7.5 versus latter 7.5 years, P = .13). Interestingly, ThinPrep + cell block (n = 41) had higher sensitivity (61%) and lower specificity (80%) than ThinPrep only (versus 51% and 100%, respectively). Sensitivity and specificity were higher (47% and 100%) in nonstented than stented specimens (59% and 97%). Relative risk of malignancy for “suspicious” (2.30) and “atypical” (2.28) categories was lower but not very different from that of “malignant” category (2.41).

Conclusions.—

Bile duct brushings had fairly low sensitivity but high specificity and PPV with no false positives. Sensitivity almost doubled and specificity dipped minimally when ASM categories were combined, highlighting the need for better classification criteria for atypical/suspicious cases. Higher specificity, PPV, NPV, and accuracy but lower sensitivity in stented BDBs suggest that they be called malignant only when evidence is overwhelmingly convincing.

Endoscopic ultrasound guided brush/fine-needle aspiration cytology: A 15-month study

BACKGROUND

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has become increasingly popular for the diagnosis and staging of gastrointestinal diseases and peri-gastrointestinal lesions. The application of FNA/Brush has dramatically expanded the clinical utility of EUS.

AIMS AND OBJECTIVE

To evaluate the diagnostic accuracy, study the spectrum of lesions encountered in EUS-FNAC/brush cytology of gastrointestinal and peri-gastrointestinal lesions.

MATERIALS AND METHODS

Total of 124 patients during the period from August 2015 to November 2016 was included in the study. Routine staining was done.

RESULTS

A total of 124 cases were studied with 86% (107 cases) being satisfactory for evaluation. M:F ratio was 1:1.03, mean age of 50.5 years. The most common site was common bile duct (CBD) (37%) followed by lymph node (21%), pancreas (17.7%), esophagus (17%), stomach (3.5%), liver (1.8%), gallbladder (1%), and spleen (1%). In total, 53.4% lesions were benign, in 6.5% atypical cells were seen, 12.1% were suspicious for malignancy, and 28% cases were positive for malignancy. Follow-up was available in 102 cases with cyto-histopathological concordance rate of 90%.

CONCLUSION

EUS-FNA/Brush is a reliable, sensitive, specific and minimally invasive way to establish a diagnosis. It can be utilized as a pre-operative procedure for the management of many intra-abdominal lesions and prevent unnecessary invasive procedures.

Comparison of biliary brush biopsy and fine needle biopsy in the diagnosis of biliary strictures

PURPOSE

The purpose of this study is to evaluate the accuracy of percutaneous fine needle biopsy (FNB) and brush biopsy (BB) at a cancer center.

MATERIAL AND METHODS

Retrospective analysis of all bile duct biopsies performed in Interventional Radiology between January 2000 and January 2015 was performed. FNB was performed under real-time cholangiographic guidance using a notched needle directed at the bile duct stricture. BB was performed by advancing a brush across the stricture and moving it back and forth to scrape the stricture. Biopsy results were categorized as true positive (TP), true negative (TN), false positive (FP) and false negative (FN) based on pathology reports and confirmed by surgical specimens or clinical follow-up of at least six months. Fisher's exact test was used to compare the rate of TP in FNB and BB.

RESULTS

One-hundred and nineteen patients underwent FNB or BB. Fifteen were censored because of lack of follow-up. The remaining 104 patients underwent a total of 117 bile duct biopsies during the study period: 34 FNB and 83 BB. There were no complications in either group. In the FNB group 22/34 (64%) biopsies were TP, 4/34(12%) were TN and there were 8(24%) FN biopsies. In the BB group, 20/83 (24%) were TP, 38/83 (46%) TN and 25/83 (30%) FN biopsies. There were no FP biopsies in either group. The sensitivity of detecting malignancy by FNB was significantly higher than that by BB (73% vs 44%, p < .0005). There were no complications associated with FNB or BB.

CONCLUSIONS

FNB of bile duct strictures is safe and has a higher sensitivity for detecting malignancy than BB.

Role of fluorescence in situ hybridization in diagnosing cholangiocarcinoma in indeterminate biliary strictures

BACKGROUND AND AIM

Brush cytology, the conventional method to diagnose cholangiocarcinoma, has been plagued by low diagnostic sensitivity and false-negative results. This paper aims to study the clinical utility of fluorescence in situ hybridization (FISH) in enhancing identification of malignant biliary strictures.

METHODS

Brush cytologic specimens collected from endoscopic retrograde cholangiopancreatography for biliary strictures in a tertiary hospital in Singapore from March 2013 to July 2015 were examined by FISH technique using UroVysion probe set in this study.

RESULTS

Thirty patients were chosen with five patients having multiple FISH performed due to indeterminate results. The diagnoses for biliary strictures were 13 (43.3%) cholangiocarcinomas, seven (23.3%) pancreatic cancers, seven (23.3%) benign biliary strictures, and three (10%) primary sclerosing cholangitis. Conventional brush cytology had sensitivity of 53.8% with specificity of 82.4%. FISH had sensitivity of 30.8% with specificity of 100%. When FISH results were interpreted in cases with negative or atypical brush cytology, two patients had positive FISH results and cholangiocarcinomas. Based on this pilot study, FISH increased sensitivity of brush cytology in detection of cholangiocarcinoma from 53.8% to 69.2% while preserving specificity of 82.4%.

CONCLUSION

Compared with conventional cytology with low sensitivity, FISH may help to increase sensitivity on top of brush cytology while maintaining high specificity.

Diagnostic yield and accuracy of a new cytology brush design compared to standard brush cytology for evaluation of biliary strictures

BACKGROUND

The sensitivity of brush cytology for biliary strictures has typically been low, usually 30%-60%. We compared the cellular yield and diagnostic accuracy using a new cytology brush (n = 16) versus standard biliary brushings (n = 16) in 32 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) with brushings for evaluation of a biliary stricture for malignancy.

METHODS

We performed retrospective chart reviews of 16 consecutive ERCPs with brushings performed for the cytologic evaluation of a biliary stricture for malignancy using the new cytology brush between January 2016 and February 2017 at our institution. Our control cohort was 16 consecutive ERCP cases performed for the same indication directly preceding the availability of the new cytology brush.

RESULTS

The biliary brushing cases performed using the new cytology brush demonstrated a significantly increased number of total cell clusters per representative ×20 field compared with cases using the standard brush (mean 24.6 versus 14.4, P = .03). This trend continued when assessing large (>50 cells) clusters (mean 5.8 vs. 3.3, P = .02) and medium (6-49 cells) clusters (11.1 vs. 5.8, P = .03). Nonetheless, there were no statistically significant differences with regards to diagnostic accuracy for the new cytology brush versus standard biliary brushings.

CONCLUSION

We found that the Infinity brush significantly increased diagnostic yield with regards to total cell clusters, large (>50 cells) clusters, and medium (6-49 cells) clusters, however, this did not lead to increased diagnostic accuracy overall. Further studies of this and other brush designs are warranted to optimize biliary brushing specimens.

Cytologic features of tubular adenoma of ampulla causing distal common bile duct stricture: A case report and review of the literature

Adenomas of the ampulla of Vater are distinctly rare, representing <10% of periampullary neoplasms. Very few reports of the cytologic features of ampullary adenomas are present in literature, particularly in bile duct brushing samples. A case report and review of the literature is presented. The typical cytologic features of ampullary adenomas on cytologic preparations include tall, thin columnar cells with mildly hyperchromatic elongated nuclei and nuclear pseudostratification, in a relatively clean background. The key differential diagnostic entities include invasive adenocarcinoma, thermal artifact, and reactive atypia.

Cytologic predictors of malignancy in bile duct brushings: a multi-reviewer analysis of 60 cases

Diagnosing malignancy in bile duct brushings is highly challenging. Seven reviewers of variable backgrounds and levels of participation in bile duct brushing sign out blindly reviewed 60 specimens (30 malignant with histologic confirmation and 30 benign (15 stented) with resection or ≥18 months of uneventful follow-up), testing the utility of 14 malignant characteristics. Eleven characteristics were statistically significantly associated with malignancy including 3-dimensional clusters (63% in malignant vs 3% in benign, odds ratio 50, P=0.0003), pleomorphism (62 vs 3, odds ratio 48, P=0.0004), 2-cell population (60% vs 3, odds ratio 44, P=0.0005), chromatin pattern (hypo/hyperchromasia) changes (70% vs 7%, odds ratio 33, P<0.0001), high nuclear-to-cytoplasmic ratio (48 vs 3%, odds ratio 27, P=0.0023), cytoplasmic vacuoles (43 vs 3%, odds ratio 22, P=0.0042), nuclear irregularity (70 vs 10%, odds ratio 21, P<0.0001), cellular discohesion (38 vs 3%, odds ratio 18, P=0.0082), hypercellularity (23% vs 0), nuclear molding (20% vs 0) and prominent nucleoli (21% vs 0). Necrosis and infiltrating inflammation were not helpful in identifying malignancy ('neutrophil cannibalism' was noted in 43% malignant); 21/30 (70%) malignant brushings had ≥3 malignant characteristics, while 23 (77%) benign brushings had none. Of 20 brushings with ≥4 characteristics, 1(5%) proved benign and showed detachment atypia, a close malignant mimicker in brushings. Identification of 3 characteristics maximized the combined sensitivity (70%), specificity (97%) and accuracy (83%), but sensitivity dropped as number of characteristics increased. Identification of 3/11 characteristics (3-dimensional clusters, pleomorphism, high nuclear-to-cytoplasmic ratio, nuclear irregularity, hypercellularity, discohesion, chromatin changes, vacuoles, prominent nucleoli, molding and 2-cell population) improves pathologists' overall performance greatly.

The Evolving Role of Pathology in New Developments, Classification, Terminology, and Diagnosis of Pancreatobiliary Neoplasms

Pancreatobiliary tract lesions are increasingly being discovered because of more sensitive imaging modalities. Magnetic resonance imaging has identified incidental pancreatic cysts in 13.5% of patients of progressively increasing age. Pancreatobiliary tissue is more accessible through endoscopic ultrasound and magnetic resonance imaging-guided biopsy procedures, and is now an integral part of pathologists' routine practice. Accordingly, several new tumor categories have been recently recognized, including intraductal tubulopapillary neoplasm, a new addition to tumoral intraepithelial neoplasms. Other entities have been reclassified, including the recent transition to 2-tiered grading of preinvasive neoplasms, as well as new perspectives on the distinctive biologic behavior of oncocytic intraductal papillary mucinous neoplasms (IPMNs) compared with other IPMN subtypes. This has led to proposals for revised staging of virtually every segment of the pancreatobiliary tree, with theranostic markers becoming an integral part of workup. Ki-67 is now an integral part of the classification of neuroendocrine tumors, with new definitions of "high-grade neuroendocrine carcinoma." Although bile duct brushings have opened new avenues for diagnosis, their sensitivity remains low and often requires concomitant fluorescent in situ hybridization to better define ambiguous cases. Various molecular pathways have been elucidated for pancreatic cysts, including KRAS for ductal neoplasia, GNAS for intestinal IPMNs, RNF3 for mucinous cysts, and VHL for serous cystic neoplasms, all key players in diagnostic workup. Integration of these updates into our understanding of pancreatobiliary disease requires active engagement of pathologists for appropriate specimen triage, judicious interpretation of results, and incorporation into reporting and staging. They also provide exciting opportunities for targeted therapy.

Inflammatory Bile Duct Obstruction during the Healing Stage of Severe Acute Pancreatitis

The patient was a 62-year-old woman with a history of severe acute pancreatitis complicated by walled-off necrosis (WON), who developed obstructive jaundice during the recovery phase from WON. Magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP) revealed the complete obstruction of the distal bile duct, and endoscopic ultrasonography (EUS) revealed thickening of the duct wall, with a uniform distribution, and a relatively well-preserved layered structure. A cytopathological examination using ERCP showed no malignancy. The underlying etiology of this case may have been the formation of a cicatricial stricture during the resolution of WON, in addition to fibrosis caused by the spreading of inflammation from pancreatitis.