False-negative rate of endoscopic ultrasound-guided fine-needle aspiration for pancreatic solid and cystic lesions with matched surgical resections as the gold standard: one institution's experience

The Wet Suction Technique Enhances the Diagnostic Efficacy and Aspirate Quality of EUS-FNA for Solid Lesions: A Multicenter Retrospective Study in China

GOALS

To comprehensively compare the wet suction technique with the conventional dry suction technique for endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in solid lesions.

BACKGROUND

Optimal suction techniques for EUS-FNA remain uncertain when approaching solid lesions.

STUDY

We performed a retrospective study of EUS-FNA at 3 medical centers in China. A total of 203 patients were enrolled who received 2 passes of EUS-FNA with 22-G needles. If the first pass underwent dry suction, the second pass was wet suction. Otherwise, the order of suction technique is opposite. Diagnostic accuracy, sample quality (including cellularity and blood contamination), and sample quantity (including specimen adequacy, the maximum intact specimen length, and the total specimen length) were compared between wet-suction and dry-suction techniques.

RESULTS

The patients included 143 pancreatic lesions and 60 nonpancreatic lesions. Compared with the dry suction technique, the wet suction technique yielded a significantly higher diagnostic accuracy (85.22% vs. 72.41%, P =0.002), better specimen adequacy score and cellularity score ( P <0.0001), and lower blood contamination score ( P <0.0001). In the subgroup analysis, wet suction provided significantly higher diagnostic accuracy in pancreatic cancer without chronic pancreatitis ( P <0.05), and better cellularity score and specimen adequacy score, lower blood contamination score, and longer maximum intact specimen length and total specimen length in various lesions than that in dry suction.

CONCLUSIONS

The wet suction technique resulted in significantly higher diagnostic accuracy in pancreatic cancer without chronic pancreatitis, and better cellularity and histologic specimen in most of solid lesions.

Endoscopic ultrasound elastography for malignant pancreatic masses and associated lymph nodes: Critical evaluation of strain ratio cutoff value

BACKGROUND

Endoscopic ultrasound (EUS) can detect small lesions throughout the digestive tract; however, it remains challenging to accurately identify malignancies with this approach. EUS elastography measures tissue hardness, by which malignant and nonmalignant pancreatic masses (PMs) and lymph nodes (LNs) can be differentiated. However, there is currently little information regarding the strain ratio (SR) cutoff in Hispanic populations.

AIM

To determine the diagnostic accuracy of EUS elastography for PMs and LNs with an SR cutoff value in Hispanics.

METHODS

A retrospective study of patients who underwent EUS elastography for PMs between December 2013 and December 2014. A qualitative (analysis of color maps) and quantitative (SR) analysis of PMs and their associated LNs was performed. The accuracy of EUS elastography in identifying malignant PMs and LNs and cutoff value for SR were analyzed. A PM and/or its associated LNs were considered malignant based on histopathological findings from fine-needle aspiration biopsy samples.

RESULTS

A sample of 121 patients was included, 45.4% of whom were female. 69 (57.0%) PMs were histologically malignant, with a median SR of 50.4 vs 33.0 for malignant vs nonmalignant masses (P < 0.001). EUS evaluation identified associated LNs in 43/121 patients (35.5%), in whom 22/43 (51.2%) patients had histologically confirmed malignant diagnosis, with a median SR of 30 vs 40 for malignant vs nonmalignant LNs (P = 0.7182). In detecting malignancy in PMs, an SR cutoff value of > 21.5 yielded a sensitivity of 94.2%, while a cutoff value of > 121 yielded a specificity of 96.2.2%. There were significant differences in the Giovannini scores, a previously established elastic score system, between the patients grouped by their final histology results (P < 0.001). For LNs, SR cutoff values of > 14.0 and > 155 yielded a sensitivity of 90.9% and a specificity of 95.2%, respectively, in detecting malignancy.

CONCLUSION

EUS elastography is a helpful technique for the diagnosis of solid PMs and their associated LNs. The proposed SR cutoff values have a high sensitivity and specificity for the detection of malignancy.

Percutaneous biopsy and drainage of the pancreas

Percutaneous pancreatic interventions performed by abdominal radiologists play important diagnostic and therapeutic roles in the management of a wide range of pancreatic pathology. While often performed with endoscopy, pancreatic mass biopsy obtained via a percutaneous approach may serve as the only feasible option for diagnosis in patients with post-surgical anatomy, severe cardiopulmonary conditions, or prior non-diagnostic endoscopic attempts. Biopsy of pancreatic transplants are commonly performed percutaneously due to inaccessible location of the allograft by endoscopy, usually in the right lower quadrant or pelvis. Percutaneous drainage of collections in acute pancreatitis is primarily indicated for infection with clinical deterioration and may be performed alone or in combination with endoscopic drainage. Post-surgical pancreatic collections related to pancreatic duct fistula or leak also often warrant therapeutic percutaneous drainage. Knowledge of appropriate indications, strategies of approach, technique, and complications associated with these procedures is critical for a successful clinical practice.

Cytologic Categorization with Risk Stratification of Endoscopic Ultrasound-Guided Fine Needle Aspiration from Pancreatic Lesions Based on Guidelines of the Papanicolaou Society of Cytopathology: 12-Year Tertiary Care Experience

BACKGROUND AND AIMS: Pancreatic malignancy is an important cause of cancer mortality worldwide. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) plays a crucial role in the pre-operative diagnosis of pancreatic lesions. In this study, we have analyzed the cytological spectrum of pancreatic lesions in the Indian population over 12 years, categorized them according to the Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology (PSCPC), and assessed the risk of malignancy (ROM) for each of the categories. METHODS: A computerized data search from January 2008 to December 2019 revealed 581 pancreatic EUS-FNA samples, among which surgical follow-up was available for 73 cases. All cytological specimens were reviewed and prospectively classified into one of the six diagnostic categories proposed by the PSCPC. Subsequently, a cytohistological correlation was performed and the ROM was calculated for each category. RESULTS: The cytologic diagnoses included 50 nondiagnostic (category I), 175 negative for malignancy (category II), 19 atypical (category III), 27 neoplastic:benign (category IVA), 30 neoplastic:other (category IVB), 26 suspicious (category V), and 254 malignant (category VI) cases. ROM for non-diagnostic aspirates, nonneoplastic benign specimens, atypical cases, neoplastic:benign, neoplastic:other, suspicious for malignancy, and the malignant category was 16.7%, 7.1%, 33.3%, 0.0%, 20.0%, 100%, and 78.6%, respectively. CONCLUSION: We document an increased risk of malignancy from category I to category VI of the PSCPC. The malignancy risk for category VI (malignant) was statistically significant in our study but was lower in comparison to the values reported by other authors. Nonetheless, such an approach would establish transparent communication between the pathologist and the clinician, as well as aid the clinician in decision making, particularly in intermediate categories.

Comparison between modified wet suction and dry suction technique for endoscopic ultrasound-guided fine-needle biopsy in pancreatic solid lesions

BACKGROUND AND AIM

Although endoscopic ultrasound-guided fine-needle biopsy is widely applied, there is no clear consensus on the optimal biopsy technique. We described a modified wet suction technique (MWEST) with the aim to compare the efficacy and safety between MWEST and the dry suction technique (DST).

METHODS

In this prospective, randomized, crossover, single-blinded study, patients with suspected pancreatic malignancy were randomized to the DST (group A) or MWEST (group B) for the first pass, and the two techniques were performed alternately. The primary outcome was the comparison of specimen adequacy and diagnostic yield between the techniques. Secondary outcomes included the macroscopic visible core length, blood contamination of specimens, and adverse events of both techniques.

RESULTS

From January 2019 to September 2019, 216 passes were performed in 50 patients. The specimen adequacy was significantly higher in "per-lesion" (P = 0.026), "per-pass" (cytology: P = 0.034; histology: P = 0.042), and first-pass analysis (P = 0.034) for MWEST than for DST. In diagnostic yield, MWEST showed significantly superior histological yield (P = 0.014) and first-pass analysis (κ: MWEST: 0.743 and DST: 0.519) compared with DST. The median macroscopic visible core lengths were 8 mm (interquartile range: 3.25-15 mm) and 10 mm (interquartile range: 5.25-15 mm) for DST and MWEST, respectively (P = 0.036). Blood contamination was significantly more serious in DST than in MWEST (cytology: P = 0.021; histology: P = 0.042).

CONCLUSIONS

Endoscopic ultrasound-guided fine-needle biopsy with MWEST resulted in significantly better quality of specimen, histological, and first-pass diagnostic yields and comparable safety compared with the DST. MWEST is preferred for endoscopic ultrasound-guided fine-needle biopsy in pancreatic solid lesions.

Efficacy of EUS-guided needle-based confocal laser endomicroscopy in the diagnosis of pancreatic lesions: A systematic review and meta-analysis

Background and Objectives:

Needle-based confocal laser endomicroscopy (nCLE) is a procedure in which an AQ-Flex nCLE mini-probe is passed through an EUS-FNA needle into a pancreatic lesion to enable subsurface in vivo tissue analysis. In this study, we conducted a systematic review and meta-analysis of nCLE for the diagnosis of pancreatic lesions.

Materials and Methods:

We conducted a comprehensive search of several databases and conference proceedings, including PubMed, EMBASE, Google-Scholar, MEDLINE, SCOPUS, and Web of Science databases (earliest inception to March 2020). The primary outcomes assessed the pooled rate of diagnostic accuracy for nCLE and the secondary outcomes assessed the pooled rate of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and adverse events (AE) of nCLE to diagnose premalignant/malignant pancreatic lesions.

Results:

Eleven studies on 443 patients were included in our analysis. The pooled rate of diagnostic accuracy of EUS nCLE was 83% (95 confidence interval [CI] = 79–87; I² = 0). The pooled rate of sensitivity, specificity, PPV and NPV of EUS nCLE was 85.29% (95% CI = 76.9–93.68; I² = 85%), 90.49% (95% CI = 82.24–98.74; I² = 64%), 94.15% (95% CI = 88.55–99.76; I² = 68%), and 73.44% (95% CI = 60.16–86.72; I² = 93%), respectively. The total AE rate was 5.41% (±5.92) with postprocedure pancreatitis being the most common AE at 2.28% (±3.73).

Conclusion:

In summary, this study highlights the rate of diagnostic accuracy, sensitivity, specificity, and PPV for distinguishing premalignant/malignant lesions. Pancreatic lesions need to be further defined with more validation studies to characterize CLE diagnosis criteria and to evaluate its use as an adjunct to EUS-FNA.

The benefits of the Papanicolaou Society of Cytopathology System for reporting pancreatobiliary cytology: A 2-year review from a single academic institution

OBJECTIVE

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an essential tool in the diagnosis of pancreatic lesions. The aim of this study was to evaluate the diagnostic accuracy of cytology from EUS-FNA, to correlate the results with the corresponding histopathological diagnoses and to analyse the impact of retrospective assignment of the Papanicolaou Society of Cytopathology (PSC) reporting system categories.

METHODS

All pancreatic FNA specimens reported at the Royal Free Hospital during a 2-year period were retrospectively collected and assigned to the PSC system categories. Any available corresponding histological samples were assessed for concordance.

RESULTS

In total, 236 cytology specimens from 223 patients were identified, of which 108 (45.8%) had corresponding histology samples. The main reason for cyto-histological discrepancy was sampling error. Interpretive error was identified in one case. Overall, sensitivity was 92.5%, specificity was 100%, diagnostic accuracy of cytology was 95%, false-positive rate was 0% and false-negative rate was 7.5%. The implementation of the new reporting system reduced the number of cases in the atypical category. All cases previously categorised as suspicious or malignant remained in the same category.

CONCLUSIONS

EUS-FNA is an accurate method for evaluating pancreatobiliary lesions. The implementation of the Papanicolaou Society of Cytopathology diagnostic system enhances standardisation of the reporting terminology and reduces the number of samples in the non-standardised and equivocal atypical category.

Next-generation sequencing of residual cytologic fixative preserved DNA from pancreatic lesions: A pilot study

BACKGROUND

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a sensitive and specific tool in the risk stratification of pancreatic lesions, including cysts. The sensitivity and specificity of EUS-FNA has been shown to improve when cytology is combined with next-generation sequencing (NGS). Ideally, fresh cyst fluid is used for NGS. In this pilot study, we explore the possibility of sequencing DNA derived from residual alcohol-fixed pancreatic aspirates.

METHODS

Residual cytologic fixatives (n = 42) from 39 patients who underwent EUS-FNA for pancreatic lesions were collected along with demographics, imaging, and laboratory studies. Samples were designated as nonneoplastic/nonmucinous benign (NB), mucinous cyst (MC), pancreatic ductal adenocarcinoma (PDAC), or well-differentiated neuroendocrine tumor (NET) on the basis of cytopathologic evaluation and sequenced on the Oncomine platform (ThermoFisher Scientific, Waltham, Massachusetts).

RESULTS

Ten of 14 (71.4%) MCs exhibited clinically significant variants, including KRAS, GNAS, and TP53. Ten of 15 (66.7%) PDACs had KRAS alterations, and 9 of 15 (60%) showed variants in TP53. No variants were detected in any NETs. Only 1 of 9 (11.1%) NB aspirates showed variants in KRAS and MAP2K. Sequencing of formalin-fixed, paraffin-embedded tissue revealed variants identical to those detected in fixative-derived DNA in 4 of 5 cases (80%).

CONCLUSION

Residual DNA from alcohol-fixed aspirates are an underutilized source for NGS. Sequencing residual fixative-derived DNA has the potential to be integrated into the workup of pancreatic aspirates, possibly impacting management.

Marker Identification of the Grade of Dysplasia of Intraductal Papillary Mucinous Neoplasm in Pancreatic Cyst Fluid by Quantitative Proteomic Profiling

The incidence of patients with pancreatic cystic lesions, particularly intraductal papillary mucinous neoplasm (IPMN), is increasing. Current guidelines, which primarily consider radiological features and laboratory data, have had limited success in predicting malignant IPMN. The lack of a definitive diagnostic method has led to low-risk IPMN patients undergoing unnecessary surgeries. To address this issue, we discovered IPMN marker candidates by analyzing pancreatic cystic fluid by mass spectrometry. A total of 30 cyst fluid samples, comprising IPMN dysplasia and other cystic lesions, were evaluated. Mucus was removed by brief sonication, and the resulting supernatant was subjected to filter-aided sample preparation and high-pH peptide fractionation. Subsequently, the samples were analyzed by LC-MS/MS. Using several bioinformatics tools, such as gene ontology and ingenuity pathway analysis, we detailed IPMNs at the molecular level. Among the 5834 proteins identified in our dataset, 364 proteins were differentially expressed between IPMN dysplasia. The 19 final candidates consistently increased or decreased with greater IPMN malignancy. CD55 was validated in an independent cohort by ELISA, Western blot, and IHC, and the results were consistent with the MS data. In summary, we have determined the characteristics of pancreatic cyst fluid proteins and discovered potential biomarkers for IPMN dysplasia.

Comparison of smear cytology and liquid-based cytology in EUS-guided FNA of pancreatic lesions: experience from a large tertiary center

BACKGROUND AND AIMS

Studies comparing the diagnostic efficacy of liquid-based cytology (LBC) and smear cytology (SC) of pancreatic tissue sampling obtained via EUS-guided FNA (EUS-FNA) are still insufficient, mainly because results were controversial. We compared the diagnostic efficiency of LBC and SC of EUS-FNA of pancreatic lesions in one of the largest tertiary hospitals in China.

METHODS

A retrospective database search (January 2015 to January 2019) was performed for patients who underwent EUS-FNA with both LBC and SC. Demographic, cytologic, and endosonographic data were collected from 819 patients; 514 cases met the inclusion criteria. Diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were compared. Rapid on-site evaluation was not available in all cases.

RESULTS

Three hundred eighty-five cases (74.90%) had confirmed malignancy, and 40 cases (7.78%) confirmed benign neoplasm. Adequate tissue sampling rates showed no significant difference between the 2 groups. The sensitivity, accuracy, and negative predictive value (NPV) of LBC were higher than those of SC with statistical significance (71.4% vs 55.1%, 76.1% vs 61.6%, and 40.6% vs 27.7%, respectively). The sensitivity, accuracy, and NPV of combined SC and LBC were higher than those of LBC alone with statistical significance (83.9% vs 71.4%, 86.5% vs 76.1%, and 56.8% vs 40.6%, respectively). Multivariate analysis revealed that pancreatic neck/body/tail lesions (P = .003), solid lesions (P < .001), 22-gauge needle size (P < .001), and number of needle passage >3 (P = .041) were associated with higher diagnostic sensitivity in all participants using LBC, whereas number of needle passage >3 (P = .017) was associated with higher diagnostic sensitivity using SC.

CONCLUSIONS

LBC was more accurate and sensitive than SC in EUS-FNA of pancreatic lesions with higher NPV when rapid on-site evaluation is unavailable. Pancreatic neck/body/tail lesions, solid lesions, 22-gauge needle, and more than 3 passes were associated with higher sensitivity when using LBC. Performing more than 3 passes is associated with higher sensitivity when using SC.

Novel Methylated DNA Markers Discriminate Advanced Neoplasia in Pancreatic Cysts: Marker Discovery, Tissue Validation, and Cyst Fluid Testing

OBJECTIVES

Pancreatic cystic lesions (PCLs) may be precancerous. Those likely to harbor high-grade dysplasia (HGD) or pancreatic cancer (PC) are targets for surgical resection. Current algorithms to predict advanced neoplasia (HGD/PC) in PCLs lack diagnostic accuracy. In pancreatic tissue and cyst fluid (CF) from PCLs, we sought to identify and validate novel methylated DNA markers (MDMs) that discriminate HGD/PC from low-grade dysplasia (LGD) or no dysplasia (ND).

METHODS

From an unbiased whole-methylome discovery approach using predefined selection criteria followed by multistep validation on case (HGD or PC) and control (ND or LGD) tissues, we identified discriminant MDMs. Top candidate MDMs were then assayed by quantitative methylation-specific polymerase chain reaction on archival CF from surgically resected PCLs.

RESULTS

Of 25 discriminant MDMs identified in tissue, 13 were selected for validation in 134 CF samples (21 cases [8 HGD, 13 PC], 113 controls [45 ND, 68 LGD]). A tree-based algorithm using 2 CF-MDMs (TBX15, BMP3) achieved sensitivity and specificity above 90%. Discrimination was significantly better by this CF-MDM panel than by mutant KRAS or carcinoembryonic antigen, with areas under the receiver operating characteristic curve of 0.93 (95% confidence interval: 0.86-0.99), 0.71 (0.57-0.85), and 0.72 (0.60-0.84), respectively. Cutoffs for the MDM panel applied to an independent CF validation set (31 cases, 56 controls) yielded similarly high discrimination, areas under the receiver operating characteristic curve = 0.86 (95% confidence interval: 0.77-0.94, P = 0.2).

DISCUSSION

Novel MDMs discovered and validated in tissue accurately identify PCLs harboring HGD/PC. A panel of 2 MDMs assayed in CF yielded results with potential to enhance current risk prediction algorithms. Prospective studies are indicated to optimize and further evaluate CF-MDMs for clinical use.

Risk of malignancy in the categories of the Papanicolaou Society of Cytopathology system for reporting pancreaticobiliary cytology

BACKGROUND

Management of pancreatic lesions depends on the risk of malignancy, which is primarily determined from the cytologic and radiologic evaluation findings. The Papanicolaou Society of Cytopathology (PSC) published a classification system for reporting pancreaticobiliary cytology. However, the "neoplastic: other" category can be further stratified by high-grade atypia (HGA). Studies on the risk of malignancy using the PSC system have been limited.

MATERIALS AND METHODS

All patients who had undergone endoscopic ultrasound-guided fine-needle aspiration (FNA) for a pancreatic lesion at Massachusetts General Hospital from January 2016 to December 2016 were prospectively classified. The clinical, radiographic, and endoscopic findings, cytologic and histologic diagnoses, and follow-up data from 334 FNA biopsies from 322 patients were reviewed. The neoplastic: other category was subclassified as low-grade atypia or HGA. The absolute risk of malignancy was determined by the histologic outcome or follow-up of ≥6 months.

RESULTS

The absolute risk of malignancy was 7.7% for the nondiagnostic category; 1.0% for negative; 28.0% for atypical; 0.0% for neoplastic: benign; 30.3% for neoplastic: other; 90.0% for neoplastic: other with HGA; 100% for suspicious; and 100% for positive. When the neoplastic: other with HGA, suspicious, and positive cytologic diagnoses were considered positive, the sensitivity, specificity, positive predictive value, and negative predictive value for pancreatic FNA biopsy was 92.2%, 98.8%, 98.3%, and 94.3%, respectively.

CONCLUSIONS

Categories of the PSC system each carry an implied absolute risk of malignancy, increasing from the negative to positive categories. The presence of HGA identifies lesions at the greatest risk of malignancy in the neoplastic: other category, and its inclusion with suspicious and positive as positive diagnoses optimizes the diagnostic performance of identifying high-risk lesions that warrant surgical excision.

Recent advancement in EUS-guided fine needle sampling

EUS-guided tissue acquisition technique plays an essential role for evaluation of gastrointestinal tumors. Several components affect the yield of EUS-guided tissue acquisition outcomes such as sampling techniques, use of ROSE (rapid onsite evaluation), training and experience, and needle designs. In this review we discuss advancement in EUS-guided fine needle sampling.

Death within 30 days of fine needle aspiration: Post-mortem confirmation of FNA diagnoses and the contribution of FNA to patient mortality

BACKGROUND

Fine needle aspiration (FNA) diagnoses are usually confirmed via surgical pathology or via evaluation of clinical outcomes. However, such confirmation may not occur for patients who die shortly after FNA, and autopsy may be a useful quality assessment tool in these cases. Also, there is little data investigating the relationship between FNA and mortality. We sought to demonstrate the autopsy as a quality assessment tool for the FNA and assess the contribution of FNA to mortality in patients who die soon after the procedure.

METHODS

A search of our database was performed from 1992 to 2016 for patients who were autopsied after dying within 30 d of an FNA. Concordance between findings from FNA, autopsy, and any intervening surgical pathology material was determined. Finally, a subjective determination of the likelihood that FNAs contributed to deaths was made by reviewing autopsy reports. The contribution was categorised as either "unlikely", "possible", or "probable".

RESULTS

Fifty-eight patients (average age = 58 y) met the search criteria. Thirty-six (62%) patients had malignancies. Surgical pathology material was obtained concurrently or following FNA in 20 cases (34%). There was 73% concordance between FNA and autopsy findings, which compares to 80% concordance between FNA and surgical pathology diagnoses. The FNA was determined to be at least possibly contributory to death in 7/58 cases (3 cases designated as "probable," and 4 as "possible").

CONCLUSION

Autopsy can be used to validate FNA diagnoses and, like surgical pathology, confirms that FNA diagnoses are mostly accurate. However, in a small number of patients, FNA can precipitate death.

Reclassification of lesions in biopsies by fine-needle aspiration of pancreas and biliary tree using Papanicolaou classification

BACKGROUND

Our aim was to evaluate the application of the classification of the Papanicolaou Cytopathology Society for the report of biopsies by fine-needle aspiration (FNA) of pancreas and bile duct.

METHODS

The FNAs obtained consecutively during 1 year were analyzed. Descriptive statistics were performed and sensitivity, specificity, positive predictive value, negative predictive value, and cytohistological correlation were determined. The reference standard test was the histopathological study.

RESULTS

A total of 134 cases of FNA were reclassified with ultrasound guidance according to the classification of the Papanicolaou Society, the median age was 59 years (range, 25-80 years). A case interpreted as non-diagnostic was reclassified to category 4 and 3 cases with atypical cells were reclassified to category 5. All malignant cases remained unchanged. Surgical follow-up was performed in 35 patients (26.1%), with a cytohistological concordance in 21 cases (91.3%) and 2 discordant cases (8.7%), the reasons for the discrepancy were due to sampling error, one of them with scarce material to make a diagnosis of higher category, the other case with partial agreement, because cytology was observed atypical cylindrical epithelium, with histology of grade 2 neuroendocrine neoplasia and low grade mucinous intraepithelial neoplasia. In general, the sensitivity and specificity were 100% and 75% respectively, the positive predictive value 88% and the negative predictive value 100%.

CONCLUSIONS

The FNA guided with endoscopic ultrasound (EUS) and interpreted according to the Papanicolaou Cytopathology Society Classification is an accurate method to evaluate pancreatic and biliary tract lesions with a high positive predictive value of 88%.

Diagnosis of intraductal papillary mucinous neoplasm using endoscopic ultrasound guided microbiopsies: A case report

Pancreatic cysts are increasingly diagnosed due to expanding use of cross-sectional imaging, but current diagnostic modalities have limited diagnostic accuracy. Recently, a novel through-the-needle microbiopsy forceps has become available, offering the possibility of obtaining cyst-wall biopsies. We present a case of 41-year-old male with chronic pancreatitis and a 2-cm pancreatic cyst, initially considered a pseudocyst. Subsequently, endoscopic ultrasound guided microbiopsies were successfully obtained, which surprisingly revealed an intraductal papillary mucinous neoplasm of mixed subtype with low grade dysplasia. In conclusion, obtaining biopsies from the wall of the pancreatic cystic lesions with this novel instrument is feasible and, as demonstrated in this case, can possibly alter the clinical outcome. Microbiopsies offered enough cellular material, allowing supplemental gene mutation analysis, which combined with other modalities could lead to a more individual approach when treating pancreatic cysts. However, prospective studies are warranted before routine clinical implementation.

Feasibility and safety of microforceps biopsy in the diagnosis of pancreatic cysts

BACKGROUND AND AIMS

The tissue acquisition and diagnostic yield of cyst fluid cytology is low-to-moderate and rarely provides a specific diagnosis. The aim of this study was to compare the tissue acquisition and diagnostic tissue yield of microforceps biopsy (MFB) with cyst fluid cytology.

METHODS

In this multicenter study, data of 42 patients who had cysts both aspirated by EUS-guided FNA (EUS-FNA) and biopsy specimens were then obtained with an MFB device, were collected. Cytology analysis of cyst fluid and histologic analysis of biopsy specimens were done. Acquisition yield was defined as percentage of patients with tissue present in the aspirate or biopsy. Diagnostic tissue yield was evaluated at 3 levels: the ability of differentiation between mucinous and/or nonmucinous cysts, detection of high risk for malignancy, and specific cyst type diagnosis.

RESULTS

The mean patient age was 69 years. Sixteen pancreatic cysts (38.1%) were located in the head, 17 (40.5%) in the body, and 9 (21.4%) in the tail. The mean cyst size was 28.2 mm (12-60 mm); 25 of 42 (60%) were septated. The EUS-FNA tissue (fluid) acquisition yield was 88.1% (37/42). The MFB tissue acquisition yield was 90.4% (38/42). The diagnostic cytology yield to differentiate between mucinous and/or nonmucinous cysts was 47.6% (20/42), and the MFB histologic yield to differentiate between mucinous and/or nonmucinous cysts was 61.9% (26/42) (P = .188). The percentage of cysts at high risk for malignancy by cytology was 54.7% (23/42), and MFB was 71.5% (30/42) (P = .113). However, the ability of MFB to provide a specific cyst type diagnosis was 35.7% (15/42), and that for cytology was 4.8% (2/42) (P = .001). Surgical histology was concordant with that of MFB in 6 of 7 patients (85%), and with that of cytology in 1 of 7 patients (15%).

CONCLUSION

The cyst tissue acquisition yield for MFBs was 90%. Although cytology of cyst fluid and MFB were comparable in distinguishing mucinous and nonmucinous cysts and detecting cysts at high risk for malignancy, MFB was far superior to cytology for providing a specific cyst diagnosis.

Quantitative proteomic analysis of pancreatic cyst fluid proteins associated with malignancy in intraductal papillary mucinous neoplasms

Background

The application of advanced imaging technologies for identifying pancreatic cysts has become widespread. However, accurately differentiating between low-grade dysplasia (LGD), high-grade dysplasia (HGD), and invasive intraductal papillary mucinous neoplasms (IPMNs) remains a diagnostic challenge with current biomarkers, necessitating the development of novel biomarkers that can distinguish IPMN malignancy.

Methods

Cyst fluid samples were collected from nine IPMN patients (3 LGD, 3 HGD, and 3 invasive IPMN) during their pancreatectomies. An integrated proteomics approach that combines filter-aided sample preparation, stage tip-based high-pH fractionation, and high-resolution MS was applied to acquire in-depth proteomic data of pancreatic cyst fluid and discover marker candidates for IPMN malignancy. Biological processes of differentially expressed proteins that are related to pancreatic cysts and aggressive malignancy were analyzed using bioinformatics tools such as gene ontology analysis and Ingenuity pathway analysis. In order to confirm the validity of the marker candidates, 19 cyst fluid samples were analyzed by western blot.

Results

A dataset of 2992 proteins was constructed from pancreatic cyst fluid samples. A subsequent analysis found 2963 identified proteins in individual samples, 2837 of which were quantifiable. Differentially expressed proteins between histological grades of IPMN were associated with pancreatic diseases and malignancy according to ingenuity pathway analysis. Eighteen biomarker candidates that were differentially expressed across IPMN histological grades were discovered—7 DEPs that were upregulated and 11 that were downregulated in more malignant grades. HOOK1 and PTPN6 were validated by western blot in an independent cohort, the results of which were consistent with our proteomic data.

Conclusions

This study demonstrates that novel biomarker candidates for IPMN malignancy can be discovered through proteomic analysis of pancreatic cyst fluid.

Electronic supplementary material

The online version of this article (10.1186/s12014-018-9193-1) contains supplementary material, which is available to authorized users.

Advanced EUS Guided Tissue Acquisition Methods for Pancreatic Cancer

Pancreas cancer is a lethal cancer as the majority patients are diagnosed at an advanced incurable stage. Despite improvements in diagnostic modalities and management strategies, including surgery and chemotherapies, the outcome of pancreas cancer remains poor. Endoscopic ultrasound (EUS) is an important imaging tool for pancreas cancer. For decades, resected pancreas cancer and other cancer specimens have been used to identify tissue biomarkers or genomics for precision therapy; however, only 20% of patients undergo surgery, and thus, this framework is not useful for unresectable pancreas cancer. With advancements in needle technologies, tumor specimens can be obtained at the time of tissue diagnosis. Tumor tissue can be used for development of personalized cancer treatment, such as performing whole exome sequencing and global genomic profiling of pancreas cancer, development of tissue biomarkers, and targeted mutational assays for precise chemotherapy treatment. In this review, we discuss the recent advances in tissue acquisition of pancreas cancer.

Diagnostic value of targeted next-generation sequencing in patients with suspected pancreatic or periampullary cancer

Aims

Radiological imaging and morphological assessment of cytology material have limitations for preoperative classification of pancreatic or periampullary lesions, often resulting in surgical resection without definitive diagnosis. Our prospective study aims to define the diagnostic value of targeted next-generation sequencing (NGS) of DNA from cytology material.

Methods

Patients with a suspect pancreatic or periampullary lesion underwent standard diagnostic evaluation including preoperative morphological cytology assessment. Treatment options for suspect lesions were surgical exploration with possible resection, follow-up or palliation. The cytology samples were analysed with NGS, in which 50 genes were sequenced for the presence of pathogenic variants. The NGS results were integrated with the clinical information during multidisciplinary team meetings, and changes in the treatment plan were scored. Diagnostic accuracy of NGS analysis (malignancy vs benign disease) was calculated.

Results

NGS results of the cytology samples were confirmed in the resection specimens of the first 10 included patients. The integration of the NGS results led to a change in treatment plan in 7 out of 70 patients (from exploration to follow-up, n=4; from follow-up to exploration and resection, n=2; from palliation to resection, n=1). In four patients, the NGS results were contradictory, but did not affect the treatment plan. In the remaining 59 patients, NGS analysis supported the initial treatment plan. The diagnostic accuracy of NGS analysis was 94% (sensitivity=93%; specificity=100%).

Conclusions

NGS can change the treatment plan in a significant portion of patients with suspect pancreatic or periampullary lesions. Application of NGS can optimise treatment selection and diminish unnecessary surgeries.

Imaging modalities for characterising focal pancreatic lesions

BACKGROUND

Increasing numbers of incidental pancreatic lesions are being detected each year. Accurate characterisation of pancreatic lesions into benign, precancerous, and cancer masses is crucial in deciding whether to use treatment or surveillance. Distinguishing benign lesions from precancerous and cancerous lesions can prevent patients from undergoing unnecessary major surgery. Despite the importance of accurately classifying pancreatic lesions, there is no clear algorithm for management of focal pancreatic lesions.

OBJECTIVES

To determine and compare the diagnostic accuracy of various imaging modalities in detecting cancerous and precancerous lesions in people with focal pancreatic lesions.

SEARCH METHODS

We searched the CENTRAL, MEDLINE, Embase, and Science Citation Index until 19 July 2016. We searched the references of included studies to identify further studies. We did not restrict studies based on language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We planned to include studies reporting cross-sectional information on the index test (CT (computed tomography), MRI (magnetic resonance imaging), PET (positron emission tomography), EUS (endoscopic ultrasound), EUS elastography, and EUS-guided biopsy or FNA (fine-needle aspiration)) and reference standard (confirmation of the nature of the lesion was obtained by histopathological examination of the entire lesion by surgical excision, or histopathological examination for confirmation of precancer or cancer by biopsy and clinical follow-up of at least six months in people with negative index tests) in people with pancreatic lesions irrespective of language or publication status or whether the data were collected prospectively or retrospectively.

DATA COLLECTION AND ANALYSIS

Two review authors independently searched the references to identify relevant studies and extracted the data. We planned to use the bivariate analysis to calculate the summary sensitivity and specificity with their 95% confidence intervals and the hierarchical summary receiver operating characteristic (HSROC) to compare the tests and assess heterogeneity, but used simpler models (such as univariate random-effects model and univariate fixed-effect model) for combining studies when appropriate because of the sparse data. We were unable to compare the diagnostic performance of the tests using formal statistical methods because of sparse data.

MAIN RESULTS

We included 54 studies involving a total of 3,196 participants evaluating the diagnostic accuracy of various index tests. In these 54 studies, eight different target conditions were identified with different final diagnoses constituting benign, precancerous, and cancerous lesions. None of the studies was of high methodological quality. None of the comparisons in which single studies were included was of sufficiently high methodological quality to warrant highlighting of the results. For differentiation of cancerous lesions from benign or precancerous lesions, we identified only one study per index test. The second analysis, of studies differentiating cancerous versus benign lesions, provided three tests in which meta-analysis could be performed. The sensitivities and specificities for diagnosing cancer were: EUS-FNA: sensitivity 0.79 (95% confidence interval (CI) 0.07 to 1.00), specificity 1.00 (95% CI 0.91 to 1.00); EUS: sensitivity 0.95 (95% CI 0.84 to 0.99), specificity 0.53 (95% CI 0.31 to 0.74); PET: sensitivity 0.92 (95% CI 0.80 to 0.97), specificity 0.65 (95% CI 0.39 to 0.84). The third analysis, of studies differentiating precancerous or cancerous lesions from benign lesions, only provided one test (EUS-FNA) in which meta-analysis was performed. EUS-FNA had moderate sensitivity for diagnosing precancerous or cancerous lesions (sensitivity 0.73 (95% CI 0.01 to 1.00) and high specificity 0.94 (95% CI 0.15 to 1.00), the extremely wide confidence intervals reflecting the heterogeneity between the studies). The fourth analysis, of studies differentiating cancerous (invasive carcinoma) from precancerous (dysplasia) provided three tests in which meta-analysis was performed. The sensitivities and specificities for diagnosing invasive carcinoma were: CT: sensitivity 0.72 (95% CI 0.50 to 0.87), specificity 0.92 (95% CI 0.81 to 0.97); EUS: sensitivity 0.78 (95% CI 0.44 to 0.94), specificity 0.91 (95% CI 0.61 to 0.98); EUS-FNA: sensitivity 0.66 (95% CI 0.03 to 0.99), specificity 0.92 (95% CI 0.73 to 0.98). The fifth analysis, of studies differentiating cancerous (high-grade dysplasia or invasive carcinoma) versus precancerous (low- or intermediate-grade dysplasia) provided six tests in which meta-analysis was performed. The sensitivities and specificities for diagnosing cancer (high-grade dysplasia or invasive carcinoma) were: CT: sensitivity 0.87 (95% CI 0.00 to 1.00), specificity 0.96 (95% CI 0.00 to 1.00); EUS: sensitivity 0.86 (95% CI 0.74 to 0.92), specificity 0.91 (95% CI 0.83 to 0.96); EUS-FNA: sensitivity 0.47 (95% CI 0.24 to 0.70), specificity 0.91 (95% CI 0.32 to 1.00); EUS-FNA carcinoembryonic antigen 200 ng/mL: sensitivity 0.58 (95% CI 0.28 to 0.83), specificity 0.51 (95% CI 0.19 to 0.81); MRI: sensitivity 0.69 (95% CI 0.44 to 0.86), specificity 0.93 (95% CI 0.43 to 1.00); PET: sensitivity 0.90 (95% CI 0.79 to 0.96), specificity 0.94 (95% CI 0.81 to 0.99). The sixth analysis, of studies differentiating cancerous (invasive carcinoma) from precancerous (low-grade dysplasia) provided no tests in which meta-analysis was performed. The seventh analysis, of studies differentiating precancerous or cancerous (intermediate- or high-grade dysplasia or invasive carcinoma) from precancerous (low-grade dysplasia) provided two tests in which meta-analysis was performed. The sensitivity and specificity for diagnosing cancer were: CT: sensitivity 0.83 (95% CI 0.68 to 0.92), specificity 0.83 (95% CI 0.64 to 0.93) and MRI: sensitivity 0.80 (95% CI 0.58 to 0.92), specificity 0.81 (95% CI 0.53 to 0.95), respectively. The eighth analysis, of studies differentiating precancerous or cancerous (intermediate- or high-grade dysplasia or invasive carcinoma) from precancerous (low-grade dysplasia) or benign lesions provided no test in which meta-analysis was performed.There were no major alterations in the subgroup analysis of cystic pancreatic focal lesions (42 studies; 2086 participants). None of the included studies evaluated EUS elastography or sequential testing.

AUTHORS' CONCLUSIONS

We were unable to arrive at any firm conclusions because of the differences in the way that study authors classified focal pancreatic lesions into cancerous, precancerous, and benign lesions; the inclusion of few studies with wide confidence intervals for each comparison; poor methodological quality in the studies; and heterogeneity in the estimates within comparisons.

Predicting the Grade of Dysplasia of Pancreatic Cystic Neoplasms Using Cyst Fluid DNA Methylation Markers

Purpose: Pancreatic cysts are common and pose diagnostic and management challenges. Pancreatic cyst fluid markers have the potential to aid in the management of cysts with concerning imaging findings. Our aim was to evaluate cyst fluid methylated DNA markers for their accuracy for predicting the histologic grade of neoplastic pancreatic cysts.Experimental Design: Pancreatic cyst fluid samples from 183 patients (29 discovery and 154 validation) aspirated after surgical resection were analyzed for methylated DNA at selected genes (SOX17, BNIP3, FOXE1, PTCHD2, SLIT2, EYA4, and SFRP1) using methylation-specific droplet-digital PCR (dd-QMSP). Methylated DNA levels were evaluated for their accuracy at predicting the grade of dysplasia of the pancreatic cyst.Results: All six markers evaluated in the validation set could accurately distinguish high-risk cystic neoplasms (with high-grade dysplasia and/or associated invasive cancer) from low-risk cysts (lower grades of dysplasia) with accuracies from 79.8% to 83.6%. Methylated SOX17 had the highest overall accuracy as a single marker (sensitivity, 78.4%; specificity, 85.6%; accuracy 83.6%, cutoff; 25 methylated DNA molecules/μL cyst fluid). The best four-gene combination had 84.3% sensitivity, 89.4% specificity, and 88.0% accuracy at distinguishing cysts with high-grade dysplasia and/or invasive cancer from those without. All six markers were independent predictors of having invasive cancer/high-grade dysplasia after adjusting for clinical/imaging factors known to be associated with grade of dysplasia. The combination of methylated SOX17 with cytology better predicted neoplastic grade than cytology alone.Conclusions: A panel of methylated gene markers quantified by dd-QMSP can be used to predict the grade of dysplasia of pancreatic cysts. Clin Cancer Res; 23(14); 3935-44. ©2017 AACR.

Cyst Fluid Telomerase Activity Predicts the Histologic Grade of Cystic Neoplasms of the Pancreas

PURPOSE

Pancreatic cysts frequently pose clinical dilemmas. On one hand, cysts with high-grade dysplasia offer opportunities for cure, on the other hand, those with low-grade dysplasia are easily over treated. Cyst fluid markers have the potential to improve the evaluation of these cysts. Because telomerase activity is commonly activated in malignant cells, we evaluated the diagnostic performance of cyst fluid telomerase activity measurements for predicting histologic grade.

EXPERIMENTAL DESIGN

Telomerase activity was measured using telomerase repeat amplification with digital-droplet PCR in surgically aspirated cyst fluid samples from 219 patients who underwent pancreatic resection for a cystic lesion (184 discovery, 35 validation) and 36 patients who underwent endoscopic ultrasound fine-needle aspiration. Methodologic and clinical factors associated with telomerase activity were examined.

RESULTS

Telomerase activity was reduced in samples that had undergone prior thawing. Among 119 samples not previously thawed, surgical cyst fluids from cystic neoplasms with high-grade dysplasia ± associated invasive cancer had higher telomerase activity [median (interquartile range), 1,158 (295.9-13,033)] copies/μL of cyst fluid than those without [19.74 (2.58-233.6) copies/μL; P < 0.001)]. Elevated cyst fluid telomerase activity had a diagnostic accuracy for invasive cancer/high-grade dysplasia of 88.1% (discovery), 88.6% (validation), and 88.2% (merged). Among cysts classified preoperatively as having "worrisome features," cyst fluid telomerase activity had high diagnostic performance (sensitivity 73.7%, specificity 90.6%, accuracy, 86.1%). In multivariate analysis, telomerase activity independently predicted the presence of invasive cancer/high-grade dysplasia.

CONCLUSIONS

Cyst fluid telomerase activity can be a useful predictor of the neoplastic grade of pancreatic cysts. Clin Cancer Res; 22(20); 5141-51. ©2016 AACRSee related commentary by Allen et al., p. 4966.

"Wet suction technique (WEST)": a novel way to enhance the quality of EUS-FNA aspirate. Results of a prospective, single-blind, randomized, controlled trial using a 22-gauge needle for EUS-FNA of solid lesions

BACKGROUND

Contemporary EUS-guided FNA techniques involve the use of a needle, with an air column within the lumen, with or without suction. We describe a novel technique with an aim to improve the quality of the aspirate.

OBJECTIVE

To compare a novel "wet suction" technique (WEST) with the conventional FNA technique (CFNAT) of EUS-guided FNA using a 22-gauge FNA needle.

DESIGN

Prospective, single-blind, and randomized trial.

SETTING

Two large tertiary-care hospitals.

PATIENTS

All consecutive adult patients presenting for EUS with possible FNA of solid lesions were offered the chance to participate in the study.

METHODS

All lesions were sampled with the same needle by using alternating techniques. Patients were randomized to the WEST versus the CFNAT for the first pass. If the first pass was made with the WEST, the second pass was made with the CFNAT, and subsequent passes were made in an alternating manner by using the same sequence. All FNAs were performed using 22-gauge needles.

MAIN OUTCOME MEASUREMENTS

Specimen adequacy, cellularity, and blood contamination of EUS-guided FNA aspirates graded on a predefined scale.

RESULTS

The WEST yielded significantly higher cellularity in a cell block compared with the CFNAT, with a mean cellularity score of 1.82±0.76 versus 1.45±0.768 (P<.0003). The WEST cell block resulted in a significantly better specimen adequacy of 85.5% versus 75.2% (P<.035). There was no difference in the amount of blood contamination between the 2 techniques.

LIMITATIONS

Lack of cross check and grading by a second cytopathologist.

CONCLUSION

The novel WEST resulted in significantly better cellularity and specimen adequacy in cell blocks of EUS-guided FNA aspirate of solid lesions than the CFNAT.

Eliminating the Residual Negative Pressure in the Endoscopic Ultrasound Aspirating Needle Enhances Cytology Yield of Pancreas Masses

BACKGROUND

Prior to withdrawing the EUS-FNA needle from the lesion, the stopcock of the suction syringe is closed to reduce contamination. Residual negative pressure (RNP) may persist in the needle despite closing the stopcock.

AIMS

To determine whether neutralizing RNP before withdrawing the needle will improve the cytology yield.

METHODS

Bench-top testing was done to confirm the presence of RNP followed by a prospective, randomized, cross-over study on patients with pancreas mass. Ten milliliters of suction was applied to the FNA needle. Before withdrawing the needle from the lesion, the stopcock was closed. Based on randomization, the first pass was done with the stopcock either attached to the needle (S+) or disconnected (S-) to allow air to enter and neutralize RNP and accordingly the second pass was crossed over to S+ or S-. On-site cytopathologist was blinded to S+/S-.

RESULTS

Bench tests confirmed the presence of RNP which was successfully neutralized by disconnecting the syringe (S-) from the needle. Sixty patients were enrolled, 120 samples analyzed. S+ samples showed significantly greater GI tract contamination compared to S- samples (16.7 vs. 6.7%, p = 0.03). Of the 53 patients confirmed to have pancreas adenocarcinoma, FNA using S- approach was positive in 49 (93%) compared to 40 using the S+ approach (76%, p = 0.02).

CONCLUSIONS

Despite closing the stopcock of the suction syringe, RNP is present in the FNA needle. Neutralizing RNP prior to withdrawing the needle from the target lesion significantly decreased GI tract contamination of the sample thereby improving the FNA cytology yield.

CLINICAL TRIALS REGISTRATION NUMBER

NCT01995474.

Endoscopic ultrasound-guided fine-needle aspiration for the diagnosis of pancreatic cysts by combined cytopathology and cystic content analysis

Recent advances in imaging technology have resulted in an increase in incidental discoveries of pancreatic cystic lesions. Pancreatic cysts comprise a wide variety of lesions and include non-neoplastic cysts and neoplastic cysts. Because some pancreatic cysts have more of a malignant potential than others, it is absolutely essential that an accurate diagnosis is rendered so that effective care can be given to each patient. In many centers, endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) has emerged as the modality of choice that enables one to distinguish between mucinous and non-mucinous lesion, diagnose malignancy and collect cyst fluid for further diagnostic studies, such as pancreatic enzyme levels, molecular analysis and other tumor biomarkers. The current review will focus on EUS-guided FNA and the cytological diagnosis for pancreatic cysts.

Ultrasound-guided percutaneous fine-needle aspiration of solid pancreatic neoplasms: 10-year experience with more than 2,000 cases and a review of the literature

OBJECTIVES

To evaluate the diagnostic accuracy and complication rate of percutaneous ultrasound-guided fine-needle aspiration (US-FNA) of solid pancreatic neoplasms through the analysis of 10-year experiences of two centres.

METHODS

Clinical, radiological and pathologic data of 2,024 patients with solid pancreatic masses who underwent US-FNAs were retrospectively evaluated. Indications for aspiration were: unresectable lesions before neo-adjuvant therapy; doubtful imaging findings; and suspicion of uncommon neoplasms with prognostic or therapeutic implications such as metastases or lymphoma. US-FNAs were performed using aspiration needles with a cytopathologist present in centre 1. In centre 2, cytologic samples were collected with Chiba needles and separately evaluated by a cytopathologist.

RESULTS

US-FNA had a diagnostic sample rate of 92.2 % (centre 1: 95.9 %; centre 2: 87.2 %). US-FNA repetition after non-diagnostic samples provided a diagnosis in 86.3 % of cases. Sensitivity, specificity, positive and negative predictive values, and accuracy were 98.7 %, 100 %, 100 %, 75.5 %, and 98.7 %, respectively. The complication rate was 0.8 %.

CONCLUSIONS

Percutaneous US-FNA is a sensitive, accurate and safe method for the invasive diagnosis of solid pancreatic neoplasms. The use of aspiration needles and the on-site presence of a cytopathologist may lead to a high rate of diagnostic samples, thus reducing the need for US-FNA repetition.

KEY POINTS

• Percutaneous ultrasound-guided fine-needle aspiration of pancreatic neoplasms is sensitive and accurate. • The short-term complication rate of percutaneous ultrasound-guided fine-needle aspiration is low. • Technical aspects may influence the rate of diagnostic samples.

Accuracy of 18F-FDG PET/CT, Multidetector CT, and MR Imaging in the Diagnosis of Pancreatic Cysts: A Prospective Single-Center Study

Accurate diagnosis of the nature of pancreatic cysts is challenging but more important than ever, in part because of the increasing number of incidental cystic findings in the pancreas. Preliminary data suggest that (18)F-FDG PET/CT may have a significant influence on clinical decision making, although its role is still evolving. Our aim was to prospectively compare the accuracy of combined (18)F-FDG PET and contrast-enhanced CT ((18)F-FDG PET/CT), multidetector CT (MDCT), and MR imaging in differentiating malignant from benign pancreatic cysts.

METHODS

Thirty-one consecutive patients with pancreatic cysts were enrolled in the study. They underwent a protocol including (18)F-FDG PET/CT, MDCT, and MR imaging combined with MR cholangiopancreatography, all of which were evaluated in a masked manner. The findings were confirmed macroscopically at surgery or histopathologic analysis (n = 22) or at follow-up (n = 9).

RESULTS

Of the 31 patients, 6 had malignant and 25 had benign lesions. The diagnostic accuracy was 94% for (18)F-FDG PET/CT, compared with 77% and 87% for MDCT (P < 0.05) and MR imaging, respectively. (18)F-FDG PET/CT had a negative predictive value of 100% and a positive predictive value of 75% for pancreatic cysts. The maximum standardized uptake value was significantly higher in malignant (7.4 ± 2.6) than in benign lesions (2.4 ± 0.8) (P < 0.05). When the maximum standardized uptake value was set at 3.6, the sensitivity and specificity were 100% and 88%, respectively. Furthermore, when compared with MDCT and MR imaging, respectively, (18)F-FDG PET/CT altered the clinical management of 5 and 3 patients, respectively.

CONCLUSION

(18)F-FDG PET/CT is an accurate imaging modality for differentiating between benign and malignant pancreatic cysts. We recommend the use of (18)F-FDG PET/CT in the evaluation of diagnostically challenging pancreatic cysts.

Endoscopic ultrasound-guided pancreatic fine-needle aspiration: potential pitfalls in one institution's experience of 1212 procedures

BACKGROUND

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has emerged as the diagnostic modality of choice for mass lesions in the pancreas. The objective of the current study was to determine the accuracy and pitfalls of EUS-FNA in the diagnosis of pancreatic lesions in cases that involved follow-up surgical resection.

METHODS

Cases of EUS-FNA of pancreatic lesions performed from 2007 to mid-2012 for which subsequent surgical resection was performed were retrieved from the department's database. The accuracy of the cytologic diagnosis was assessed using the histological diagnosis as the gold standard. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated. "Neoplastic," "suspicious," and "malignant" were classified as a positive cytologic diagnosis. In one calculation method, "atypical" was also included as a positive cytologic diagnosis whereas in another it was not considered to be a positive cytological result. The cases with a cytologic-histological discrepancy were reviewed to identify sources of errors.

RESULTS

A total of 1212 cases from 1104 patients (518 women and 586 men; age range, 18-94 years [average age, 63.5 years]) were identified. Cytologic diagnoses included 52 unsatisfactory, 224 benign, 129 atypical, 140 neoplasm, 35 suspicious, and 632 malignant diagnoses. Of these cases, 397 patients had histological follow-up information available. The sensitivity, specificity, positive predictive value, and negative predictive value were 83.2%, 85.9%, 95.9%, and 56.1%, respectively, with atypical cases excluded from the analysis. When atypical cases were included as a positive cytologic diagnosis, the sensitivity, specificity, positive predictive value, and negative predictive value were 86.7%, 67.9%, 90.7%, and 58.5%, respectively, and were 73.7%, 87.7%, 95.6%, and 48.0%, respectively, when atypical cases were included as a negative cytologic diagnosis. The major difficulty in EUS-FNA cytology was to differentiate pancreatic mucinous neoplasms from contaminants of gastric mucosa. Other pitfalls included differentiating mucinous neoplasm from extensive pancreatic intraepithelial neoplasia, and endocrine tumor from nesidioblastosis versus acinar cell carcinoma or intrapancreatic spleen.

CONCLUSIONS

EUS-FNA is a valuable tool for the diagnosis of pancreatic lesions, especially solid malignant tumors. Cytologic-radiological correlation is essential in differentiating pancreatic mucinous neoplasms from gastric mucosa, because the former usually are found to have characteristic features on imaging. Pathologists should be aware of the pitfalls in the cytologic diagnosis of pancreatic lesions that may significantly change the clinical management of the patients.

Diagnostic efficacy of cell block immunohistochemistry, smear cytology, and liquid-based cytology in endoscopic ultrasound-guided fine-needle aspiration of pancreatic lesions: a single-institution experience

Background

The diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) cytology varies widely depending on the treatment method of the specimens. The present study aimed to evaluate the diagnostic efficacy of cell block (CB) immunohistochemistry, smear cytology (SC), and liquid-based cytology (LBC) in patients with pancreatic lesions without consulting an on-site cytopathologist.

Methods

This study prospectively enrolled 72 patients with pancreatic lesions. The EUS-FNA specimens were examined by SC, LBC, and CB immunohistochemistry. The diagnostic efficacy of the 3 methods was then compared. Patients’ final diagnosis was confirmed by surgical resection specimens, diagnostic imaging, and clinical follow-up.

Results

Our results included 60 malignant and 12 benign pancreatic lesions. The diagnostic sensitivity (90%), negative predictive value (66.7%), and accuracy (91.7%) of CB immunohistochemistry were significantly higher than those of SC (70.0%, 30.0%, and 75.0%, respectively) and LBC (73.3%, 31.6%, and 77.8%, respectively) (all P<0.05). The combination of CB and SC, or CB and LBC, did not significantly increase the efficacy compared to CB immunohistochemistry alone.

Conclusion

Our findings suggest that in the absence of an on-site cytopathologist, CB immunohistochemistry on EUS-FNA specimens offers a higher diagnostic efficacy in patients with pancreatic lesions than does SC and LBC.

The added value of using mutational profiling in addition to cytology in diagnosing aggressive pancreaticobiliary disease: review of clinical cases at a single center

Background

This study aimed to better understand the supporting role that mutational profiling (MP) of DNA from microdissected cytology slides and supernatant specimens may play in the diagnosis of malignancy in fine-needle aspirates (FNA) and biliary brushing specimens from patients with pancreaticobiliary masses.

Methods

Cytology results were examined in a total of 30 patients with associated surgical (10) or clinical (20) outcomes. MP of DNA from microdissected cytology slides and from discarded supernatant fluid was analyzed in 26 patients with atypical, negative or indeterminate cytology.

Results

Cytology correctly diagnosed aggressive disease in 4 patients. Cytological diagnoses for the remaining 26 were as follows: 16 negative (9 false negative), 9 atypical, 1 indeterminate. MP correctly determined aggressive disease in 1 false negative cytology case and confirmed a negative cytology diagnosis in 7 of 7 cases of non-aggressive disease. Of the 9 atypical cytology cases, MP correctly diagnosed 7 as positive and 1 as negative for aggressive disease. One specimen that was indeterminate by cytology was correctly diagnosed as non-aggressive by MP. When first line malignant (positive) cytology results were combined with positive second line MP results, 12/21 cases of aggressive disease were identified, compared to 4/21 cases identified by positive cytology alone.

Conclusions

When first line cytology results were uncertain (atypical), questionable (negative), or not possible (non-diagnostic/indeterminate), MP provided additional information regarding the presence of aggressive disease. When used in conjunction with first line cytology, MP increased detection of aggressive disease without compromising specificity in patients that were difficult to diagnose by cytology alone.

Pitfalls in EUS FNA

Although endoscopic ultrasound (EUS) fine-needle aspiration (FNA) is a safe and accurate procedure, the diagnostic yield varies. Factors contributing to the diagnostic accuracy of EUS FNA include endosonographer and cytopathologist experience, EUS image recognition, accurate FNA targeting of the lesion, proper specimen collection and handling, use of ancillary techniques, and accurate cytologic interpretation. Errors in performance or judgment made before, during, or after the procedure may affect the results of the EUS FNA. The authors discuss the potential pitfalls of EUS FNA and methods to avoid their occurrence to optimize the diagnostic yield, efficiency, and safety of the procedure.