Tips for endoscopic ultrasound-guided fine needle aspiration of various pancreatic lesions

Selection methods for endoscopic ultrasound‑guided biliary drainage cases that are appropriate for beginners

Endoscopic ultrasound-guided biliary drainage (EUS-BD) is performed as a second drainage method when endoscopic retrograde cholangiopancreatography-guided biliary drainage fails. There are several severe adverse events in EUS-BD, and avoiding technical failure is desirable. Although EUS-BD is a skilled endoscopic treatment, the appropriate conditions for EUS-BD beginners are not well known. The present study aimed to clarify the appropriate cases for EUS-BD beginners. The present retrospective cohort study included patients with malignant biliary obstruction who underwent EUS-BD, which was performed by beginners between March 2005 and June 2024. Factors associated with successful EUS-BD performed by beginners were evaluated by multivariate logistic regression analysis. The performance of each factor was evaluated via a receiver operating characteristic (ROC) curve. According to multivariate analysis, the diameter of the punctured bile duct was associated with successful EUS-BD performed by beginners (odds ratio, 1.34; 95% CI, 1.03-1.75; P=0.031). The area under the ROC curve for the diameter of the punctured bile duct was 0.79, and the cutoff value was 6.7 mm (71% sensitivity and 81.8% specificity). The diameter of the punctured bile duct might be associated with successful EUS-BD procedures performed by beginners. When a beginner performs EUS-BD, a diameter of the targeted bile duct >6.7 mm might be desirable for successful procedures.

Fully automated magnetic resonance imaging-based radiomics analysis for differentiating pancreatic adenosquamous carcinoma from pancreatic ductal adenocarcinoma

PURPOSE

To develop and validate an automated magnetic resonance imaging (MRI)-based model to preoperatively differentiate pancreatic adenosquamous carcinoma (PASC) from pancreatic ductal adenocarcinoma (PDAC).

METHODS

This retrospective study included patients with surgically resected, histopathologically confirmed PASC or PDAC who underwent MRI between January 2011 and December 2020. According to time of treatment, they were divided into training and validation sets. Automated deep-learning-based artificial intelligence was used for pancreatic tumor segmentation. Linear discriminant analysis was performed with conventional MRI and radiomic features to develop clinical, radiomics, and mixed models in the training set. The models' performances were determined from their discrimination and clinical utility. Kaplan-Meier and log-rank tests were used for survival analysis.

RESULTS

Overall, 389 and 123 patients with PDAC (age, 61.37 ± 9.47 years; 251 men) and PASC (age, 61.99 ± 9.82 years; 78 men) were included, respectively; they were split into the training (n = 358) and validation (n = 154) sets. The mixed model showed good performance in the training and validation sets (area under the curve: 0.94 and 0.96, respectively). The sensitivity, specificity, and accuracy were 76.74%, 93.38%, and 89.39% for the training set, respectively, and 67.57%, 97.44%, and 90.26% for the validation set, respectively. The mixed model outperformed the clinical (p = 0.001) and radiomics (p = 0.04) models in the validation set. Log-rank test revealed significantly longer survival in the predicted PDAC group than in the predicted PASC group (p = 0.003), according to the mixed model.

CONCLUSION

Our mixed model, which combined MRI and radiomic features, can be used to differentiate PASC from PDAC.

Radiomics nomogram for the preoperative prediction of lymph node metastasis in pancreatic ductal adenocarcinoma

PURPOSE

To develop and validate a radiomics nomogram for the preoperative prediction of lymph node (LN) metastasis in pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

In this retrospective study, 225 patients with surgically resected, pathologically confirmed PDAC underwent multislice computed tomography (MSCT) between January 2014 and January 2017. Radiomics features were extracted from arterial CT scans. The least absolute shrinkage and selection operator method was used to select the features. Multivariable logistic regression analysis was used to develop the predictive model, and a radiomics nomogram was built and internally validated in 45 consecutive patients with PDAC between February 2017 and December 2017. The performance of the nomogram was assessed in the training and validation cohort. Finally, the clinical usefulness of the nomogram was estimated using decision curve analysis (DCA).

RESULTS

The radiomics signature, which consisted of 13 selected features of the arterial phase, was significantly associated with LN status (p < 0.05) in both the training and validation cohorts. The multivariable logistic regression model included the radiomics signature and CT-reported LN status. The individualized prediction nomogram showed good discrimination in the training cohort [area under the curve (AUC), 0.75; 95% confidence interval (CI), 0.68-0.82] and in the validation cohort (AUC, 0.81; 95% CI, 0.69-0.94) and good calibration. DCA demonstrated that the radiomics nomogram was clinically useful.

CONCLUSIONS

The presented radiomics nomogram that incorporates the radiomics signature and CT-reported LN status is a noninvasive, preoperative prediction tool with favorable predictive accuracy for LN metastasis in patients with PDAC.

Comparison of Histological Sample Volumes among Various Endoscopic Ultrasound-Guided Biopsy Needles

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) enables easy and accurate pathological assessment. Here, we compared and assessed the area of samples on glass slides for three needle types: a 19-gauge Franseen needle (Acquire, Boston Scientific, Natick, MA, USA), a 22-gauge Franseen needle, and a 19-gauge fine-needle aspiration (FNA) needle (EZ Shot 3 Plus; Olympus, Tokyo, Japan). Among patients with suspected pancreatic cancer, with a ≥20 mm tumor located in the pancreatic body and tail, and who underwent EUS-FNA or FNB between June 2018 and March 2020, 10 were randomly selected to test each needle. The areas of histological tissue and blood clot samples were measured using the BZ-X800 imaging software (Keyence Corporation, Osaka, Japan). Baseline patient characteristics and pathological sample data showed no significant differences among the needles. The 19-gauge Franseen needle obtained significantly more histological tissue samples than the 19-gauge conventional needle (p = 0.010) and 22-gauge Franseen needle (p = 0.008). Conversely, there was no significant difference between the 19-gauge conventional needle and 22-gauge Franseen needle (p = 0.838) in this regard. The 19-gauge Franseen needle could collect more samples than the other needles, contributing to giving a more precise pathological diagnosis and more information, including genomic profiling.

Diagnostic Fine-Needle Biopsy of Small Solid Pancreatic Lesions Using a Franseen Needle during Endoscopic Ultrasound Examination

BACKGROUND AND AIM

During endoscopic ultrasound-guided fine needle aspiration biopsy (EUS-FNB), Franseen needles can help collect sufficient tissue to permit histopathological assessment. However, its efficacy might be limited by the size of the targeted lesion. This study aimed to evaluate the feasibility of histopathological assessment of small solid pancreatic lesions using a 22-gauge Franseen needle during EUS-FNB.

METHODS

This retrospective study evaluated data from all patients who underwent EUS-FNB using a Franseen needle for solid pancreatic lesions at the University of Toyama Hospital between June 2018 and April 2020.

RESULTS

The study included 159 patients who had 152 malignant lesions and 7 benign lesions. The malignant lesions included pancreatic cancers (n = 134), neuroendocrine neoplasms (n = 15), metastatic tumors (n = 2), and a solid pseudopapillary neoplasm (n = 1). The diagnostic accuracy of EUS-FNB (combining histology and cytology) was 98.7%. However, the histopathological diagnosis was only confirmed for 64.3% of small lesions (<10 mm), relative to 97.2% for larger lesions. Multivariate analysis also revealed that lesion size of <10 mm predicted a less accurate histopathological diagnosis (odds ratio: 6.97, 95% confidence interval: 1.02-47.67; p = 0.041). Further analyses revealed a failed histological diagnosis in 4 patients with lesions of <5 mm in size and accurate diagnoses in 9 out of 10 patients with lesions of 5-10 mm in size.

CONCLUSIONS

The diagnostic accuracy for small lesions (<10 mm), especially for lesions of <5 mm, based on histological examination alone, was significantly lower than that for others (>10 mm). Furthermore, multivariate analysis revealed that only lesion size was an independent predictor of histopathological diagnosis accuracy.

Relationship Between Radiomics and Risk of Lymph Node Metastasis in Pancreatic Ductal Adenocarcinoma

OBJECTIVE

The objective of this study was to explore the exact relationship between the arterial radiomics score (rad-score) and lymph node (LN) metastasis in pancreatic ductal adenocarcinoma (PDAC).

METHODS

A total of 225 patients with pathologically confirmed PDAC who underwent multislice computed tomography within 1 month of resection from December 2016 to August 2017 were retrospectively studied. For each patient, 1029 radiomics features of arterial phase were extracted, which were reduced using the least absolute shrinkage and selection operator logistic regression algorithm. Multivariate logistic regression models were used to analyze the association between the arterial rad-score and LN metastasis.

RESULTS

Lymph node-negative and LN-positive patients accounted for 107 (47.56%) and 118 (52.44%) of the cohort, respectively. The rad-score, which consisted of 12 selected features of the arterial phase, was significantly associated with LN status (P < 0.05). Univariate analysis revealed that the arterial rad-score and T stage were independently and positively associated with risk of LN metastasis (P < 0.05). Multivariate analyses revealed a significant association between the arterial rad-score and the LN metastasis (P < 0.0001). Higher arterial rad-score was associated with LN metastasis (P for trend <0.0001).

CONCLUSIONS

The arterial rad-score is independently and positively associated with the risk of LN metastasis in PDAC.

Efficacy of 3 fine-needle biopsy techniques for suspected pancreatic malignancies in the absence of an on-site cytopathologist

BACKGROUND AND AIMS

EUS-guided fine-needle aspiration/biopsy (EUS-FNA/B) has a high diagnostic accuracy for pancreatic tumors. Most reports have focused on the diagnostic yield of cytology or histology; the ability of various FNA/B techniques to obtain an adequate mass of cells or tissue has rarely been investigated.

METHODS

Patients with suspected pancreatic malignancy underwent EUS-FNB using a 22-gauge ProCore needle by either the stylet slow-pull-back technique (group A), conventional negative suction after stylet removal (group B), or non-suction after stylet removal (group C) in the absence of an on-site cytopathologist. The adequacy of the 3 techniques based on the diagnostic yield, cellularity, blood contamination, and core-tissue acquisition was evaluated.

RESULTS

A total of 50 patients (27 males) were analyzed. The mean tumor size was 21 to 40 mm in 54%. The rate of a good or excellent proportion of cellularity was highest in group A compared with groups B and C (72% vs 60% vs 50%, P = .049). A >25% rate of blood contamination was more prevalent in group B (30% vs 42% vs 10%, P = .009). The rate of adequate core-tissue acquisition was not different (52% vs 34% vs 50%, P = .140). Based on the multivariate generalized estimation equation, the stylet slow-pull-back technique and a tumor size >40 mm were favorable factors for diagnostic adequacy.

CONCLUSIONS

The stylet slow-pull-back technique might enable acquisition of tissue and assessment of cellularity for the diagnosis of pancreatic tumors suspected to be malignant. (Clinical trial registration number: KCT0002190.).

Slow-Pull Using a Fanning Technique Is More Useful Than the Standard Suction Technique in EUS-Guided Fine Needle Aspiration in Pancreatic Masses

Background/Aims

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is useful for obtaining pancreatic mass samples. The combination of modified techniques (i.e., slow-pull technique and fanning technique) may improve the quality of the sample obtained by EUS-FNA. We investigated the effectiveness of a combined slow-pull fanning technique in EUS-FNA for pancreatic mass.

Methods

This prospective comparative study investigated EUS-FNA performed for pancreatic solid masses between August 2015 and July 2016. Pairwise specimens were alternately obtained using the following two techniques for targeted pancreatic lesions: standard suction or slow-pull with fanning. We compared the specimen quality, blood contamination, and diagnostic accuracy of these techniques.

Results

Forty-eight consecutive patients were included (29 men; mean age, 68.1±11.9 years), and 96 pancreatic mass specimens were obtained. The slow-pull with fanning technique had a significantly superior diagnostic accuracy than the suction technique (88% vs 71%, p=0.044). Furthermore, blood contamination was significantly reduced using the slow-pull with fanning technique (ratio of no or slight contamination, 77% vs 56%, p=0.041). No difference was observed in the acquisition of adequate cellularity between the groups. In the subgroup analysis, the tumor size and sampling technique were related to the EUS-FNA diagnostic accuracy.

Conclusions

The slow-pull with needle fanning technique showed a good diagnostic yield for EUS-FNA for pancreatic mass. This technique can be useful for performing EUS-guided sampling for diagnosing pancreatic disease.

Push vs pull method for endoscopic ultrasound-guided fine needle aspiration of pancreatic head lesions: Propensity score matching analysis

AIM

To evaluate the efficacy of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) of pancreatic head cancer when pushing (push method) or pulling the echoendoscope (pull method).

METHODS

Overall, 566 pancreatic cancer patients had their first EUS-FNA between February 2001 and December 2017. Among them, 201 who underwent EUS-FNA for pancreatic head lesions were included in this study. EUS-FNA was performed by the push method in 85 patients, the pull method in 101 patients and both the push and pull methods in 15 patients. After propensity score matching (age, sex, tumor diameter, and FNA needle), 85 patients each were stratified into the push and pull groups. Patient characteristics and EUS-FNA-related factors were compared between the two groups.

RESULTS

Patient characteristics were not significantly different between the two groups. The distance to lesion was significantly longer in the push group than in the pull group (13.9 ± 4.9 mm vs 7.0 ± 4.9 mm, P < 0.01). The push method was a significant factor influencing the distance to lesion (≥ median 10 mm) (P < 0.01). Additionally, tumor diameter ≥ 25 mm (OR = 1.91, 95%CI: 1.02-3.58, P = 0.043) and the push method (OR = 1.91, 95%CI: 1.03-3.55, P = 0.04) were significant factors contributing to the histological diagnosis of malignancy.

CONCLUSION

The pull method shortened the distance between the endoscope and the lesion and facilitated EUS-FNA of pancreatic head cancer. The push method contributed to the histological diagnosis of pancreatic head cancer using EUS-FNA specimens.

Endoscopic Ultrasound Imaging for Differential Diagnosis of Pancreatic Neoplasms: A 7-Year Study in a Chinese Population

Background

Currently, non-invasive methods for screening pancreatic cancer are lacking. There is little information regarding whether endoscopic ultrasound (EUS) imaging has a discriminatory ability for detecting benign and malignant pancreatic neoplasms. In this study, we retrospectively analyzed the demographic, clinicopathologic, and EUS features and follow-up information.

Material/Methods

A total of 58 patients with pancreatic neoplasms who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) over a 7-year period (2009–2016) at our Department of Digestive Diseases were enrolled in our study.

Results

Of the 58 patients, 38 (65.5%) were diagnosed with malignant pancreatic neoplasms and 20 (34.5%) were benign ones. Of all the EUS findings, size of neoplasm (P=0.037) and regularity of margin (P=0.011) were significantly different between malignant and benign pancreatic neoplasms. However, age, sex, location, echo pattern, and dilation of main pancreatic duct did not show any significant difference (P>0.05). Size combined with regularity to detect malignant pancreatic neoplasms showed the following diagnostic values: sensitivity, 73.68%; specificity, 90%; positive predictive value, 76.60%; negative predictive value 81.82%; and area under the receiver operating characteristic curve, 0.887 (95% CI: 0.777–0.955, P<0.0001).

Conclusions

Our results showed the high value of EUS for differentiating malignant pancreatic neoplasms from benign ones. Due to this and its non-invasive nature, EUS should be the first-line method for detection of neoplastic pancreatic lesions.

Novel quantitative analysis of the S100P protein combined with endoscopic ultrasound-guided fine needle aspiration cytology in the diagnosis of pancreatic adenocarcinoma

Specimens obtained with endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) are often tiny and fragmented leading to an inconclusive and doubtful diagnosis. To overcome the limitations of EUS-FNA in the cytological diagnosis of pancreatic adenocarcinoma (PCA), we evaluated whether quantification of the S100P protein combined with EUS-FNA reliably discriminated between PCA and benign pancreatic lesions (BPL). A high sensitivity sandwich ELISA for S100P protein was developed to aid in the detection of PCA in small samples obtained using EUS-FNA. After experimental verification of the sandwich ELISA with cell lines and mouse xenograft tumors, 27 consecutive patients with suspicious PCA who underwent EUS-FNA were enrolled in the present study examining the combination of S100P protein assessment and EUS-FNA cytology. The concentration of the S100P protein in EUS-FNA samples from the PCA group was significantly higher than that in the BPL group (P=0.04). Using receiver operating characteristic curve analysis, we determined the S100P protein cut-off value for PCA diagnosis to be 99.8 ng/ml. The S100P protein levels combined with EUS-FNA cytology to detect PCA showed the following diagnostic values: sensitivity, 94.4% [95% confidence interval (CI), 75.7-99.1%]; specificity, 88.9% (95% CI, 51.8-99.7%); positive predictive value, 94.4% (95% CI, 72.7-99.9%); negative predictive value, 88.9% (95% CI, 51.8-99.7%); accuracy, 92.6% (95% CI, 75.7‑99.1%); and area under the curve, 0.92 (95% CI, 0.79-1.00). We established a novel quantitative analysis for the S100P protein in EUS-FNA samples which, when combined with EUS-FNA cytology, could provide promising results for the reliable diagnosis of PCA.

Endoscopic ultrasonography guided-fine needle aspiration for the diagnosis of solid pancreaticobiliary lesions: Clinical aspects to improve the diagnosis

Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) has been applied to pancreaticobiliary lesions since the 1990s and is in widespread use throughout the world today. We used this method to confirm the pathological evidence of the pancreaticobiliary lesions and to perform suitable therapies. Complications of EUS-FNA are quite rare, but some of them are severe. Operators should master conventional EUS observation and experience a minimum of 20-30 cases of supervised EUS-FNA on non-pancreatic and pancreatic lesions before attempting solo EUS-FNA. Studies conducted on pancreaticobiliary EUS-FNA have focused on selection of suitable instruments (e.g., needle selection) and sampling techniques (e.g., fanning method, suction level, with or without a stylet, optimum number of passes). Today, the diagnostic ability of EUS-FNA is still improving; the detection of pancreatic cancer (PC) currently has a sensitivity of 90%-95% and specificity of 95%-100%. In addition to PC, a variety of rare pancreatic tumors can be discriminated by conducting immunohistochemistry on the FNA materials. A flexible, large caliber needle has been used to obtain a large piece of tissue, which can provide sufficient histological information to be helpful in classifying benign pancreatic lesions. EUS-FNA can supply high diagnostic yields even for biliary lesions or peri-pancreaticobiliary lymph nodes. This review focuses on the clinical aspects of EUS-FNA in the pancreaticobiliary field, with the aim of providing information that can enable more accurate and efficient diagnosis.

Diagnostic ability of EUS-FNA for pancreatic solid lesions with conventional 22-gauge needle using the slow pull technique: a prospective study

OBJECTIVE

Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) using the slow pull technique (SP-FNA) has recently attracted attention as an effective tissue acquisition technique. However, efficacy of SP-FNA with a 22-gauge conventional needle remains unclear. The aim of this study is to evaluate the diagnostic ability of SP-FNA with a 22-gauge needle.

MATERIAL AND METHODS

Patients with a pancreatic solid lesion were prospectively enrolled in this study. SP-FNA was performed at two needle passes with a 22-gauge needle. One dedicated pathologist evaluated the obtained samples in terms of quantity (Grade 0: scant; Grade 1: inadequate; Grade 2: adequate), quality (Grade 0: poor; Grade 1: moderate; Grade 2: good), and blood contamination (Grade 0: significant; Grade 1: moderate; Grade 2: low), and provided a pathological diagnosis. Additional EUS-FNA was performed by applying suction (SA-FNA). The evaluation points were as follows: diagnostic accuracy of SP-FNA compared with that of SA-FNA, and the quantity, quality, and blood contamination level of SP-FNA-obtained samples.

RESULTS

We enrolled 40 cases. The diagnostic accuracy of SP-FNA was 90% (36/40). There was no significant difference in the accuracy between SP-FNA and SA-FNA (90% vs. 90%, p = 1.000). The samples obtained using SP-FNA were assessed as Grade 2 for quantity in 29 cases (73%), quality in 31 (78%), and blood contamination in 25 (63%).

CONCLUSIONS

Adequate, high-quality, and unsubstantially blood-contaminated samples could be obtained using SP-FNA. The diagnostic ability of SP-FNA was 90%, which appeared to be similar to that of SA-FNA.

Endoscopic ultrasonography for surveillance of individuals at high risk for pancreatic cancer

Pancreatic cancer is a highly lethal disease with a genetic susceptibility and familial aggregation found in 3%-16% of patients. Early diagnosis remains the only hope for curative treatment and improvement of prognosis. This can be reached by the implementation of an intensive screening program, actually recommended for individuals at high-risk for pancreatic cancer development. The aim of this strategy is to identify pre-malignant precursors or asymptomatic pancreatic cancer lesions, curable by surgery. Endoscopic ultrasound (EUS) with or without fine needle aspiration (FNA) seems to be the most promising technique for early detection of pancreatic cancer. It has been described as a highly sensitive and accurate tool, especially for small and cystic lesions. Pancreatic intraepithelial neoplasia, a precursor lesion which is highly represented in high-risk individuals, seems to have characteristics chronic pancreatitis-like changes well detected by EUS. Many screening protocols have demonstrated high diagnostic yields for pancreatic pre-malignant lesions, allowing prophylactic pancreatectomies. However, it shows a high interobserver variety even among experienced endosonographers and a low sensitivity in case of chronic pancreatitis. Some new techniques such as contrast-enhanced harmonic EUS, computer-aided diagnostic techniques, confocal laser endomicroscopy miniprobe and the detection of DNA abnormalities or protein markers by FNA, promise improvement of the diagnostic yield of EUS. As the resolution of imaging improves and as our knowledge of precursor lesions grows, we believe that EUS could become the most suitable method to detect curable pancreatic neoplasms in correctly identified asymptomatic at-risk patients.