Endoscopic ultrasound-guided biopsies vs surgical specimens for establishing patient-derived pancreatic cancer organoids: A systematic review and meta-analysis.

BACKGROUND AND AIMS: Patient-Derived Tumor Organoids (PDTOs) is a promising new disease model in pancreatic cancer for use in personalized medicine, but overall success rate (SR) of establishing these cultures from endoscopic ultrasound-guided biopsies is unknown. METHODS: We searched relevant databases publications reporting SR of PDTO establishment from pancreatic cancer. The primary outcome was SR stratified on tissue acquisition method (EUS-guided biopsies, percutaneous biopsies, and surgical specimens). RESULTS: We identified 24 studies including 1,053 attempts at establishing PDTOs. Overall SR was 63% (95% CI: 54%-72%). Pooled SR of PDTO establishment from EUS-guided biopsies, percutaneous biopsies, and surgical specimens were 60% (95% CI: 43-76%), 36% (95% CI: 14-61%) and 62% (95% CI: 48-75%), respectively and did not differ significantly (p = 0.1975). CONCLUSION: The SR of PDTO establishment from EUS-guided biopsies is comparable to surgical specimens. Both techniques are suitable for tissue acquisition for PDTOs in clinical and research settings.

Tissue amount and diagnostic yield of a novel franseen EUS-FNB and a standard EUS-FNA needle-A randomized controlled study in solid pancreatic lesions.

Background and Objectives: Several types of needles are available for EUS-guided tissue sampling of pancreatic lesions. Whereas fine-needle aspiration (FNA) needles typically provide cytological samples, fine-needle biopsy (FNB) needles are designed to obtain microcores with preserved tissue architecture. The aim of this study was to compare tissue amount and diagnostic yield between a modified Franseen-type FNB needle (TopGain; Medi-Globe GmbH, Grassau, Germany) and a standard FNA needle. Methods: We performed a prospective, multicenter randomized controlled study between June 2020 and September 2021, including patients with a solid pancreatic lesion referred for EUS-guided tissue sampling at 3 centers in Denmark. The patients were randomized 1:1 to either FNA needle or the novel FNB needle. Primary outcomes included the number of obtained tissue microcores and total and diagnostic tissue area. Results: Sixty-four patients were included. The median number of tissue microcores procured per pass was significantly higher in the FNB group compared with FNA (3 vs. 2, P < 0.001). Similarly, the mean total tissue area (2.74 vs. 0.44 mm2, P < 0.001) and mean diagnostic tissue area (1.74 vs. 0.28 mm2, P < 0.001) were more than 6-fold larger in the FNB samples compared with FNA. The median number of passes needed for a diagnostic sample was 1 for the FNB needle and 2 for FNA needle (P = 0.12). The novel FNB needle provided a higher percentage of samples of excellent quality (P = 0.002). Conclusions: The novel Franseen-type FNB needle seems to be significantly superior to a conventional FNA needle. The results of this study underline excellent performance of crown-cut needles.

Validation of a Novel EUS-FNB-Derived Organoid Co-Culture System for Drug Screening in Patients with Pancreatic Cancer.

Cancer-associated fibroblasts (CAFs) have been shown to impact the chemosensitivity of patient-derived tumor organoids (PDTOs). However, the published literature comparing PDTO response to clinical outcome does not include CAFs in the models. Here, a co-culture model was created using PDTOs and CAFs derived from endoscopic ultrasound-guided fine-needle biopsies (EUS-FNBs) for potential use in drug screening applications. Co-cultures were established, and growth was compared to monocultures using image metrics and a commercially available assay. We were able to establish and expand validated malignant PDTOs from 19.2% of adenocarcinomas from EUS-FNBs. CAFs could be established from 25% of the samples. The viability of PDTOs in the mixed cell co-culture could be isolated using image metrics. The addition of CAFs promoted PDTO growth in half of the established co-cultures. These results show that co-cultures can be established from tiny amounts of tissue provided by EUS-FNB. An increased growth of PDTOs was shown in co-cultures, suggesting that the present setup successfully models CAF-PDTO interaction. Furthermore, we demonstrated that standard validation techniques may be insufficient to detect contamination with normal cells in PDTO cultures established from primary tumor core biopsies.

Targeted next-generation sequencing of EUS-guided through-the-needle-biopsy sampling from pancreatic cystic lesions.

BACKGROUND AND AIMS: Recent advances have introduced molecular subtyping of pancreatic cystic lesions (PCLs) as a possible amendment to the diagnostic algorithm. The study evaluated the feasibility and diagnostic accuracy of molecular analysis and subtyping of PCLs using the recently introduced EUS-guided through-the-needle-biopsy (TTNB) sampling. METHODS: We prospectively included 101 patients in the study who presented with PCLs >15 mm in the largest cross-section. EUS-guided TTNB samples were obtained by a micro-biopsy forceps introduced through a 19-gauge needle. The TTNB samples were analyzed by next-generation sequencing (NGS) for point mutations in tumor suppressors and oncogenes using a 51-gene customized hotspot panel. Sensitivity and specificity were calculated with the histologic diagnosis as reference. RESULTS: After initial microscopic evaluation of the samples, 91 patients had residual TTNB samples available for NGS. Of these, 49 harbored mutations, most frequently in KRAS and GNAS, reflecting an excess frequency of intraductal papillary mucinous neoplasms (IPMNs) in the study population. A sensitivity and specificity of 83.7% (95% confidence interval [CI], 70.3-92.7) and 81.8% (95% CI, 48.2-97.7), respectively, were demonstrated for the diagnosis of a mucinous cyst and 87.2% (95% CI, 74.2-95.2) and 84.6% (95% CI, 54.5-98.1) for the diagnosis of an IPMN. CONCLUSIONS: Thus, molecular analysis of TTNB samples by NGS has high sensitivity and specificity for diagnosing mucinous cysts and IPMNs. Although the procedure comes with a risk of adverse events of 9.9%, TTNB samples are a robust alternative to cyst fluid for a combined histologic and molecular diagnosis of PCLs. (Clinical trial registration number: NCT03578445.).

EUS-guided biopsy versus confocal laser endomicroscopy in patients with pancreatic cystic lesions: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Pancreatic cystic lesions (PCLs) are frequent incidental findings on cross-sectional imaging and represent a diagnostic challenge as different kinds of PCLs harbor a dissimilar risk of malignancy. Two diagnostic tools have recently been developed and introduced: through-the-needle biopsy (TTNB) and needle-based confocal laser endomicroscopy (nCLE). The aim of this meta-analysis was to compare the diagnostic yield and performance, as well as the safety profile of the two methods. METHODS: This meta-analysis was performed in accordance with the PRISMA statement. Medline, Embase, Web of Science, and Cochrane Library databases were searched for studies with five or more patients undergoing either endoscopic ultrasound (EUS)-TTNB or EUS-nCLE for a PCL. Reviews, case reports, editorials, conference abstracts, and studies on exclusively solid pancreatic lesions were excluded. Outcomes of interest were diagnostic yield and performance, safety, and technical success. RESULTS: Twenty studies with 1023 patients were included in the meta-analysis. Pooled diagnostic yield of EUS-nCLE was higher compared to EUS-TTNB (85% vs. 74%, P < 0.0001), while diagnostic performance was high and comparable for both methods (pooled sensitivity: 80% vs. 86% and pooled specificity: 80% vs. 83% for TTNB and nCLE, respectively, P > 0.05). Pooled estimate of total adverse event (AE) rate was 5% in the TTNB group and 3% in the nCLE group, P = 0.302. Technical success rates were high and comparable (94% and 99% for EUS-TTNB and nCLE, respectively; P = 0.07). CONCLUSION: EUS-TTNB and EUS-nCLE have a similar safety profile with a relatively low number of AEs. Technical success, sensitivity, and specificity are comparable; however, EUS-nCLE seems to have a slightly higher diagnostic yield.

Diagnostic accuracy of EUS-guided through-the-needle-biopsies and simultaneously obtained fine needle aspiration for cytology from pancreatic cysts: A systematic review and meta-analysis.

OBJECTIVES: To address the diagnostic accuracy of endoscopic ultrasound guided through-the-needle-biopsies (TTNBs) and simultaneously obtained cytology samples from pancreatic cysts compared to the final histopathological diagnosis of the surgical specimen, and to give an overview of ancillary tests performed on TTNBs. METHODS: A literature search was conducted in MEDLINE, Embase and Scopus. Studies were included in the meta-analysis, if they had data for TTNB, cytology and a surgical specimen of pancreatic cysts as reference standard. The assessment of the risk of bias and quality of the included studies was conducted using the modified QUADAS-2 tool. RESULTS: Ten studies with 99 patients were included in the meta-analysis. Data regarding study design and clinicopathological features were extracted systematically. For TTNB, pooled sensitivity was 0.86 (95 % CI 0.62-0.96), specificity 0.95 (95 % CI 0.79-0.99) and area under the curve (AUC) 0.86 for the diagnosis of a mucinous cyst and pooled sensitivity was 0.78 (95 % CI 0.61-0.89), specificity 0.99 (95 % CI 0.90-0.99) and AUC 0.92 for the diagnosis of a high-risk cyst. For a specific diagnosis, pooled sensitivity was 0.69 (95 % CI 0.50-0.83), specificity 0.47 (95 % CI 0.28-0.68) and AUC 0.49. For cytology performed simultaneously, pooled sensitivity was 0.46 (95 % CI 0.35-0.57), specificity 0.90 (95 % CI 0.46-0.99) and AUC 0.64 for the diagnosis of mucinous cysts, and pooled sensitivity was 0.38 (95 % CI 0.23-0.55), specificity 0.99 (95 % CI 0.90-0.99) and AUC 0.84 for the diagnosis of a high-risk cyst. For a specific diagnosis, pooled sensitivity was 0.29 (95 % CI 0.21-0.39), specificity 0.45 (95 % CI 0.25-0.66) and AUC 0.30. Furthermore, immunohistochemical stains can be useful to establish the specific cyst subtype. CONCLUSIONS: TTNBs have a higher sensitivity and specificity than cytology for the diagnosis of mucinous cyst and high- risk cysts of the pancreas.

Clinical impact of endoscopic ultrasound-guided through-the-needle microbiopsy in patients with pancreatic cysts.

BACKGROUND: The limited data on the utility of endoscopic ultrasound (EUS)-guided through-the-needle biopsies (TTNBs) in patients with pancreatic cystic lesions (PCLs) originate mainly from retrospective studies. Our aim was to determine the clinical impact of TTNBs, their added diagnostic value, and the adverse event rate in a prospective setting. METHODS: This was a prospective, single-center, open-label controlled study. Between February 2018 and August 2019, consecutive patients presenting with a PCL of 15 mm or more and referred for EUS were included. Primary outcome was a change in clinical management of PCLs following TTNB compared with cross-sectional imaging and cytology. Adverse events were defined according to the ASGE lexicon. RESULTS: 101 patients were included. TTNBs led to a change in clinical management in 11.9 % of cases (n = 12). Of these, 10 had serous cysts and surveillance was discontinued, while one of the remaining two cases underwent surgery following diagnosis of a mucinous cystic neoplasm. The diagnostic yield of TTNBs for a specific cyst diagnosis was higher compared with FNA cytology (69.3 % vs. 20.8 %, respectively; P < 0.001). The adverse event rate was 9.9 % (n = 10; 95 % confidence interval 5.4 % - 17.3 %), with the most common event being acute pancreatitis (n = 9). Four of the observed adverse events were severe, including one fatal outcome. CONCLUSIONS: TTNBs resulted in a change of clinical management in about one in every 10 patients; however, the associated adverse event risk was substantial. Further studies are warranted to elucidate in which subgroups of patients the clinical benefit outweighs the risks.

Diagnostic performance of current guidelines and postoperative outcome following surgical treatment of cystic pancreatic lesions - a 10-year single center experience.

OBJECTIVE: Pancreatic cystic lesions (PCLs) are diagnostically challenging and there are currently several different guidelines. The aim of this study was to compare diagnostic performance of the most widely utilized International Association of Pancreatology (IAP) guidelines and the recent evidence-based European guidelines and to report on postoperative outcomes following surgical treatment of PCLs. METHODS: This is a retrospective single-center study of patients undergoing surgery due to a PCL between 2010 and 2019. Primary outcome was a comparison of diagnostic performance between IAP and European guidelines, measured in area under the receiver operating characteristic curve (AUC). Other outcomes included diagnostic performance of different risk features, 30-day postoperative mortality and major morbidity, final diagnosis, and overall survival. RESULTS: We identified 137 patients, three of whom did not undergo curative surgery due to metastatic disease. Overall, there was no difference in the performance of the two guidelines with AUC values ranging from 0.572-0.610 and 0.607-0.621 for IAP and European guidelines respectively. Postoperative 30-day mortality and major morbidity were 0% (95% CI 0.0-2.7%) and 37.3% (95% CI 29.1-46.1%), respectively. More than half of the resected lesions (52.6%) were low-grade dysplastic or non-neoplastic. CONCLUSIONS: Overall, the IAP and the European guidelines performed equally, although European guidelines had a slightly higher mean specificity. Pancreatic surgery is associated with high major morbidity, and there is a need for new diagnostic tools and strategies in order to decrease the amount of overtreatment in patients with PCL.

EUS-guided through-the-needle microbiopsy of pancreatic cysts: Technical aspects (with video).

Pancreatic cystic lesions are frequently encountered and diagnostically challenging as some of the cysts may have malignant potential (mucinous) while others are completely benign (serous). EUS-guided through-the-needle biopsy (EUS-TTNB) of the cyst wall has recently been introduced as an alternative to cyst fluid cytology. Several studies have shown that microbiopsies outperform cytology in terms of distinction between mucinous and nonmucinous lesions, but also in determining the specific cyst diagnosis. However, little is known about the technical aspects of tissue sampling with TTNB. Herein, we summarize our experience with the procedure in a tertiary referral center and discuss indications, technical aspects, and safety of the procedure. Most adverse events (AEs) associated with the procedure are mild, but there is emerging evidence that the rate of postprocedural pancreatitis is higher compared to standard fine-needle aspiration. The added diagnostic yield should therefore be placed in perspective with an increased risk of AEs. Prospective studies are warranted to fully identify which patient groups could benefit from EUS-TTNB.

Therapeutic thresholds and mechanisms for primary non-response to infliximab in inflammatory bowel disease.

BACKGROUND: Primary non-response to infliximab (IFX) inherits a poor prognosis in inflammatory bowel disease (IBD). We explored underlying mechanisms and therapeutic thresholds in an effort to provide basis for optimizing therapy. METHODS: A prospectively followed cohort of 166 IBD patients having received standard IFX induction therapy (5 mg/kg at weeks 2, 6, and 14) had trough IFX and anti-IFX antibodies (Abs) retrospectively assessed at weeks 2 (n = 148) and 6 (n = 108). Circulating TNFα was measured in matched primary non-responders (n = 29) and responders (n = 21) at baseline and weeks 6 and 14. Clinical outcome at week 14 was supported by disease activity scores in half of patients. RESULTS: In all, 18 patients (11%) had primary non-response. Infliximab was consistently lower throughout the induction phase in non-responders as compared to responders (Week 2: IFX median 18.9 µg/mL vs. 23.3, p < .05. Week 6: 8.4 vs. 17.0, p < .05). Optimal IFX thresholds associated with response was 22.9 µg/mL at week 2 (sensitivity 51%, specificity 80%, AUCROC 0.67, p < .05) and 11.8 at week 6 (72%, 77%, 0.71, p < .05). Anti-IFX Abs occurred in 28% of primary non-responders and associated with low IFX and treatment failure (OR 13.7 [2.8-67.5], p < .01). Markers of disease activity (disease activity scores, albumin, CRP) also associated with low IFX. Circulating TNFα was higher throughout induction in non-responders with ulcerative colitis but not Crohn's disease. CONCLUSION: IBD patients with primary IFX failure generally have lower IFX trough than responders during early induction phase. Pharmacokinetic failure seems common in ulcerative colits, whereas pharmacodynamic failure appears common in Crohn's disease.

DNA sequencing of cytopathologically inconclusive EUS-FNA from solid pancreatic lesions suspicious for malignancy confirms EUS diagnosis.

BACKGROUND AND OBJECTIVES: EUS-FNA is inconclusive in up to 10%-15% of patients with solid pancreatic lesions (SPLs). We aimed to investigate whether supplementary genetic analyses with whole-exome sequencing add diagnostic value in patients with SPLs suspicious of malignancy but inconclusive EUS-FNA. PATIENTS AND METHODS: Thirty-nine patients, who underwent EUS-FNA of an SPL were retrospectively included. Three groups were defined: 16 (41.0%) had suspected malignancy on EUS confirmed by cytology (malignant), 13 (33.3%) had suspected malignancy on EUS but benign cytology (inconclusive), and 10 (25.6%) had benign EUS imaging and cytology (benign). Areas with the highest epithelial cell concentrations were macro-dissected from the FNA smears from each patient, and extracted DNA was used for whole-exome sequencing by next-generation sequencing of a selected gene panel including 19 genes commonly mutated in cancer. RESULTS: Pathogenic mutations in K-RAS, TP53, and PIK3CA differed significantly between the three groups (P < 0.001, P = 0.018, and P = 0.026, respectively). Pathogenic mutations in KRAS and TP53 were predominant in the inconclusive (54% and 31%, respectively) and malignant groups (81.3% and 50%, respectively) compared to the benign group (0%). Malignant and inconclusive diagnoses correlated strongly with poor overall survival (P < 0.001). CONCLUSION: Whole-exome sequencing of genes commonly mutated in pancreatic cancer may be an important adjunct in patients with SPLs suspicious for malignancy on EUS but with uncertain cytological diagnosis.

Next-generation sequencing of endoscopic ultrasound guided microbiopsies from pancreatic cystic neoplasms.

AIMS: Interpretation of cytology samples from pancreatic cysts is challenging. A novel microbiopsy forceps used during endoscopic ultrasound examinations offers new opportunities for histological examination of tissue from pancreatic cysts as well as next-generation sequencing. The aim of this study was to analyse the results of next-generation sequencing of microbiopsies from pancreatic cysts. METHODS AND RESULTS: Microbiopsies from 27 patients were obtained, 23 of which were subjected to next-generation sequencing. Sixteen intraductal papillary mucinous neoplasms harboured mutations in genes regulating cell cycle and repair, and three were without mutations. Most frequent mutations were found in the KRAS and GNAS genes, and these were often concomitant. Three serous cystic neoplasms were without mutations, while with regard to histology, a non-diagnostic microbiopsy harboured a KRAS and a TP53 mutation and was deemed malignant after clinical follow-up. Three patients underwent surgery, and the point mutations detected in the microbiopsies were confirmed in the resected specimens. We identified one resected sample with an additional GNAS mutation which was not identified in the microbiopsy. CONCLUSIONS: Next-generation sequencing of microbiopsies may have the potential to improve diagnostic decision-making.

Subtyping of intraductal papillary mucinous neoplasms - pitfalls of MUC1 immunohistochemistry.

Intraductal papillary mucinous neoplasms (IPMNs) are precursor lesions of pancreatic ductal adenocarcinoma (PDAC). Current edition of WHO Classification of Tumors of the Digestive System recognizes four different subtypes (gastric, intestinal, pancreatobiliary, and oncocytic) and recommends analysis of mucin expression (MUC1, MUC2, MUC5AC, MUC6) as well as evaluation of architectural and cell differentiation patterns for correct classification. However, there is no consensus on MUC1 expression of IPMN-lesions in the literature. Current recommendations are based on studies where antibodies against the core MUC1 protein or sialylated MUC1 (tumor associated MUC1), not the fully glycosylated MUC1 were used. We have recently reported that MUC1 is strongly expressed in both gastric and intestinal types IPMN specimens from the cystic wall, obtained by endoscopic ultrasound guided microbiopsy procedure. We have used a commercial MUC1 antibody, validated and recommended for diagnostic use, which recognizes fully glycosylated MUC1. Based on the above, we propose a revision of the WHO Classification, specifying that antibodies against tumor associated MUC1 should be used for IPMN subtyping.

Initial experience with EUS-guided microbiopsy forceps in diagnosing pancreatic cystic lesions: A multicenter feasibility study (with video).

BACKGROUND AND OBJECTIVES: Cystic lesions of the pancreas represent a diagnostic dilemma. Recently, a through-the-needle microbiopsy forceps has become available, enabling procurement of EUS-guided histological specimens from the pancreatic cyst wall. The aim of this study was to evaluate the use of this novel instrument in a multicenter clinical setting. PATIENTS AND METHODS: Patients referred for EUS evaluation of pancreatic cysts and attempted EUS-guided microbiopsy was included retrospectively from six international tertiary centers. Patient's demographics, EUS findings, technical and clinical success, and histopathological results were recorded. RESULTS: : A total of 28 patients were identified. We report a technical success rate of 85.7% (n = 24). Biopsies were generally of good quality and contributed to the diagnosis in 20 patients (clinical success of 71.4%). Three adverse events were recorded (10.7%). CONCLUSIONS: The use of the microbiopsy forceps is feasible with acceptable rates of technical and clinical success. Prospective studies are warranted to determine the diagnostic potential compared to the other modalities. However, the results from this preliminary study are promising.

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.