Comprehensive review on endoscopic ultrasound-guided tissue acquisition techniques for solid pancreatic tumor

Pancreatic ductal adenocarcinoma is speculated to become the second leading cause of cancer-related mortality by 2030,a high mortality rate considering the number of cases.Surgery and chemotherapy are the main treatment options,but they are burdensome for patients.A clear histological diagnosis is needed to determine a treatment plan,and endoscopic ultrasound(EUS)-guided tissue acquisition(TA)is a suitable technique that does not worsen the cancer-specific prognosis even for lesions at risk of needle tract seeding.With the development of personalized medicine and precision treatment,there has been an increasing demand to increase cell counts and collect specimens while preserving tissue structure,leading to the development of the fine-needle biopsy(FNB)needle.EUS-FNB is rapidly replacing EUS-guided fine-needle aspiration(FNA)as the procedure of choice for EUS-TA of pancreatic cancer.However,EUS-FNA is sometimes necessary where the FNB needle cannot penetrate small hard lesions,so it is important clinicians are familiar with both.Given these recent developments,we present an up-to-date review of the role of EUS-TA in pancreatic cancer.Particularly,technical aspects,such as needle caliber,negative pressure,and puncture methods,for obtaining an adequate specimen in EUS-TA are discussed.

Endoscopic ultrasound assessment and tissue acquisition of mediastinal and abdominal lymph nodes

The differential diagnosis between benign and malignant lymph nodes(LNs)has a fundamental role in the characterization and staging of malignant conditions,as well as in subsequent patients’management.All imaging modalities(i.e.computed tomography and magnetic resonance imaging)rely mainly on size;endoscopic ultrasound(EUS)criteria based on B-mode evaluation and Doppler features fail to adequately characterize with high specificity LNs nature.The introduction of EUS-elastography and contrast-enhanced harmonic EUS are useful techniques to increase the diagnostic yield in identifying metastatic LNs,to identify which suspicious LN should require pathological characterization and,finally,to target tissue acquisition.EUS-guided tissue acquisition(EUS-TA)is increasingly being used for diagnosing lymphadenopathy whenever the characterization modifies patients’subsequent management and when no superficial LN is accessible.Since target therapy are currently available(i.e.lung cancer,breast cancer),EUS-TA of malignant LNs could be required to identify tumor biology.In this field,both fine needle aspiration and biopsy needles are able to guarantee accurate results with almost perfect specificity and sub-optimal sensitivity.We finally propose a diagnostic algorithm based on most recent,high-level evidence for the diagnostic approach to suspected LNs assessment.

Endoscopic ultrasound guided fine needle aspiration and useful ancillary methods

The role of endoscopic ultrasound(EUS) in evaluating pancreatic pathology has been well documented from the beginning of its clinical use. High spatial resolution and the close proximity to the evaluated organs within the mediastinum and abdominal cavity allow detection of small focal lesions and precise tissue acquisition from suspected lesions within the reach of this method. Fine needle aspiration(FNA) is considered of additional value to EUS and is performed to obtain tissue diagnosis. Tissue acquisition from suspected lesions for cytological or histological analysis allows, not only the differentiation between malignant and non-malignant lesions, but, in most cases, also the accurate distinction between the various types of malignant lesions. It is well documented that the best results are achieved only if an adequate sample is obtained for further analysis, if the material is processed in an appropriate way, and if adequate ancillary methods are performed. This is a multi-step process and could be quite a challenge in some cases. In this article, we discuss the technical aspects of tissue acquisition by EUS-guided-FNA(EUS-FNA), as well as the role of an on-site cytopathologist, various means of specimen processing, and the selection of the appropriate ancillary method for providing an accurate tissue diagnosis and maximizing the yield of this method. The main goal of this review is to alert endosonographers, not only to the different possibilities of tissue acquisition, namely EUS-FNA, but also to bring to their attention the importance of proper sample processing in the evaluation of various lesions in the gastrointestinal tract and other accessible organs. All aspects of tissue acquisition(needles, suction, use of stylet, complications, etc.) have been well discussed lately. Adequate tissue samples enable comprehensive diagnoses, which answer the main clinical questions, thus enabling targeted therapy.

Endoscopic ultrasound fine needle aspiration vs fine needle biopsy in solid lesions:A multi-center analysis

BACKGROUND While endoscopic ultrasound(EUS)-guided fine needle aspiration(FNA)is considered a preferred technique for tissue sampling for solid lesions,fine needle biopsy(FNB)has recently been developed.AIM To compare the accuracy of FNB vs FNA in determining the diagnosis of solid lesions.METHODS A retrospective,multi-center study of EUS-guided tissue sampling using FNA vs FNB needles.Measured outcomes included diagnostic test characteristics(i.e.,sensitivity,specificity,accuracy),use of rapid on-site evaluation(ROSE),and adverse events.Subgroup analyses were performed by type of lesion and diagnostic yield with or without ROSE.A multivariable logistic regression was also performed.RESULTS A total of 1168 patients with solid lesions(n=468 FNA;n=700 FNB)underwent EUS-guided sampling.Mean age was 65.02±12.13 years.Overall,sensitivity,specificity and accuracy were superior for FNB vs FNA(84.70%vs 74.53%;99.29%vs 96.62%;and 87.62%vs 81.55%,respectively;P<0.001).On subgroup analyses,sensitivity,specificity,and accuracy of FNB alone were similar to FNA+ROSE[(81.66%vs 86.45%;P=0.142),(100%vs 100%;P=1.00)and(88.40%vs 85.43%;P=0.320].There were no difference in diagnostic yield of FNB alone vs FNB+ROSE(P>0.05).Multivariate analysis showed no significant predictor for better accuracy.On subgroup analyses,FNB was superior to FNA for non-pancreatic lesions;however,there was no difference between the techniques among pancreatic lesions.One adverse event was reported in each group.CONCLUSION FNB is superior to FNA with equivalent diagnostic test characteristics compared to FNA+ROSE in the diagnosis of non-pancreatic solid lesions.Our results suggest that EUS-FNB may eliminate the need of ROSE and should be employed as a first-line method in the diagnosis of solid lesions.