Increased diagnostic yield of endoscopic ultrasound-guided fine needle aspirates with flow cytometry and immunohistochemistry

Pancreatic Adenocarcinoma: Improving Prevention and Survivorship

Pancreatic cancer is a growing problem in oncology, given slowly rising incidence and continued suboptimal outcomes. A concerted effort to reverse this tide will require prevention, early diagnosis, and improved systemic therapy for curable disease. We focus on these aspects in detail in this study. Hereditary pancreatic cancer is an underappreciated area. With the growing use of genomics (both somatic and germline) in cancer care, there is increasing recognition of hereditary pancreatic cancer cases: around 10% of all pancreatic cancer may be related to familial syndromes, such as familial atypical multiple mole and melanoma (FAMMM) syndrome, hereditary breast and ovarian cancer, Lynch syndrome, and Peutz-Jeghers syndrome. Screening and surveillance guidelines by various expert groups are discussed. Management of resectable pancreatic cancer is evolving; the use of multiagent systemic therapies, in the adjuvant and neoadjuvant settings, is discussed. Current and emerging data, along with ongoing clinical trials addressing important questions in this area, are described. Surveillance recommendations based on latest ASCO guidelines are also discussed. Finally, the multimodality management of borderline resectable pancreatic cancer is discussed. The various clinicoanatomic definitions of this entity, followed by consensus definitions, are described. Then, we focus on current opinions and practices around neoadjuvant therapy, discussing chemotherapy and radiation aspects, and the role of surgical resection.

Cell-block procedure in endoscopic ultrasound-guided-fine-needle-aspiration of gastrointestinal solid neoplastic lesions

In the present review we have analyzed the clinical applications of endoscopic ultrasound-guided-fine-needle-aspiration (EUS-FNA) and the methodological aspects obtained by cell-block procedure (CBP) in the diagnostic approach to the gastrointestinal neoplastic pathology. CBP showed numerous advantages in comparison to the cytologic routine smears; in particular, better preservation of cell architecture, achievement of routine haematoxylin-eosin staining equivalent to histological slides and possibility to perform immunohistochemistry or molecular analyses represented the most evident reasons to choose this method. Moreover, by this approach, the differential diagnosis of solid gastrointestinal neoplasias may be more easily achieved and the background of contaminant non-neoplastic gastrointestinal avoided. Finally, biological samples collected by EUS-FNA CBP-assisted should be investigated in order to identify and quantify further potential molecular markers.

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-guided fine needle aspiration: from the past to the future

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a technique which allows the study of cells obtained through aspiration in different locations near the gastrointestinal tract. EUS-FNA is used to acquire tissue from mucosal/submucosal tumors, as well as peri-intestinal structures including lymph nodes, pancreas, adrenal gland, gallbladder, bile duct, liver, kidney, lung, etc. The pancreas and lymph nodes are still the most common organs targeted in EUS-FNA. The overall accuracy of EUS is superior to computed tomography scan and magnetic resonance imaging for detecting pancreatic lesions. In most cases it is possible to avoid unnecessary surgical interventions in advanced pancreatic cancer, and EUS is considered the preferred method for loco-regional staging of pancreatic cancer. FNA improved the sensitivity and specificity compared to EUS imaging alone in detection of malignant lymph nodes. The negative predictive value of EUS-FNA is relatively low. The presence of a cytopathologist during EUS-FNA improves the diagnostic yield, decreasing unsatisfactory samples or need for additional passes, and consequently the procedural time. The size of the needle is another factor that could modify the diagnostic accuracy of EUS-FNA. Even though the EUS-FNA technique started in early nineteen's, there are many remarkable progresses culminating nowadays with the discovery and performance of needle-based confocal laser endomicroscopy. Last, but not least, identification and quantification of potential molecular markers for pancreatic cancer on cellular samples obtained by EUS-FNA could be a promising approach for the diagnosis of solid pancreatic masses.

Immunophenotyping of paucicellular samples

Immunophenotyping of paucicellular samples may represent a diagnostic challenge in the flow cytometry (FC) laboratory routine, as the scarcity of cells limits the number of tests that can be performed. Specimens such as fine needle aspirates (FNA), human body fluids (BF), cerebrospinal fluid (CSF), or ocular fluid (OF) sent for FC investigations in the case of suspicion of lymphoma, or for lymphoma monitoring, may contain very low numbers of cells. In these cases, it is mandatory to obtain the largest amount possible of useful information from a single tube. The basic protocol described in this unit provides a method that combines the use of multiple monoclonal antibodies (MAbs) with a Boolean gating strategy to identify and quantify the main lymphocyte populations, as well as to detect lymphomatous B cells or any aberrant T cell expression, if present, in paucicellular samples.

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.

Health resource utilization and multidisciplinary impact of endoscopic ultrasonography in a tertiary referral medical center

BACKGROUND

Endoscopic ultrasound (EUS) is a resource-intensive endoscopic procedure, but may result in high downstream health resource utilization and multispecialty impact. Our aim was to examine the downstream impact of EUS by specialty and by indication.

METHODS

A retrospective chart review was performed at an academic medical center for patients for whom EUS represented the first point of contact at the study institution within a 20-month period.

RESULTS

A total of 552 EUS procedures were reviewed and 208 represented the first point of contact. The most common principle indication involved the pancreas (n = 117, 56%). Downstream health utilization was calculated for an average of 313 days postprocedure (range: 35-632 days). Following unique referral for endoscopic ultrasound, 52% of the patients in the study were retained within the institution for further management and, of these, 34% had a major intervention in the form of surgery or chemoradiotherapy. Compared with other indications, patients presenting with a pancreatic mass were significantly more likely to remain in the study institution for further management (62% versus 39%, p = 0.005), were more likely to have a downstream surgery (29% versus 14%, p = 0.020) and were more likely to have downstream chemo-radiotherapy (11% versus 3%, p = 0.012).

CONCLUSIONS

EUS represents a unique portal of entry into tertiary referral medical centers. First point of contact EUS referrals are associated with major downstream health resource utilization and significantly increased utilization for mass lesions of the pancreas.