Endoscopic ultrasound

Linear endoscopic ultrasound: Current uses and future perspectives in mediastinal examination

This editorial elaborates on the current and future applications of linear endoscopic ultrasound (EUS), a substantial diagnostic and therapeutic modality for various anatomical regions. The scope of endosonographic assessment is broad and, among other factors, allows for the evaluation of the mediastinal anatomy and related pathologies, such as mediastinal lymphadenopathy and the staging of central malignant lung lesions. Moreover, EUS assessment has proven more accurate in detecting small lesions missed by standard imaging examinations, such as computed tomography or magnetic resonance imaging. We focus on its current uses in the mediastinum, including lung and esophageal cancer staging, as well as evaluating mediastinal lymphadenopathy and submucosal lesions. The editorial also explores future perspectives of EUS in mediastinal examination, including ultrasound-guided therapies, artificial intelligence integration, advancements in mediastinal modalities, and improved diagnostic approaches for various mediastinal lesions.

Applications and Prospects of Artificial Intelligence-Assisted Endoscopic Ultrasound in Digestive System Diseases

Endoscopic ultrasound (EUS) has emerged as a widely utilized tool in the diagnosis of digestive diseases. In recent years, the potential of artificial intelligence (AI) in healthcare has been gradually recognized, and its superiority in the field of EUS is becoming apparent. Machine learning (ML) and deep learning (DL) are the two main AI algorithms. This paper aims to outline the applications and prospects of artificial intelligence-assisted endoscopic ultrasound (EUS-AI) in digestive diseases over the past decade. The results demonstrated that EUS-AI has shown superiority or at least equivalence to traditional methods in the diagnosis, prognosis, and quality control of subepithelial lesions, early esophageal cancer, early gastric cancer, and pancreatic diseases including pancreatic cystic lesions, autoimmune pancreatitis, and pancreatic cancer. The implementation of EUS-AI has opened up new avenues for individualized precision medicine and has introduced novel diagnostic and treatment approaches for digestive diseases.

Endoscopic Ultrasound (EUS) Guided Elastography

Endoscopic ultrasound (EUS) is an essential technique for the management of several diseases. Over the years, new technologies have been developed to improve and overcome certain limitations related to EUS-guided tissue acquisition. Among these new methods, EUS-guided elastography, which is a real-time method for the evaluation of tissue stiffness, has arisen as one of the most widely recognized and available. At present, there are available two different systems to perform an elastographic evaluation: strain elastography and shear wave elastography. Strain elastography is based on the knowledge that certain diseases lead to a change in tissue hardness while shear wave elastography monitored shear-wave propagation and measures its velocity. EUS-guided elastography has shown in several studies high accuracy in differentiating benign from malignant lesions from many different locations, mostly in the pancreas and lymph nodes. Therefore, nowadays, there are well-established indications for this technology, mainly for supporting the management of pancreatic diseases (diagnosis of chronic pancreatitis and differential diagnosis of solid pancreatic tumors) and characterization of different diseases. However, there are more data on new potential indications for the near future. In this review, we will present the theoretical bases of this technology and we will discuss the scientific evidence to support its use.

Endoscopic ultrasonography: Enhancing diagnostic accuracy

Endoscopic ultrasound (EUS) is an essential technique for the management of several diseases. Over the years, new technologies have been developed because to improve and overcome certain limitations related to EUS guided tissue acquisition. Among these new methods, EUS guided elastography and contrast enhanced EUS has arisen as the most widely recognized and available. We will review in this manuscript the different techniques of elastography and contrast enhancement. Nowadays, there are well establish indications for advance imaging, mainly for supporting the management of pancreatic diseases (diagnosis of chronic pancreatitis and differential diagnosis of solid and cystic pancreatic tumors) and characterization of lymph nodes. However, there are more data on new potential indications for the near future.

Sarcoidosis with Pancreatic Mass, Endobronchial Nodules, and Miliary Opacities in the Lung

Sarcoidosis affects multiple organs and rarely has unusual manifestations. A 78-year-old woman was referred to our hospital for coughing symptoms. A chest computed tomography (CT) scan revealed bilateral diffuse miliary patterns and right pleural effusion. Bronchoscopy showed multiple nodules in the carina and the bronchus intermedius. A CT scan of her abdomen revealed hypovascular lesions involving the pancreatic head and body. A transbronchial lung biopsy, bronchial mucosal biopsy, and endoscopic ultrasound-guided fine-needle aspiration of the pancreatic mass demonstrated non-caseating granulomas. We diagnosed the patient with sarcoidosis. She received no treatment for sarcoidosis and has been followed up for one year, during which no pulmonary disease progression had been observed and the pancreatic masses partially regressed.

New Imaging Techniques: Endoscopic Ultrasound-Guided Elastography

Endoscopic ultrasound (EUS) is a major imaging method in the management of several diseases of the gastrointestinal tract and surrounding structures. Elastography is a novel technique providing additional information to standard B-mode imaging on the tissue stiffness. Elastography can be performed under EUS guidance. This method has proven to be an accurate and additional tool in the evaluation of pancreatic diseases and lymph nodes analysis. Possible uses include the study of liver lesions, subepithelial masses, and many more. This article reviews current knowledge and future perspectives.

Predictors of pathologic upstaging in early esophageal adenocarcinoma: Results from the national cancer database

BACKGROUND

Upstaging in early esophageal adenocarcinoma (EAC) patients happens at a high rate and has implications for treatment. We sought to identify risk factors predicting upstaging.

STUDY DESIGN

The National Cancer Database (2010-2013) was queried for all patients with clinical T1/T2 and N0 EAC who underwent esophagectomy without neoadjuvant therapy. Logistic regression models were developed to investigate risk factors for upstaging.

RESULTS

A total of 1120 patients were included. Pathologic upstaging occurred in 21.3% (n = 239). After adjustment, risk of upstaging increased with tumor size (tumor size 1-3 cm, OR 4.57,95% CI 2.58-8.10, tumor size >3 cm, OR 10.57, 95% CI 5.77-19.35, as compared to tumors <1 cm) as well as with positive margins (OR 4.13, 95% CI 2.17-7.87) and > than 10 lymph nodes examined (OR 1.85, 95% CI 1.29-2.63), while facility volume was not significant. Odds of upstaging increased linearly with number of lymph nodes examined (OR 1.02 per node).

CONCLUSION

Our data underscore the importance of tumor size as a predictor for upstaging and of completing a thorough lymph node dissection for staging purposes.

Can elastography replace fine needle aspiration?

Endoscopic ultrasound (EUS) is one of the best diagnostic methods for diseases of the digestive tract and surrounding organs. Whereas EUS-guided fine needle aspiration (FNA) has been very useful for providing histological confirmation for previously hard to reach lesions, elastography is aiming to obtain a “virtual biopsy” by assessing differences in elasticity between the normal and pathological – usually malignant – tissue. A question that arises is whether EUS-elastography has reached a stage where it might successfully supplant the use of EUS-FNA in some of its clinical indications. The main indications of EUS-guided FNA are listed in this article and published data on the usage of elastography in these settings is reviewed for each one. In some of the indications, a plethora of studies have been published, notably for the evaluation of solid pancreatic masses and lymph nodes, while in others there is little relevant data (submucosal masses, left liver lesions, left adrenal masses), or elastography simply is not suitable as a diagnostic means (cystic lesions). Our conclusion is that elastography is not yet ready to replace EUS-FNA in its indications, but should complement it in various settings, especially for the assessment of lymph nodes. It can only be considered an alternative on a case-by-case basis, in situations where FNA is regarded as a contraindication. Furthermore, it could be used in conjunction with other imaging techniques, such as contrast-enhanced EUS, in order to further improve the accuracy of non-invasive EUS assessment, possibly making the case for a more limited or targeted use of EUS-FNA in selected cases.

Endoscopic ultrasound is inadequate to determine which T1/T2 esophageal tumors are candidates for endoluminal therapies

OBJECTIVES

Esophageal endoscopic ultrasound is now regarded as essential in the staging of esophageal carcinoma. There is an increasing trend toward endoluminal therapies (ie, endoscopic mucosal resection and radiofrequency ablation) for pre-cancer or early-stage cancers because of concerns of high morbidity associated with esophagectomy. This study reviews our institutional experience with preoperative endoscopic ultrasound staging of early esophageal cancers in patients who underwent an esophagectomy to evaluate the accuracy of staging by endoscopic ultrasound and how this affects treatment recommendations.

METHODS

A prospective esophagectomy database of all patients undergoing an esophagectomy for esophageal cancer at a single high-volume institution was retrospectively reviewed for patients with early-stage esophageal cancer. This study analyzed patients with clinical Tis to T1 disease, as predicted by preoperative endoscopic ultrasound, and correlated this with the pathologic stages after esophagectomy. The surgical outcomes were evaluated to assess the safety of esophagectomy as a treatment modality.

RESULTS

From 2005 to 2011, 107 patients (93 male, 14 female) with a mean age of 66 years (range, 39-91 years) were staged by preoperative endoscopic ultrasound to have esophageal high-grade dysplasia, carcinoma in situ, or T1 cancer and underwent an esophagectomy. Tumor depth was correctly staged by endoscopic ultrasound in only 39% (23/59) of pT1a tumors (invading into the lamina propria or muscularis mucosa) and 51% (18/35) of pT1b tumors (submucosal). Of the endoscopic ultrasound-staged cT1a-lpN0 lesions, there were positive lymph nodes in 15% of pathologic specimens (2/13). Patients with pT1a-mm lesions had a 9% rate of pathologic lymph node involvement (1/11), and those with pT1b tumors had a 17% rate of lymph node spread (6/35). Esophagectomy was performed in all 107 patients with a 30-day mortality rate of less than 1% (1/107).

CONCLUSIONS

The sensitivity and specificity of endoscopic ultrasound for determining true pathologic staging are poor for early-stage esophageal cancers. Lesions thought to be cT1a-lpN0 by endoscopic ultrasound have at least pN1 disease in 15% of cases. Endoluminal therapy of these lesions based on endoscopic ultrasound undertreats a significant number of patients. Esophagectomy is still the standard therapy for early-stage esophageal cancers in the majority of patients.

Diagnostic bedside EUS in the intensive care unit: a single-center experience

BACKGROUND

The knowledge of bedside diagnostic EUS in critically ill patients is limited.

OBJECTIVE

To investigate the indications, feasibility, safety, and clinical utility of diagnostic EUS in the intensive care unit (ICU).

DESIGN

Retrospective.

SETTING

Tertiary-care referral teaching hospital.

PATIENTS

All consecutive patients who had EUS done in the ICU within a 6-year period.

INTERVENTION

Bedside EUS and EUS-guided FNA.

MAIN OUTCOME MEASUREMENTS

EUS indications, complications, and impact on management.

RESULTS

A total of 64 EUS procedures were performed in 63 patients (38 men, 25 women; age range 27-78 years); 1 patient underwent 2 separate EUS procedures. EUS was performed while the patients were mechanically ventilated in 70% (45/64) of cases. Indications for EUS included jaundice (n = 24), mass of unknown etiology (n = 25), unexplained pancreatitis (n = 7), and staging of known cancer (n = 3). In 5 cases, EUS was used as an alternative to other imaging modalities because of morbid obesity (n = 3) or contraindication to intravenous contrast material (n = 2). Complications included reversible oxygen desaturation (n = 4), nonsustained ventricular tachycardia (n = 1), and transient hypotension (n = 1). Overall, EUS influenced management in 97% (62/64) of cases.

LIMITATIONS

Retrospective, single-center study.

CONCLUSION

ICU-based EUS can be performed with few intraprocedural complications and can be a valuable diagnostic modality in the ICU setting. It appears to be particularly useful for determining the etiology of jaundice, masses of unknown etiology, and pancreatitis. It may have particular value as a diagnostic technique on selected patients with unstaged cancer and when morbid obesity or the inability to use intravenous contrast material precludes the use of other imaging modalities in the critically ill patient.

Endoscopic ultrasound elastography

Endoscopic ultrasound (EUS) is a reference technique for diagnosing and staging several different diseases. EUS-guided biopsies and fine needle aspirations are used to improve diagnostic performance of cases where a definitive diagnosis cannot be obtained through conventional EUS. However, EUS-guided tissue sampling requires experience and is associated with a low but not negligible risk of complications. EUS elastography is a non-invasive method that can be used in combination with conventional EUS and has the potential for improving the diagnostic accuracy and reducing the need for EUS-guided tissue sampling in several situations. Elastography measures tissue stiffness by evaluating changes in the EUS image before and after the application of slight pressure to the target tissue by the ultrasonography probe. Pathologic processes such as cancerization and fibrosis alter tissue elasticity and therefore induce changes in elastographic appearance. Qualitative elastography depicts tissue stiffness using different colors, whereas quantitative elastography renders numerical results expressed as a strain ratio or hue histogram mean. EUS elastography has been proven to differentiate between benign and malignant solid pancreatic masses, as well as between benign and malignant lymph nodes with a high accuracy. Studies have also demonstrated that the early changes of chronic pancreatitis can be distinguished from normal pancreatic tissues under EUS elastography. In this article, we review the technical aspects and current clinical applications of qualitative and quantitative EUS elastography and emphasize the potential additional indications that need to be evaluated in future clinical studies.

Endoscopic ultrasound image enhancement elastography

Endoscopic ultrasound (EUS) represents an advance in the diagnosis and staging of several diseases. EUS-guided fine-needle aspiration is useful, but technically demanding, and can be associated with complications. Elastography emerges as a useful tool that is based on the knowledge that some diseases, like cancer, lead to a modification in tissue stiffness. Elastography evaluates the elastic properties of tissues and compares images obtained before and after compression to target tissues; differentiating benign from malignant lesions. This article reviews theoretical aspects and the methodology of EUS elastography. Clinical applications, mainly in pancreatic diseases and lymph nodes, are analyzed.

The role of endoscopic ultrasound and cyst fluid analysis in the initial evaluation and follow-up of incidental pancreatic cystic lesions

PURPOSE

To assess the role of endoscopic ultrasound (EUS) in the initial evaluation and follow-up of incidental pancreatic cystic lesions (PCL).

METHODS

Retrospective analysis of patients with incidental PCL on imaging who were evaluated by EUS and had a minimal follow-up of 1 year.

RESULTS

There were 62 patients (40 females and 22 males). The mean patient age was 67.7 years (range, 30-89). The Median follow-up was 24 months (range, 12-72). The mean PCL size was 21.6 mm. In all, 13 patients underwent surgery (20.9%). Diagnosis included a mucinous cystic tumour (7), mucinous adenocarcinoma (2), intraductal papillary mucinous neoplasm (1) and a cystic neuroendocrine tumour (1). The overall malignancy rate among patients who underwent surgery was 15.3% (two patients). The mean carcinoembryonic antigen (CEA) level from PCL fluid analysis was also significantly higher in surgically treated group (7760) vs. the stable group (184.7) vs. the enlarging PCL group (361.1). A CEA level above 192 ng/ml predicted mucinous PCL with a sensitivity of 90%.

CONCLUSIONS

EUS with cystic fluid analysis can be successfully used to rule out pancreatic neoplasms and to follow-up incidentally discovered PCL.

Staging Accuracy of Endoscopic Ultrasound Based on Pathologic Analysis after Minimally Invasive Esophagectomy

Endoscopic ultrasonography (EUS) is a common staging modality used in patients with esophageal cancer. The objective of this analysis was to evaluate the accuracy and sensitivity of EUS in determining the depth of penetration (T stage) and nodal status (N stage) in patients with esophageal cancer who underwent minimally invasive esophagectomy (MIE). A retrospective analysis of all patients at a university hospital who underwent preoperative EUS followed by MIE for cancer was performed. We compared the results of preoperative EUS to final pathologic analyses of the esophageal specimen, examining the accuracy of EUS staging. Ninety-five patients with esophageal cancer who underwent MIE had preoperative EUS. Twenty-four of the 95 patients were excluded for lack of a repeat EUS after neoadjuvant therapy before resection. Hence, 71 patients were evaluated for the accuracy of EUS staging. The accuracy of EUS for TO disease was 80 per cent; T1 disease was 75 per cent; T2 disease was 39 per cent; and T3 disease was 88 per cent. The overall EUS accuracy for T stage was 72 per cent with overstaging occurring mostly for pathologic T1 tumors in 18 per cent and understaging occurring mostly for pathologic T3 tumors in 11 per cent. The sensitivity and specificity for detection of nodal involvement were 79 per cent and 74 per cent, respectively. However the accuracy for T and N staging by EUS after neoadjuvant therapy decreased to 63 per cent and 38 per cent, respectively. Endoscopic ultrasound in the absence of neoadjuvant therapy is a relatively accurate and sensitive modality for determining the depth of tumor penetration and the presence of nodal disease in patients with esophageal carcinoma. The accuracy for T and N staging is less reliable after neoadjuvant therapy.

Review of endoscopic ultrasound-guided fine-needle aspiration cytology

This review, based on the Hennepin County Medical Center experience and review of the literature, vastly covers the up-to-date role of endoscopic ultrasonography (EUS) and EUS-guided fine-needle aspiration (FNA) in evaluating tumorous lesions of the gastrointestinal tract and adjacent organs. Emphasis is given to the tumoral and nodal staging of esophageal, pulmonary, and pancreatic cancer. This review also discusses technical, pathological, and gastroenterologic aspects and the role of the pathologist and endosonographer in the evaluation of these lesions, as well as the corresponding FNA cytology and differential diagnosis.

Sampling of the adrenal glands by endoscopic ultrasound-guided fine-needle aspiration

Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) has proven to be a valuable modality for the primary diagnosis and staging of gastrointestinal, and perigastrointestinal malignancy. Aside from assessing thoracic and abdominal lymph nodes and the liver for metastases, EUS can assess and sample the adrenal glands, which are frequently involved by metastatic disease, but can also harbor benign primary neoplasms. The cytology files at our institution were reviewed for all cases of EUS-guided FNA of the adrenal glands. Clinical histories, sonographic findings, and cytologic findings of all cases were reviewed. Results were compared with overall EUS-guided FNA performance and the performance of non-EUS-guided FNA of the adrenal. The utility of cell block immunohistochemistry (IHC) in these cases was reviewed. Between 1/1/00 and 5/15/04 there were 24 cases of EUS-guided FNA of the adrenal gland from 22 different patients (13 men; 9 women) at our institution. This represented 1.4% of overall EUS-guided FNA and 77% of adrenal gland FNA. Patient ages ranged from 37 to 86 yr (mean 69 +/- 11 yr). Most patients had other cancers or mass lesions and were being staged at the time of the procedure (19 of 22). Almost all FNAs were of the left adrenal gland (23 of 24). Lesion size ranged from 0.9 to 7.9 cm (mean 2.5 +/- 1.6 cm). Diagnostic material was present in all cases when compared with an overall EUS-guided FNA diagnostic rate of 88%. Material for cell block was present in 21 cases, and IHC was used in 3 cases. Final diagnoses were as follows: cortical tissue consistent with cortical adenoma (19), metastatic adenocarcinoma (3), pheochromocytoma (1), and adrenal cortical carcinoma (1). EUS-guided FNA of the adrenal gland is primarily used in the staging of other malignancies when lesions of the left adrenal are recognized sonographically. Diagnostic tissue is easily obtained, including material for cell block IHC, which allows definitive diagnosis in cases that present difficult differential diagnoses.