Endoscopic ultrasound guided fine needle aspiration (EUS-FNA) of mediastinal lesions

Minimally Invasive Sampling of Mediastinal Lesions

This narrative review examines the existing literature on minimally invasive image-guided sampling techniques of mediastinal lesions gathered from international databases (Medline, PubMed, Scopus, and Google Scholar). Original studies, systematic reviews with meta-analyses, randomized controlled trials, and case reports published between January 2009 and November 2023 were included. Four authors independently conducted the search to minimize bias, removed duplicates, and selected and evaluated the studies. The review focuses on the recent advancements in mediastinal sampling techniques, including EBUS-TBNA, EUS-FNA and FNB, IFB, and nodal cryobiopsy. The review highlights the advantages of an integrated approach using these techniques for diagnosing and staging mediastinal diseases, which, when used competently, significantly increase diagnostic yield and accuracy.

Characterization of Lung Tumors that the Pulmonologist can Biopsy from the Esophagus with Endosonography (EUS-B-FNA)

BACKGROUND

According to guidelines, it is possible to biopsy lung tumors "immediately adjacent to the esophagus" with EUS-B-FNA. However, it is unknown what "immediately adjacent" exactly means.

OBJECTIVE

to investigate the possibility of achieving EUS-B-FNA biopsies from a lung tumor depending on the distance from the esophagus and to establish the maximal allowable distance between the tumor and the esophagus.

METHODS

In a prospective observational study, we included patients with a lung tumor located maximum 6 cm from the esophagus and indication of EUS-B-FNA from the tumor. The tumors were of different sizes. In a plot presenting the tumor size-distance relationship in cases with (biopsy) versus without (non-biopsy) successful EUS-B-FNA, a separation line representing the threshold between the groups were identified and a biopsy-index equation established. The maximal tumor-size corrected distance (TSCD) was calculated using the residuals to the separation line.

RESULTS

In total, 70 patients were included. EUS-B-FNA from the lung tumor was possible in 46 patients. All tumors with a distance from the esophagus below 19 mm could be biopsied. The maximal allowable esophagus-tumor distance depended on tumor size. From the separation line, a biopsy-index equation was established with the sensitivity of 93.5%, a specificity of 100%, and total accuracy of 95.7%. The TSCD was 31 mm (sensitivity: 95.7%, specificity 75.0%, and accuracy: 88.6%).

CONCLUSION

We established a biopsy-index equation to predict the achievability of a lung tumor using EUS-B-FNA depending on distance to esophagus and tumor size. A general maximal TSCD was 31 mm.

Role of endoscopic ultrasound-guided fine-needle aspiration in evaluating mediastinal and intra-abdominal lymphadenopathies of unknown origin

The aim of the present study was to evaluate the efficacy of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in diagnosing mediastinal and intra-abdominal lymphadenopathies. A total of 154 patients with mediastinal and intra-abdominal lymphadenopathies were included in this retrospective study between February 2010 and March 2015. Malignancy was suspected in the patients as a result of imaging findings and EUS-FNAs were performed to confirm the diagnoses. EUS and EUS-FNA data, as well as hospital medical records, were reviewed. The accuracy of EUS-FNA was 90.8% for diagnosing malignancy and 85.6% for diagnosing benign lymphadenopathy. In combination with flow cytometry (FCM), the accuracy of EUS-FNA to determine lymphoma was 94.2%. Among the malignant lymphadenopathy cases, 80 were caused by metastasis, 19 by lymphoma and 1 by myeloid leukemia. In the 53 benign cases, EUS-FNA revealed a nonspecific inflammatory condition in 27 patients, tuberculosis in 21 patients and Castleman's disease in 5 patients. The factors revealed to be associated with malignant lymphadenopathy included the sex and age of patients, as well as the location and size of the enlarged lymph node. In particular, celiac axis lymphadenopathy was associated with malignancy (23.0% of cases of malignancy, vs. 3.8% of benign lymphadenopathy). EUS-FNA results additionally suggested that the malignant lymph nodes observed in celiac axis were more likely to result from lymphoma (42.1%; 8/19 cases) than metastasis (18.8%; 15/80 cases; P=0.039). By contrast, malignant lymph nodes observed in the mediastinum were more likely to be caused by metastasis (47.5%; 38/80 cases) than lymphoma (10.5%; 2/19 cases; P=0.004). The results of the present study suggested that EUS-FNA is accurate for differentiating between malignancy and benign lymphadenopathy. Therefore, EUS-FNA in combination with FCM analysis, as a minimally invasive and highly sensitive tool, should be routinely performed for the identification of lymphoma. Additionally, examining the enlarged celiac axis lymph nodes of elderly males, who exhibit an increased risk of malignancy, may be beneficial.

Usefulness of endoscopic ultrasound-guided fine needle aspiration for lymphadenopathy

Lymphadenopathy may be difficult to diagnose using imaging results alone. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) may help to diagnose and determine the appropriate management of lymphadenopathy. EUS-FNA has been used as a safe and less invasive method for obtaining pathologic specimens from extraluminal lesions using endoscopic ultrasound. The present study evaluated the usefulness of EUS-FNA for lymphadenopathy. Between July 2013 and December 2016, 72 patients undergoing EUS-FNA for lymphadenopathy that could not be diagnosed solely using imaging were included. The present study evaluated the sensitivity, specificity, positive and negative predictive value, overall accuracy, helpfulness in determining the management of lymphadenopathy and EUS-FNA-associated complications. Of the 72 included patients, 8 were diagnosed with benign (inflammatory or reactive) lymphadenopathy. The diagnostic sensitivity, specificity, positive and negative predictive value, and overall accuracy were 95.3, 100, 100, 72.7 and 95.8%, respectively. While EUS-FNA of metastatic nodes identified the origin in the majority of cases, the procedure resulted in a different histopathological diagnosis from the previous image-based diagnosis in 9 patients. Consequently, 2 patients with testicular cancer were administered bleomycin, etoposide, and cisplatin. An individual with GIST was administered imatinib, and a patient with prostate cancer was administered degarelix (antihormon drug). A total of 5 other patients received palliative medicine due to the change in diagnosis. EUS-FNA also helped determine the appropriate cancer management plan in other patients; specifically, based on the cytology of the metastatic lymph node, EUS-FNA helped determine the cancer stage, and to identify recurrence or the primary cancer from which tissue could not be collected. No EUS-FNA-associated symptoms were reported. To conclude, the present study suggested that EUS-FNA of suspected metastatic lymph nodes appears safe and useful for cancer staging and diagnosing recurrence. It may also useful for diagnosing patients whose collection of samples from the original cancer appeared impractical. EUS-FNA for lymphadenopathy that may not be diagnosed with imaging alone may assist in diagnosis and help to determine the appropriate management strategy.

Esophageal Endosonography for the Diagnosis of Intrapulmonary Tumors: A Systematic Review and Meta-Analysis

BACKGROUND

Biopsy-based diagnosis in patients with paraesophageal intrapulmonary tumors suspected of lung cancer is crucial for adequate treatment planning.

OBJECTIVE

To evaluate the performance of transesophageal endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in the diagnosis of intrapulmonary tumors located near or adjacent to the esophagus.

METHODS

We performed a systematic review (PROSPERO, CRD42016033737) and searched MEDLINE, Embase, BIOSIS Previews, and Web of Science on September 22, 2016, without date or language restrictions. We included studies that evaluated the yield and/or sensitivity of EUS-FNA for diagnosing intrapulmonary tumors. Yield was defined as the number of patients in whom EUS-FNA made a biopsy-proven diagnosis (malignant or nonmalignant) relative to the total number of patients on whom EUS-FNA was performed. Sensitivity was defined as the number of patients in whom EUS-FNA made a biopsy-proven diagnosis of malignancy relative to the total number of patients in whom the tumor was found to be malignant. We performed a random-effects meta-analysis.

RESULTS

Of 3,320 search results, 11 studies were included. Ten had a high risk of bias. The total number of patients was 313; the proportion of patients with malignancy ranged from 87 to 100% across these studies. The average yield was 0.90 (95% CI 0.82-0.95) and the average sensitivity was 0.92 (0.83-0.96). In the subgroup of prospective studies (n = 3), the average yield was 0.80 (0.56-0.93) and the average sensitivity was 0.83 (0.58-0.95). EUS-FNA-induced complications were reported for 5/256 patients (2.0%) for whom this information was available.

CONCLUSIONS

Although the number of high-quality studies is limited, these findings suggest that EUS-FNA is safe and has a high yield for diagnosing intrapulmonary tumors.

Role of endoscopic ultrasound-guided fine needle aspiration in the diagnosis of mass lesions

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an accurate technique for sampling the pancreas and mediastinum; however, limited data are available for other mass lesions. The aim of this study was to explore the value of EUS-FNA in the differential diagnosis of all mass lesions. Data from patients who underwent EUS-FNA for the diagnosis of mass lesions, including pancreatic, mediastinal, celiac and retroperitoneal lesions were retrospectively analyzed. The accuracy was calculated by comparing the results of FNA with the results of pathological examination or follow-up surveillances in non-operated cases. A total of 150 cases were included. The location of the mass varied from the pancreas (n=62) to the mediastinum (n=29), gastrointestinal tract (n=36), celiac cavity and retroperitoneum (n=23). The sensitivity and Youdens index of EUS-FNA in the diagnosis of all lesions were 92.97% and 0.93 respectively. The accuracy of diagnosis of pancreatic, mediastinal, gastrointestinal, celiac and retroperitoneal lesions was 85.48, 89.66, 83.33 and 78.23%, respectively. Masses were categorized into parenchymal organs (n=66), luminal organs (n=36) and enlarged lymph nodes (n=33). Lesions in parenchymal organs were likely to be bigger than those in luminal organs (P=0.03) and enlarged lymph nodes (P=0.01). For solid and cystic masses, which constituted 63.3 and 14.7% of the total masses, no significant difference in diagnostic accuracy was observed (P=0.56); however, lesion sizes were significantly different between these two groups (P=0.04) and the majority of cystic masses were identified in women (P=0.03). Malignant lesions were more common in older (P=0.01) and male (P=0.03) patients. In conclusion, EUS-FNA is an effective tool in the diagnosis of unexplained mass lesions; it influences the management of patients by enabling the appropriate treatment to be identified.

Esophageal wall rupture after EUS-FNA for mediastinal staging: report of two cases

Esophageal wall rupture after EUS-FNA for mediastinal staging is a severe complication. Here we describe the management of two patients with esophageal wall rupture and the presence of empyema. Management was in both cases surgical and consisted of a decortication via thoracotomy. Postoperative IV antibiotics and parenteral nutrition were continued until the first negative X-ray with gastrografin. Both patients recovered and left the hospital in good condition and with oral intake.

Can endoscopic ultrasound distinguish between mediastinal benign lymph nodes and those involved by sarcoidosis, lymphoma, or metastasis?

BACKGROUND

Lymph nodes (LNs) echofeatures on endoscopic ultrasound (EUS) and concurrent fine needle aspiration (FNA) are alternatives to highly invasive approaches for etiologic diagnosis of mediastinal lymphadenopathy (MLAD).

AIMS

To evaluate the efficacy of LNs echofeatures and FNA via EUS to distinguish benign LNs from LNs involved by sarcoidosis, lymphoma, and metastasis in non-lung cancer patients.

METHODS

A retrospective review of patients who underwent EUS-FNA for MLAD was performed. Echofeatures of LNs including echogenicity, margins, shape, and LN size were recorded. Final diagnosis was made based on surgical sampling or clinical diagnosis with long-term follow-up. Only patients diagnosed as benign MLAD, sarcoidosis, lymphoma, and metastasis included. Diagnostic value of echofeatures and FNA was evaluated.

RESULTS

Included were 162 patients with final diagnosis of benign (68), sarcoidosis (33), lymphoma (20), and metastasis (41). The median LN along axis in the benign group [20.5 mm (6-76)] was significantly shorter than in the metastasis [28 mm (9-82)] and sarcoidosis [27 mm (17-50)] groups (p < 0.05). The median LN short axis in the benign group [11 mm (2-50)] was significantly shorter than in the metastasis [17 mm (5-44)] and lymphoma [16 mm (7-47)] groups (p < 0.05). No other echofeatures showed a discriminant value among the groups. When performing FNA, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EUS-FNA were 73.7, 100, 100, 72.2, and 84.4 %, respectively.

CONCLUSION

Although benign MLAD tend to be smaller than other etiologies, echofeatures of LNs are not reliable etiologic diagnostic approach to MLAD. Therefore, FNA is suggested when feasible. However, due to relatively low sensitivity, LNs with benign FNA results should be subjected to further work-up if they are clinically suspicious.

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 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.