Endoscopic ultrasound-guided fine-needle aspiration and cytology for differentiating benign from malignant lymph nodes

Current perspectives on the diversification of endoscopic ultrasound-guided fine-needle aspiration and biopsy

Endoscopic ultrasound-guided tissue acquisition (EUS-TA) has undergone significant advancements since it was first reported in 1992. Initially focused on the pancreas, EUS-guided fine-needle aspiration (FNA) has now been extended to encompass all organs proximal to the gastrointestinal system. Recently, a novel fine-needle biopsy (FNB) needle with an end-cut tip was developed, allowing for the collection of specimens suitable for histological assessment, a feat hard to achieve with traditional needles. The FNB needle holds promise for applications in immunohistochemistry staining and genetics evaluation, and it has the potential to yield specimens of comparable quality to core needle biopsy during percutaneous puncture, especially for lesions beyond the pancreas, such as lymph nodes. This review focuses on the efficacy of EUS-FNA/FNB for extended target regions, specifically lymph nodes, spleen, adrenal gland, and ascites. The indications for EUS-FNA have greatly expanded beyond the pancreas over the years, and future improvements and innovations in puncture needles will allow for the collection of higher-quality specimens, which is expected to play a significant part in personalized cancer treatment.

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.

High Diagnostic Accuracy and Safety of Endoscopic Ultrasound-Guided Fine-Needle Aspiration in Malignant Lymph Nodes: A Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is increasingly being used for diagnosing lymphadenopathy. We aim to systematically review the accuracy of EUS-FNA in differentiating benign and malignant mediastinal and abdominal lymph nodes (LNs).

METHODS

A comprehensive literature search was performed on multiple electronic databases through February 2020. A random or fixed effect model generated the pooled sensitivity, specificity, likelihood ratio (LR), and diagnostic odds ratio (DOR) of EUS-FNA. Subgroup analyses and meta-regression were used to explore sources of heterogeneity.

RESULTS

Twenty-six studies involving 2753 patients with 2833 LNs were included. In the differential diagnosis of benign and malignant LNs, EUS-FNA had a pooled sensitivity, specificity, positive LR, and negative LR of 87% (95% confidence interval [CI] 86-90%), 100% (95% CI 99-100%), 68.98 (95% CI 42.10-113.02), and 0.14 (95% CI 0.11-0.17), respectively. The pooled rate of adverse events associated with EUS-FNA was 1.57% (95% CI 1.06-2.24%). The summary receiver operating characteristic (SROC) yielded an area under the curve (AUC) of 0.9912. EUS-FNA performed in mediastinal LNs gained a sensitivity of 85% (95% CI 81-88%), while in abdominal LNs, it reached 87% (95% CI 82-91%). The sensitivity of the subgroup with rapid on-site evaluation (ROSE) was 91% (95% CI 89-93%), while non-ROSE was 85% (95% CI 82-87%).

CONCLUSIONS

EUS-FNA is a sensitive, highly specific, and safe method for distinguishing benign and malignant mediastinal or abdominal LNs. However, the sensitivity of EUS-FNA still varies significantly among different centers.

Application Value of Ultrasound-Guided Fine Needle Aspiration Cytological Examination and Ultrasound Evaluation

In this paper, chronic inflammatory cell infiltration was seen during this period. The reason for the false-positive result may be the atypical proliferation of cells caused by chronic inflammatory stimulation with malignant cytology. 12 cases of false negative results, including 2 cases of type I nodules, 10 cases of type III nodules, postoperative histology and pathology were papillary carcinoma, there are many reasons for false negative results, including the size of the nodules, the puncture operator, the technical level, internal tissue composition and properties of the nodules all affect the accuracy of puncture and cytopathology results. The satisfaction of puncture specimens of each group was calculated and compared. For thyroid nodules with the maximum diameter ≤5 mm, the satisfaction rate of puncture specimens was 87.2%, and the diagnostic sensitivity and accuracy of ultras guided fine needle aspiration biopsy were relatively low. Cytological results were in poor agreement with postoperative histological and pathological results, so it was recommended to take active follow-up for thyroid nodules with the maximum diameter ≤5 mm to reduce unnecessary puncture. The overall puncture success rate is relatively high, ≤10 mm low-echo nodules or even ≤5 mm nodules can be cytological puncture, especially the kind of close to the capsule, trachea and recurrent laryngeal nerve nodules, for the largest diameter of >5 mm, the satisfaction rate of puncture specimens is relatively high is 93.2%. Moreover, the sensitivity and accuracy of ultrasound guided fine needle aspiration biopsy were relatively high, and the cytological results were in good agreement with the postoperative histological and pathological results. Therefore, it was feasible to confirm the diagnosis of suspected malignant nodules by ultrasound. The diagnostic in each group and the consistency between cytological diagnosis and histological diagnosis were analyzed by comparing the histological and pathological results after surgery. Ultrasound-guided fine needle aspiration biopsy can be used more effectively in clinical practice.

Interobserver Reliability of Endoscopic Ultrasonography: Literature Review

Endoscopic ultrasonography (EUS) has been applied to the diagnosis of various digestive disorders. Although it has been widely accepted and its diagnostic value is high, the dependence of EUS diagnosis on image interpretation done by the endosonographer has persisted as an important difficulty. Consequently, high interobserver reliability (IOR) in EUS diagnosis is important to demonstrate the reliability of EUS diagnosis. We reviewed the literature on the IOR of EUS diagnosis for various diseases such as chronic pancreatitis, pancreatic solid/cystic mass, lymphadenopathy, and gastrointestinal and subepithelial lesions. The IOR of EUS diagnosis differs depending on the disease; moreover, EUS findings with high IOR and those with IOR that was not necessarily high were used as diagnostic criteria. Therefore, to further increase the value of EUS diagnosis, EUS diagnostic criteria with high diagnostic characteristics based on EUS findings with high IOR must be established.

Endoscopic ultrasound-guided-fine-needle aspiration/fine-needle biopsy in diagnosis of mediastinal lymphadenopathy - A boon

Background/Objectives:

Evaluation of mediastinal lymphadenopathy (MLA) is a great diagnostic challenge considering the myriad of causes. In recent years, the role of endoscopic ultrasound (EUS) has been greatly extended in evaluation of MLA due to its safety, reliability, and accuracy. The present study details the role of EUS-guided-fine-needle aspiration/fine-needle biopsy (EUS-FNA/FNB) in MLA of unknown origin.

Methods:

Seventy-two patients (34 men) with MLA of unknown etiology were studied. Mediastinum was evaluated with linear echoendoscope and FNA/FNB was performed with 22-G needle and sent for cytology, histopathological, and mycobacterial growth indicator tube/GeneXpert evaluation. EUS-FNA/FNB diagnosis was based on cytology reporting by pathologists. Patients tolerated the procedure, and insertion of needle into the lesion was always successful without any complications.

Results:

EUS-FNA/FNB established a tissue diagnosis in 66/72 patients in first sitting, while six patients underwent repeat procedure. EUS-FNA diagnoses (after second sitting) were tuberculous lymphadenitis in 45/72 (62.5%), metastatic lymph nodes 12/72 (16.7%), reactive lymphadenopathy 6/72 (8.3%), sarcoidosis 4/72 (5.6%), and lymphoma 2/72 (2.8%), while it was nondiagnostic in 3/72 (4.1%) patients. Final diagnosis was based on combined clinical presentation, EUS-FNA/FNB result and clinicoradiological response to treatment on long-term follow-up of 6 months.

Conclusion:

EUS echo features along with EUS-FNA/FNB can diagnose MLA and surgical biopsy can be avoided.

New endoscopic ultrasonography criteria for malignant lymphadenopathy based on inter-rater agreement.PLoS One. 2019;14:e0212427. [PMID: 30794598 DOI: 10.1371/journal.pone.0212427]

Background and aims

Various studies have been previously conducted on the diagnosis of lymphadenopathy as benign or malignant, but the results vary. These studies did not describe the inter-rater agreement on the EUS features of lymphadenopathy. In this study, we evaluate the inter-rater agreement on EUS features and propose EUS diagnostic norms for lymphadenopathy based on inter-rater agreement.

Method

A total of 68 lymph nodes subjected to EUS-fine needle aspiration (FNA) were reviewed by five endoscopic experts. The EUS features evaluated lymph node size, shape, border, margin, echogenicity, homogeneity, and the hilum of the lymph node. Inter-rater agreement (multi-rater kappa statics) was performed. We established new criteria using results with a high degree of inter-rater agreement from EUS features and compared them with the former criteria.

Result

There was a moderate agreement on shape, kappa (K) = 0.44 (95% confidence interval [CI]: 0.34–0.54), and fair agreement on echogenicity, homogeneity, border, and hilum of the lymph node, K (95% CI) = 0.33 (0.17–0.38), 0.34 (0.26–0.35), 0.22 (0.21–0.31), and 0.22 (0.11–0.26), respectively. This resulted in the establishment of new EUS diagnostic criteria using shape, long axis > 20 mm and short axis > 10 mm. New criteria were superior to old criteria (area under the curve 0.82 vs 0.52, P < 0.001).

Conclusion

EUS diagnostic criteria for lymphadenopathy based on inter-rater agreement were more accurate than old criteria. This result will be useful for the diagnosis of lymphadenopathy.