Mediastinal "deep freeze"-transcarinal lymph node cryobiopsy

Utility and safety of endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-TMC): A systematic review and meta-analysis

BACKGROUND

Modalities to improve tissue acquisition during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) have been investigated. Endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-TMC) is a modality to obtain larger histological samples by inserting a cryoprobe into the mediastinal lesion. We aimed to study the diagnostic yield and safety of EBUS-TMC.

METHODS

We performed a systematic search of the PubMed and Embase databases to extract the relevant studies. We then performed a meta-analysis to calculate the diagnostic yield of EBUS-TMC and compare it with EBUS-TBNA.

RESULTS

Following a systematic search, we identified 14 relevant studies (869 patients undergoing EBUS-TMC and EBUS-TBNA). We then performed a meta-analysis of the diagnostic yield of EBUS-TMC and EBUS-TBNA from studies wherein both procedures were performed. The pooled diagnostic yield of EBUS-TMC was 92% (95% confidence interval [CI], 89%-95%). The pooled diagnostic yield of EBUS-TBNA was 81% (95% CI, 77%-85%). The risk difference in yield was 11% (95% CI, 6%-15%, I2 = 0%) when EBUS-TMC and EBUS-TBNA were compared. The only complication reported commonly with EBUS-TMC was minor bleeding. The complication rate was comparable with EBUS-TBNA.

CONCLUSION

EBUS-TMC provides a greater diagnostic yield with a similar risk of adverse events compared to EBUS-TBNA. Future studies are required to clearly establish which patients are most likely to benefit from this modality.

[EBUS-guided cryobiopsy in the diagnosis of mediastinal lesions - step by step]

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the gold standard in the diagnosis of mediastinal and hilar lesions. For certain purposes, such as the diagnosis and subtyping of lymphoproliferative disorders or molecular pathology, a larger amount of intact sample material is required. EBUS cryobiopsy is a new and efficient tool for this purpose. As it is a new approach, there is still no standardised workflow. In this review, we present the procedure step by step as it is performed at the Ruhrlandklinik in Essen.

Endobronchial Ultrasound-Guided Transbronchial Mediastinal Cryobiopsy versus Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration for Mediastinal Disorders: A Meta-Analysis

INTRODUCTION

Endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-TMC), a novel technique, has been reported to improve the diagnostic value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal lesions in recent studies. Current literature suggests that this procedure has greater diagnostic efficacy compared to conventional EBUS-TBNA. This systematic review and meta-analysis aimed to evaluate the diagnostic yield and complications associated with EBUS-TMC in comparison to EBUS-TBNA, thereby exploring the potential of this novel technique in enhancing the diagnostic utility for mediastinal lesions.

METHODS

A comprehensive literature review was conducted by searching the PubMed, Embase, and Google Scholar databases for articles published from inception to December 31, 2023. The objective of this review was to evaluate the utilization of EBUS-TMC in diagnosing mediastinal disease, while also assessing the quality of each study using the QUADAS-2 tool. The diagnostic yield estimates were subjected to a meta-analysis utilizing inverse variance weighting. Furthermore, a comprehensive analysis of the complications associated with this procedure was performed.

RESULTS

The meta-analysis included 10 studies involving a total of 538 patients. The findings of the meta-analysis demonstrated that EBUS-TMC yielded an overall diagnostic rate of 89.59% (482/538), while EBUS-TBNA yielded a rate of 77.13% (415/538). The calculated inverse variance-weighted odds ratio was 2.63 (95% confidence interval, 1.86-3.72; p < 0.0001), and I2 value was 11%, indicating a statistically significant difference between the two techniques. The associated complications consisted of pneumothorax, pneumomediastinum, mediastinitis, and bleeding, with an incidence of 0.74% (4/538), 0.37% (2/538), 0.0% (0/538), and 1.12% (6/538), respectively. Moreover, the funnel plot displayed no discernible publication bias. Further subgroup analysis revealed a notable improvement in the diagnosis value for lymphoma (86.36% vs. 27.27%, p = 0.0006) and benign disorder (87.62% vs. 60.00%, p < 0.0001).

CONCLUSION

This review of the current available studies indicated that EBUS-TMC enhanced overall diagnostic yields compared to EBUS-TBNA, particularly for diagnosing benign disease and lymphoma. This procedure was not associated with any serious complications.

The utility of endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-TBMC) for the diagnosis of mediastinal lymphoma

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a revolutionary tool for the diagnosis and staging of mediastinal disorders. Nevertheless, its diagnostic capability is reduced in certain disorders such as lymphoproliferative diseases. EBUS-guided transbronchial mediastinal cryobiopsy (EBUS-TBMC) is a novel technique that can provide larger samples with preserved tissue architecture, with an acceptable safety profile. In this case report, we present a middle-aged gentleman with a huge anterior mediastinal mass and bilateral mediastinal and hilar lymphadenopathy. He underwent EBUS-TBNA with rapid on-site evaluation (ROSE) followed by EBUS-TBMC, all under general anaesthesia. Histopathological analysis showed discordance between EBUS-TBNA and EBUS-TBMC in which only TBMC samples provided adequate tissue to attain a diagnosis of primary mediastinal large B-cell lymphoma. This case report reinforced the diagnostic role of EBUS-TBMC in the diagnosis of lymphoproliferative diseases.

Endobronchial Ultrasound-guided Mediastinal Lymph Nodal Cryobiopsy in Patients With Nondiagnostic/Inadequate Rapid On-site Evaluation: A New Step in the Diagnostic Algorithm

BACKGROUND

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is considered the investigation of choice for sampling mediastinal nodes. A major drawback of EBUS-TBNA is its lower diagnostic yield for lymphoma and benign diseases. EBUS-guided mediastinal cryobiopsy (EBUS-MCB) is a novel technique that provides larger nodal biopsy samples, with an acceptable safety profile. In this study, we aimed to evaluate the diagnostic yield of EBUS-MCB in patients with an inconclusive rapid on-site evaluation (ROSE).

METHODS

This is a prospective study of patients who underwent EBUS-TBNA for undiagnosed mediastinal lymphadenopathy. Patients in whom ROSE did not yield a diagnosis (nondiagnostic ROSE) or ROSE revealed scanty atypical cells (inadequate ROSE) were subjected to EBUS-MCB. The diagnostic yield, adequacy, and complications of EBUS-MCB were analyzed.

RESULTS

Of the 196 patients undergoing EBUS-TBNA, 46 patients underwent EBUS-MCB. Thirty-two cases underwent EBUS-MCB for a nondiagnostic ROSE. EBUS-MCB confirmed the diagnosis in 19/32 (59.3%) cases. The additive diagnostic yield of EBUS-MCB over EBUS-TBNA was 43.7% (14/32 cases). In all 14 cases where EBUS-MCB was performed for an inadequate ROSE, the material obtained by EBUS-MCB was adequate for ancillary studies. The most common complication observed was a minor bleed in 13 cases.

CONCLUSION

EBUS-MCB has a diagnostic yield of 59.3% when performed in cases with a nondiagnostic EBUS-ROSE. The tissue obtained by EBUS-MCB is adequate for ancillary studies. We propose EBUS-MCB as an additional diagnostic step in cases with an inconclusive ROSE while performing EBUS-TBNA. Larger studies are, however, needed before EBUS-MCB can be incorporated in the diagnostic algorithm for the evaluation of mediastinal lesions.

What is new in mediastinal staging?

PURPOSE OF REVIEW

Appropriate staging is of utmost importance in nonsmall cell lung cancer (NSCLC), as the pathologic stage dictates both overall prognosis and appropriate therapeutic pathways. This article seeks to review the current recommendations for mediastinal staging of NSCLC and available modalities to achieve this. Landmark publications pertaining to recent advancements in NSCLC treatments are also highlighted and the role of specific bronchoscopic modalities for tissue acquisition are reviewed.

RECENT FINDINGS

Recent advancements in the treatment of NSCLC have made accurate mediastinal staging more important than ever. Guidelines and recommendations outlining patients that warrant invasive mediastinal staging are available and a systematic approach should be utilized when sampling is performed. Ensuring the adequacy of tissue for the growing number of molecular biomarkers that must be tested has been the focus of many recent studies.

SUMMARY

Appropriate mediastinal staging is crucial for the management of patients with NSCLC as is obtaining adequate tissue for diagnostic and therapeutic purposes. EBUS-TBNA is sufficient for the diagnosis of nonsmall cell and small cell lung carcinomas, but EBUS-guided intranodal forceps and cryobiopsy may provide more optimal specimen for patients with benign disease, such as sarcoidosis, or in cases of lymphoma. Further studies are necessary to better delineate the role of these techniques in the diagnosis and staging of mediastinal diseases before they become the primary diagnostic modalities.

Endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy: a narrative review

Background and Objective

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive, safe, and well-established method for diagnosing and staging lung cancer and other conditions associated with mediastinal lymphadenopathy. Efforts have been made to enhance the material adequacy of EBUS-TBNA, including the recent introduction of EBUS-guided transbronchial mediastinal cryobiopsy (EBUS-TMC). This advancement facilitates the acquisition of larger and better-preserved tissue samples from the mediastinum. We evaluated the diagnostic accuracy and safety of EBUS-TMC in the diagnosis of malignant lesions and its effectiveness in relation to benign conditions, such as tuberculosis and sarcoidosis.

Methods

We searched the PubMed® database for relevant English articles published up to July 1, 2023. Subsequently, we conducted a comprehensive bibliographic analysis with a particular emphasis on diagnostic yield, safety profile, and procedural technicalities.

Key Content and Findings

Our narrative review, comprising seven publications, emphasizes the significance of EBUS-TMC as an effective technique for obtaining diagnostic tissue in malignant and benign conditions while maintaining an excellent safety profile. Furthermore, its capability for obtaining larger tissue samples facilitates molecular and immunological analysis in non-small cell lung cancer.

Conclusions

EBUS-TMC exhibits significant efficacy with regard to obtaining diagnostic tissue in malignant and benign conditions. However, further studies are needed to evaluate uncertainties regarding the selection of suitable cases and technical intricacies.

Is the diagnostic yield of mediastinal lymph node cryobiopsy (cryoEBUS) better for diagnosing mediastinal node involvement compared to endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)? A systematic review

INTRODUCTION

New tools such as cryobiopsy of mediastinal lymph nodes (cryoEBUS) have been described to improve the diagnostic usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). The literature suggests that this novel procedure could be associated with greater diagnostic usefulness than conventional EBUS-TBNA.

METHODS

To develop a systematic analysis and meta-analysis on the diagnostic diagnostic yield and safety of cryobiopsy of hilar and mediastinal adenopathies compared to EBUS-TBNA.

RESULTS

Seven studies that had included a total of 555 patients were considered in this review, with 365 (65.7%) of these patients having an etiology of malignant lymph node involvement. The overall diagnostic usefulness of cryoEBUS was higher compared to EBUS-TBNA (92% vs. 80%). However, when the results were analysed according to the specific aetiologies of the adenopathies, cryoEBUS was especially useful in cases of lymphomas or non-pulmonary carcinomas (83% vs. 42%) and in cases that were benign (87% vs. 60.1%), with no significant differences being found in specific cases of lung cancer. For lymphoma, cryoEBUS was diagnostic in 87% of cases compared to 12% for EBUS-TBNA and in addition, also allowed the characterisation of every lymphoma subtype. Genetic studies and immunohistochemical determination of PD-L1 was possible in almost all (97%) of the samples obtained by cryoEBUS, while this was only possible in 79% of those obtained by EBUS-TBNA. The most frequent complication was light bleeding, which was described in up to 85% of cases in some series.

CONCLUSION

CryoEBUS could represent a promising technique in the diagnostic algorithm used for mediastinal and hilar involvement. Although cryoEBUS did not significantly improve the diagnosis of lung cancer compared to EBUS-TBNA, the results were significantly better in patients with benign pathologies and other tumour types, including lymphomas. In addition, it seems that the samples obtained by cryoEBUS better defined the histological subtypes of lymphoma and allowed complete molecular characterisation in cases of lung cancer. The technique has proven to be safe and no serious complications were described after the procedure.

Only EBUS-Guided Mediastinal Lymph Node Cryobiopsy Enabled Immunotherapy in a Patient with Non-Small Cell Lung Cancer

Personalized treatment of metastatic non-squamous non-small cell lung cancer (NSCLC) requires detailed molecular characterization of the tumour including detection of predictive driver mutations and programmed death ligand 1 (PD-L1) expression. Complete detection is influenced by the amount of tumour cells sampled as well as their quality. Different sampling techniques may be necessary to provide sufficient tumour material for comprehensive molecular characterization. Missing the detection of targetable molecular genetic aberrations would have a serious impact on the quality of life and prognosis of a patient. This case report highlights the importance of biopsy technique in a patient with NSCLC. Several procedures—pleural puncture, transthoracic lung biopsy and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA)—could not provide sufficient tumour material for precise tumour characterization. Only the addition of EBUS-guided transbronchial lymph node cryobiopsy (EBUS-TBLNC) enabled complete immunohistochemical and genetic tumour characterization, demonstrating PD-L1 expression in 100% of the tumour cells in the absence of actionable genetic alterations. Based on these results, immunotherapy was initiated.

Thoracic SMARCA4-deficient undifferentiated tumor diagnosed by transbronchial mediastinal cryobiopsy: A case report

Thoracic SMARCA4-deficient undifferentiated tumors (SMARCA4-UT) have a poor prognosis and are often diagnosed at an inoperable advanced stage. Herein, we report a case of SMARCA4-UT diagnosed by endobronchial ultrasound-guided transbronchial cryobiopsy (EBUS-cryo). The patient was a 42-year-old man with a history of smoking. Chest computed tomography revealed a right upper lobe nodule and an enlarged #11s lymph node. Core tissues could not be obtained by EBUS-guided transbronchial needle aspiration (EBUS-TBNA) for diagnosis and mediastinal staging; hence, EBUS-guided intranodal forceps biopsy (EBUS-IFB) was performed. However, a detailed diagnosis beyond poorly differentiated carcinoma could not be obtained. Subsequent EBUS-cryo provided sufficient specimens for immunohistochemical and molecular evaluation and SMARCA4-UT was definitively diagnosed. Thus, EBUS-cryo could be of additional diagnostic value for uncommon tumors, such as SMARCA4-UT, conjointly with EBUS-IFB as well as EBUS-TBNA.

[Transbronchial cryobiopsy for mediastinal lesions: a pilot study]

OBJECTIVE

To describe a novel transbronchial cryobiopsy technique for mediastinal lesions after initial ultrasound assessment and EBUS-TBNA.

MATERIAL AND METHODS

Transbronchial cryobiopsy (TBCB) was performed in 35 patients with suspicious mediastinal lesions between November 2020 and September 2022. Age of patients ranged from 22 to 75 years (median 50 [39; 62]). Men-to-women ratio was 13:22.

RESULTS

According to morphological data, patients with sarcoidosis (n=13), NSCLC (n=7) and metastases of other tumors (n=3) prevailed. There were patients with B-cell lymphoma (n=1), Castleman disease (n=1) and small cell lung cancer (n=2). Among 15 biopsies for immunohistochemical examination, samples were sufficient for final morphological conclusion in 11 (73.3%) cases (95% CI 48.5-89.1). In 4 (11.4%) cases (95% CI 4.5-26), examination was uninformative. Repeated biopsy was performed in 2 cases, and sarcoidosis of thoracic lymph nodes was confirmed. Sensitivity, specificity and accuracy of transbronchial cryobiopsy were 93.3, 100 and 94%, respectively. There were no clinically significant complications. In one case, chest X-ray revealed pneumomediastinum without need for additional treatment.

CONCLUSION

Transbronchial mediastinal cryobiopsy is a perspective method for diagnosis of mediastinal neoplasms. Apparently, this approach may be advisable in patients with suspected sarcoidosis or lymphoproliferative diseases.

Esophageal submucosal tumor diagnosed with EBUS-guided transbronchial mediastinal cryobiopsy: A case report

Cryobiopsy is advantageous for collecting larger specimens with minimum crushing compared to forceps biopsy and transbronchial needle aspiration (TBNA), but it has not been widely used for mediastinal tumors. In this report, a leiomyoma of the thoracic esophagus was diagnosed with endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-cryo). An asymptomatic 49-year-old woman had a 2.6-cm sized submucosal tumor (SMT) of the esophagus adjacent to the trachea and left main bronchus. EBUS-TBNA and EBUS-guided intranodal forceps biopsy were performed, followed by EBUS-cryo. The biopsy forceps could not be inserted into the tumor, but the cryoprobe was smoothly inserted. EBUS-TBNA could not obtain enough spindle-shaped tumor cells for immunohistochemical staining, but EBUS-cryo provided sufficient specimens for diagnosing the leiomyoma. Adding EBUS-cryo to EBUS-TBNA has recently been reported to achieve high diagnostic yields for lymphomas, uncommon tumors, and benign diseases. EBUS-cryo seems a valid diagnostic option for esophageal SMTs that are difficult to diagnose with needles and forceps.

Airway stenosis complicated by endobronchial ultrasound-guided tissue acquisition: A case report

Endobronchial ultrasound (EBUS)‐guided tissue acquisition (TA) performed by transbronchial needle aspiration (TBNA) is the main diagnostic procedure in mediastinal and hilar lymph node (LN) biopsy. EBUS‐guided intranodal forceps biopsy (EBUS‐IFB) and EBUS‐guided cryobiopsy can achieve higher diagnostic yield of lymphomas, uncommon tumors, and benign diseases. However, these techniques require the creation of a tract to insert biopsy devices, which may result in critical complications. Here, we report a rare case of airway stenosis (AS) that occurred after EBUS‐TA for mediastinal LN biopsy. An 80‐year‐old man had multiple pulmonary nodules and an enlarged mediastinal LN. EBUS‐TBNA and EBUS‐IFB were performed for histological diagnosis. Cutaneous adnexal carcinoma (CAC) was diagnosed. The patient underwent chemotherapy. Four months later, he was hospitalized for AS due to a tracheal tumor with dyspnea. Chest computed tomography and bronchoscopy revealed that the tracheal tumor was caused by invasion from the biopsied LN into the tracheal lumen by tract seeding (TS) caused by EBUS‐TA. Cryotherapy was performed. The tracheal tumor was pathologically consistent with CAC and is currently under control with radiotherapy. TS‐associated EBUS‐TA is rare but may increase in frequency with aggressive tissue sampling techniques. Bronchoscopists should perform EBUS‐TA with awareness of the potentially serious complications.