Endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy in the diagnosis of mediastinal lesions: safety, feasibility and diagnostic yield – experience in 50 cases

Abstract

BackgroundEndobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) is the technique of choice in the study of mediastinal and hilar lesions; however, it can be affected by the insufficiency of intact biopsy samples, which might decrease its diagnostic yield for certain conditions, thus requiring re-biopsies or additional diagnostic procedures such as mediastinoscopy when probability of malignancy remains high.ObjectivesOur objectives were to 1) attempt to reproduce this technique in the same conditions that we performed EBUS-TBNA, that is, in the bronchoscopy suite and under moderate sedation; 2) describe the method used for its execution; 3) determine its feasibility by accessing different lymph node stations applying our method; 4) analyze the diagnostic yield and its complications.MethodsProspective study of 50 patients who underwent EBUS-TBNA and EBUS-guided TMC in a single procedure using a 22-G TBNA needle and a 1.1 mm cryo-probe subsequently between January and August 2022. Patients with mediastinal lesions greater than 1 cm were recruited and EBUS-TBNA and TMC were performed in the same lymph node station.ResultsThe diagnostic yield was 82% and 96% for TBNA and transbronchial mediastinal cryobiopsy, respectively. Diagnostic yields were similar for sarcoidosis, while cryobiopsy was more sensitive than TBNA in lymphomas and metastatic lymph nodes. As for complications, there was no pneumothorax and in no case was there significant bleeding. There were no complications during the procedure or in the follow-up of these patients.ConclusionsTMC following our method is a minimally invasive, rapid, and safe technique that can be performed in a bronchoscopy suite under moderate sedation, with a higher diagnostic yield than EBUS-TBNA, especially in cases of lymphoproliferative disorders and mestastatic lymph nodes, or when more biopsy sample is needed for molecular determinations.

Endobronchial ultrasound‐guided cryobiopsy for diagnosing a case of granulomatosis with polyangiitis

“…This is mainly because of the need to obtain larger tissue samples for histological and molecular analysis. Several studies in the recent literature have already demonstrated the superiority of EBUS guided cryobiopsy over EBUS‐TBNA in terms of diagnostic yield for benign and lymphoproliferative diseases, with significantly low complication rate 2–5 . The most common adverse event is minor airway bleeding with no need for intervention, while the reported incidence of grade 3–4 bleeding is 2% 2,3 .…”

“…Several studies in the recent literature have already demonstrated the superiority of EBUS guided cryobiopsy over EBUS‐TBNA in terms of diagnostic yield for benign and lymphoproliferative diseases, with significantly low complication rate. 2 , 3 , 4 , 5 The most common adverse event is minor airway bleeding with no need for intervention, while the reported incidence of grade 3–4 bleeding is 2%. 2 , 3 Therefore, in the case we presented, this technique appeared particularly indicated for several reasons such as: the central location of the consolidations, the visibility of the target on endobronchial ultrasound, the inconclusive ROSE, and the absence of vascular structures that could make the biopsy dangerous.…”

Endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy: a narrative review

“…Ariza-Prota et al ( 11 ) conducted a prospective study in Spain on 50 patients, wherein participants underwent EBUS-TBNA followed by EBUS-TMC. Maturu et al ( 12 ) carried out a prospective study on 46 patients in India, in which EBUS-TMC was conducted if rapid on-site evaluation (ROSE) during EBUS-TBNA yielded insufficient or inconclusive results.…”

What is new in mediastinal staging?

“…Endobronchial ultrasound-guided transbronchial lymph node cryobiopsy (EBUS-TBLCB) involves a similar technique as EBUS-IFB where a hole is first created in the airway for advancement of the cryoprobe. Multiple tools have been reported for this purpose, including needles with various gauges, electrocautery knife and Nd YAG Laser [60 ▪ ,61 ▪▪ ,62,63,64 ▪▪ ,65]. After freezing, the cryoprobe and EBUS scope are removed in block for specimen retrieval (Fig.…”

“…Procedure time is longer when cryobiopsy is added to TBNA but is well tolerated by patients even when receiving moderate sedation. Reported complications are rare and include bleeding, pneumothorax, and pneumomediastinum, infrequently requiring intervention outside of the bronchoscopy procedure [60 ▪ ,61 ▪▪ ,62]. Based on available data, EBUS-TBLCB may be superior to EBUS-TBNA in the diagnosis of rare thoracic malignancies and nonmalignant conditions, but the role in the diagnosis of typical lung cancers appears more complementary.…”