Supplementary Material for: Feasibility and safety of transesophageal mediastinal cryobiopsy in the diagnosis of mediastinal pathologies

Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) remains the gold standard for the diagnosis of mediastinal pathologies. Its greatest limitation has been the low diagnostic yield in lymphoproliferative disorders as well as insufficient samples for molecular testing. Transesophageal examinations using an EBUS-scope (EUS-B) have helped increase the diagnostic yield by allowing for additional biopsies of paraesophageal and intraabdominal lesions. Similarly, the novel approach of transbronchial mediastinal cryobiopsy has further increased the yield by providing larger and better-preserved biopsies. Both complimentary techniques have shown great individual feasibility and safety. However, the feasibility of transesophageal cryobiopsies in the evaluation of mediastinal pathologies remains a subject of debate. Aim: To investigate the safety and feasibility of transesophageal EBUS-guided mediastinal cryobiopsies performed at our centre. Method: We conducted a retrospective review of 30 patients who underwent mediastinal cryobiopsy through the esophagus at our institution between October 2023 and March 2024. Data on patient demographics, diagnostic yield and complications were collected and analysed. Results: The mean patient age was 43 years, with a gender distribution of 60% male and 40% female. The primary indications included suspicion of lymphoproliferative disorders, suspected sarcoidosis, and malignancies with paraesophageal lesions. The overall diagnostic yield was 93%. No major complications were noted in any of the patients. Conclusion: Transesophageal mediastinal cryobiopsy appears to be a promising complimentary technique for mediastinal evaluation with a relatively high diagnostic yield and favourable safety profile. However, further studies with larger cohorts are warranted to validate the findings at our institution