🎯 Background & Rationale
Endoscopic ultrasound using a convex EBUS bronchoscope (EUS-B-FNA) has become a vital, minimally invasive modality for staging lung cancer and accessing mediastinal stations, left adrenal glands, and periesophageal lesions beyond the reach of standard EBUS-TBNA. While the technique is considered safe, the direct transesophageal passage of the needle and the use of an angled, lateral-viewing bronchoscope in an anatomically un-fixed organ raise theoretical concerns regarding esophageal mucosal injury. Despite its growing adoption by interventional pulmonologists, no prior study had systematically evaluated the incidence, severity, and clinical implications of procedure-related esophageal mucosal alterations.
👥 Study Design & Population
- Study Type: Prospective observational single-center cohort study.
- Population: 33 adult outpatients undergoing a total of 37 EUS-B-FNA procedures between February and August 2025 for diagnostic evaluation or mediastinal/pulmonary lesion staging.
- Exclusion Criteria: Patients who did not undergo FNA, those with clinical or radiologic suspicion of esophageal pathology, or those unable to tolerate the procedure.
📈 Methodology & Rigor
- Procedural Technique: Procedures were performed by board-certified interventional pulmonologists using convex probe endosonography bronchoscopes. Esophageal insertion was predominantly performed via the nasal route under conscious sedation. 22-gauge needles were used with a median of 3 passes per lesion. Prophylactic antibiotics were selectively administered based on identified risk factors (e.g., necrotic or cystic lesions).
- Mucosal Assessment: Immediately following EUS-B-FNA, the esophageal mucosa was systematically inspected during the same endoscopic session—either via upper endoscopy (performed by a gastroenterologist) or directly using the EBUS scope optics with controlled air insufflation.
- Follow-up & Outcomes: Primary outcomes centered on the endoscopic documentation of mucosal injury classified by type, location, and extent. Patients were prospectively tracked for 1 month via telephone and outpatient reassessment for adverse events, readmissions, or required interventions.
🔬 Key Findings [or Planned Endpoints]
- Mucosal Alterations: Esophageal mucosal changes occurred in 89.2% (33/37) of procedures. The vast majority were minor: punctate lesions (48.6%; median 1 mm) and mucosal edema (29.7%; median 1 mm), alongside minor hemorrhage (5.4%) and erythema (5.4%).
- Severe Complications: No lacerations, ulcerations, erosions, perforations, or strictures were observed. No procedures required interruption.
- Procedure-Related Adverse Events: Two minor immediate events occurred (5.4%): one self-limited episode of vomiting without aspiration and one instance of sonographically detected submucosal edema without clinical sequelae. No readmissions, severe adverse events, or interventions (endoscopic, surgical, or medical) occurred during the 1-month follow-up.
- Diagnostic Performance: Overall sample adequacy was 86.5%, and the diagnostic yield was 59.5%.
⚖️ Critical Appraisal
- Strengths: This is the first prospective study to systematically and rigorously evaluate esophageal mucosal integrity following EUS-B-FNA, addressing a notable gap in interventional pulmonology literature. Standardized post-procedure inspection protocols and 1-month clinical tracking enhance internal validity.
- Limitations: The study is restricted by a small sample size from a single academic center, potentially limiting broader external generalizability. Additionally, all procedures were performed by highly experienced interventional pulmonologists, meaning the safety profile and technical success rates may not be directly replicable in lower-volume or less specialized centers. The lack of systematic surgical or alternative confirmation for negative cytology samples also precludes exact sensitivity calculations.
💡 The Clinical Bottom Line
Minor esophageal mucosal alterations (such as punctate lesions and localized edema) are extremely common following EUS-B-FNA (occurring in nearly 90% of procedures), but they are benign, self-limiting, and clinically insignificant. When performed by trained interventional pulmonologists adhering to meticulous insertion and retraction techniques, EUS-B-FNA maintains an excellent safety profile without severe local or systemic complications, strongly supporting its routine integration into thoracic staging algorithms.