# An Evaluation of Endobronchial Ultrasound-Transbronchial Needle Aspiration (EBUS-TBNA): Molecular Diagnoses and Patient Satisfaction

## TL;DR

This study evaluates the effectiveness of EBUS-TBNA in diagnosing lung cancer and other conditions, finding it useful for identifying targetable mutations and high patient satisfaction.

## Contribution

The study is the first in the UK to evaluate EBUS-TBNA's role in identifying targetable mutations for immunotherapy and assess patient satisfaction.

## Key findings

- 15.27% of EBUS-TBNA procedures for primary lung cancer revealed clinically actionable genetic mutations.
- Patient-reported pain was significantly lower than expected, indicating a less painful procedure than anticipated.
- Most patients (55.85%) waited less than a week for the EBUS-TBNA procedure.

## Abstract

Background and aim: Endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive procedure that collects biopsies in patients with mediastinal and/or hilar lymphadenopathy, often in lung cancer or sarcoidosis. Cancerous biopsies can undergo molecular testing to identify mutations, which may be targeted by immunotherapy. The role of EBUS-TBNA in molecular outcomes has not been studied previously in the United Kingdom. This study also examines patient demographics and satisfaction to comprehensively evaluate EBUS-TBNA. This study aimed to evaluate the EBUS-TBNA service at University Hospital Southampton (UHS), focusing on patient demographics, satisfaction, diagnostic outcomes, procedural statistics, and identifying targetable mutations for immunotherapy.

Method: A total of 306 patients were studied retrospectively, and 39 were studied prospectively, using a questionnaire. Data on their characteristics, reports, diagnoses, and molecular tests were recorded and analyzed using SPSS version 29.

Results: A total of 47.12% (n = 131) patients were diagnosed with primary lung cancer, 23.38% (n = 65) with sarcoidosis, 9.71% (n = 27) with metastatic cancer, and 1.95% (n = 7) with other diagnoses, such as tuberculosis. Primary lung cancer was categorized as adenocarcinoma (52.31%, n = 68), squamous cell carcinoma (SCC) (25.38%, n = 33), and small cell carcinoma (SCLC) (16.92%, n = 23). Of the primary cancer cases, 60.31% (n = 79) underwent molecular testing. In this cohort, 29.41% (n = 20) of adenocarcinoma cases tested positive for a targetable mutation as follows: 85% (n = 17) were KRAS G12C, and 15% (n = 3) were the EGFR E19del. Overall, 15.27% (n = 20) of EBUS-TBNA procedures for primary lung cancer revealed a clinically actionable variant. Of the 39 patients surveyed, there was a significant difference between the pain experienced (median = 2/10, IQR = 4) and the expected pain (median = 5/10, IQR = 6), as assessed by a Wilcoxon signed-rank test (z = -2.91, p = 0.004). The average staff experience during the EBUS was 9.87/10 (SD = 0.47), and 55.85% (n = 21) waited <1 week for the procedure.

Conclusions: EBUS-TBNA’s role in diagnosing various conditions, especially primary lung cancer, is clear. Clinically, EBUS-TBNA provides genetic diagnoses, which can enable immunotherapy. Patient satisfaction is high, with patients expressing relief after the procedure and finding the staff exceptional.