P2.18-13 Endobronchial Brachytherapy: A Single Institutional Experience

Abstract

High Dose Rate Endobronchial Brachytherapy (HDR-EB) allows treatment of endobronchial lung cancer with minimal radiation of surrounding tissues. It can be both applied as radical intent in local disease or as palliation in metastatic or non-curative setting. The aim of this study is to describe clinical characteristics, complications and survival of a cohort patients treated with HDR-EB as radical intent. Retrospective analysis of consecutive patients undergoing radical HDR-EB in our centre since 2010. Clinical, functional and survival variables were recorded, as well as those related to radiation. HDR-EB was performed after placement of the afterloading catheter in the target bronchus with a flexible bronchoscope. All treatment was delivered weekly. Simulation CT and dosimetry was performed before each fraction. Dose was 5Gy/fr, prescribed at 100% of the implant. 16 patients were analysed, 15 (94%) males, age 69 (±8) years-old, 3 (19%) were active and 13 (81%) former smokers. Lung function was FEV1 62.3% (±21%), DLCO 60.5% (±13%). Pathological diagnose included in-situ carcinoma (n=1, 6%) and invasive squamous cell carcinoma (n=15, 94%). T staging was T1 in 10 (62.5%) patients, T2 in 3 (18.8%) patients and T4 in 1 (6.3%) patient. All patients had N0 staging. 2 patients had exclusive endobronchial disease. 6 patients received 3 (n=3, 18.6%) and 4 (n=3, 18.6%) fractions after external beam radiotherapy as a boost. 10 patients received 5 (n=2, 12.5%) or 6 (n=8, 50%) fractions as exclusive radical HDR-EB. 2 complications were reported: obstructive pneumonitis (n=1) and bronchial stenosis (n=1). Neither deaths nor haemoptysis occurred in relation with the technique. Mean follow-up was 29 (±21) months. Mean overall survival was 29.0 (±22) months. Mean disease free-survival was 24.9 (±21) months. 4 (25%) progressions were observed, of which 3 (19%) were local progression. Patients who received boost strategy HDR-EB showed an increased overall survival compared to radical intent (38.2 vs 24.8, p>0.05) and a increased median free-survival; which showed no statistical significance. HDR-EB is a safe technique applicable in radical intention. Longer survival has been described in patients who received boost strategy. Prospective studies are needed to determine long-term benefits.