BACKGROUND Intraluminal brachytherapy has become an established treatment for major airway occlusion by relapsed or persistent inoperable endobronchial tumors. The aim of this study was to compare the palliation improvement pre- and post-radiotherapy. METHODS The study group was 95 patients with the diagnosis of inoperable lung cancer who were eligible for HDR brachytherapy. Fiber-optic bronchoscopy was performed and the level and degree of endobronchial obstruction were estimated in terms of bronchial obstruction index. Endobronchial irradiation was delivered using remote HDR afterloading brachytherapy with iridium-192. Brachytherapy was delivered at weeks 1, 2 and 3 at 7.5 Gy per fraction or at weeks 1 and 2 at 10 Gy per fraction. All patients were evaluated at the beginning and at the third month of therapy. Using Speiser's symptomatic scoring criteria, the severity of symptoms (dyspnea, cough, hemoptysis and postobstructive pneumonia) was weighted. Bronchoscopic findings at the initial evaluation and at the third month were also scored. Surviving patients were followed up for a minimum of 3 months with a mean of 7.5 +/- 5.35 months (median: 6 months). RESULTS All the symptoms and bronchial obstruction improved significantly after brachytherapy (P < 0.05). The most responding symptoms were dyspnea and hemoptysis. The factors determining the complete response were evaluated; age, staging, histological type, lesion localization and previous history of radiotherapy did not seem to determine the complete response (P > 0.05). CONCLUSIONS All the symptoms and bronchial obstruction index seemed to improve after brachytherapy. However, it is difficult to predict the response before the therapy.