Purpose: To evaluate the toxicity and efficacy of Iridium-192 high-dose-rate (HDR) endobronchial brachytherapy (EBBT) for the palliation of symptoms caused by relapsed or persistent endobronchial tumors.
Methods and materials: We reviewed the treatment outcomes between 1988 and 1997 in 175 lung cancer patients who underwent HDR EBBT for recurrent or metastatic tumors at The University of Texas M. D. Anderson Cancer Center. One hundred sixty of these patients had previously received thoracic external-beam irradiation. This updated report includes 74 patients from a previous series. Most patients received 3,000-cGy EBBT delivered at a distance of 6 mm and divided into 2 fractions over 2 weeks. Subjective response was assessed by questionnaire at follow-up. Objective response was assessed by physical examination, bronchoscopy, and chest radiograph.
Results: The median actuarial survival for the entire group was 6 months from the time of the first EBBT treatment session. Of the 115 patients (66%) who showed symptomatic improvement, 32% were much improved and 34% were slightly improved. Patients showing improvement survived for significantly longer than those who showed no change or worsening symptoms (7 vs. 4 months, p = 0.0032). Repeat bronchoscopy demonstrated a 78% overall objective response rate that correlated significantly with subjective response and symptom relief. Complications occurred in 19 patients (11% crude rate) with an actuarial complication rate of 13% at 1 year from the time of the first EBBT treatment session. The actuarial hazard for fatal hemoptysis due to EBBT was 5%.
Conclusion: HDR EBBT effectively palliates most patients' symptoms caused by endobronchial lesions. This relief correlates significantly with an overall survival benefit. Treatment complications appear to be few, even for patients who have received prior external-beam irradiation.