Endobronchial brachytherapy and external-beam radiotherapy in patients with endobronchial obstruction and extrabronchial extension.

Purpose: To evaluate the efficacy of high-dose rate endobronchial brachytherapy (HDR-EB) with concomitant short-course external-beam radiotherapy (EBRT) in patients with both endobronchial and extrabronchial tumor.

Methods And Materials: Patients with endobronchial disease and extrabronchial lesions greater than 2.5cm were treated with three 5Gy HDR-EB and 37.5Gy EBRT delivered over 3.5 weeks. Flexible fiberoptic bronchoscopy was performed with the patient under conscious sedation, and tumor location, length of lesion, percentage of lumen occlusion, and presence of bleeding were recorded. Fluoroscopic visualization of the guide wire in the catheter tip assisted in demarcating the proximal and distal extent of the intraluminal tumor. 5Gy was prescribed to a distance of 1cm from the catheter and a computerized treatment planning system was used to optimize the dose distribution to the gross target volume with 1.5-2cm margins at the distal and proximal ends. Bronchoscopic and symptomatic response rates were assessed at the third HDR-EB and patients were seen in follow-up every 2 months.

Results: One hundred seventeen endobronchial treatments were delivered to 33 patients with primary carcinoma, and 8 patients with metastatic carcinoma. The median age was 69 (range = 36-94); 95% reported dyspnea; 71% cough and 22% hemoptysis. Seventy-two percent of patients reported resolution of their symptoms and 54% achieved a bronchoscopic response (at least 50% decrease in intraluminal obstruction). In a multivariate logistic model including stage, age, primary tumor type, and Karnofsky performance status (KPS) as predictors, only KPS was statistically associated with bronchoscopic response (OR = 1.1; 95%CI = 1.01-1.13) and palliation of symptoms (OR = 1.3; 95%CI = 1.05-1.59). The overall median survival was 5.2 months and was associated with bronchoscopic response (11 months in responders vs 4 in nonresponders) and symptom resolution (8 months in responders vs 1.5 in nonresponders). In a multivariate Cox survival model with stage, age, primary tumor type, and KPS as predictors, only KPS was significantly associated with survival (RR = 0.92;95%CI = 0.88-0.95).

Conclusions: HDR-EB with concomitant EBRT is an effective treatment regimen for patients with both endobronchial and extrabronchial tumor. Patients with higher performance status are more likely to have resolution of disease and have longer median survival.