Computed Tomography-Guided Interstitial High-Dose-Rate Brachytherapy in the Local Treatment of Primary and Secondary Intrathoracic Malignancies

Abstract

Image-guided interstitial (IRT) brachytherapy (BRT) is an effective treatment option as part of a multimodal approach to the treatment of isolated lung tumors. In this study, we report our results of computed tomography-guided IRT high-dose-rate (HDR) BRT in the local treatment of inoperable primary and secondary intrathoracic malignancies. Between 1997 and 2007, 55 patients underwent a total of 68 interventional procedures for a total of 60 lung lesions. The median tumor volume was 160 cm³ (range, 24-583 cm³). Thirty-seven patients were men and 18 were women, with a median age of 64 years (range, 31-93 years). The IRT-HDR-BRT delivered a median dose of 25.0 Gy (range, 10.0-32.0 Gy) in twice-daily fractions of 4.0 to 15.0 Gy in 27 patients and 10.0 Gy (range, 7.0-32.0 Gy) in once-daily fractions of 4.0 to 20.0 Gy in 28 patients. The median follow-up was 14 months (range, 1-49 months). The overall survival rate was 63% at 1 year, 26% at 2 years, and 7% at 3 years. The local control rate for metastatic tumors was 93%, 82%, and 82% and for primary intrathoracic cancers 86%, 79%, and 73% at 1, 2, and 3 years, respectively. Pneumothoraces occurred in 11.7% of interventional procedures, necessitating postprocedural drainage in one (1.8%) patient. In patients with inoperable intrathoracic malignancies, computed tomography-guided IRT-HDR-BRT is a safe and effective alternative to other locally ablative techniques.