CT-guided interstitial brachytherapy of primary and secondary lung malignancies: results of a prospective phase II trial.

Background And Purpose: CT-guided interstitial brachytherapy of primary lung malignancies and pulmonary metastases represents a novel interventional technique, combining conventional high-dose-rate (HDR) iridium-192 ((192)Ir) brachytherapy with modern CT guidance for applicator positioning and computer-aided 3-D radiation treatment planning. The purpose of this study was to assess safety and efficacy of this technique.

Patients And Methods: 30 patients with 83 primary or secondary lung malignancies were recruited in a prospective nonrandomized trial (Table 1). After catheter positioning under CT fluoroscopy, a spiral CT was acquired for treatment planning (Figure 1). All but two patients received a defined single dose (coverage > 99%) of at least 20 Gy from a (192)Ir source in HDR technique.

Results: Adverse effects were nausea (n = 3, 6%), minor (n = 6, 12%) and one major pneumothorax (2%). Post intervention, no changes of vital capacity and forced expiratory volume could be detected. The median follow-up period was 9 months (1-21 months) with a local tumor control of 91% at 12 months (Figure 2).

Conclusion: CT-guided interstitial brachytherapy proved to be safe and effective for the treatment of primary and secondary lung malignancies.