Management of malignant airway obstruction: Clinical and dosimetric considerations using an iridium-192 afterloading technique in conjunction with the neodymium-YAG laser

Abstract

Fourteen patients with malignant airway obstruction have had 21 placements of a flexible nylon catheter for afterloading Iridium-192 using the flexible fiberoptic bronchoscope. Prescribed therapy was completed in 13 patients (18 courses). All patients had prior full-dose external irradiation, and no effective surgical or chemotherapeutic options remained. While many have had a trial of neodymium-YAG (yttrium-aluminum-garnet) laser therapy alone, eight patients received laser treatment one to three weeks prior to planned brachytherapy to provide immediate relief of symptoms and/or facilitate access and safe catheter placement. Most patients (64%) had recurrent squamous cell lung cancer. A dose of 3000 cGy is currently specified to 5 mm and 10 mm in the bronchus and trachea, respectively. Nine of the 13 treated patients have had follow-up bronchoscopy at approximately three months post-treatment with improvement documented in seven and progression in two patients. One patient was clinically improved without follow-up bronchoscopy, and three patients have had insufficient follow-up. A single patient treated with laser and 6000 rad at 5 mm developed a bronchoesophageal fistula. No other complication has been observed. The technique is simple and safe with the use of laser therapy when needed and appears to offer effective palliation in most patients even when standard therapy is exhausted.