High Dose Rate Remote Afterloading Brachytherapy for Lung and Esophageal Cancer.

High dose rate brachytherapy for lung and esophageal cancer is performed by placing a high activity Iridium 192 source into the lumen of the airway of esophagus. Because of the high activity of the source it remains in place for only a matter of minutes, and fractionated treatments are feasible. Before this development, conventional dose rate brachytherapy required hospitalization with attendant patient discomfort, expense, and complicated radiation safety requirements. The development of high activity remote afterloading machines has removed these practical disadvantages and has led to a great interest in the use of this technology for radical treatment and palliation of obstructing malignancies. There are several unresolved issues concerning this modality for both lung and esophageal cancer. For both diseases, optimal dose and fractionation schemes are not well defined but the palliative benefits for recurrent lung cancer have been clearly shown. The use of a brachytherapy boost following radical external beam radiation therapy of lung cancer is not proven to be advantageous. For esophageal cancer, the value of brachytherapy for palliation is not established. However, there are preliminary data to suggest that it can improve outcome when used routinely after radical treatment with external beam radiation therapy.