Brachytherapy of esophageal cancer: Some considerations on dose to adjacent normal tissue structures

An estimate of the maximum dose reaching the adjacent normal tissue structures (spinal cord, posterior pericardium, and left and right hilum) was obtained from radiographs in the anteroposterior and lateral views for patients who received high dose rate intraluminal brachytherapy for esophageal cancer. Doses to the posterior pericardium ranged from 1.2 to 5.15 Gy (20.33% to 64.38%), 0.8 to 2.65 Gy (13.3% to 33.1%) to the spinal cord, 2.2 to 8.17 Gy (27.5% to 81.7%) to the left hilum, and 0.98 to 11.46 Gy (16.3% o 114.6%) to the right hilum, depending on the dose prescribed. Doses to the spinal cord showed the least variability with an SD of 0.98, while doses to the right hilum showed the greatest variability with an SD of 5.66. Using one-tailed single-sample t tests, the mean spinal cord dose, the mean posterior pericardial dose, and the mean left and right hilar doses were found to be significantly less than the tolerance doses of these structures (P < .01). High dose rate intraluminal brachytherapy is a safe and effective method of palliation in esophageal cancer, either alone or as a boost after external beam radiotherapy.