Influence of Total Laryngectomy on spinal Cord Dosein Advanced Laryngeal Cancers / 대한치료방사선과학회지

ABSTRACT

PURPOSE: This analysis was to evaluate the radiation dose around a tracheostoma and spinal cord in the case of advanced laryngeal cancers in which a total laryngectomy was done before radiotherapy. METHODS AND MATERIALS The radiation dose around a tracheostoma and spinal cord was measured by thermoluminescence and film dosimety in the phantom. Radiotherapy treatment planning was done in 12 cases of advanced laryngeal cancer and compared with the measured dose in the phantom. RESULTS: Mean spinal cord doses in the phantom by thermoluminescence dosimetry were 86.4% (with a tracheostoma), 80.1% (without a tracheostoma). and the difference was 6.3%. Mean spinal cord doses in the phantom by film dosimetry were 84.7% (with a tracheostoma), 79.0% (without a tracheostoma), and the difference were 5.7%, Calculated spinal cord doses in the phantom were 84.0% (with a tracheostoma), 78.0% (without a tracheostoma), and the difference was 6.0%. Mean calculated spinal cord doses in 12 patients were 83.1% (with a tracheostoma), 76.9% (without a tracheostoma), and the difference was 6.2%. Measured dose of lateral and posterior wall of the tracheostoma by film was low (depth of maximum dose 12 mm). CONCLUSION: In the treatment planning of the advanced laryngeal cancers, the radiation dose of the tracheostoma and spinal cord should be evaluated and be followed by an appropriate management such as a bouls or a brachytherapy boost if the dose around the tracheostoma is low.