Tc-99m sestamibi scintigraphy : An effective method to predict the response of thymoma after radiotherapy

An 80-year-old woman was hospitalized because of chest pain and dyspnea. A large mediastinal mass was shown on radiographs. Computed tomographic scans show a soft tissue mass in the upper anterior mediastinum. Fine-needle aspiration of the mass showed a malignant thymoma. The patient underwent radiotherapy after computed tomography-guided computerized treatment planning and received 64 Gy within 6.5 weeks (conventional fractionation). At the end of radiotherapy, new computed tomographic scans and MIBI scintigraphs were obtained. Both showed a necrotic area in the center of the mass as a result of its response to radiotherapy.