Endobronchial brachytherapy for recurrent thymoma showing endobronchial polypoid growth

The authors report a case of recurrent thymoma displaying endobronchial polypoid growth. Initially, the patient had invasive thymoma with intracaval growth into the right atrium. He was treated with multimodality therapy consisting of chemotherapy, surgical resection, and radiotherapy (50.4 Gy). Both 3 years and 6 years after the initial treatment, the tumor recurred outside the reconstructed superior vena cava. The patient was treated with repeated radiotherapy (50.4 Gy and 40 Gy), and remission was achieved. Eight years after the first therapy, an endobronchial polypoid lesion was detected in the right upper lobe bronchus and was histologically found to be thymoma. Endobronchial high-dose rate brachytherapy (20 Gy at 3 mm/5 fractions) was carried out for palliation because the recurrent tumor occurred outside of the superior vena cava area, which had been reirradiated. After the treatment, the endobronchial tumor shrunk remarkably in size without adverse effects. No tumor regrowth has been noted after a follow-up of 10 months.