Abstract
This patient was a 37-year-old woman. An abnormal shadow was found in the hilar portion on a chest radiograph during examination. The tumor showed a lobular shape on chest CT and MRI. The tumor consisted of multiple cysts and substantial parts. Multilocular thymic cysts merging with a tumor was doubtful. A thymothymectomy with thoracoscopically assisted surgery was performed for this mediastinal tumor. A part of the tumor had invaded the middle lobe and required combined resection. The postoperative pathological diagnosis was basaloid carcinoma, which developed in the background of a multilocular thymic cyst. We added postoperative radiotherapy to the treatment of this patient, and there has been no recurrence after two postoperative years. Thymic basaloid carcinoma, including our case, is a very rare disease classified in the low-malignancy group; 37 cases have been reported to date. We discuss its diagnosis, treatment, and considerations of its biochemical characteristics from the literature.
