Thymic basaloid carcinoma with aggressive invasion of the lung and pericardium: report of a case.

We report a case of basaloid carcinoma of the thymus, invading the lung and pericardium. The patient was a 72-year-old man who suffered thoracic trauma in a fall and was taken to his family physician. Computed tomography revealed a huge mediastinal tumor with cystic components, pressing into the lung. He was referred to our hospital, where magnetic resonance imaging showed suspicious invasion of the pericardium and mediastinum. We made an assumed diagnosis of a mediastinal malignancy and performed mediastinal tumor resection. The tumor was adherent to the lung, pericardium, and left innominate vein. The final pathological diagnosis was a basaloid carcinoma of the thymus. Basaloid carcinoma is often a component of a multiloculated thymic cyst (MTC) and should be considered when MTC is identified within an anterior mediastinal tumor.