A Case of Synchronous Occurrence of Intracranial Germinoma and Systemic Sarcoidosis

Although the synchronous occurrence of testicular seminoma and systemic sarcoidosis has been reported, that of intracranial germinoma and systemic sarcoidosis is unknown. A 26-year-old man presented with symptoms of panhypopituitarism and consciousness disturbance. Imaging demonstrated a large nodule in the upper right lung field and swelling of multiple bilateral pulmonary and mediastinal lymph nodes in addition to the bifocal pineal and suprasellar tumors with obstructive hydrocephalus. The pathological diagnosis of the intracranial bifocal tumors was pure germinoma, whereas that of the mediastinal lymph nodes was epithelioid granuloma. Three courses of chemotherapy using carboplatin and etoposide were administered, followed by whole ventricle irradiation. The intracranial tumors completely disappeared, but the lung nodule and mediastinal lymph nodes progressed. Whole-body fluorine-18-fluorodeoxyglucose positron emission tomography demonstrated accumulation in the mediastinal lymphadenopathy, lung masses, and multiple lymph nodes of the whole body. Transbronchial lung biopsy revealed epithelioid granuloma with multinucleated giant cells. In conjunction with the high blood concentration of angiotensin-converting enzyme and soluble interleukin-2 receptor, these findings established a diagnosis of sarcoidosis. This is the first report of synchronous occurrence of intracranial germinoma and sarcoidosis. Such coexistence is extremely rare, but we should mind that sarcoidosis can occur with intracranial germinoma.