[A case of primary intracranial T cell type malignant lymphoma, radiologically resembling germ cell tumor and presenting hypopituitarism].

A 21-year-old man was hospitalized with complaints of headache, nausea, polyuria, reduced body hair and reduced libido. Plain CT scan and MRI revealed multiple tumors in the pineal and suprasellar regions, and in the dorsal aspect of the medulla oblongata. Endocrinological examination showed hypopituitarism due to hypothalamic dysfunction. Replacement therapy with hydrocortisone was started preoperatively. Suprasellar tumor was explored. Postoperative CT scan and MRI showed marked diminishment of not only suprasellar tumor, but also tumors in the two other regions. These tumors were supposed to be sensitive to corticosteroid hormone. Histopathological diagnosis was T cell type malignant lymphoma. The patient was followed up for 10 months post-operatively with no recurrence on CT scan. Primary intracranial malignant lymphoma is not a rare disease today. However, primary intracranial T cell type lymphoma is extremely rare. Hypopituitarism due to suprasellar malignant lymphoma is also rare, and only 3 such cases have been reported previously. In our case, the tumor was located in the pineal and suprasellar regions, and the dorsal aspect of the medulla oblongata. Such disseminated malignant lymphoma as ours shows radiological resemblance to germ cell tumor. No such diseminated malignant lymphoma has been reported previously. We think that, in its radiological and clinical features, our case is very suggestive of primary intracranial malignant lymphoma.