[A case of isolated gonadotropin deficiency secondary to glioma in septum pellucidum].

A 21-year-old man, who had had normal sexuality, noticed a decrease in libido and potency as well as loss of ejaculation. Endocrinological evaluation showed normal serum levels of gonadotropins but a low testosterone level. The response to clomiphene citrate was poor while the response to luteinizing hormone-releasing hormone and human chorionic gonadotropin were within normal limits. By the examination of brain computerized tomography a tumor was detected in the septum pellucidum and was resected. Histologically it proved to be a mixed tumor composed of astrocytoma and oligodendroglioma. Two months after the operation the patient had recovered normal sexual functions and the endocrinological functions, including the responsiveness to clomiphene citrate, had been restored. This case suggests the existence of some stimulatory fiber for the secretion of luteinizing hormone in the septum pellucidum.