Abstract
Intracranial germ cell tumors (GCTs) include two categories: germinoma and non germinoma. The pineal gland and suprasellar are the most common site of involvement. The patient is a 14-year-old boy who presented with paralysis of upward gaze, polyuria, polydipsia and diplopia. Examination of vertical eye movements was impaired. Puberty then progressed to stage 3 of Marshall - Tanner and had stopped. In laboratory studies, the patient had anterior hypopituitarism and diabetes insipidus (DI). In pituitary and hypothalamic MRIs, a mass-like enlargement of the pituitary stalk and pineal region was seen, but due to the small size of the lesions, stereotactic biopsy was not possible. During this time, the patient developed recurrent attacks of hydrocephalus. Serum and CSF β-subunit of Human chorionic gonadotropin levels were negative. Treatment was not started because different lesions could cause disease in this area. After one year, a biopsy was performed and the germ cell tumor was diagnosed. Chemotherapy was started and after treatment the vision disorder and diplopia disappeared, but DI and pituitary dysfunction remained. Treatment of intracranial germinoma is multidisciplinary. GCTs are very sensitive to radiation therapy. They are treated with combination of chemotherapy, radiotherapy, surgery, endocrine therapy and have a good prognosis.