Germinoma located in the basal ganglia in an 8-year-old girl

The authors describe a unique case of an 8-year-old girl with a germinoma located in the left basal ganglia. Medical history begins 5 months before with a central diabetes insipidus, loss of weight (5 kg at admission), vomiting and asthenia. Computed tomography (CT) and cranial magnetic resonance imaging (MRI) are performed and demonstrate a left basal ganglia tumour (nucleus lentiformis). Diabetes insipidus is considered as non-visible germinoma localization on the pituitary stalk rather than as a possible consequence of peri-tumoural oedema surrounding the hypothalamus. Spinal MRI is normal. Neurological as well as general examination is normal.

The first hypothesis is low-grade glioma, but pathological examination following a stereotactic biopsy of the lesion reveals a cerebral germinoma. A few days before the biopsy, the girl experienced a mild left facial palsy, and CT scans at the time of biopsy reveals an intra-tumoural haemorrhage. Alpha fetoprotein and human chorionic gonadotrophin were negative as blood and cerebrospinal fluid markers, whereas placental alkaline phosphatase was positive on immunohistochemical profile of the tumour samples. Dedicated chemotherapy, followed by focal irradiation (40 Gy, 30 sessions, 45 days; SIOP CNS GCT 93 protocol), is performed with a complete response. The outcome is good (Glasgow Outcome Scale=I), without any cognitive impairment and the persistence of a mild facial palsy and a slight right arm dystonia on last neurological examination. There is still no evidence of tumour recurrence.