gms | German Medical Science

Intracranial germ cell tumours (GCTs) are rare and predominantly diagnosed between the age of 6 and 14 years in males. They are typically midline tumours of the suprasellar or pineal region. They present with raised intracranial pressure, endocrinological and opthalmological impairment. Diagnosis is based on: clinical symptoms, markers in serum and CSF, neuroimaging, cytological (CSF) and histological confirmation. The elevation of AFP in serum/ CSF (> 25 ng/ml) is typical for a yolk sac tumor component and ß-HCG (> 50 IU/L) for the appearance of a choriocarcinoma. All these aspects are strongly recommended to be examined by a multidisciplinary team (neurosurgeon, oncologist, neuro-radiologist, pathologist) before treatment (including surgery) is started . It is essential to try to perform the correct staging and diagnosis before treatment decisions are made because this can positively influence the results of therapy and outcome. About 25% of all pediatric CNS GCT present as tumors with more than one histology. Histological types are: germinoma and non-germinoma, such as yolk sac tumors, choriocarcinoma, embryonal carcinoma and as so called benign tumors; teratoma. Therapy and prognosis depend on the component with the highest malignancy and on dissemination. It can be expected that about 15% of the germinoma and 20% of the non-germinomatous tumors are metastatic. Bifocal disease appear in about 20% and are treated as non-metastatic. Within the last 20 years craniospinal (CS) irradiation (RT) has been the treatment in Germinoma. With 30 to 24 Gy to the CS axis and a tumor boost between 20 and 16 Gy it is possible to cure about 90% of the patients. The other attempt to treat germinoma is chemotherapy (Carbo-PEI) and local RT (non-metastatic). With this approach survival rates are about 85%. In non-germinoma a combined treatment with Cisplatin as the leading agent is used (PEI) in combination with focal RT or CS RT in respect to dissemination. Event-free survival is around 70%. Incomplete staging is a major risk factor in germinoma. With combined treatment and focal RT mainly ventricular relapses are diagnosed. AFP-level at diagnosis may play an important role for prognosis of non-germinoma. Analysis within the SIOP CNS GCT protocol reveals a prognostic impact of a tumor residue after the end of treatment. In the fourthcoming SIOP CNS GCT II protocol these findings will be addressed. Supported in part by Deutsche Krebshilfe