Treatment results of intracranial germinoma as a function of the irradiated volume

Between 1962 and 1986, 70 patients were treated with radiation for confirmed or suspected intracranial germinoma at our hospital. The diagnosis was based on histology in 30 cases, cerebrospinal fluid (CSF) cytology in 12 cases, and on clinical and radiological findings in the remaining 28 cases. The target of radiation was the primary tumor site in 34 cases (Group A), the entire neuraxis in 22 cases (Group B), the whole brain in 4 cases (Group C), and the ventricle plus spine in 6 cases (Group D). Four patients were not included in the above groups for various reasons. The average radiation dose was 50-55 Gy to the tumor, 30 Gy to the whole brain, and 24 Gy to the spinal axis. The 5- and 10-year survival rates of the 68 primary cases in which radiotherapy was completed were 86% and 79%, respectively. The survival and relapse-free survival rates for the above 4 groups did not differ significantly, although slightly better results were seen in Groups B and C. Five cases in Groups A and D developed intracranial recurrence, 4 adjacent to the primary site but 1 distant from it, whereas no intracranial recurrence was found in the whole-brain-treated groups (B and C). One patient in Group B developed spinal metastasis, which was possibly due to inadequate radiation fields, and another in Group B developed abdominal metastasis via the shunt tube. Craniospinal irradiation should be administered to the patients with demonstrated meningeal seeding or with a positive CSF cytology. For cytology-negative cases with no evident metastasis, irradiation of the tumor plus a wide margin is usually sufficient, but craniospinal irradiation should be considered when the disease extends along the ventricular walls or is present in both pineal and suprasellar regions.