Abstract: Objective To evaluate the minimum dosage of efficiency in diagnostic radiation for intracranial germinoma to reduce the patients' unnecessary radiation.Methods Retrospective analysis were performed in 75 germinoma patients with 104 lesions totally that were clinically verified by radiotherapy, including 51 patients with single lesion, 19 patients with two lesions and 5 patients with three lesions. The response case number were analyzed by chi-squire examination at the radiation dosage of 10 Gy and 20 Gy.Results Statistical analysis showed no difference in the number of responsive patients between 10 Gy and 20 Gy radiation dosage.Conclusion For intracranial germinoma, 10 Gy is the preliminary minimum dosage of diagnostic radiation to confirm the suspected germinoma.

Key words: non-germinoma germ cell tumors, germinoma, diagnostic radiation, radiotherapy