Isolated central nervous system relapse in patients treated successfully with cisplatin-based chemotherapy for testicular cancer has been described infrequently. In a retrospective analysis we identified this complication in six of 417 patients. Five of the six patients had advanced pulmonary dissemination at onset of chemotherapy, and post-chemotherapy surgery did not reveal viable tumour tissue in any of these cases. All six patients developed a single cerebral metastasis during complete remission a median four months after discontinuation of chemotherapy. Five patients were treated with surgery and subsequent radiotherapy, one patient with irradiation alone. Three patients are alive relapse-free 19, 62 and 86 months after diagnosis of cerebral relapse. One patient was alive with cerebral disease for 12 months without evidence of systemic recurrence. Our data demonstrate that the brain may act as a sanctuary site in chemotherapy-treated testicular cancer. A review of the literature shows that an isolated cerebral relapse is an extremely rare complication, but carries a relatively favourable prognosis.