In view of the high relapse rate following chemotherapy for patients with advanced neuroblastoma (NB) and primitive neuroectodermal tumors (PNET), we designed a novel chemotherapy program which incorporated the iron chelator deferoxamine. The purpose of the deferoxamine was to sensitize the cells to standard chemotherapy. The D-CECaT regimen contained (in mg/m2): deferoxamine 4500 during days 1-5; cyclophosphamide 600 mg over days 6 and 7; etoposide 300 mg over days 7 and 8; carboplatin 100 mg over days 7 and 8; and thiotepa 30 mg over days 6-8. Between October 1989 and May 1992 we entered 23 advanced NB and two PNET patients. Sepsis occurred in four courses, nausea and vomiting in 30 courses, and 50 courses required blood and platelets. Responses observed in previously untreated patients with stage III NB: six out of six CR (17+ to 41+ months), with stage IV NB, nine out of 11 CR (14+ to 28+ months), two out of 11 VGPR (22+ months), with stage IV PNET two out of two CR (1+ to 35+ months). With previously treated and failed stage IV NG, two out of six VGPR for 19+ and 20 months, and four out of six PR 1, 8, 9 and 11 months. Median survival for 19 new patients was 22+ months (6 to 41+ months; two patients in CR died at 7 months during adjuvant autologous marrow transplant). In conclusion, D-CECaT is an effective initial cytoreductive regimen for advanced stage NB/PNET patients. Additional patients and studies are required to determine its use as an alternative to autologous bone marrow transplantation.