Treatment
All 41 patients underwent intensive multidrug induction chemotherapy in
median 5 cycles (range = 4−7 cycles). A sufficient amount of peripheral
blood stem cell grafts were collected from 39 patients during
chemotherapy, while auto-bone marrow grafts were collected from 2
patients because of insufficient peripheral stem cell collection.
Resection of the primary tumor was performed in 11 patients before HDC.
Radiation therapy for the primary site was administered in 29 patients.
Before HDC, of the 41 patients, 14 (33%) (MYCN -amplified
high-risk neuroblastoma, 11; MYCN -non-amplified high-risk
neuroblastoma, 3; P = 0.051) showed complete response or very
good partial response (CR/VGPR). Of 26 patients, 7 (27%) who did not
undergo resection before HDC showed CR/VGPR. Of 41 patients, 15 (37%)
received a reduced dose of thiotepa and melphalan as HDC because of
renal function deterioration. In addition, 24 (59%) patients whose
guardians requested off-label use underwent retinoic acid therapy, and 8
(20%) patients with poor response after treatment underwent a second
SCT using cord blood stem cells, expecting immunological effects. No
patients underwent anti-GD2 antibody immunotherapy.