Peripheral blood stem cell support for multiple cycles of dose intensive induction therapy is feasible with little risk of tumor contamination in advanced stage neuroblastoma: a report from the Childrens Oncology Group.
BACKGROUND
Poor outcome in Stage 4 neuroblastoma may be improved with increased dose intensity of therapy. We investigated the feasibility of sequential collection and infusion of peripheral blood stem cells (PBSCs) as hematopoietic support for non-myeloablative dose intensive induction chemotherapy given every 21-28 days.


METHODS
Twenty-two children with Stage 4 neuroblastoma (>or=1 year of age) received two cycles of high-dose cyclophosphamide (4 g/m(2)), doxorubicin (75 mg/m(2)), and vincristine (2 mg/m(2)) followed by three cycles of interpatient dose escalating carboplatin (Dose Level 0 = 800 mg/m(2); Dose Level 1 = 1,000 mg/m(2)), high-dose cyclophosphamide (4 g/m(2)), and etoposide (600 mg/m(2)). PBSC were harvested following cycle 2, 3, and 4 in Cohort 1 and infused after each subsequent cycle. In Cohort 2, PBSC were harvested after cycle 2 and split into three aliquots for infusion. Dose limiting toxicity (DLT) and ability to administer cycles within 28 days was assessed.


RESULTS
Sufficient PBSC (>or=2 x 10(6) CD34 cells/kg per infusion) were collected from 17/21 eligible patients with minimal toxicity and no detectable neuroblastoma cells by immunocytology. Carboplatin at 1000 mg/m(2) resulted in DLT of delayed platelet recovery >28 days in 4/8 patients. Despite de-escalation to 800 mg/m(2), platelet DLT occurred in 4/7 Cohort 1 and 3/7 Cohort 2 patients.


CONCLUSIONS
As defined in this protocol, doses of carboplatin were not tolerable with the PBSC dose administered. However, it was feasible to collect sufficient PBSC from small neuroblastoma patients to use as hematopoietic support with minimal risk of tumor contamination and toxicity.
Bensimhon
Pamela
P
Division of Pediatric Hematology/Oncology, Duke University Medical Center, Durham, North Carolina 27710, USA.
Villablanca
Judith G
JG
Sender
Leonard S
LS
Matthay
Katherine K
KK
Park
Julie R
JR
Seeger
Robert
R
London
Wendy B
WB
Yap
John Stephen F
JS
Kreissman
Susan G
SG
D000970:Antineoplastic Agents / Q000627:therapeutic use*; D016190:Carboplatin / Q000008:administration & dosage / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D003520:Cyclophosphamide / Q000008:administration & dosage / Q000009:adverse effects; D018572:Disease-Free Survival; D004317:Doxorubicin / Q000008:administration & dosage / Q000009:adverse effects; D005047:Etoposide / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D019650:Hematopoietic Stem Cell Mobilization; D006801:Humans; D007223:Infant; D053208:Kaplan-Meier Estimate; D008297:Male; D020714:Maximum Tolerated Dose; D009447:Neuroblastoma / Q000401:mortality / Q000628:therapy*; D036102:Peripheral Blood Stem Cell Transplantation; D014750:Vincristine / Q000008:administration & dosage / Q000009:adverse effects
D000970:Antineoplastic Agents; D014750:Vincristine; D005047:Etoposide; D004317:Doxorubicin; D003520:Cyclophosphamide; D016190:Carboplatin