INTRODUCTION
Neuroblastoma (NB) is the most common extra-cranial solid tumor in
childhood [1] . Its prognosis depends on the stage, age and
molecular features on diagnosis.
In cases of high-risk (HR) NB, the chances of cure remain poor, with 3-
and 5-year event-free survival rates of 40-50% [2-5] . The
current treatment of HR-NB consists of multimodal approaches that
include surgical resection of the primary tumor, induction chemotherapy,
high-dose myeloablative therapy (HD-MAT) followed by autologous stem
cell transplantation (ASCT), radiotherapy, retinoic acid and
immunotherapy with chimeric anti-GD2 antibody.
Scintigraphy with 123I-meta-iodobenzylguanidine
(123I-MIBG) is recognized to be an effective and
reliable method of staging and evaluating the response to treatment of
NB patients [6] , while meta-iodobenzylguanidine
radiolabeled with iodine-131 (131I-MIBG) has been
successfully used as a targeted treatment, administered alone in
relapsed/refractory HR-NB or combined with chemotherapy and ASCT[17-24] . This treatment exploits the avidity of NB cells in
taking meta-iodobenzylguanidine into the cytoplasm and mitochondria
through norepinephrine transporter channels, potentially delivering a
lethal radiation dose to the target cells [7-9] .
The main aim of this retrospective study was to analyze the feasibility
and toxicity of therapeutic131I-MIBG
(Th-131I-MIBG) followed closely by ASCT conditioned
with HD-MAT with Busulfan and Melphalan (BuMel) in children affected by
HR-NB with residual MIBG-avid disease.
The secondary aim of the study was to evaluate the cumulative risk of
progression/relapse (CRR) and the overall survival (OS) and to analyze
the association of the principal risk factors with outcome.