Patterns of relapse in high-risk neuroblastoma patients treated with and without total body irradiation
Menée sur 74 patients pédiatriques traités pour un neuroblastome à haut risque (âge médian au diagnostic : 3,5 ans), cette étude analyse les formes de récidive après une irradiation corporelle totale par voie systémique
Purpose : External beam radiation to initial sites of disease may influence relapse patterns in high-risk neuroblastoma. However, the effect of systemic irradiation using total body irradiation (TBI) on anatomic patterns of relapse has not previously been investigated. Methods and Materials : We retrospectively analyzed patients receiving definitive treatment for high-risk neuroblastoma with subsequent relapse in bony metastatic sites with relapse between January 1, 1997 and December 31, 2012. Anatomic sites of disease, defined by metaiodobenzylguanidine (MIBG) avidity, were compared at diagnosis and at first relapse. Fisher’s exact test was performed to compare relapse in initially involved sites between patients treated with and without TBI. Results : 74 patients with a median age at diagnosis of 3.5 years (range 0.3-15.3 years) relapsed in 227 sites of MIBG-avid metastatic disease with a median time to relapse of 1.8 years. Of the 227 sites of first relapse, 154 sites (68%) were involved at diagnosis. When comparing relapse patterns in patients treated with and without TBI: 12 of 23 patients (52%) treated with TBI relapsed in at least one previously MIBG-avid site of disease whereas 40 of 51 patients (78%) treated without TBI relapsed in at least one previously MIBG-avid site of disease (p=0.03). Conclusions : Patients treated with systemic radiation in the form of TBI were significantly less likely to relapse in prior sites of disease. These findings support further investigation into the role of radiopharmaceutical therapies in curative multimodality therapy.