High-dose 131I-metaiodobenzylguanidine therapy in patients with high-risk neuroblastoma in Japan.
OBJECTIVE
The aim of the study was to investigate the outcomes and prognostic factors of high-dose 131I-metaiodobenzylguanidine (131I-MIBG) therapy in patients with refractory or relapsed neuroblastoma (NBL) in Japan.


METHODS
We retrospectively analyzed 20 patients with refractory or relapsed high-risk NBL who underwent 131I-MIBG therapy with an administration dose ranging from 444 to 666 MBq/kg at Kanazawa University Hospital, Japan, between September 2008 and September 2013. We focused on measurements regarding their initial responses, prognostic factors, survivals, and toxicities following 131I-MIBG therapy using our hospital data and questionnaires from the hospitals that these patients were initially referred from. Furthermore, we performed Kaplan-Meier survival analysis to evaluate event-free survival (EFS) and overall survival (OS).


RESULTS
In 19 patients with complete follow-up data, the median age at first 131I-MIBG treatment was 7.9 years (range 2.5-17.7 years). Following 131I-MIBG therapy, 17 of the 19 patients underwent stem-cell transplantations, and their treatment response was either complete (CR) or partial (PR) in three and two cases, respectively. The EFS and OS rates at 1 year following 131I-MIBG therapy were 42% and 58%, respectively, and those at 5 years following 131I-MIBG therapy were 16% and 42%, respectively. Using the two-sample log-rank test, the OS time following 131I-MIBG therapy was significantly longer for < 3-year time interval between the initial diagnosis and 131I-MIBG therapy (p = 0.017), Curie score < 16 just before 131I-MIBG therapy (p = 0.002), without pain (p = 0.002), without both vanillylmandelic acid (VMA) and homovanillic acid (HVA) elevation (p = 0.037) at 131I-MIBG therapy, and with CR or PR following 131I-MIBG therapy (p = 0.015). Although severe hematological toxicities were identified in all 19 patients, severe nonhematological toxicity was not recorded in any patient, except for one patient with grade 3 anorexia and nausea.


CONCLUSIONS
High-dose 131I-MIBG therapy in patients with refractory or relapsed high-risk NBL can provide a favorable prognosis without severe nonhematological toxicities. Better prognosis may be anticipated in patients with the initial good response, no pain at 131I-MIBG therapy, no VMA and HVA elevation at 131I-MIBG therapy, low Curie score (< 16) just before 131I-MIBG therapy, and short time interval (< 3 years) between the initial diagnosis and 131I-MIBG therapy.
['Kayano|Daiki|D|', 'Wakabayashi|Hiroshi|H|', 'Nakajima|Kenichi|K|', 'Kuroda|Rie|R|', 'Watanabe|Satoru|S|', 'Inaki|Anri|A|', 'Toratani|Ayane|A|', 'Akatani|Norihito|N|', 'Yamase|Takafumi|T|', 'Kunita|Yuji|Y|', 'Hiromasa|Tomo|T|', 'Takata|Aki|A|', 'Mori|Hiroshi|H|', 'Saito|Shintaro|S|', 'Araki|Raita|R|', 'Taki|Junichi|J|', 'Kinuya|Seigo|S|']
D019797:3-Iodobenzylguanidine D002648:Child D002675:Child, Preschool D005260:Female D006801:Humans D007564:Japan D053208:Kaplan-Meier Estimate D008297:Male D009447:Neuroblastoma D011829:Radiation Dosage D011879:Radiotherapy Dosage D012189:Retrospective Studies D012306:Risk D016896:Treatment Outcome
131I-metaiodobenzylguanidine Relapsed neuroblastoma Internal radiation therapy Radionuclide therapy Refractory neuroblastoma