I-131 MIBG MYOCARDIAL UPTAKE IN LOCALLY ADVANCED AND METASTATIC NEUROBLASTOMA PATIENTS: DOES IT CARRY A PROGNOSTIC SIGNIFICANCE? KOTB, M.(1), RIAD, R.(1), FAWZY, M.(2), EL-WAKIL, M.(3), ZAHER, A.(1) and OMAR, W.(1). Departments of: (1) Nuclear Medicine, NCI, Cairo University, (2) Pediatric Oncology, NCI, Cairo University and (3) Clinical Oncology, Faculty of Medicine, Beni Suef University.

Neuroblastoma is the most common solid extra cranial malignancy in children younger than 15 years. Though there are many prognostic factors for neuroblastoma, none of them is considered to provide enough additional value to be used in clinical practice. Radio-iodinated Metaiodobenzylguanidine
(MIBG) is a functioning analog of norepinephrine taken up by sympathetic neurons and considered very good radiopharmaceutical for diagnosis of
neuroblastoma . 
Aim of the work : In this work, we are looking for a possibly relevant correlation between myocardial I-131 MIBG extent of uptake and outcome in
neuroblastoma to be further used as a prognostic value.
Patients: This study included 38 pediatric patients with pathologically
proven stage III & IV neuroblastoma. Twenty one of the study patients
(53.85%) were males and 18 (46.15%) were females with a ratio of 1.17 to 1.0 respectively. Their age ranged from 6 months to 12 years, with a mean of 4.8±3.3 years. All patients were treated with neoadjuvant chemotherapy
according to protocols issued at the Pediatric Oncology Department, NCI
(OPEC, OJEC ICE, CADO). Assessment of response to combined modality
treatment was defined in terms of complete response "CR", very good
partial response "VPR", partial response "PR", stable disease "SD", or progressive disease "PD". Objective response (OR) is the sum of complete plus any partial response. I-131 MIBG scan was done 24 and 48 hours after IV injection of 0.5-1 mCi I-131 MIBG 5 days prior to starting chemo-therapy. Myocardial I-131 MIBG uptake in the anterior image of the whole body was graded according to the following scale: grade (0): no visible
uptake, grade (1): mild uptake, grade (2): moderate uptake, grade (3): prominent uptake.
Results: We found statistically significant correlation between I-131 MIBG myocardial uptake and patients outcome with P value <0.05. Eight
patients showed prominent (grade 3 uptake) and all the 8 patients showed
complete response to treatment and were alive at 24 months. 5 patients out of these 8 patients were stage III and 3 patients were stage IV neuroblastoma. On the other hand 9 patients showed no uptake(grade 0), 4 patients of them patients showed partial response to combined modality treatment, while three patients showed progressive disease and 2 patients showed stationary disease Fourteen patients (37%) showed moderate (grade 2) I-131 MIBG myocardial uptake, two patients them of showed complete response (CR), 10 patients showed partial response(PR) and two patients showed stationary disease (SD). All these fourteen patients were alive at the end of 24 months. Seven patients showed mild (grade 1) I-131 MIBG myocardial uptake. Five patients (71.4%) of them showed partial response
to treatment, one patient (14.2%) showed stationary disease(SD), and one patient (14.2 %) showed progressive disease(PD) with statistically significant correlation (P value <0.05 ) (Table 2) .Three patient of this group ( 42.8%) died because of their disease progression with statistically significant correlation with I-131 MIBG myocardial uptake.
Conclusion: We conclude that there is a correlation between I-131 MIBG myocardial uptake and patients outcome and survival, thus it can be used
as a prognostic factor for advanced cases of neuroblastoma.