Role of radio-iodinated meta-iodo benzyl guanidine in assessment of children with neuroblastoma at NEMROCK.

BACKGROUND: For more than ten years. MIBG has been successfully used in diagnosis and staging of children with neuroblastoma.

AIM OF THE STUDY: Identify the role of 131I MIBG in the assessment of neuroblastoma and correlate its findings with other non-invasive tests.

PATIENTS AND METHODS: Twenty eight patients with neuroblastoma attending the Pediatric Oncology Unit, Kasr El-Aini Center of Radiation Oncology and Nuclear Medicine (NEMROCK), Cairo University, over a period of 5 years (2002-2006) were assessed by MIBG scanning. The age of patients ranged from 40 days to 12 years with a mean of 4.7 years +/- 1.1. They were 16 boys and 12 girls with a M:F ratio of 1:3, none was stage I and II, 7 patients (25%) were stage III and 21 patients (75%) were stage IV (Evan's staging system). Clinically, 24 patients (85.7%) presented with an abdominal mass, and 3 patients (10.7%) with a mediastinal mass. Metastases were present in the bone marrow in 11 children (39.3%), lymph nodes in 5 (17.9%), CNS in 4 (14.3%), liver in 2 (7.1%), soft tissues in 3 (10.7%), lungs and pleura in 1 (3.6%), brain in 1 (3.6%), and testis in 1 patient (3.8%).

RESULTS: 131I MIBG could accurately diagnose local and distant neuroblastoma lesions in 23 patients with a sensitivity of 82.2%. High levels of VMA correlated with no cardiac uptake in the first 24 hours in 7/8 patients with a sensitivity of 87.5%. On the other hand, low VMA levels were associated with cardiac uptake of (131)I MIBG in 3/4 patients with a specificity of 75%, a PPV of 88% and NPV of 86.7%. (131)I MIBG scintigraphy and bone marrow aspiration agreed on detecting neuroblastoma lesions in 24 /28 patients (85.7%) p<0.01, with a sensitivity of 59.5%, specificity of 96.6%. PPV of 89.3%, and NPV of 83.2%.

CONCLUSION: (131)I MIBG scintigraphy, in a dose of 2 mci can be used with 87.5% accuracy in the diagnosis and follow-up of Children with neuroblastoma.