IN-111 PENTETREOTIDE SCINTIGRAPHY IN PATIENTS WITH NEUROBLASTOMA - COMPARISON WITH I-131 MIBG, N-MYC ONCOGENE AMPLIFICATION, AND PATIENT OUTCOME

Objective: 1. To evaluate the relative efficacy of In-111 pentetreotid e and I-131 radioiodinated meta-idobenzyl guanidine (MIBG) for detecti on of primary and metastatic neuroblastoma. 2. To assess the prognosti c value of In-111 pentetreotide uptake. Methods and Materials: Seven I n-111 pentetreotide and seven I-131 MIBG scans were obtained in six pa tients with stage IV neuroblastoma and 1 with stage III ganglioneurobl astoma. Three scans were obtained at initial staging and four were obt ained during therapy. Correlation was made with concomitant computed t omography scans, bone scans, N-myc oncogene amplification, and clinica l outcome.Results: Primary tumor was present in six patients and had b een resected in 1. In-111 pentetreotide uptake was seen in two of six primary tumors, I-131 MIBG scan was positive in five of six. In-111 pe ntetreotide scan was positive in two of four patients with bone metast ases, I-131 MIBG scan was positive in three of four. Both showed liver metastases in one patient and did not show bone marrow metastases in another. Overall sensitivity for primary or metastatic disease was 57% (four of seven) for In-111 pentetreotide and 86% (six of seven) for M IBG. Correlation between N-myc oncogene and In-111 pentetreotide uptak e was seen in four of seven patients. In-111 pentetreotide uptake corr elated with the clinical outcome in six patients with more than 1 year follow-up. Two patients with negative In-111 pentetreotide scans had an unfavorable outcome. One patient died, and the other had local recu rrence 15 months after diagnosis. Four patients with a positive scan a re alive without disease on follow-up at 13-31 months after diagnosis. Conclusion: In-111 pentetreotide scintigraphy is less sensitive than I-131 MIBG for detecting active neuroblastoma. In-111 pentetreotide up take on scintigraphy may correlate with the prognosis. However, a larg er series of patients is needed for further evaluation.