Does simple estimation of I-131-meta-iodobenzylguanidine uptake in patients with neural crest tumours correlate with clinical outcome?

A retrospective study was undertaken in six patients (three male and three female) with neural crest tumours who received therapeutic doses of I-131-m eta-iodobenzylguanidine (I-131-MIBG) (6.7-10.5 GBq). The age range of the p atients was 13-65 years (mean 36 years). Quantification of tumour uptake wa s obtained from images acquired with a large-field-of-view gamma camera on a single occasion between 2 and 10 days post-treatment. Tumour uptake was c alculated to be 0.1% and 3.2% of the administered dose, corresponding to up takes of 6.7-142.8 MBq. Tumour volume was assessed from computed tomography (CT) or magnetic resonance (MR) images and estimates of tumour dose made f rom the Medical Internal Radiation Dosimetry scheme (MIRD) tables. Estimate d doses were between 7 and 113 Gy. Most significantly, our findings indicat e that high tumour uptake did not always correlate with good clinical respo nse. ((C) 2001 Lippincott Williams & Wilkins).