INTRAOPERATIVE SEARCH FOR NEUROBLASTOMA BY MIBG AND RADIOGUIDED SURGERY WITH THE GAMMA-DETECTOR

Administration of a tumour-seeking compound labeled with a low-energy isotope and intraoperative screening with the gamma probe (radioguided surgery, RCS) could be useful in reoperations for advanced neuroblast oma when the normal anatomy is altered. A pilot study was performed to test the feasibility of this technique. Five patients underwent six r elaparotomies for recurrent stage III or IV neuroblastoma. All had bee n treated with intensive chemotherapy and/or metaiodobenzylguanidine ( MIBG)-I-131 with or without hyperbaric oxygen. Reoperation was perform ed to achieve near-total (greater than 95%) excision. In all instances , active tumour was seen on the preoperative MIBG scan. Before the ope ration, a tracer dose of MIBG-I-123 was given. At laparotomy, a search was made with the gamma probe for areas of increased activity. The ga mma probe correctly identified active neuroblastoma tissue that was se en on the preoperative MIBG scan. There appeared to be a relationship between intensity of radioactivity and degree of maturation on histolo gic examination. This pilot study shows that RCS with MIBG and intraop erative use of the gamma probe is able to identify recurrent neuroblas toma. Whether this method is able to detect occult tumour and whether RGS will result in better outcome are the subjects of ongoing research . (C) 1997 Wiley-Liss, Inc.