Acute changes in blood pressure in patients with neuroblastoma treated with 131I-metaiodobenzylguanidine (MIBG)

Background Iodine-131-metaiodobenzylguanidine (131I-MIBG) provides targeted radiotherapy for children with neuroblastoma. The aim of our study was to evaluate systematically the acute effects of 131I-MIBG on blood pressure in patients with neuroblastoma and to identify possible predictors of hypertension. Procedure We conducted a retrospective chart review of neuroblastoma patients who were treated with 131I-MIBG between January 1, 1999 and June 1, 2012 at the University of California, San Francisco. Clinical data for 172 patients with neuroblastoma, receiving 218 administrations of 131I-MIBG, were collected. The primary endpoint was development of systolic blood pressure above the 95th percentile for age. Logistic regression with generalized estimating equations to account for multiple administrations in some subjects was used to identify bivariate and multivariate predictors of hypertension. Results Of the 218 administrations of 131I-MIBG, 112 (51.3%) were associated with at least one episode of systolic hypertension during or after the 131I-MIBG infusion. The majority of these acute elevations in blood pressure resolved within 48 hours of the infusion. Only six administrations in five patients required nifedipine administration to lower blood pressure. Younger age (P = 0.012), lower eGFR (P = 0.047), and elevated blood pressure measurements immediately before infusion began (P = 0.010) were all independently associated with risk of treatment-associated hypertension. Conclusions Acute elevations in blood pressure are common after therapeutic doses of 131I-MIBG. Elevations in blood pressure typically occur only within the first 48 hours after 131I-MIBG administration. Blood pressure monitoring during this period of risk is recommended. Pediatr Blood Cancer 2013;60:1424–1430. © 2013 Wiley Periodicals, Inc.