Radionuclide therapy of adrenal tumors

Abstract

Adrenal tumors arising from chromaffin cells will often accumulate radiolabeled metaiodobenzylguanidine (MIBG) and thus are amenable to therapy with I-131 MIBG. More recently, therapy studies have targeted the somatostatin receptors using Lu-177 or Y-90 radiolabeled somatostatin analogs. Because pheochromocytoma (PHEO)/paraganglioma (PGL) and neuroblastoma (NB), which often arise from the adrenals, express these receptors, clinical trials have been performed with these reagents. We will review the experience using radionuclide therapy for targeting PHEO/PGL and NBs.

Pheochromocytoma and paraganglioma: Diagnosis, genetics, management, and treatment

“…Before the scan and for the duration of therapy, the patient should be taken off medications that can block MIBG uptake such as labetalol, tricyclic antidepressants, and certain calcium antagonists. 5,114,126,206,207 The therapy is based on the emission of beta particles once the radioactive compound has been taken up into tumor cells, leading to their destruction. 206 Broadly, two strategies are being evaluated with regards to MIBG therapy.…”

“…5,114,126,206,207 The therapy is based on the emission of beta particles once the radioactive compound has been taken up into tumor cells, leading to their destruction. 206 Broadly, two strategies are being evaluated with regards to MIBG therapy. In some trials and studies, 131 I-MIBG therapy is given in small doses over a longer period.…”

“…Doses usually range from 100-300 milliCuries (mCi) and are given once every 3-4 months for up to an approximately 1000 mCi dose total, although there are no strictly established guidelines on maximum cumulative dosage or repeated doses. 206 A retrospective analysis of 116 patients who received mean single doses of 158 mCi for a range of 1-11 treatments, resulting in cumulative doses ranging from 96-2322 mCi, reported improved symptoms in 76% of patients, biochemical responses in 45%, and tumor responses in 30%; 5 patients reported complete tumor and biochemical responses for 16-58 months. Side effects were generally mild and reported in 41% of patients; only one patient suffered extreme toxicities and died from bone marrow asplasia.…”

“…208 However, some centers have experimented with giving extremely large one-time doses of MIBG, followed by stem cell infusion to replace bone marrow. 206 In one such study, 49 patients were treated with single doses of 492-1160 mCi, with 15 patients receiving multiple doses, for total doses of 492-3191 mCi. Fifty-seven percent of patients had a complete, partial, or minor response, and an additional 8% achieved stable disease for at least one year.…”

Therapeutic radionuclides in nuclear medicine: current and future prospects

“…In the last twenty years, radionuclide therapy has been widely used in various clinical malignant and pain management applications (Hoefnagel, 1991;Nakabeppu and Nakajo, 1994;vande Streek et al, 1994;Forrer et al, 2006;Williams et al, 2008;Lambert et al, 2010;Nestor, 2010;Chiacchio et al, 2011;Ersahin et al, 2011;Carrasquillo et al, 2012;Ezziddin et al, 2012;Gabriel, 2012;Gulenchyn et al, 2012;Dash et al, 2013;Sainz-Esteban and Baum, 2013). Radionuclide therapy has the advantage of delivering a highly concentrated absorbed dose to the targeted tumour while sparing the surrounding normal tissues.…”