TY - JOUR T1 - Addition of <sup>131</sup>I-MIBG to PRRT (<sup>90</sup>Y-DOTATOC) for Personalized Treatment of Selected Patients with Neuroendocrine Tumors JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1274 LP - 1277 DO - 10.2967/jnumed.120.254987 VL - 62 IS - 9 AU - David L. Bushnell AU - Kellie L. Bodeker AU - Thomas M. O’Dorisio AU - Mark T. Madsen AU - Yusuf Menda AU - Stephen Graves AU - Gideon K.D. Zamba AU - M. Sue O’Dorisio Y1 - 2021/09/01 UR - http://jnm.snmjournals.org/content/62/9/1274.abstract N2 - Peptide receptor radionuclide therapy (PRRT) is an effective treatment for metastatic neuroendocrine tumors. Delivering a sufficient tumor radiation dose remains challenging because of critical-organ dose limitations. Adding 131I-metaiodobenzylguanidine (131I-MIBG) to PRRT may be advantageous in this regard. Methods: A phase 1 clinical trial was initiated for patients with nonoperable progressive neuroendocrine tumors using a combination of 90Y-DOTATOC plus 131I-MIBG. Treatment cohorts were defined by radiation dose limits to the kidneys and the bone marrow. Subject-specific dosimetry was used to determine the administered activity levels. Results: The first cohort treated subjects to a dose limit of 1,900 cGy to the kidneys and 150 cGy to the marrow. No dose-limiting toxicities were observed. Tumor dosimetry estimates demonstrated an expected dose increase of 34%–83% using combination therapy as opposed to 90Y-DOTATOC PRRT alone. Conclusion: These findings demonstrate the feasibility of using organ dose for a phase 1 escalation design and suggest the safety of using 90Y-DOTATOC and 131I-MIBG. ER -