Feasibility and advantage of adding 131I-MIBG to 90Y-DOTATOC for treatment of patients with advanced stage neuroendocrine tumors

EJNMMI Research

Table 2 Tumor dose and administered activity results for the addition of ¹³¹ I-MIBG to ⁹⁰ Y-DOTATOC

Subject	MIBG vs. pentetreotide image pattern for metastases	Maximum activity (GBq)⁹⁰Y-DOTA alone (over multiple cycles)	Optimum percentage of max⁹⁰Y-DOTA activity to be given when adding MIBG	Activity (GBq) of¹³¹I-MIBG that can be added without exceeding limits (over multiple cycles)	Tumor dose (cGy):⁹⁰Y-DOTA given alone	Tumor dose (cGy):⁹⁰Y-DOTA + ¹³¹I-MIBG
1	Concordant	13.5	72	32.2	1,623	7,618
2	All tumors MIBG negative
3	All tumors MIBG negative
4	Discordant	11.1	88	29.8	3,317	11,119
5	All tumors MIBG negative
6	Discordant	14.4	16	42.8	10,330	45,737
7	Discordant	19.8	100	0.0	14,068	14,068
8	Discordant	4.9	75	33.3	1,006	2,499
9	Concordant	7.2	76	45.0	729	2,829
10	All tumors MIBG negative
Calculated using average dosimetry results from the literature^a	N/A	10.7	85	36.4	4,685	14,555

Total renal limit, 23 Gy; total marrow limit, 3 Gy. N/A, not applicable. ^aResults in this row were calculated using average dose values for the marrow, kidneys, and NETs from the literature.