Low-dose (123)I-metaiodobenzylguanidine Diagnostic Scan is Inferior to (131)I-metaiodobenzylguanidine Posttreatment Scan in Detection of Malignant Pheochromocytoma and Paraganglioma
Overview
Authors
Affiliations
Objective: We assessed the lesion detectability of low-dose diagnostic (123)I-metaiodobenzylguanidine (MIBG) whole-body scans obtained at 6 and 24 h compared with posttreatment (131)I-MIBG whole-body scans in malignant pheochromocytoma and paraganglioma.
Methods: Scintigrams obtained in 15 patients with malignant pheochromocytoma and paraganglioma were retrospectively analyzed. Diagnostic scans were performed with 111 MBq of (123)I-MIBG. Therapeutic doses of (131)I-MIBG (5.55-7.40 GBq) were administrated and whole-body scans were obtained at 2-5 days after (131)I-MIBG administrations. We compared the number of lesions and the lesion-to-referent count ratios at 6 and 24 h of (123)I-MIBG and at 2-5 days of (131)I-MIBG.
Results: In comparison with the 6-h images of (123)I-MIBG, the 24-h images of (123)I-MIBG could detect more lesions in eight patients. Posttreatment (131)I-MIBG scans revealed new lesions in eight patients compared with the 24-h images of (123)I-MIBG. The lesion-to-referent count ratios at 6 and 24 h of (123)I-MIBG and at 3 days of (131)I-MIBG were increasing at later scanning time. There were significant differences in the lesion-to-referent count ratios between 6 and 24 h of (123)I-MIBG (P = 0.031), 6 h of (123)I-MIBG and 3 days of (131)I-MIBG (P = 0.020), and 24 h of (123)I-MIBG and 3 days of (131)I-MIBG (P = 0.018).
Conclusion: Low-dose diagnostic (123)I-MIBG whole-body scan is inferior to posttreatment (131)I-MIBG whole-body scan in malignant pheochromocytoma and paraganglioma. Considering the scan timing of (123)I-MIBG, 6-h images might have no superiority compared with 24-h images.
Takenaka J, Watanabe S, Abe T, Takeuchi S, Hirata K, Kimura R Pharmaceuticals (Basel). 2025; 18(2).
PMID: 40005979 PMC: 11858449. DOI: 10.3390/ph18020165.
Navigating new horizons: Prospects of NET-targeted radiopharmaceuticals in precision medicine.
Higuchi T, Chen X, Werner R Theranostics. 2024; 14(8):3178-3192.
PMID: 38855189 PMC: 11155404. DOI: 10.7150/thno.96743.
Wakabayashi H, Kayano D, Inaki A, Araki R, Kuroda R, Akatani N Diagnostics (Basel). 2020; 10(9).
PMID: 32887257 PMC: 7555271. DOI: 10.3390/diagnostics10090663.
Pheochromocytoma: implications in tumorigenesis and the actual management.
Shah U, Giubellino A, Pacak K Minerva Endocrinol. 2012; 37(2):141-56.
PMID: 22691888 PMC: 3409463.
Tissue distribution studies of protein therapeutics using molecular probes: molecular imaging.
Williams S AAPS J. 2012; 14(3):389-99.
PMID: 22467336 PMC: 3385809. DOI: 10.1208/s12248-012-9348-3.