Table 1.
Characteristics of commercially available 90Y-microspheres for TARE
| SIR-Spheresa | TheraSphereb | |
|---|---|---|
| Isotope 90Y | Attached to the surface | Incorporated into the glass matrix |
| Half-life (h) | 64.1 | 64.1 |
| Microsphere material | Resin | Glass |
| Microsphere diameter (μm) | 20–60 | 20–30 |
| Average size (μm) | 32.5 | 25 |
| Approximate activity per microsphere (Bq) | 50 | 2,500 |
| Number of microspheres per 3 GBq | 40×106–80×106 | 1.2×106 |
| Specific gravity (g/mL) | 1.6 | 3.6 |
| Activity per commercially available vial (GBq) | 3 (can be divided) | 3, 5, 7, 10, 15, 20 |
| Activity calculation | Compartmental MIRD macrodosimetry or empirical formula based on liver volume and tumor volume | Non-compartmental MIRD macrodosimetry |
| Estimated dose to the central vein area (Gy) in the Monte Carlo simulationc | 59 | 58 |
| Embolic effect | Moderate | Mild |
| Contrast agent injection | During infusion | None |
| Indication | USA (FDA PMA): Colorectal liver metastases | USA (FDA HDE): Hepatocellular carcinoma |
Notes: Data from Sangro et al.25
a
Sirtex Medical, North Sydney, Australia;
b
BTG International Canada Inc., Ottawa, ON, Canada;
c
Gulec SA, Sztejnberg ML, Siegel JA, Jevremovic T, Stabin M. Hepatic structural dosimetry in (90)Y microsphere treatment: a Monte Carlo modeling approach based on lobular microanatomy. J Nucl Med. 2010;51(2):301–310. © by the Society of Nuclear Medicine and Molecular Imaging, Inc.
Abbreviations: 90Y, yttrium-90; TARE, transarterial radioembolization; MIRD, Medical Internal Radiation Dosimetry; FDA, Food and Drug Administration; PMA, premarket approval; HDE, Humanitarian Device Exemption.