Animal-based radiation absorbed dose evaluation of holmium-166 labeled hydroxyapatite particulates in liver malignancies.

OBJECTIVES

Liver malignancies are among the most prevalent causes of cancer-related deaths worldwide. Intra-arterial administration of particulates labeled with beta-emitting radionuclides is one of the non-surgical promising modalities for the treatment of liver cancer.

METHODS

In this work, the radiation absorbed dose of 166Ho-hydroxyapatite (166Ho-HA) radiopharmaceutical was estimated for adult men based on biodistribution data in normal Wistar rats. The MIRD dose calculation method and the Sparks and Aydogan methodology were applied.

RESULTS

The results show that more than 84% of the absorbed dose is localized in liver tissue (7.35 mGy MBq-1). Also, radiation absorbed doses of 166Ho-HA for red bone marrow, osteogenic cells, and spleen tissues were estimated to be about 0.18, 0.38, and 0.24 mGy MBq-1, respectively. The maximum administrated activity was obtained at 87.5 MBq kg-1 of body weight with an effective dose of 0.39 mSv MBq-1. The maximum tolerable dose (MTD) for liver tissue was 6.13 GBq (165.56 mCi).

CONCLUSION

This study indicated that 166Ho-HA can provide an impressive dose for liver cancer malignancies with an insignificant dose to healthy tissues.