Radioactive Microspheres for Selective Internal Radiation Therapy of Hepatocellular Carcinoma

Selective internal radiation therapy (SIRT) as one of the radiotherapeutic techniques has been widely used in the treatment of primary and metastatic liver cancer, for better avoiding radiation damage to normal tissues from external exposure. The radioactive microspheres used in SIRT should meet some special requirements closely associated with the type of radionuclides and the size and the property of the microsphere. This review focuses on the radioactive microspheres to elaborate the current challenges in the related fields, including simplification of the preparation of microspheres formed by different materials, visualization of the biodistribution of microspheres, and the suitability of different types of microspheres for repeated treatment. In this context, the major characteristics of three kinds of commercialized radioactive microspheres are compared, the advances in the radioactive microspheres achieved in recent years are summarized, and the future prospects of radioactive microspheres are discussed.