The invention relates to the treatment of cancer. In particular the invention relates to an internal therapeutic product comprising: (i) an anti-cancer component selected from one or both of: a radionucleotide, a cytotoxic drug; and (ii) a silicon component selected from one or more of: resorbable silicon, biocompatible silicon, bioactive silicon, porous silicon, polycrystalline silicon, amorphous silicon, and bulk crystalline silicon, the internal therapeutic product being for the treatment of cancer.