Cancer Nanotheranostics, Volume 2 continues the discussion of the important work being done in this field of cancer nanotechnology. The contents of these two volumes are explained in detail as follows. In the first volume of Cancer Nanotheranostics, we discuss the role of different nanomaterials for cancer therapy including lipid-based nanomaterials, protein and peptide-based nanomaterials, polymer-based nanomaterials, metal-organic nanomaterials, porphyrin-based nanomaterials, metal-based nanomaterials, silica-based nanomaterials, exosome-based nanomaterials, and nano-antibodies.