Due to the increased permeability and retention typical for the tumor, as well as the presence of specific receptors (Gp60, SPARC, FcRn) whose expression levels are increased in some cancers [45,46,56,57,58,59,60], albumin-binding constructs have great potential in cancer diagnosis and theranostics [42,44,61,62,63,64]. The gene discussed is SPARC; the disease is cancer.