Neurokinin-1 (NK-1) receptor-binding agent delivery conjugates, compositions comprising NK-1 receptor-binding agent delivery conjugates, and methods for making and administering NK-1 receptor-binding agent delivery conjugates are provided. A conjugate may include an NK-1 receptor-binding moiety, a linker group containing at least one linker selected from the group of a releasable linker and a spacer linker, and an active agent linked to the linker group. The active agent may be selected from the group of fluorophore-containing compounds, radionuclide-containing compounds, and therapeutic agents for treatment of tumor cells characterized by over-expression of the NK-1 receptor.
