A device and method of treating proliferative disorders such as pancreatic cancer are described. Devices comprise an expandable mesh with two axial wings that seal against the inside of an enclosing blood vessel, creating an enclosed diffusion volume in the area subtended by the wings while permitting normal flow in the blood vessel through the ends of the mesh. A coaxial lumen provides for a guide wire, treatment drug tube, one or more flexible hypotubes and optionally electrical wires. The diffusion volume is set by the angle subtended by the wings causing the drug delivery to be radically directed toward a targeted tumor. Iontophoresis and electroporation electrodes on the mesh are used to directionally drive the drug through adjacent tissue and to temporarily increase the permeability of tissue through which the drug flows.