Needle array assembly and method for delivering therapeutic agents

A device for simultaneously delivering a plurality of agents to a plurality of spatially defined locations of a selected region of a solid tumor on a delivery axis, said device comprising: a plurality of needles arranged in a matrix and configured to deliver the plurality of agents separately at said defined locations in the solid tumor such that, when the agents are administered, they are located in regions that are approximately columnar in shape, coaxial with regarding the axis of administration; and a plurality of reservoirs, each in fluid communication with a respective one of said plurality of needles, wherein each reservoir may comprise a different agent.