A system and method for planning volumetric treatment by percutaneous needle procedures obtains a volumetric image data set of a subject including an identifiable region requiring treatment. An effective treatment volume is defined relative to the needle position for at least one needle carrying a treatment applicator. One or more proposed inserted needle position is defined such that a effective treatment volume corresponding to the one or more proposed inserted needle position provides coverage of the region requiring treatment. The effective treatment volume for one or more needles can then be visualized in the context of slices of 3D image data. One or more entry point and corresponding virtual target are then defined relative to a frame of reference of the volumetric image data set for use in navigation of the at least one needle to the corresponding proposed inserted needle position.