A method and apparatus wherein an application of energy is limited to a specific diseased portion of body tissue (target tissue) for the purpose of localizing the treatment to the target tissue and avoiding an adverse effect on surrounding tissue. In one embodiment, access to the target tissue is provided by inserting an energy transmission device through a needle for delivery of the energy into the target tissue. Guidance of the needle is alternatively enhanced through use of an image guidance device. Alternatively, in addition the localized treatment is further controlled by use of an energy-concentrating/enhancement agent and/or photosensitizing/photoselective agent, chromophore dye and viscous substance to cause selective interaction with a specific wavelength of an energy source. The treatment can be further controlled and localized by improving the accuracy and positioning of the delivery device into the target tissue using imaging guidance.