1. A radiation treatment planning system for use in effecting radiation therapy of a pre-selected anatomical portion of an animal body, comprising: an imaging device configured to generate image data corresponding to the anatomical portion; a positioning device configured to position the imaging device within the pre-selected anatomical portion, wherein the positioning device includes a template; a radiation delivery device configured to deliver at least one energy emitting source through at least one of a plurality of hollow needles inserted into the anatomical portion with the guidance of the template; a processor configured to generate a radiation treatment plan for effecting the radiation therapy, wherein the processor is configured to; convert the image data into a three-dimensional image of the anatomical portion; designate multiple sampling points in the three-dimensional image; calculate a radiation dose distribution for at least one sampling point, based on at least one of an actual number and position of at least one of the plurality of hollow needles, an actual position of the at least one energy emitting source within the at least one of the plurality of hollow needles, or an actual dwell time of the at least one energy emitting source at the position; and determine, based on at least one solution to an objective function, a radiation treatment plan reflecting a radiation dose via the at least one of the plurality of hollow needles, wherein a number of operations for calculating the at least one solution is independent of the number of sampling points.