A
data processing method applied to radiotherapy, and a related apparatus. The method comprises: acquiring a plurality of two-dimensional images corresponding to an object to be subjected to radiotherapy; in response to an organ selection operation of an operator, displaying, on a three-dimensional delineation interface, a three-dimensional
organ region corresponding to a selected organ; in response to a three-dimensional delineation operation of the operator on the three-dimensional delineation interface, determining a three-dimensional delineation region in the three-dimensional
organ region which corresponds to the three-dimensional delineation operation; and on the basis of the plurality of two-dimensional images and the three-dimensional delineation region, determining a plurality of two-dimensional delineation regions of the three-dimensional delineation region which correspond to the plurality of two-dimensional images on a one-to-one basis, wherein the plurality of two-dimensional delineation regions are used for performing radiotherapy on said object. By means of the method, an operator first performs three-dimensional delineation on a three-dimensional
organ region, and then inversely parses onto a plurality of two-dimensional images a three-dimensional delineation region corresponding to the three-dimensional delineation, and thus a plurality of two-dimensional delineation regions can be obtained by means of one instance of three-dimensional delineation, thereby improving the efficiency of delineation while ensuring the accuracy of delineation.