1. A classification apparatus for pathologic diagnosis of medical image, comprising: a processor; and a non-transitory storage medium having program instructions stored thereon, execution of which by the processor causes the classification apparatus to provide functions of: a feature extraction unit configured to extract feature data for an input image using a feature extraction variable; a feature vector transformation unit configured to transform the extracted feature data into a feature vector using a vector transform variable; and a vector classification unit configured to classify the feature vector using a classification variable, and to output results of the classification of pathologic diagnosis for the input image; wherein the feature extraction unit, the feature vector transformation unit and the vector classification unit are trained based on a first tagged image having a first tag indicative of presence or absence of a lesion and pathologic diagnosis information, a second tagged image having a first tag as well as a second tag indicative of location information of the lesion, and an image having no tag, and wherein the feature extraction variable is trained based on the second tagged image; the transform variable is trained based on at least one of the first tagged image, the second tagged image and the image having no tag; and the classification variable is trained based on at least one of the first tagged image and the second tagged image.