1. An image diagnosis supporting apparatus comprising: a slice image group acquisition device which acquires a first slice image group and a second slice image group with different photographing opportunities or modalities; a lesion area extraction device which extracts a first lesion area from the first slice image group and extracts a second lesion area corresponding to the first lesion area from the second slice image group; a reference slice image determination device which determines a first reference slice image of the first slice image group based on the extracted first lesion area and determines a second reference slice image of the second slice image group based on the extracted second lesion area; a slice image selection device which selects slice images for comparative image interpretation from each of the first slice image group and the second slice image group, the slice images being the same distance away from the determined first reference slice image and the second reference slice image respectively; and an output device which outputs the selected slice images so that the slice images can be compared and interpreted.