1. A medical image diagnosing support method, comprising: a site region extracting step of obtaining, by a medical image diagnosing apparatus, a tomographic image, and extracting a predetermined site region from the obtained tomographic image; a first region extracting step of extracting a first lesion candidate region from the site region in the tomographic image based on pixel values of the site region extracted in the predetermined site region extracting step; a second region extracting step of extracting a second lesion candidate region from the site region in the tomographic image based on a distribution of pixel values of the site region extracted in the predetermined site region extracting step; and a region correcting step of extracting as a pulmonary emphysema a corrected lesion candidate region where the first lesion candidate region overlaps with the second lesion candidate region.