1. An information processing system which supports a pathological diagnosis based on tissue sample image data obtained by imaging a body tissue, the system comprising: a pathological diagnosis apparatus comprising a processor configured to perform a pathological diagnosis based on a plurality of first regions of interest of the tissue sample image data and output a first pathological diagnosis result indicating positive or negative for a disease, the plurality of the first regions of interest being respective ones of partial regions of the tissue sample image data; and a pathologist terminal comprising a processor configured to receive input indicating a second pathological diagnosis result obtained by a pathological diagnosis performed by a pathologist based on the tissue sample image data, the second pathological diagnosis result indicating positive or negative for the disease, wherein the pathological diagnosis apparatus is further configured to: compare the first pathological diagnosis result and the second pathological diagnosis result and output a third result for the disease based on the comparison; when both the first pathological diagnosis result and the second pathological diagnosis result indicate positive, perform an image analysis of the tissue sample image data to calculate a positivity grade of disease based on the tissue sample image data, and output the third result indicating the positivity grade of disease; when both the first pathological diagnosis result and the second pathological diagnosis result indicate negative, output the third result indicating negative for the disease without performing the image analysis of the tissue sample image data to calculate the positivity grade of disease; when the first pathological diagnosis result indicates negative and the second pathological diagnosis result indicates positive, output the third result indicating one or more of the plurality of first regions of interest of the tissue sample image data each of which is determined as negative for disease by the pathological diagnosis apparatus; and when the first pathological diagnosis result indicates positive and the second pathological diagnosis result indicates negative, output the third result indicating one or more of the plurality of first regions of interest of the tissue sample image data each of which is determined as positive for disease by the pathological diagnosis apparatus.