Ki67, a nuclear protein presents in cells that is usually associated
with tumor cell proliferation. Therefore, physical quantification of Ki67 is a direct
measure cell proliferation activity. Immunohistochemical staining is known to be
an effective method of assessing the proportion of tumor cells. Currently, there
are various techniques for counting Ki67 in different types of cancer. This paper
provides an overview of recent scoring methods of Ki67, which includes ‘eyeballing’ estimation, vision counting with a microscope or viewer software,
manual counting of the camera-captured or digital image and automated
counting.