Differential Diagnosis of Cytokeratin “Dots”
By Rodney T. Miller, M.D., Director of Immunohistochemistry In addition to evaluating the presence or absence of immunoreactivity per se, identification of a particular pattern of immunoreactivity is important, and can provide significant diagnostic information. One such pattern is perinuclear immunoreactivity, usually in the form of intracytoplasmic perinuclear dots or globs. This month, we direct our attention to the