Clinical and prognostic usefulness of immunohistochemical determination of Ki67 in breast cancer

Abstract The relation between the cell proliferation marker detected by Ki67 monoclonal antibody and tumour size, node involvement, menopausal status, nuclear oestrogen receptors and disease-free survival has been analysed in 236 consecutive breast cancer patients who presented from December 1986 to October 1989. The patients had a median age of 56 years (26–82) and were followed for a median of 34 months (7–51). Ki67 antigen levels were lower in small tumors and when nuclear oestrogen receptors were positive, but did not correlate with nodal involvement. Preliminary data suggest disease-free survival is longer when Ki67 antigen levels are low.