COMPARISON OF CELL-PROLIFERATION IN BREAST-CARCINOMA USING IMAGE-ANALYSIS (KI-67) AND FLOW CYTOMETRIC SYSTEMS

Cellular proliferation has been implicated as an important predictor of biologic behavior in breast cancer. Cellular proliferation of 95 breast carcinomas was evaluated by comparing Ki-67 immunoreactivity in frozen sections quantitated by image analysis with S-phase and S + G2/M phase fraction determined by flow cytometry on nuclei extracted from fixed, paraffin-embedded sections (modified Hedley's technique). These parameters were correlated with traditional morphologic features of histologic grade, including mitotic count. Ki-67 immunoreactivity correlated with S-phase fraction determined by flow cytometry (r=.41, P=.001) and with S + G2/M phase fraction determined by flow cytometry (r=.29, P=.008). There was also a correlation between histologic grade and Ki-67 immunoreactivity (r=.30, P=.004) and between histologic grade and S-phase fraction (r=.42, P=.0001). Mitotic count correlated with Ki-67 immunoreactivity (r=.25, P=.015) and with S-phase fraction (r=.35, P=.001). Image and flow cytometric analysis systems provide comparable measurements of cellular proliferation; their measurements correlate with histologic grade and mitotic count in breast cancer.