DNA FLOW-CYTOMETRY AND BREAST-CANCER

Measurement of cellular DNA content by flow cytometry is capable of detecting aneuploid stemlines, and also of giving an indication of tumor proliferation kinetics by approximating the percentage of cells in S-phase of the replicative cycle. Because it can be applied both to fresh frozen material submitted for steroid hormone receptor analysis and to fixed paraffin-embedded blocks, it is particularly well suited to the study of breast cancer. Despite being a relatively straightforward test which is now widely used in the risk assessment of patients with early breast cancer, in common with many other prognostic markers its precise clinical role remains uncertain. An extensive body bf published data has appeared in the last few years, but the results often appear to be inconclusive or contradictory. In order to define the prognostic significance of DNA cytometry in malignant diseases of the breast, large bowel, bladder, prostate, and hematopoietic system, and to clarify some of the technical issues related to clinical laboratory standards and quality controls, a DNA Cytometry Consensus Conference was held in Prout's Neck, Maine, on October 1-4, 1992. This meeting was sponsored by the NCI, the International Society for Analytical Cytology, and industry. The significance of the meeting's conclusions for clinical breast cancer are discussed here. The consensus statement regarding the clinical utility of DNA cytometry in breast cancer, and the Guidelines for the Implementation of Clinical DNA Cytometry which were generated at this meeting, also appear in this issue of Breast Cancer Research and Treatment.