FLOW CYTOMETRIC ENUMERATION AND KINETIC-ANALYSIS OF INFLAMMATORY CELL-POPULATIONS IN BREAST CARCINOMAS

Inflammatory cell populations were quantitated in 76 consecutive mecha nically dissociated clinical breast carcinoma specimens using multipar ameter, two-color (PI-cytokeratin/FITC, PI-LCA/FITC) flow cytometric a nalysis. The percent LCA-positive events varied from 1.3-62.5% (mean = 11%) and correlated with degree of histologic inflammatory cell infil trate (mild-5.8% LCA + events vs. marked-35.9%. LCA + events, P < 0.00 1), abnormal DNA content (diploid range - 4.6% LCA + events vs. aneupl oid - 13.3% LCA + events, P = 0.003) and poor tumor differentiation (w ell-moderate - 6.5% LCA + events vs. poor - 19.9% LCA + events, P = 0. 001). Synthesis phase fractions in LCA-positive populations were unifo rmly less than the corresponding cytokeratin (CK)-positive cells (mean LCA + SPF = 4.4% vs. mean CK + SPF = 15.5%) and varied from 3-11%. Pr oliferation among inflammatory populations did not correlate statistic ally with the total percent of LCA or CK-positive events, nor with the SPF in epithelial populations. However, proliferative activity of inf lammatory components was greater in tumors with predominately intratum oral, vs. peritumoral, inflammatory cell distribution (4.6% vs. 3.3% P = 0.03) and in,tumors with greater numbers.of large, 'transformed' ly mphocytes (few = 3.25% vs. many = 6.5% LCA + SPF, P = 0.001). We concl ude multiparameter flow cytometric analysis of mechanically-dissociate d breast tumors is representative of tumor infiltrating lymphoid popul ations in breast tumors and provides a potentially useful means of stu dying biologically relevant tumor-host interactions.