IMMUNOCYTOCHEMICAL DETECTION OF BREAST-CANCER CELLS - A COMPARISON OF3 ATTACHMENT FACTORS

The evaluation of contaminating breast cancer cells in hematopoietic g rafts is of considerable importance for monitoring the efficiency of p urging procedures. We report a comparison of three systems for the in vitro detection and enumeration of metastatic breast cancer cells. Bre ast cancer cells from established cell lines were mixed with Daudi cel ls at dilutions ranging from 1:10 to 1:1,000,000, and a predetermined number were fixed in defined areas on microscope slides coated with on e of the following attachment factors: (i) Cell-Tak(R) Cell and Tissue Adhesive, (ii) 0.1% solution of Poly-L-Lysine, or (iii) Gel-Line HTC Super Cured(R) slides. We employed a specificity-proven pancytokeratin antibody (A45-B/B3) and the alkaline phosphatase-antialkaline phospha tase (APAAP) staining technique. In multiple experiments, one breast c ancer cell in 1,000,000 Daudi cells could reliably be detected in the Cell-Tak and Gel-Line systems and 1 in 100,000 with the Poly-L-Lysine system. The observed number of seeded cells showed a highly significan t correlation with the number of cells seeded (p < 0.0001 in all cases ). Finally, we used the Cell-Tak method to evaluate clinical material from various sources: from patients with primary carcinomas of the bre ast, prechemotherapy, and during various chemotherapeutic regimens, as well as from patients with metastatic disease. The system consistentl y detected tumor cells in bone marrow samples from these patients. All peripheral blood samples from patients with metastatic disease tested positive at incidences ranging from 5 to 19/10(6) peripheral blood mo nonuclear cells. This is a simple and reliable technique that allows r apid screening of large cell numbers with high resolution of positive cells.