A FLOW CYTOMETRIC STUDY ON GIANT-CELL TUMOR OF BONE

Objective. Giant cell tumor of bone (GCT) is a comparatively common bo ne tumor in Chinese. Though GCT is generally considered as a benign tu mor, it can pursue an aggressive course. The present study attempts to clarify whether the flow cytometric study can be an useful tool for p rognosis of GCT patients. Methods. DNA content and cell cycle studies on 96 pathologically confirmed GCT specimens and anti-GCT monoclonal a ntibody (GCF-5 McAb) labeling study on 30 GCTs were made by flow cytom etry. Results. 29 GCTs (30.2%) exhibited aneuploid and 67 (69.8%) dipl oid. Of 71 primary tumors, 16 (22.5%) exhibited aneuploid. The average DNA index was 0.97+0.15, and the average S, G(2)/M phase cells 15.235.15%. Of 25 recurrent tumors, 13 (52%) were aneuploid, with an averag e DI of 1.08+0.17. The average S, G(2)/M phase cells was 19.563-7.12%. Between the primary and recurrent tumor groups, there was significant statistical difference both in S, G(2)/M phase cell percentage (P<0.0 5) and DNA content (P<0.01). There was no significant difference betwe en Jaffe's grade I and grade II groups in DNA content or in S, G(2)/M phase cell percentage. GCF-5 McAb could combine with almost all cells of S, G(2)/M phase and part of the cells in G(0)/G(1) phase. Significa nt relationship existed (r=0.468, P<0.05) between the percentages of S , G(2)/M phase cells and GCF-5 positive cells. Between the primary and the recurrent tumor groups, there was a significant difference in the percentage of both S, G(2)/M phase cells and GCF-5 positive cells. Co nclusion. Apparently flow cytometric study is of value in the evaluati on of the biological behavior of GCT as well as the prognosis of the p atients.