[Comparative analysis of immunoreactive indices in malignant and benign bone tumors]

The paper discusses the results of a study of immunologic surveillance in patients with bone tumors. T-lymphocyte deficiency was found in 21-32% of cases only, while all patients showed changes in the level of some T-cell subpopulations and their ratio. Patients with malignant tumors (mostly osteosarcoma) revealed a lowered response to PHA and a high frequency of sensitization to tumor antigens. In those cases, serum, blood--circulating T-cells and tumor--infiltrating lymphocytes showed a suppressor activity. A moderately decreased response to PHA, a low frequency of sensitization to tumor antigens and a stimulating activity in serum, blood--circulating T-cells and lymphocytes were registered in cases of benign tumors (mainly giant cell tumors). Suppressor activity of blood T-lymphocytes was matched by a high level of TG cells, while stimulating effect--by a low one.