Effect of postoperative radiotherapy in breast carcinoma on peripheral blood lymphocytes

In 60 women with breast carcinoma treated by radical mastectomy followed by X-ray treatment the effect of radiotherapy on the absolute values of different subpopulations of lymphoid cells in the peripheral blood was investigated. In evaluating the effect of radiotherapy on the system of lymphoid cells the technique of rosette tests was used, with the rosette test E applied for determination of lymphocytes T, the EAC test used for determining lymphocytes B, and the Esub(act) test for Tsub(active) lymphocytes. On the basis of the obtained results it is concluded that postoperative radiotherapy in breast carcinoma causes lymphopenia T due, in the first place, to a fall in the number of cells forming active rosettes E. The participation of disturbances in the subpopulation of lymphocytes B is less evident. Disturbances in all lymphoid cells tested developed already at the time of radiotherapy reaching a maximum value immediately after its end and persisting for at least 12 months. The degree of postradiation damage to the lymphocyte system increases with increasing dose of radiation applied and when the thymus is included into the irradiated area. (author)