Blood lymphocyte subpopulations in breast cancer patients following post-operative adjuvant chemotherapy or radiotherapy.

The peripheral lymphocyte population was examined in sixty-five randomized breast cancer patients before and after post-operative adjuvant cyclic chemotherapy or local radiation therapy. During 10 months of chemotherapy total lymphocyte and T cell counts were reduced to 70% and non-T cells to about 50% of pretreatment values. The population of T cells was unaltered whereas the proportion of non-T cells was significantly reduced at the end of the period. Immediately after radiotherapy total lymphocyte and T cell counts were reduced to 30%, and non-T cells to 15% of pretreatment values. During 10 months' observation total lymphocyte and T cell counts increased to 70%, and non-T cells to 50--60% of pretreatment values.