Lymphocyte subpopulations in mammary cancer after radiotherapy

B- and T-lymphocytes, identified by two methods of rosette-formation with sheep erythrocytes, fall to low levels within 1 week of the start of post-operative radiotherapy for cancer of the breast. Fifty-two such patients are compared with 34 age- and disease-matched patients treated by mastectomy alone. The B-lymphopenia reverts to normal levels by 10 months while the T-lymphopenia persists for at least 2 to 4 years