Identification and importance of lymphocyte subpopulations in the regional lymph nodes of breast cancer patients.

To determine whether the presence of metastatic cancer cells in lymph nodes is accompanied by changes in lymphocyte subpopulations identified in tissue sections, the authors studied metastatic and nonmetastatic lymph nodes from eight patients with breast cancer and lymph nodes of three control patients. In all metastatic lymph nodes, T cells were seen in close contact with infiltrating cancer cells; B cells tended to accumulate focally, apart from cancer cell nests. In both metastatic and nonmetastatic lymph nodes from breast cancer patients, the fractional areas occupied by the T4 (helper) and T8 (suppressor/cytotoxic) lymphocytes were comparable. The B-cell fractional area was significantly (p less than 0.01) greater in nonmetastatic than in metastatic nodes. The fractional area occupied by the T8 lymphocytes in the breast cancer patients was significantly (p less than 0.01) greater than in the normal lymph nodes, but no difference was noted in the fractional area occupied by the T4 cells. These findings indicate that all lymph nodes in breast cancer patients are characteristically increased in suppressor/cytotoxic lymphocytes, and the presence of metastatic cancer cells in the nodes is manifested by a depletion of B lymphocytes.