Lymphocytotoxicity to tumor target cells and interference of serum factors or tumor antigen with lymphocytotoxicity in patients suffering from different stages of breast carcinoma.

The in vitro cytotoxicity of lymphocytes from patients suffering from breast carcinoma against autochthonous, allogeneic and established breast carcinoma cells was evaluated. Lymphocytotoxicity to breast carcinoma cells was observed in all stages of the disease. Control lymphocytes from healthy donors or patients suffering from other carcinoma are not cytotoxic for the breast carcinoma cell lines. A follow-up study of the cell mediated immune reactions before and after surgical removal of the breast carcinoma showed that the cytotoxic lymphocyte population which is demonstrated in the presence of the tumor disappears quickly after excision of the carcinoma. The non-reactivity of lymphocytes is not due to a general immune defect. Serum of the tumor bearers did not block the lymphocytotoxicity in early stage breast carcinoma; in metastatic disease inhibition occurred in more than half of the cases. Preincubation of lymphocytes with antigen preparations of allogeneic breast carcinoma cells did not inhibit the cytotoxicity to breast carcinoma cells whereas autologous serum preincubated with the antigen preparation diminished the lymphocyte reactivity to the target cells in some cases.