Assessment of host immune response in breast cancer patients.

Cell-mediated immune status of breast cancer patients was evaluated by percentage of T gamma cells, natural killer (NK) activity, and the augmentation of NK cells by interferon. The patients with breast cancer did not show impaired cell-mediated immune responses until they were in the late stage of cancer. Sixty-one patients with breast cancer revealed higher proportions of T gamma cells measured by a new method utilizing microplate compared with those of 50 healthy subjects. Reduced NK activity was seen in the patients with stage III or IV breast cancer. Natural cytotoxicity against K-562 target cells was strongly augmentated by treatment with interferon in vitro for 2 hr, both in the patients with breast cancer and in healthy donors, except for far advanced breast cancer patients. A negative correlation between the percentage of T gamma cells and T cell was significant in the patients with primary breast cancer prior to radical mastectomy.