Anti-tumor immunity in breast cancer evaluated by a computerized tube leukocyte adherence inhibition (LAI) assay.

Seventy-four women admitted for breast biopsy were monitored before surgery for anti-tumor cell-mediated immunity using a computerized tube leukocyte adherence inhibition (LAI) assay. Spent medium from breast, lung and colon adenocarcinoma cell lines was used as the source of organ-specific neoantigens for standardization of the assay. Peripheral blood leukocytes from 25/40 (62.5%) patients diagnosed after surgery as breast cancer responded to spent medium with a positive non-adherence index (NAI). A positive NAI was inversely related to tumor mass because only 7/18 (38.8%) of those with Stage III or IV had a positive NAI; while 18/22 (81.8%) of those with Stage I or II were positive. Cross-reactive antigenicity was not observed when spent medium from breast cancer was incubated with leukocytes from patients with several other solid tumors nor when leukocytes from breast cancer patients were incubated with spent medium from lung or colon carcinoma cell lines. The antigenic material in the spent medium appears to be an organ-specific neoantigen because only 1/34 patients with benign breast disease had a positive NAI and all normal healthy control individuals were negative. The results of this study show that spent medium of a breast carcinoma cell line is more reliable than crude cancer extracts for use in LAI to detect specific anti-tumor cellular immune responses. The improved method presented in this report can be a useful tool in the early diagnosis of breast cancer and for monitoring of patients with this disease.