HISTAMINE IN HUMAN BREAST-CANCER

Background Histamine inhibits lymphocyte function in vitro at concentr ations of greater than 10(-6) mol/l. The aim of this' study was to det ermine whether histamine concentrations in breast cancers were suffici ent to produce an immunological effect. Methods Tumour and adjacent no rmal breast content of histamine was measured using a radioenzymatic a ssay in 29 patients having surgery for breast cancer. Results The medi an content of histamine in breast cancer tissue was 5.4 (range 0.9-27. 3) mu g/g (median concentration 4 5 x 10(-5) mol/l), and was significa ntly greater than that in adjacent breast tissue (P = 0.007). Conclusi on The concentration of histamine in breast cancer was sufficient to i nhibit lymphocyte function and could be locally immunosuppressive.