Exposure of cryptantigens on erythrocytes in patients with breast cancer.

One hundred thirty-two patients with breast cancer were examined for exposure of cryptantigens on their erythrocytes (RBC) using a lectin panel consisting of Arachis hypogaea and Glycine soja. Eight had exposed cryptantigens; of the eight, five were classified with additional lectins as T-polyagglutination type and three as Th-polyagglutination. A control group of 300 healthy blood donors had no exposed cryptantigens on their RBC. These findings could not be correlated with the staging of the tumor, extension of metastases, or positive estrogen or progesterone receptors of malignant tumor cells. Only one study has been found that describes the incidence of agglutination of erythrocytes from cancer patients using a monoclonal antibody, which detected an epitope on the RBC from cancer patients and was considered to be distinct from the antigen bound by naturally occurring anti-T. Studies have been made describing polyagglutinable sites on breast cancer tumor cells, where there was a much higher incidence. This discrepancy can be explained either by a difference in the methods used to search for cryptantigen exposure on the various types of cells, or by the existence of a different mechanism, which causes the exposure of cryptantigens on RBC as opposed to malignant breast tumor cells.