title: Plasma blood group changes in gastrointestinal tract carcinoma.
abstract: The levels of A, H, I, and i plasma antigens and of anti-B, anti-I, and anti-T antibodies were measured in 70 subjects with colonic or gastric carcinoma. These studies showed a significant increase in A plasma activity of the A subjects, and in H plasma activity of the O subjects, while 25% of the tested subjects showed increased I plasma activity. There was no difference in i plasma activity between cancer patients and healthy subjects. These results take into account the marked polymorphism acquired by neoplastic tissue, which is capable also of producing a greater quantity of antigens than that of healthy subjects. Nevertheless this heterogeneity forms a barrier to the clinical measurement of these plasma antigens for screening neoplasms. The significant fall in the amount of anti-T antibodies seemed to be secondary to the absorption of these antibodies on the surface of the tumour cells.
mesh_terms: D000017:ABO Blood-Group System / Q000276:immunology; D000328:Adult; D000368:Aged; D001789:Blood Group Antigens / Q000276:immunology; D003110:Colonic Neoplasms / Q000097:blood* / Q000276:immunology; D005260:Female; D006801:Humans; D007048:I Blood-Group System / Q000276:immunology; D007518:Isoantibodies / Q000032:analysis; D008297:Male; D008875:Middle Aged; D013274:Stomach Neoplasms / Q000097:blood* / Q000276:immunology
chemical_list: D000017:ABO Blood-Group System; D001789:Blood Group Antigens; D007048:I Blood-Group System; D007518:Isoantibodies