O ~I defcitse against cancer probably ex-H ists to a significant degree. T h e development of clinical cancer may indicate an impaired resistance, one manifestation of which could be an altered antibody response to standard antigens.
T h e ability of patients with chronic leukemia to form antibodies to typhoid vaccine has been shown to be somewhat depre~sed.~, 8 T h e subject of heterophile antibody titers was recently reviewed by Southam et aL8 who concluded that these are not elevated in the leukemias. A decline in incidence of proteus agglutinins was found in patients with active cancer.7 O n the other hand n o difference was found in mumps-virus antihemagglutinin titers between patients with cancer and those without.5 Larson and Tomlinson4 applied the quantitative precipitin technique of Heidelberger and associates2 to the study of leukemia, 1 ymphow-coma, and Hodgkin's disease and found an unusually large antibody response among those with acute leukemia and an impaired response among those with chronic leukemia. In the present study the antibody response of cancer patients and of noncancer patients to pneumococcal polysaccharides, diphtheria toxoid, and tetanus toxoid is compared.