Antibody-producing Capacity in Human Cancer*

The antibody response to primary immunization with monomeric flagellin from Salmonella adelaide was studied in 61 patients with cancer and antibody-producing capacity was correlated with survival. In 27 patients suffering from “active” cancer, antibody-producing capacity was significantly depressed (P<0.05) as compared with sick but not cancerous controls; in 13 such patients who survived more than 6 months after immunization, antibody-producing capacity was moderately depressed, whereas in 14 who survived less than 6 months, the capacity was markedly depressed. In 34 patients with “cured” cancer, by surgery and/or radiotherapy, antibody-producing capacity was significantly greater than that of the “hospital” controls and patients with “active” cancer, but yet was significantly less than that of healthy subjects. Three explanations for the findings were considered: an immunodepressive effect of general debility, an immunodepressive effect specific to cancer and, on the other hand, the occurrence of cancer preferentially in individuals with an impaired capacity for antibody production. The present findings gained added relevance from recent evidence that a specific humoral immune response is evoked by antigens of certain types at least of human cancer.