Immunologic study of carcinoma of the digestive tract. Influence of tumor staging. II. Humoral immunity in the preoperative period.

The studies of levels of circulating immunoglobulins in cases of solid neoplasia in man have yielded discordant results, especially in cases of colon and rectal cancer. The possible prognostic value of the quantitation of these parameters has been discussed, and some have even suggested that certain fluctuations in immunoglobulin levels may indicate the development of metastases. We studied the behavior of humoral immunity in 88 patients with gastric adenocarcinoma, 63 patients with cancer of the colon and 60 healthy controls. The cancer patients were grouped according to tumor stage. Serum levels of IgG, IgA and IgM were determined in the preoperative period. The results show a significant decrease in IgG titers in all stages of gastric cancer but more so in the initial stages of development. In the cases of cancer of the colon, the IgG reduction was most evident in the advanced stages of disease. IgA levels were significantly elevated in stage III of gastric cancer and all stages of cancer of the large intestine. IgM levels in gastric cancer behave in a similar manner as IgA, and is elevated in the final stages of cancer of the colon.