Immunologic study of carcinoma of the digestive tract. Effects of the tumor stage. I. Cellular immunity in the preoperative period.

We studied the behavior of the cellular immune system in two types of carcinoma of frequent clinical occurrence: large bowel and gastric cancers. We contrasted both types of neoplasia with respect to the behavior of cellular immunity in the preoperative period, according to the evolutive stage of the tumor. Two hundred and nine subjects were studied: 86 with gastric adenocarcinoma, 63 with adenocarcinoma of colon-rectum and 60 healthy controls. Total lymphocytes were quantitated, as were B and T cell subpopulations, and T cell function by measuring the response to PHA. Summarizing the results, a clear depression in cellular immunity was observed in stage III of gastric cancer. In large bowel cancer the repression of cellular immunity is of lesser magnitude than in gastric cancer.