Immunocompetence and its modification after BCG immunotherapy in patients with colon carcinoma.

The ability to develop cutaneous response to Mantoux, phytohemagglutinin (PHA) and dinitrochlorobenzene (DNCB) was studied in patients with carcinomas in the digestive tract, with particular emphasis on cancer of the colon, in patients with benign pathology and in a control group. The patients with a malignant disease in the digestive tract, considered as a group, showed a remarkable decrease of responses to Mantoux (31%), to PHA (21%) and to DNCB (58%) compared to the control group where incidence amounted to 61%, 73% and 100% respectively. The depression in the immune cellular response is more remarkable yet in colon carcinoma (Mantoux 11%, PHA 0%, DNCB 11%) all of which suggest that the impairment of the immune response depends on the tumor localization.