Effects of operation on immune response in cancer patients: sequential evaluation of in vitro lymphocyte function.

The effect of operation on in vitro lymphocyte function in 35 cancer patients was studied. Lymphocyte proliferative responses to phytohemagglutinin (PHA), poke-weed mitogen (PWM), and concanavalin A (Con A) were measured by 3H-thymidine incorporation. Sheep red blood cell (SRBC) rosette formation also was quantitated. These tests were performed preoperatively and at 24 hours, one week, and 4 weeks postoperatively. Intra-abdominal and intrathoracic procedures, transfusions, and longer operating times depressed the lymphocyte proliferative response. However, an increased lymphocyte proliferative response was noted in sarcoma patients 24 hours postoperatively, possibly as a result of lowered tumor burden. Several of these changes still were evident 4 weeks after operation. Rosette formation also decreased significantly 24 hours postoperatively in patients who had intrathoracic or intra-abdominal procedures, but returned to preoperative levels after one week. In general, operation appears to cause transient depression of lymphocyte function in some cancer patients. However, lymphocyte function returns to normal by the fourth postoperative week in most patients.