RESUMO
BACKGROUND: The cytotoxic activity and count of natural killer (NK) cells appear to be reduced after surgery; however, it is unknown whether the magnitude of this immune suppression is similar among different types of oncological surgery. In this study, we compared the innate immune function of patients undergoing three different oncological surgeries. METHODS: We compared the number and function of NK cells obtained from patients who had undergone mastectomies (n = 17), thoracotomies (n = 21), or liver resections for cancer (n = 22). Cytotoxicity assays were performed to measure the function of NK cells. We also determined the plasma concentrations of interleukins (IL) 2 and 4, interferon-γ, granzyme B, perforin, soluble major histocompatibility complex class I-related chain A, and epinephrine, both before and 24 h after surgery. Differences in immunologic parameters were compared preoperatively and postoperatively and by type of surgery. P values <0.05 were considered statistically significant. RESULTS: The preoperative NK cell count differed statistically (P < 0.006) among all three types of surgeries; however, within surgery postoperative counts and changes compared with baseline did not. The postoperative function of NK cells was similar among types of surgeries, but was significantly reduced compared with preoperative levels (mastectomy P < 0.0001, thoracotomy P = 0.001, and liver resections P = 0.002). We observed a significant increase in the postoperative plasma concentrations of epinephrine, whereas the concentrations of major histocompatibility class I polypeptide-related sequence A and the IL-2 and/or IL-4 ratio remained unchanged before and after surgery. CONCLUSIONS: The magnitude of innate immune suppression is similar among different oncological procedures. More studies are needed to better understand this complex phenomenon.