Immunosuppression caused by head and neck surgery

The immunomodulating effect of primary surgical intervention was investigat ed in 33 patients with squamous cell carcinomas of the oral cavity, pharynx and larynx. An operation time longer than 7 h was significantly associated with a decrease in lymphocytes, CD4(+) T-lymphocytes and CD8(+) T-lymphocy tes. The CD4/CD8-ratio as a marker for the dawn-regulation of the cellular immune response was slightly decreased but was still in the normal range. C D4-lymphocyte counts increased 7 days after operation while CD8 lymphocytes were found elevated 4 weeks after sugery. The in vitro stimulation of the lymphocytes was impaired for 1 to 4 weeks. Interleukins, interferon-gamma a nd tumor necrosis factor did not show any changes after surgery. Decreases of lymphocytes, especially CD4(+) and CD8(+) lymphocytes, were significantl y associated with the time of operation and the volume of blood loss. Exten sive trauma, age, different kinds of anesthesia and intensive care interven tions were not associated with specific immunomodulating effects, although these factors might be responsible for suppressing cytokine responses.