Immunomodulating effects of surgical intervention in tumors of the head and neck

The immunomodulating effect of primary surgical intervention in 33 patients with squamous cell carcinoma of the oral cavity, pharynx, and larynx was a nalyzed prospectively. An operation time of longer than 7 hours was signifi cantly associated with a decrease of total lymphocyte counts, CD4(+) T lymp hocytes, and CD8(+) T lymphocytes. The CD4/CD8 ratio as a marker for the do wnregulation of the cellular immune response was slightly decreased but sti ll in the normal range. CD4(+) lymphocyte counts increased within 7 days, a nd CD8+ lymphocytes increased 4 weeks after the operation. The in vitro sti mulation of the lymphocytes was impaired for 1 to 4 weeks. Release of inter leukins, interferon-gamma, and tumor necrosis factor-alpha remained low des pite the surgical trauma. The decreased lymphocyte counts, especially CD4() and CD8(+) lymphocytes, were significantly associated with duration of op eration and volume of blood loss. Extension of trauma, age, type of anesthe sia, and type of intensive care intervention were not associated with speci fic immunomodulating effects. However, these factors might be responsible f or suppression of the immune system, which is expressed by lymphocyte deple tion, lymphocyte dysfunction, and impaired upregulation of cytokine secreti on.