Immune restoration with interleukin-2 in patients with squamous cell carcinoma of the head and neck.

Patients with head and neck squamous cell carcinoma commonly have depressed cell-mediated immunity which is known to correlate with ultimate prognosis. Selective immune studies were conducted in 27 head and neck cancer patients to determine the potential of interleukin-2 as an immune restorative agent. Patients showed the expected depression of lymphocyte proliferation to phytohemagglutinin and had borderline depressed natural killer cell activity and relatively normal interleukin-2 production. Addition of interleukin-2 at 100 units/ml markedly enhanced natural killer cell activity to normal levels. Serum from head and neck patients was also immune-suppressive. Heat-inactivated serum depressed lymphocyte proliferation and natural killer cell activity of control leukocytes. Lymphocyte incubation with interleukin-2 significantly counteracted immune suppressive serum effects and restored depressed lymphocyte function to normal levels. The effective in vitro interleukin-2 dose is potentially achievable by infusion at approximate doses of 3 X 10(6) units/M2.