Preservation of in vitro biological functions in regional lymph node lymphocytes in squamous head and neck cancer

Regional lymph node lymphocytes from patients with squamous cancer of the head and neck were tested in vitro for their ability to proliferate in response to phytohemagglutinin, concanavalin A, and allogeneic stimuli in one-way mixed lymphocyte culture. Their ability to act as cytotoxic effectors in phytohemagglutinin-dependent cellular cytotoxicity was also evaluated, and all results were compared to normal lymph node or blood lymphocytes. The regional lymph node lymphocytes retained proliferative capabilities equal to those in control lymph nodes or blood, whereas they were unable to mediate phytohemagglutinin-dependent cellular cytotoxicity. However, this was not a tumor-related effect because normal lymph node lymphocytes were also ineffective in this assay. The failure of the regional immune response to control early tumor growth could not be accounted for by generalized nonspecific immunosuppression in regional lymph node lymphocytes, inasmuch as these cells demonstrated normal in vitro activity.