Unspecific cellular immunity before therapy in patients with squamous cell carcinoma of head and neck

Abstract

An introduction to the role of lymphocytes in immunological reactions is given. Two fundamental categories of immunological response are described which are mediated by two distinct subpopulations of lymphocytes: B-lymphocytes are responsible for humoral immune reactions and T-lymphocytes are involved in cell-mediated immunity. Information is given on the role of the immune system in generation of anti-tumour activities and of mechanisms leading to an acceleration of tumour growth. Several pathways of cytotoxic and blocking reactions against target cells are mentioned. Furthermore, methods are described for monitoring the non-specific immune reactivity of the host. These nonspecific cellular immune responses in 30 patients with squamous cell carcinoma of the head and neck were compared with those in 30 healthy controls. Assays were performed in vitro to evaluate the blastogenic response of lymphocytes to the mitogens PHA (phytohaemagglutinin) and PWM (pokeweed mitogen) and to quantify T-rosetteforming lymphocytes in the peripheral blood. The in vivo assays used were the delayed cutaneous hypersensitivity reaction to the primary stimulus of DNCB (dinitro-chloro-benzene) and the recall reaction to PPD (purified protein derivate). The carcinoma patients demonstrated significant impairment of lymphocyte blastogenesis reactions to PHA but not to PWM. The percentage and absolute counts of T-rosettes was significantly reduced in cancer patients compared with normal controls. Skin test reactivity to de-novo sensitation with DNCB was significantly abnormal in patients with head and neck cancer. However, delayed type hypersensitivity evaluated with PPD (recall antigen) was not significantly reduced. After subdividing the cancer patients according to their clinical stage of disease and subsequent analysis, they showed no correlation between clinical stage and immune reactivity. These data indicate that PHA induced lymphocyte blastogenesis, enumeration of T-rosette levels and evaluation of delayed hypersensitivity reaction to DNCB are potentially useful for the study of squamous cell carcinoma of head and neck to monitor effects of tumour treatment and perhaps to evaluate a correlation between immunocompetence and prognosis.