Lymphocyte reactivity in patients with cancer of the oral cavity measured by sister chromatid differential staining.

Lymphocyte reactivity in phytohemagglutinin-stimulated peripheral lymphocyte cultures from 22 patients with squamous cell carcinoma of the oral cavity and 29 age- and sex-matched controls was measured by the bromodeoxyuridine-Giemsa method for demonstrating sister chromatid differential staining. One hundred metaphases from each donor were counted, and the proportions of cells in the first, second, and third cycles were scored to estimate the in vitro mitogen responsiveness and cell division rates of the lymphocytes. The in vitro reactivity of peripheral lymphocytes of cancer patients was impaired in comparison with that of the controls, and the degree of reactivity of lymphocytes in cancer patients was not related to the size (greatest diameter) of the primary tumor. Results are discussed in relation to previously existing data.