Immune reactivity in bronchogenic carcinoma and its relation to 5-year survival rate

Immune cell infiltrates and prognosis in primary carcinoma of the lung

The prognostic significance of immune cell infiltrates in surgically resected human lung cancer was investigated in 710 patients. Lymphoid infiltrates were quantified on both standard H&E stained sections and, in a subset of 95 cases, using immunohistochemistry and antibodies to CD3, CD8, CD57, CD68, CD79a and S100 to identify various immune cell types. Subjective grading (low, moderate, high) of lymphoid cell infiltrates on H&E sections of tumour and measurement, using image analysis, of overall level of tumour infiltration by any of the immunohistochemically labelled specific immune cell types of the stained sections showed no prognostic significance. However, when a distinction between peritumoural and intratumoural infiltration by particular cell types was made, intratumoural infiltration by high levels of CD3+ and S100+ cells was associated with longer post-operative survival (P = 0.02 and P = 0.045, respectively). In lung cancer, subjective assessment of tumour lymphoid infiltration and overall levels of infiltration by particular immune cell types carries no prognostic significance. Intratumoural infiltration by relatively high numbers of CD3+ T-lymphocytes and Langerhans cells (S100+) is associated with a better patient outcome.

Bronchogenic carcinoma: immunologic aspects

Evidence that host immunologic function may influence the behavior of lung cancer is accumulating. Non-small-cell lung cancers are heavily infiltrated by host lymphocytes. The fact that monoclonal antibodies have been developed against lung cancer cells implies that such cells express surface antigens and are therefore vulnerable to immune recognition. Failure of the host defense mechanism to control tumor growth may involve (1) reduced natural killer cell activity, (2) inadequate lymphokine-activated killer cell function, or (3) tumor secretion of immunomodulating factors. Basic immunologic research studies of lung cancer are increasing the potential for clinical applications. New monoclonal antibodies have improved both the sensitivity and the specificity of immunohistopathologic analyses of pulmonary specimens. Links between immune function and prognosis in patients with lung cancer have been established. Finally, initial results from protocols that have used tumor-infiltrating lymphocytes, interleukin 2, and tumor vaccines suggest that immunobiologic treatment modalities may be increasingly applicable in patients with lung cancer.