Tumoral infiltrate after local treatment with interferon in squamous cell carcinoma.

Using monoclonal antibodies UCHL-1 (T lymphocytes), MT-1 (pan T) and L-26 (B lymphocytes) in the study of the tumoral infiltrate after local treatment with alpha interferon (Roferon) in patients with squamous cell carcinoma of the lower lip, it was observed that: the proportion of UCHL-1 positive cells was between 30% and 80%, the proportion of MT-1 positive cells was of 85% and that of the L-26 positive cells was of 30% of all the cells in the infiltrate. In the area in which after treatment with interferon the tumoral structures had disappeared, the proportion of T lymphocytes was smaller than in the areas in which the tumoral structures were still present. The therapeutic effect of interferon is due both to the direct effects on the tumoral cell and also to the indirect effects, namely the activation of the cytotoxic T lymphocytes and of other cells in the tumoral infiltrate.