The immunobiology of basal cell carcinoma: an in situ monoclonal antibody study.

A semi-quantitative, immunoperoxidase monoclonal antibody technique was used to study the mononuclear cells surrounding 32 basal cell carcinoma specimens from 30 patients. Tumours were analysed in subgroups based on recurrence, size and ulceration. T cell counts were high (greater than 3 out of 4) for all groups while T helper/inducer and T suppressor/cytotoxic cell counts were equal (approx. 2). Macrophage counts were low for all groups, about I X 2, while B cell and Ia positive cell counts were high (greater than 3). T/B cell and T helper/suppressor cell ratios approached one for the tumours as a whole as well as the sub-groups. The relative importance and contribution of cell mediated vs. humoral immunity in keeping basal cell carcinomas in check is discussed.