Results: A consistent finding in skin samples containing BCC was the absence of CD34 in the following extravascular structures: neoplastic cells, epidermis and its derivatives (except for the cells of the isthmic part of the outer hair follicle sheath), fibroblast-like cells of BCC tumor stroma, as well as in the papillary dermis in the tumor region. The gene discussed is CD34; the disease is skin basal cell carcinoma.