Cutaneous lymphadenoma. A basal cell carcinoma with unusual inflammatory reaction pattern?

Two additional cases of cutaneous lymphadenoma (CL) are reported. The lesions presented as single nodules of many years' duration on the face. Histologically, the neoplasms consisted of irregularly shaped lobules immersed in a dense fibroblastic stroma involving the whole dermis and extending into the subcutaneous fat. Duct-like structures suggesting an eccrine differentiation were recognized. The lobules were composed of a rim of basaloid cells surrounding large epithelioid cells and lymphocytes. In some areas the basaloid lobules were only partly replaced by the inflammatory cells. Immunohistochemically, the intralobular inflammatory component was composed of a mixed B- and T-cell population and S-100-positive dendritic cells. The observation of these cases suggests that CL is not a distinct entity but may represent a basal cell carcinoma, possibly with pilar or eccrine differentiation, in which an immune host reaction pattern is exceedingly unusual.