Basal cell carcinoma in association with multiple trichoepitheliomas.

We report the case of a basal cell carcinoma (BCC) associated with multiple trichoepitheliomas (TEs) and include the results of histopathological and immunohistochemical studies. The patient had a large, pigmented nodule associated with 4 flesh-colored papules in the central facial area. Two of the 4 flesh-colored papules and the large pigmented nodule were excised. Histopathologically, the pigmented nodule was diagnosed as BCC and 2 of the papular lesions were diagnosed as TEs. In both the BCC and TEs, almost all of the basaloid aggregations were diffusely positive for cytokeratin (CK) 19, CK8 and CK8/18. Based on these clinicopathological observations and reports in the recent literature, these two neoplasms are considered to be highly related. BCC appears to differentiate toward follicular germinative cells, and TE is its benign counterpart.