[Basal cell carcinoma with matrical differentiation].

Basal cell carcinoma with matrical differentiation is a very rare variant of basal cell carcinoma. To our knowledge, less than 30 cases have been reported. This tumor is composed of basaloid lobules showing a differentiation toward the pilar matrix cells. Recently, it has been demonstrated that beta-catenin would interfer with physiopathogenesis of matrical tumors, in particular pilomatricomas, but also basal cell carcinomas with matrical differentiation. This is a new case, with immunohistochemical and molecular analysis of beta-catenin, in order to explain its histogenesis.