Trichoblastoma with rippled-pattern.

The following is a case study of a 36-year-old Japanese man with a trichoblastoma which exhibited a rippled-pattern on the left temporal region of the scalp. The histological findings of the tumor revealed lobular aggregations composed of immature follicular basaloid cells, lobules of squamous eddy-like foci of incomplete keratinization or small keratinous cysts, and multiple papillary mesenchymal bodies similar to hair germ. Interestingly, a rippled-pattern of basaloid cells and hyalinized matrixes resembling the Verocay bodies of neurilemmoma was also observed. We propose that the rippled-pattern of the basaloid cells and hyalinized matrices is caused by the characteristic stromal induction of trichoblastoma.