Syringocystadenoma papilliferum and trichoblastoma arising in the nevus sebaceous.

Nevus sebaceous (NS) is a clinically common benign tumor and has a high potential to develop into a great diversity of neoplasms of epidermal and adnexal origins. However, it is a rare phenomenon of the coexistence in a single NS with two or more skin tumors. We report a case of a 58-year-old woman with two kinds of neoplastic proliferation including syringocystadenoma papilliferum and trichoblastoma arising in NS on the scalp.