| Abstract: | A large intradermal tumor, 5times4 cm in size, developed on the back of 67-year-old Japanese woman. Histological examination revealed a large cyst next to a mass of irregular proliferation of the cystic wall, most of which showed typical trichilemmal keratinization. The accompanying partial calcification of the homogeneous cystic content allowed the diagnosis of proliferating trichilemmal cyst. Since this tumor is quite rare among the Japanese, the 15 cases so far reported in the Japanese literature are reviewed and summerized. |
