Multiple Linear Eccrine Spiradenoma Associated with Multiple Trichoepithelioma

A 37‐year‐old woman had multiple trichoepithelioma of the face which showed typical clinical and histological features, together with multiple papular lesions of 30 years' duration. The lesions were arranged in a linear fashion on her right breast and right upper arm. Microscopic examination of a biopsy specimen revealed typical eccrine spiradenomas. An ultrastructural study of the tumor on the breast revealed that it was composed of two main types of cells: one was a clear cell with low‐density cytoplasm and the other was a dark cell with high‐density cytoplasm. Some of the clear cells had secretory granule‐like structures and/or tono‐fibrils, while others had intracytoplasmic cavitations. Neither myoepithelial cells nor Langerhans cells were observed.