Hyaline cells in a benign chondroid syringoma. Report of a case and findings by conventional and electron microscopy

This report describes the features of a benign chondroid syringoma removed from a foot of a 34-year-old woman. Histologic examination showed that an acidophilic hyaline cell was the predominant cell type; keratinocytes and cells with clear to foamy cytoplasms were less abundant. The hyaline cells and keratinocytes were within a chondroid and myxoid stroma. Ultrastructural study revealed large numbers of pale epithelial cells whose cytoplasms were loaded with intermediate filaments and dark cells with many tonofilaments. Intermediate transition forms between the pale and dark cells were also identified, as were myoepithelial cells with intermediate filaments, and secretory cells. These cells were also lodged in a chondroid and myxoid matrix. This study showed that acidophilic hyaline cells are of both epithelial and myoepithelial origin and that both may be responsible for laying down the matrix.