Cutaneous ciliated cyst of the right lower leg.

A 23-year-old Japanese woman with a cutaneous ciliated cyst on her right lower leg is reported. A subcutaneous cyst, measuring 2.5 cm in diameter with papillary projections into the lumen, was lined with ciliated cuboidal to columnar epithelia with partial stratification, histologically. These lining cells did not produce mucin. Immunohistochemically, the ciliated lining cells of the cyst were diffusely positive to epithelial membrane antigen and cytokeratin. In addition, positive immunoreaction with anti-desmin monoclonal antibody was observed in the body of the cilia. Less than 10% of the epithelial cells revealed positive immunoreaction to S-100 protein and estrogen receptor.