The clear-cell variant of uterine epithelioid leiomyoma. An immunohistologic and ultrastructural study.

A case of a rare uterine clear-cell epithelioid leiomyoma is presented, emphasizing immunohistologic and ultrastructural findings. The presence of actin, vimentin, desmin, muscle-specific antigen, and smooth-muscle-specific actin in tumor cells indicates a smooth-muscle origin, confirmed by electron microscopy. Numerous vacuolated mitochondria produced the cytoplasmic "clearing" on light microscopy.