| Abstract: | Two cases of irritated seborrheic keratosis ofthe eyelid were studied clinicopathologically. One
unusually large tumor was confirmed benign electron
microscopically. Under light microscope, irritated
seborrheic keratosis was diagnosed by the presence of
its "stuck on" configuration, numerous horn cysts,
and squamous eddies among the proliferated basaloid
and squamoid cells. Ultrastructurally, both the
basaloid cell and squamoid cell showed high
differentiation and well-formed organelles in the
cytoplasm. The nuclear chromatin was even and
fine, and the nuclear membrane smooth and regular.
Tonofilaments and desmosomes could be found.
These ultrastructural findings were consistent with
the concept that seborrheic keratosis develops on the
basis of local arrest of keratocyte maturation. |
