The sebaceous epithelioma is a rare variety of skin tumor, the histogenesis of which
is not clearly elucidated. Their clinical character, localization and age incidence are very
similar to basal cell epithelioma, but they have small number of mature sebaceous cells
as tumor element, The main pathologic finding is proliferation of basaloid germinative
cells of the sebaceous glands.
We experienced a case of a recurrent sebaceous epithelioma of the right parotid area
in a 37-year-old woman. She had her tumor removed at the same site one year
previously. The clinical impression was neoplasm of salivary glands.
The tumor was located just beneath the focally ulcerated skin, and was partly
encapsulated and lobulated and measured 4×2.5×2.5cm. Cut surface was homogeneously
yellowish white, showing lobule formation by fibrous septa of varying thickness. Areas
of hemorrhage and cystic change were seen.
Microscopically there were poorly defined masses of cells of basaloid shape. There
were many cystic spaces, containing amorphous hyaline-like material. This material
appeared foamy and in glaces vacuolated. The tumor masses consisted of two cell types,
one was similar to that seen in the basal cell epithelioma and the other was sebaceous
in nature. Germinative cells were predominant throughout and invaded the fibrous septa.
Mild inflammatory infiltrates were present in areas. The overlying epidermis was
relatively well maintained except for focal ulceration.
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