Bowen Disease With Sebaceous Differentiation: A Case Report and Immunohistochemical Analysis of Adipophilin and Cytokeratin 1.

Bowen disease with sebaceous differentiation has been rarely documented to date. Here, we present a case of Bowen disease with sebaceous differentiation. A 67-year-old man presented with a 6.0 × 3.5 cm erythematous plaque adjacent to a 7.0 × 3.0 cm erythematous plaque on his left abdomen. Dermoscopy revealed yellow structureless areas and dotted vessels on a pink homogenous background in addition to surface scales. Histopathological examination of the upper erythematous plaque showed parakeratosis and acanthosis with proliferation of atypical keratinocytes in the epidermis. Some of the atypical cells had large and hyperchromatic nuclei. Histopathological examination of the lower erythematous plaque showed tumor nests extending from the epidermis. Tumor nests with hyperchromatic and atypical cells had vacuolated cells. The diagnosis of Bowen disease with sebaceous differentiation was made. Immunohistochemistry revealed a positive reaction for cytokeratin 1 (CK1) in tumor cells of Bowen disease and a negative reaction for CK1 in tumor cells with the sebaceous differentiation, whereas immunohistochemistry revealed no apparent adipophilin-positive granules in tumor nests of Bowen disease compared with the prominent staining of adipophilin in tumor nests with sebaceous differentiation. We show Bowen disease with sebaceous differentiation taking advantage of immunohistochemistry of adipophilin and CK1. Those findings of Bowen disease with sebaceous differentiation may deepen our understandings and insights into the pathogenesis of sebaceous carcinoma and Bowen disease.