Gastric Carcinoma With Sebaceous Differentiation and SALL4 Expression

A sebaceous carcinoma is rarely seen in extracutaneous sites. We present a 75-year-old man who was admitted with epigastralgia and melena. Endoscopic examination revealed an ulcer on the posterior wall of the gastric antrum, and distal gastrectomy was performed. Histopathological examination revealed thin to thick trabeculae of polygonal cells with scattered foci of foamy cells, whereas Sudan 3 staining showed lipid vacuoles. Immunohistochemistry was positive for both p40 and SALL4. After considering these findings, we suggest sebaceous differentiation as the diagnosis. To the best of our knowledge, this is the first case of gastric carcinoma with sebaceous differentiation.