Histopathology. a: Overview image: Epidermis, followed by dermis with hair follicles and sebaceous glands. Tumour with unclear borders in the depth (H&E, 16×). b: In detail: Atypic, swollen endothelial cells with anastomosing, pseudopapillar patterns and lymphocytic inflammation (H&E, 200×). c: Immunohistochemistry with proliferation marker MIB-1 indicating proliferation in about 5%–10% of the cells (MIB-1, 200×). d: Positive immunohistochemical reaction to the endothelial marker CD 31 (CD 31, 200×).