Malignant form of hidroacanthoma simplex: A case report

Figure 1 Clinical image and dermoscopic examination of the tumour. A: Clinical picture; B and C: Dermoscopic images of the lesion. (B) ×50, (C) ×50.

Figure 2 Histopathological and immunohistochemical analysis. A-C: Haematoxylin and eosin staining of resected specimen (A) ×40, (B) ×200, (C) ×400. A: Blunted epithelial feet (white arrow); B: Neoplastic cells were less stained than the surrounding epithelium (black arrow); C: Dyskeratotic cells (white circle) and mitotic figures (black arrows); D: Immunohistochemical staining showed positivity for CK5/6 (×40); E: EMA (×40); F: CEA was only expressed in ductal structures ×200.