Original StudySquared-Off Nuclei and “Appliqué” Pattern as a Histopathological Clue to Periocular Sebaceous Carcinoma: A Clinicopathological Study of 50 Neoplasms From 46 PatientsBroekaert, Sigrid M. C. MD*; Flux, Katharina MD†; Kyrpychova, Liubov MD‡; Kacerovska, Denisa MD, PhD‡,§; Ivan, Doina MD¶; Schön, Michael P. MD*; Ströbel, Philipp MD‖; Michal, Michal MD‡; Denisjuk, Natalja MD**; Kerl, Katrin MD††; Kazakov, Dmitry V. MD, PhD‡,†† Author Information *Department of Dermatology, Venereology and Allergology, University Medical Center Göttingen, Göttingen, Germany; †Dermatohistology and Oral Pathology Laboratory, Munich, Germany; ‡Department of Pathology, Faculty of Medicine in Pilsen, Charles University in Prague, Pilsen, Czech Republic; §Bioptical Laboratory, Pilsen, Czech Republic; ¶Department of Pathology, University of Texas-MD Anderson Cancer Center, Houston, TX; ‖Department of Pathology, University Medical Center Göttingen, Göttingen, Germany; **Dermatopathology Laboratory, Zurich, Switzerland; and ††Department of Dermatology, University Hospital, Zurich, Switzerland. Reprints: Dmitry V. Kazakov, MD, PhD, Sikl's Department of Pathology, Charles University Medical Faculty Hospital, Alej Svobody 80, Pilsen 304 60, Czech Republic (e-mail: [email protected]). Supported in part by the Charles University Research Fund (project number SVV-2016-260 282). The authors declare no conflicts of interest. The American Journal of Dermatopathology 39(4):p 275-278, April 2017. | DOI: 10.1097/DAD.0000000000000651 Buy Metrics Abstract The histopathological diagnosis of periocular sebaceous carcinoma can be difficult in poorly differentiated cases showing few mature sebocytes. The authors examined 50 periocular sebaceous carcinomas from 46 patients to determine the frequency of 2 features seen in this neoplasm, namely cells with squared-off nuclei and so-called “appliqué” pattern (peritumoral subnecrosis of peripherally located neoplastic cells). Neoplastic cells with squared-off nuclei were found in varying numbers in both the intraepithelial and dermal (invasive) components in all neoplasms, whereas the appliqué pattern was observed in a third of the cases. It is concluded that these features, taken together, may serve as a clue for the diagnosis of periocular sebaceous carcinoma. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.