Desmoplastic melanoma (DM) is a rare variant of melanoma. Most frequently, it seems as clinically ambiguous and histologically characterized by a poorly demarcated neoplasm composed of a proliferation of spindle melanocytes dispersed in a prominent collagenous stroma. It often represents a diagnostic challenge, delaying its detection. We analyzed the expression profile of 29 (28 “pure” and 1 “combined”) DM. These data were compared with a series of 62 primary vertical growth phase nondesmoplastic melanomas (NDMs) using a set of proteins including melanocytic markers (S-100 protein and melan-A) and epithelial–mesenchymal transition (EMT)–related proteins (E-cadherin, N-cadherin, SPARC, WT1, and PKCα). The S-100 protein confirmed the melanocytic origin of the DM (positive in 96%). The significant positive expression of N-cadherin, SPARC, and WT1 in DM (61%, 82%, and 71%) compared with NDM (28%, 43%, and 47%; P < 0.05) and a lower expression of E-cadherin in DM (14%) compared with NDM (61%) support specific adhesive and migratory properties of DM tumor cells. The study was carried out with tissue microarrays that partly limited the study of the tumor sections. This study demonstrates, for the first time, a prominent expression of epithelial–mesenchymal transition–related proteins in DMs and tries to be one more step in refining its knowledge and leading to a better understanding of its biological and clinical behaviors.
*Department of Pathology, 12 de Octubre University Hospital, Complutense University, Madrid, Spain;
†Department of Dermatology, Fundación Jiménez Díaz, Autonoma University, Madrid, Spain;
‡Dermatopathologie Bodensee, Friedrichshafen, Germany;
§Department of Dermatology, 12 de Octubre University Hospital, Complutense University, Madrid, Spain; and
¶Environmental and Cancer Epidemiology Unit, National Center for Epidemiology (CIBERESP), Carlos III Institute of Health, Madrid, Spain.
Reprints: Maria Concepción Garrido, MD, PhD, Dpto. de Anatomía Patológica, Hospital Universitario12 de Octubre, Avda de Córdoba s/n, Madrid 28041, Spain (e-mail: firstname.lastname@example.org).
Supported by grants from the Ministerio de Sanidad y Consumo Fondo de Inversiones Sanitarias (FIS PI 080405) and the Fundacion Mutua Madrileña (FMM 2008-106).
The authors declare no conflicts of interest.