Stanoszek, Lauren M; Chan, May P; Palanisamy, Nallasivam; Carskadon, Shannon; Siddiqui, Javed; Patel, Rajiv M; Harms, Kelly L; Lowe, Lori; Fullen, Douglas R; Harms, Paul W
description
Primary cutaneous neuroendocrine carcinoma, or Merkel cell carcinoma (MCC), cannot be distinguished morphologically from small-cell neuroendocrine carcinomas (SmCC) from other sites. Immunohistochemistry is required to confirm cutaneous origin, and is also used for detection of sentinel lymph node (SLN) metastases of MCC. Cytokeratin 20 (CK20) expression is commonly used for these purposes, but is negative in some MCC cases, and has unclear specificity. We evaluated immunohistochemistry for neurofilament and CK20 in MCC compared with SmCC from other sites.
